Nondeterministic X-Machine - Free Essay Example

Sample details Pages: 32 Words: 9529 Downloads: 4 Date added: 2017/06/26 Category Science Essay Type Descriptive essay Did you like this example? CHAPTER 5 Formal Modeling 5.1 Overview To achieve the maximum benefits from formal techniques, integration of approaches is required. In this chapter we present the integration of X-machine models and Z notation. The X-machine models sued to give the relationship between Z and X-machine are: (a) nondeterministic X-machine, (b) deterministic X-machine, (c) nondeterministic stream X-machine, (d) deterministic stream X-machine, (e) communicating stream X-machine, and (f) communicating stream X-machine system. The informal definitions of all these machines are taken from [1], [2], [3]. 5.2 Design of Nondeterministic X-Machine A Nondeterministic X-Machine is 10-tuple NXM = (X, Y, Z, , , Q, , F, I, T) where: Don’t waste time! Our writers will create an original "Nondeterministic X-Machine" essay for you Create order 1. X is a fundamental dataset on that the machine operates. 2. Y is a finite set of input alphabets. 3. Z is a finite set of output alphabets. 4. and are input and output partial functions, used to convert the input into the output sets from the fundamental sets, i. e., : Y X and : X Z. 5. Q is a finite nonempty set of states. 6. is type of M, a set of relations on X, i. e., : P (X X). The notation (XX) denotes a set of all possible partial functions from X to X. 7. F is a next state partial function, a transition function, i. e., F: Q x P Q, which takes a state a partial function and produces a new set of states. 8. I is a set of initial states, a subset of Q, and T is a set of terminal states, a subset of Q. NXM state: Q alphaIn: SigmaIn alphaOut: SigmaOut memory: Memory alpha: (SigmaIn Memory) beta: (SigmaOut Memory) function: Memory Memory trans: Q Memory Memory Q I: Q T: Q state I state T state q, q1: Q; m, m1: Memory; i: SigmaIn; o: SigmaOut q state q1 state m memory m1 memory i alphaIn o alphaOut m m1 function i m alpha o m1 beta s, s1: Q s state s1 state q m m1 s trans q1 m m1 s1 trans q m m1 = q1 m m1 s = s1 Invariants: a) The set of states states is a nonempty set. b) The set of initial states I is a subset of states. c) The set of final states T is a subset of states. d) For each input alphabet i and states q and q1, o an output alphabet, (i, m) belongs to elpha, (o, m1) belongs to beta (m, m1) belongs to set of partial functions trans ((q, (m, m1)), s) where transaction function acting on q and partial function gives a set of states. And the trans ((q1,( m, m1)), s1) gives a set of states. In the formal specification of NXM, Memory, SigmaIn, SigmaOut and Q are defined as abstract data types over which we cannot define any operation. To specify the NXM, we introduced a variable states to define the set of states of the NXM. Each element q in set states is of type Q therefore states is a type of power set of Q. To describe the sets of input and output alphabets, variables alphaIn and alphaOut of type of power set of SigmaIn and SigmaOut are defined respectively. Similarly, for memory the variable memory is of type of power set of Memory is introduced. Moreover, alpha and beta are the power set of partial functions of type (SigmaIn Memory) and (SigmaOut Memory) respectively, which converts an input alphabet s into an output alphabet g, by altering the memory. The variable function of type power set of (Memory Memory) is introduced to describe the set of all possible partial functions from Memory to Memory. The transition function trans of type (Q function) PQ is intr oduced to describe the transitions of the machine for each input (q, function), where q is a state and function is a partial function from memory to memory there must be a unique output q1 of type power set of Q. The set of initial states I is of type power set of Q and the set of final states T is of type PQ. 5.3 Design of Deterministic X-Machine A Deterministic X-Machine is 10-tuple DXM = (X, Y, Z, , , Q, , F, I, T) where: 1. X is a fundamental dataset on that the machine operates. 2. Y is a finite set of input alphabets. 3. Z is a finite set of output alphabets. 4. and are the input and output partial functions, used to convert the input into the output sets from the fundamental sets, i. e., : Y X and : X Z. 5. Q is a finite nonempty set of states. 6. is type of M, a set of relations on X, i. e., : P (X X). The notation (XX) denotes the set of all possible partial functions from X to X. 7. F is next state partial function, a transition function, i. e., F: Q x Q. It takes a state a partial function and deterministically produces a new state or the same state. 8. q0 is an initial state and T is a set of terminal states, a subset of Q. The above definition describes the deterministic X-machine because for each state q and for every partial function, there is a state q, i. e., F (q, ) = q. DXM states: Q alphaIn: SigmaIn alphaOut: SigmaOut memory: Memory alpha: SigmaIn Memory beta: SigmaOut Memory function: Memory Memory trans: Q Memory Memory Q q0: Q T: Q states q0 states T states q, q1: Q; m: Memory; i: SigmaIn; o: SigmaOut q states q1 states m memory i m alpha o m beta m m function trans q m m = q1 Invariants: a) The set states is a nonempty set. b) The q0 is an initial state. c) The set of final states T is a subset of states. d) For each input alphabet i and states q and q1, o is an output alphabet, (m, m1) is a relation on X to X, where (i, m) belongs to elpha, (o, m1) belongs to beta and (m m1) belongs to . The trans ((q, function), q1) describes the transaction function acting on q and the partial function giving the state q1. In the schema DXM the abstract data types, X, Y, Z and Q are denoted by Memory, SigmaIn, SigmaOut and Q respectively. In this schema we introduced variable states to define the set of states of the DXM. Each element q in set states is of type Q therefore states is a type of power set of Q. To describe the sets of input and output alphabets, variables alphaIn and alphaOut of type of power set of SigmaIn and SigmaOut are defined respectively. Similarly, for memory the variable memory of type of power set of Memory is introduced. Moreover, alpha and beta are the power set of partial functions of type (SigmaIn Memory) and (SigmaOut Memory) respectively, which converts an input alphabet s into an output alphabet g by altering the memory. The variable function of type power set of (Memory Memory) is introduced to describe the set of all possible partial functions from Memory to Memory. The transition function trans of type (Q function) PQ is introduced to describe the transitions of t he machine for each input (q, function), where q is a state and function is a partial function from memory to memory there must be a unique output q1 of type Q. The initial state q0 is of type Q and the set of final states T of type power set of Q. 5.4 Behavior of X-Machine To check the behavior of the machine, we get a sequence of input alphabets and checks that there exists a successful path for that particular sequence of inputs. This behavior checker accepts a deterministic X-machine a sequence of input alphabets and returns a sequence of output alphabets. Let DXM = (X, Y, Z, , , Q, , F, I, T) is a deterministic X-machine and a sequence of input alphabets seq Yi = y1, y2, , yn, where i = 1, 2,, n we say that there exist a sequence of partial function i = 1, 2, , n, where i = 1, 2,, n. Then we can say that DXM accepts the inputs when there exist a sequence of states si = s1, s2 sn, where i = 1, 2. . . n. In schema BDXM the variable stringIn? belongs to strings. The variable stringOut! belongs to messages. The length of input alphabets and output alphabets are equal. For all i belonging to the elements of cardinality of stringIn?, when the value of i is equal to 1 then there exists q, q1 states and m, m1 are memory states, q is the initial state, m1 b elongs to memory, for i-th element of stringIn? and m belongs to alpha there is a message of type SigmaOut which is the i-th element of stringOut!, and the transition function trans acting on state and and partial function (m, m1) gives a new state q1. It repeatedly reads the input from stringIn? and writes the messages on stringOut! by altering the memory until the final state is not reached or the there is no element in stringIn?. If the last state of the sequence of visited states is a final state then the whole string is accepted otherwise rejected. BDXM DDXM stringIn?: seq SigmaIn stringOut!: seq SigmaOut strings: seq SigmaIn messages: seq SigmaOut stringIn? strings stringOut! messages # stringIn? = # stringOut! i: i 1 .. # stringIn? i = 1 q, q1: Q; m, m1: Memory q = q0 q1 states m memory m1 memory stringIn? i m alpha stringOut! i m1 beta q m m1 dom trans q1 ran trans 1 i # stringIn? q, q1: Q; m, m1: Memory q states q1 states m memory m1 memory stringIn? i m alpha stringOut! i m1 beta q m m1 dom trans q1 ran trans i = # stringIn? q, q1: Q; m, m1 : Memory q = q0 q1 T m memory m1 memory stringIn? i m alpha stringOut! i m1 beta q m m1 q1 trans 5.5 Design of Nondeterministic Stream X-Machine A particular class of X-machine is Stream X-Machine which is defined as 8-tuple NSXM = (, , Q, M, , F, q0, m0), where: 1. is a finite set of input alphabets. 2. is a finite set of output alphabets. 3. Q is a finite nonempty set of states. 4. M is possibly finite set of memory on which the machine operates. 5. is a finite set of partial functions that map an input and a memory state to an output and a new memory state, i. e., : x M x M. 6. F is next state partial function that gives a state and a function from the type , P Q denotes the set of next states. F is often described as a transition state diagram, i. e., F: Q x PQ. For each state q and for every partial function , there is a power set of states P Q such that F (q1, ) = P Q. 7. The q0 is an initial state. 8. The m0 is an initial memory. NSXM states: Q alphaIn: SigmaIn alphaOut: SigmaOut memory: Memory function: SigmaIn Memory SigmaOut Memory trans: Q SigmaIn Memory SigmaOut Memory Q q0: Q m0: Memory states q0 states m0 memory q, q1: Q; m, m1: Memory; i: SigmaIn; o: SigmaOut q states q1 states m memory m1 memory i alphaIn o alphaOut i m dom function o m1 ran function s, s1: Q s states s1 states q function s trans q1 function s1 trans q function = q1 function s = s1 Invariants: a) The set states is a nonempty set. b) The state q0 is an initial memory. c) The memory element m0 is the initial memory. d) For each partial function ((i, m), (o, m1)) where i belongs to input alphabet, o belong to output alphabet, m and m1 of type memory, there exists a transition function trans ((q, function), s) acts on q and a partial function and return a set of states. In the formal specification of nondeterministic stream X-machine the description of the variables states, alphaIn, alphaOut, memory and q0 is same as previously defined in section 5.2. The variable function of type (SigmaIn Memory SigmaOut Memory) is introduced to describe the set of all possible partial functions from (SigmaIn Memory) to (SigmaOut Memory), which receives an input alphabet of type SigmaIn and returns an output alphabet of type SigmaOut by altering the memory. The transition function trans of type (Q function) PQ) is introduced to describe the transitions of the machine for each input (q, function), where q is a state and function is a partial function from (SigmaIn Memory) to (SigmaOut Memory), there must be a unique output q1 of type Q. The initial state q0 is of type Q and m0 is an initial memory of type Memory. 5.6 Design of Stream X-machine A particular class of X-machine is Stream X-Machine which is defined as 9-tuple SXM = (, , Q, M, , F, start, finals, m0) where: 1. is a finite set of input alphabets. 2. is a finite set of output alphabets. 3. Q is a finite nonempty set of states. 4. M is a possibly finite set of memory on which the machine operates. 5. a finite set of partial functions that map an input and a memory state to an output and a new memory state, i. e., : x M x M. 6. F is next state partial function that takes a state and a function from the type and gives next state. F is often described as a transition state diagram, i. e., F: Q x Q. For each state q1 and for every partial function , there is a new state q such that F (q1, ) = q. 7. The start is initial state and m0 is an initial memory. The symbols Q, Memory, SigmaIn and SigmaOut are the fundamental data types respectively. All the 9 tuples of stream X-machine are defined as: states of type Q, alphaIn of type SigmaIn is a set of input alphabets alphaOut of type SigmaOut is a set of possible messages that a machine can send, memory of type Memory which is possibly finite set of memory elements which can be a stack, queue, register, RAM or any type of memory. Set of partial functions is defined as function of type (SigmaIn Memory SigmaOut Memory), each element of function takes an input and memory element and returns a new memory state and message. The trans is the set of transitions of SXM of type (Q function) PQ which takes a function and state, returns a new state and message. The start is the initial state of type Q, and m0 is the initial memory of type Memory. The formal specification of stream X-machine in Z is given below. SXM states: Q alphaIn: SigmaIn alphaOut: SigmaOut memory: Memory function: SigmaIn Memory SigmaOut Memory trans: Q SigmaIn Memory SigmaOut Memory Q q0: Q m0: Memory states q0 states m0 memory q, q1: Q; d, d1: Memory; i: SigmaIn; o: SigmaOut q states q1 states d memory d1 memory i alphaIn o alphaOut i d dom function o d ran function q function dom trans q1 ran trans Invariants: a) The set of states is a nonempty set. b) The q0 is in set states. c) The memory element m0 is in set memory. d) For each partial function ((i, m), (o, m1)) where i belongs to input alphabet, o belongs to output alphabet and m, m1 of type memory there exists a transition function trans ((q, ((i, m), (o, m))), q1) where trans acts on q and partial function ((i, m), (o, m1)) returns a new state q1. 5.7 Design of Path of Stream X-machine A path is a connected sequence of arcs through the machine starting from one state and ending at another, possibly the same one. A successful path is one in which first state is the start state and last state belongs to final states. The behavior of X-machine is defined as the union of all the successful paths. To specify the PATH we declare XSXM which indicates that this is an operation in which the state does not change the values of states, alphaIn, alphaOut, memory, function, transition, q0 and m0 variables respectively. The variable arc of type of power set of (Q Q) is defined to denote the edge from q to q of type Q, and path is introduced to define the sequence of states from q0 to q where q is a final state. PATH XSXM arc: Q Q path: seq Q q, q1: Q q states q1 states sf: seq function; i: i # sf i 1 .. # path i + 1 # path path i states i dom path q function q1 trans q q1 arc path i path i + 1 arc sf i function Invariants: a) If q, q1 belong to states, belongs to and (q1, (q, )) belongs to trans, we say that function is the arc from q to q1, represented function: q q1. If q, q1 belong to Q such that there exist q1,, qn-1 in Q and 1,, n belonging to with 1: q q1, 2: q1 q2,, n:qn-1 q1 we say that we have a path p = 1 n from q to q1 and write p : q q1. 5.8 Design of Stream X-machine Computation The computation of stream X-machine is defined as stream X-machine and paths are accessed as read only which are defined in section 5.5 and 5.6. The input and output streams are defined as streamIn and streamOut of type sequence of SigmaIn and sequence of SigmaOut respectively. The variable epsiI is a nil input alphabet of type SigmaIn and epsiO nil output alphabet of type SigmaOut. SXM_Computation XSXM XPATH streamIn: seq SigmaIn streamOut: seq SigmaOut epsiI: SigmaIn epsiO: SigmaOut epsiI ran streamIn streamIn epsiO ran streamOut ran streamIn alphaIn ran streamOut alphaOut q: Q; m: Memory q states m memory epsiI m epsiO m function q function q trans q: Q; m, m1: Memory; g: SigmaOut; i: 1 i # streamIn i # path i + 1 # path q states m memory m1 memory g alphaOut i = 1 q = q0 q1: Q q1 states q0 q1 arc path i = q0 path i + 1 = q1 streamIn i m g m function q0 function q1 trans streamOut = streamOut g 1 i # streamIn q1: Q q1 states q q1 arc path i = q path i + 1 = q1 streamIn i m g m function q function q1 trans streamOut = streamOut g i = # streamIn q T q1: Q q1 states q q1 arc path i = q path i + 1 = q1 streamIn i m g m function q0 function q trans streamOut = streamOut g Invariants: a) The symbols streamIn and streamOut are the sequences of input and out respectively. b) The symbols epsiI and epsiO are the nil input and output alphabets respectively. c) Each element of input sequence belongs to the set of input alphabets of SXM and each element of output sequence must be from the set of output alphabets of SXM. d) The transition function for each state have the initial value as ((q, epsiI, m), (epsiO, m, q)) which shows it takes no input and gives no output. e) For each state q and q1 which belongs to arc there exists a path from q to q1 which give rise to a new function. f) Each element s of input sequence streamIn acting on memory m will give a new memory m1 and a new output element g which is concatenated with streamOut sequence (streamOut ^ g) at each iteration. In computation of stream X-machine the inputs and outputs are the streams of input and output alphabets. At each state a function is applied, the selection of next state depends upon the first input symbol, memory status and current state. The function computes the new memory state by updating the memory and produces output message which is concatenated at the tail of output stream. The first input alphabet is removed from the head of the input stream. This process continues in this way, while traversing the path and generating the output stream until the input stream is empty and a final state is reached. 5.9 X-Machine Model of an Ant Here we take the biological inspired intelligent agent as case study. The stream X-machine model of ant agent is given in Fig 5.1. The goal of the agent is to find food and carry it to their nest. This goal can be achieved by searching for food at random or follow the pheromone trails. When food is found it should leave pheromone trail moving back to its nest, when nest is found again it drops the food [16]. 1. Input alphabet is defined as ({space, nest} U FOOD) x COORD x COORD). 2. The set of outputs is defined as set of messages {moving_freely, moving_to_nest, dropping_food }. 3. The set of states Q in which agent can be are {At Nest, Moving Freely, At Food, Going Back to Nest, Looking for Food}. 4. Memory M of the agent is (FOOD U {none}) x (COORD x COORD) x sequence (COORD x COORD). 5. Initial memory m0 is defined as (none, (0, 0), nil). 6. Start state q0 is At Nest, (0, 0) is assumed the position of the nest. 7. The type is a set of functions of the form function_name (input_tuple, memory_tuple) (output, memory_tuple). [FOOD] Q ::At_Nest Moving_Freely At_Food Back_to_Nest Looking_for_Food SigmaOut ::moving_freely moving_to_nest moving_to_food lifting_food more_food dropping_food found_nest_again got_lost ignoring_food staying_at_nest FOOD is a basic type, Q is a set of states of an Ant and SigmaOut is a set of messages that an ant can send. Instruction: FOOD Instruction LOC: a, b: 0 a 0 b a b LOC SigmaIn: Instruction LOC SigmaIn LOC is a set of two dimensional locations, and SigmaIn is of type input alphabet which contains instruction and location. The Instruction is the set of all the possible instructions to the agent, which is either the name of a food item, belongs to FOOD or Space. The Space indicates that currently agent have no information about any food item or it have to stay at nest or ignore the food. The second element of each order pair is the location where the agent should have to move. CARRY: FOOD CARRY Memory: CARRY LOC seq LOC Memory Memory is the memory of agent where CARRY shows what the agent is carrying, LOC is the current location of the agent and seq LOC is the list of food items locations. Function: SigmaIn Memory SigmaOut Memory Function is the axiomatic definition of partial function which it gets an input alphabet and a memory element and returns a message as output alphabet and a new memory state by altering the memory. The Function is defined as an abstract data type to define all the possible operations that an Ant can perform. ANT DSXM none: FOOD nest: FOOD space: FOOD lift_food: Function move: Function move_to_food: Function move_to_nest: Function find_food: Function drop_food: Function find_nest: Function gotlost: Function ignore_food: Function stay_at_nest: Function m0 = none 0 0 q0 = At_Nest function = lift_food move move_to_nest move_to_food move_to_nest find_fooddrop_food find_nest gotlost ignore_food stay_at_nest i: Instruction; a, b, x, y: ; c: CARRY; list: seq LOC; o: SigmaOut; in: SigmaIn; m, m1: Memory; fpx, fpy: ; f: FOOD o alphaOut m memory m1 memory in = space x y o = moving_freely m = none a b m1 = none x y in m o m1 = move in = space x y o = moving_to_food m = none a b list m1 = none x y list fpx fpy in m o m1 = move_to_food in = space x y o = moving_to_nest m = f a b list m1 = f x y list in m o m1 = move_to_nest in = f x y o = lifting_food m = none a b list m1 = f x y list m1 = f x y list x y in m o m1 = lift_food in = f fpx fpy o = more_food m = f x y list m1 = f x y list x y in m o m1 = find_food in = nest 0 0 o = dropping_food m = f x y list m1 = none 0 0 list in m o m1 = drop_food in = nest 0 0 o = found_nest_again m = none x y list m1 = none 0 0 list in m o m1 = find_nest in = nest fpx fpy o = got_lost m = none x y fpx fpy m1 = m0 in m o m1 = gotlost in = f 0 0 o = ignoring_food m = none 0 0 list m1 = m in m o m1 = ignore_food in = nest 0 0 o = staying_at_nest m = none 0 0 list m1 = none 0 0 list in m o m1 = stay_at_nest q: Q; f: Function f function q states q = At_Nest f = ignore_food q f q trans q = At_Nest f = stay_at_nest q f q trans q = At_Nest f = move At_Nest f Moving_Freely trans q = At_Nest f = move_to_food q f Looking_for_Food trans q = Moving_Freely f = move q f q trans q = Moving_Freely f = find_nest q f At_Nest trans q = Moving_Freely f = lift_food q f At_Food trans q = Looking_for_Food f = gotlost q f Moving_Freely trans q = Looking_for_Food f = lift_food q f At_Food trans q = Looking_for_Food f = find_nest q f At_Nest trans q = Looking_for_Food f = move_to_food q f q trans q = At_Food f = move_to_nest q f Back_to_Nest trans q = Back_to_Nest f = find_food q f q trans q = Back_to_Nest f = move_to_nest q f q trans q = Back_to_Nest f = drop_food q f At_Nest trans Invariants: a) lift_food, move, move_to_food, move_to_nest, find_food, drop_food, find_nest, gotlost, ignore_food, stay_at_nest are the functions of an Ant. All the functions have the same type as the function of SXM. Each function is an element of function. b) The memory element m0 is an initial memory state which shows that agent carrying nothing currently, its current location is At_Nest and the list of food elements is empty. c) The state q0 is an initial state which is At_Nest. d) The function is the new state of function of SXM which is the set of all the possible actions that an ant can perform. e) All the possible operations an agent can perform are defined as functions in which it takes an input of type Instruction, LOC and a MEMOEY element of type FOOD U {none}, current location of the agent and list of food items, and generates a new memory status by altering the current memory and returns a message. f) For each input in of type (Instruction LOC) in the set of alphaIn of SXM a memory element m in memory of SXM, m1 in new state of memory memory and output alphabet o in set of SigmaOut, there exist a partial function of type Function in function where (in, m) in set domain of function and (o, m1) is in set range of function. g) For each partial function f in function where in is input alphabet, o is output alphabet and m, m1 of type memory, and q, q1 of type Q in set states of an Ant, there exists a transition function trans ((q, f), q1) where trans acts on q and partial function f and returns a new state q1. The SXM imposed all the general constraints that an Ant should posses, but the specific data types and functions of an Ant are different from a general SXM. Therefore there is a need to define all the functions and other required data types which are used in an Ant specification. By using the we can reuse the SXM schema in ANT schema. Further there is no need to redefine all the SXM data types. We only define the following abstract data types SigmaIn, SigmaOut, Memory, Q and functions. The variable none of type FOOD describes that currently the agent is carrying nothing, nest and space of type FOOD indicate where the agent have to move, i. e., either stay at nest of moving freely. All the operations that an agent can perform are define as lift_food, move, move_to_nest, move_to_food, find_food, drop_food, find_nest, goltlost, ingnore_food and stay_ at_nest are of type Function. The formal specification of agent Ant is given below. 5.10 Design of Communicating Stream X-Machine A communicating stream machine is a stream X-machine with the following four different types of functions of type, i: (s, m) = (m, g), where s i, g i, m, m Mi. a). Functions that read the input from the standard input stream and write their output to the standard output stream, i. e., i: (s, m) = (m, g). b). Functions that read the input from a communication input stream and write their output to the standard output stream, i. e., i: (sj, m) = (m, g). c). Functions that read the input from the standard input stream and write their output to a communication output stream, i. e., i: (s, m) = (m, gk). d). Functions that read the input from a communication input stream and write their output to a communication output stream, i. e., i: (sj, m) = (m, gk). These functions are named as SISO, ISSO, SIOS and ISOS which are defined below. SISO: SI is the standard input stream and SO is the standard output stream. The function SISO read the input from the standard input stream and write their output to the standard output stream, i. e., SISO: ((s, m) = (m, g). ISSO: IS is the input stream of another machine j and SO is the standard output stream. The function ISSO read the input from a communication input stream and write their output to the standard output stream, i. e., ISSO: (sj, m) = (m, g). SIOS: SI is the standard input stream and OS is the communicating output stream. The function SIOS read the input from standard input stream and write their output to communicating output stream k, i. e., SIOS: (s, m) = (m, gk). ISOS: IS is the communicating input stream and OS is the communicating output stream. The function ISOS read the input from communicating input stream j and write their output to communicating output stream k, i. e., ISOS: (sj, m) = (m, gk). The formal specification of communicating stream X-machine is described in schema CSXM. CSXM DSXM SISO: SigmaIn Memory SigmaOut Memory SIOS: SigmaIn Memory SigmaOut Memory ISSO: SigmaIn Memory SigmaOut Memory ISOS: SigmaIn Memory SigmaOut Memory ist: seq SigmaIn ost: seq SigmaOut is: seq seq SigmaIn os: seq seq SigmaOut ist ran is ost ran os function = SISO SIOS ISSO ISOS i: ; isq: seq SigmaIn i 1 i isq is j: 1 j j # isq isq j alphaIn i: ; osq: seq SigmaOut i 1 i osq os j: 1 j j # osq osq j alphaOut i, j, k: 1 i i # ist 1 j j # ost 1 k k j m, m1: Memory; sq: seq SigmaIn; gq: seq SigmaOut m memory m1 memory sq ran is sq = ist gq ran os gq = ost # sq I # gq i sq i m dom SISO gq i m1 ran SISO m, m1: Memory; sq: seq SigmaIn; gq: seq SigmaOut m memory m1 memory sq ran is sq = ist gq ran os # sq I # gq k sq i m dom SIOS gq k m1 ran SIOS m, m1: Memory; sq: seq SigmaIn; gq: seq SigmaOut m memory m1 memory sq ran is gq ran os gq = ost # sq j # gq i sq j m dom ISSO gq i m1 ran ISSO m, m1: Memory; sq: seq SigmaIn; gq: seq SigmaOut m memory m1 memory sq ran is gq ran os # sq j # gq k sq j m dom ISOS gq k m1 ran ISOS Invariants: a) The ist belongs to the range of is. b) The ost belongs to the range of os. c) The function is the new state of set of functions which is the union of the above mentioned four types of functions. d) Each element of each communicating input stream is in the set of input alphabets alphaIn. e) Each element of each communicating output stream belongs to the set of output alphabets alphaOut. f) For each input and output there exist m belongs to memory and m1 belongs to new state of memory memory. For each i, j and k are integers from 1 to the length of input sequence, there exists m and m memory elements and if gq and sq belong to standard output and input streams then (sq i, m) belongs to domain of SISO and (gq i, m1) belongs to range of SISO. If gq belongs to communicating output stream k then (sq i, m) belongs to domain of SIOS and (gq k, m1) belongs to range of SIOS. Whenever sq belongs to communicating input stream j then (sq j, m) belongs to domain of ISSO and (gq i, m1) belongs to range of ISSO, further when sq and gq are communicating input and output streams j and k respectively then (sq j, m) belongs to domain of ISOS and (gq k , m1) belongs to range of it. The formal specification of communicating stream X-machine is same as stream X-machine except these four functions. So, we reuse the specification of SXM and define these four functions and relationship between communicating functions and SXM which becomes a CSXM. Data and communication are modeled separately, data is modeled in SXM and communication is modeled in CSXM which provide the benefit of reusability of SXM models. The variables SISO, SIOS, ISSO and ISOS of (SigmaIn Memory) (SigmaOut Memory) are defined to describe the four different combinations of input and output streams. The ist and ost are the standard input and out streams of type sequence of SigmaIn and sequence of SigmaOut respectively. The variable is is introduced to define the sequence of input streams of type sequence of SigmaIn and os is defined to describe the sequence of output streams of type sequence of SigmaOut. 5.11 Design of Communicating Stream X-machine System A communicating X-machine system consists of a number of X-machines that can exchange messages with each other. A CSXMS is defined as Z= ((Ci)i=1,, n, CR) where: 1. Ci is a i-th communicating X-machine component. 2. CR is a relation which defines the communication between the communicating X-machine components, i. e., CR C C and C = {C1, , Cn}. A tuple (Ci, Ck) CR denotes that the X-machine component Ci can output a message to a corresponding input stream of the X-machine component Ck for any i, k {1, . . . , n}, i k. Z C: CSXM CR: CSXM CSXM c, c1: CSXM c C c1 C c c1 CR c c1 m, m1: c . memory; s: SigmaIn; g: SigmaOut s ran c . ist g ran c . ost s m dom c . SISO g m1 ran c . SISO m, m1: c . memory; s: SigmaIn; g: SigmaOut s ran c . ist g ran c1 . ost s m dom c . SIOS g m1 ran c . SIOS m, m1: c . memory; s: SigmaIn; g: SigmaOut s ran c1 . ist g ran c . ost s m dom c . ISSO g m1 ran c . ISSO m, m1: c . memory; s: SigmaIn; g: SigmaOut s ran c1 . ist g ran c1 . ost s m dom c . SIOS g m1 ran c . SIOS Invariants: For each c and c1 of type CSXM where (c, c1) is in relation CR, there exists m, m1 of type memory of machine c. Input and output alphabets s and g are of type SigmaIn and SigmaOut respectively. If s belongs to the range of standard input stream ist of machine c and g belongs to the range of standard output streams ost of machine c then the partial function (s, m), (g, m1) belongs to function SISO. Further if g belongs to the output stream of machine c1 then the partial function (s, m), (g, m1) belongs to SIOS. Similarly, if s belongs to the input stream of machine c1 then the partial function (s, m),(g, m1) belongs to ISSO, otherwise the partial function (s, m), (g, m1) belongs to ISOS. The formal specification of CSXMS is described in schema CSXM where we introduced a variable C of type power set of CSXM to define a set of communicating stream X-machines. CR is a relation of type power set of (CSXM CSXM), where c and c1 are communicating stream X-machines which can communicate with each other. 5.12 Traffic Control System We take the case study of traffic control system to use the complete proposed formal modeling technique on an agent-based system. The case study is selected to demonstrate the applicability of the integrated formal modeling approach. This is accomplished by using the traffic control system which is derived from an original text written in [4]. The traffic control system is composed of the following components, queue of cars, traffic signal lights and controller as illustrated in Fig 5.1. The scenario of the problem is as follows: a) To make sure the safe depart of the cars that arrive at the traffic junction. b) The cars are waiting in the queue to depart. If the signal is red then cars wait until the signal becomes green. c) When a new car arrives it is added at the tail of the queue and when a car leaves it leaves from the front of the queue. 5.12.1 Components of the System The traffic control system is composed of the following components called agents. a) Traffic queue agent b) Traffic signal agent and c) Controller agent. 5.12.2 Traffic Queue Agent The traffic queue agent is characterized by following elements. a) A queue of traffic holds the sequence of cars arrived at the junction. b) Traffic arrived at queue are added at the tail of the queue. c) Traffic leaves the queue when signal is green. d) Make sure the safe depart of traffic at the junction. The X-machine model of traffic queue is illustrated in Fig. 5.2, where the input set of X-machine is: = {arrive, leave}. The input alphabet is a composite type that contains an input and a car. The output of the system consists of a set of messages that may displayed on the screen = {FirstArrived, NextArrived, CarLeft, LastCarLeft, NoCarInQueue}. The set of states is: Q= {empty, queuing}. The machines memory M is a sequence of cars. The set of function is {first_arrives, arrives, leaves, last_leaves, reject}. TrafficQueue DSXM first_arrives: FUNCTION arrives: FUNCTION leaves: FUNCTION last_leaves: FUNCTION reject: FUNCTION q0 = empty m0 = function = first_arrives arrives leaves last_leaves reject i: Input; c: CAR; g: SigmaOut; s: SigmaIn; m, m1: Memory i c SigmaIn s SigmaIn m memory m1 memory s = arrive c m = m0 m1 = c s m FirstArrived m1 = first_arrives s = arrive c m m0 m1 = m c s m NextArrived m1 = arrives s = arrive head m m m0 m1 = tail m s m CarLeft m1 = leaves s = arrive head m m m0 m1 = m0 s m LastCarLeft m1 = last_leaves s = arrive c m = m0 m1 = m0 s m NoCarInQueue m1 = reject q: Q; f: FUNCTION q states f function q = empty f = first_arrives q f queuing trans q = queuing f = arrives q f queuing trans q = queuing f = leaves q f queuing trans q = queuing f = last_leaves q f empty trans q = empty f = reject q f empty trans Invariants: a) The state Empty is the start state. b) Initial memory is an empty sequence of cars. c) The function is the new state of functions of queue. d) All the functions of X-machine take an input alphabet and memory element and return a message by altering the memory value. e) All the transitions of the machine take a state and a function and return a new state by altering the memory, read the input and return a message. [CAR] Q ::empty queuing Input ::arrive leave SigmaOut ::FirstArrived NextArrived CarLeft LastCarLeft NoCarInQueue Memory: seq CAR SigmaIn: Input CAR Function: SigmaIn Memory SigmaOut Memory CAR is a fundamental data type and Input is of type instruction. Memory is a set of sequences of cars. SigmaIn of type power set of (Input CAR), which contains an instruction and a car. Function is an abstract type of function which is defined to describe the functions of the queue. To define all the tuples of queue we reuse the general specification of stream X-machine SXM as defined in section 5.5. The formal specification of X-machine of a queue is presented above using Z notation. The function of the machine takes an input alphabet and a memory element, and returns output alphabet and new memory state. In the formal specification of traffic queue agent, we write SXM to denote the schema SXM that defines all the tuples of the general stream X-machine. The variables first_arrives, arrives, leaves, last_leaves and reject are the functions of type Function which traffic queue agent can perform. 5.12.3 Communicating Traffic Queue Agent The previously defined X-machine of a queue of cars can communicate with signal light in such a way: when the traffic light becomes green, the queue is notified to leave a car, and cars can depart one by one until there is least one car in the queue. More cars can arrive to the queue, waiting for a signal to depart. Whenever there is a green signal from the traffic light but there is no car in the queue the machine ignores the signal. Functionality of the communicating X-machine is defined as: The first_arrives and arrives functions read from standard input stream and write on standard output streams. The functions leaves, last_leaves and reject read from the communication stream of signal light instead of standard input stream and write the output to the standard output stream of TrafficcQueue. In this way every car leaves the queue whenever thers is a message from the signal light to leave that makes sure the safe depart of the car from junction. It may also write to a communicating input stream of another X-machine. The normal output of the functions is not affected. The definition of function in TrafficQueue changes from that in the definition of CommTrafficQueue. To specify the communicating traffic queue agent we reused the specification of TrafficQueue and CSXM schema. There is only need to define the communicating functions of the machine through which it can communicate with other agents of the system. CommTrafficQueue XTrafficQueue DCSXM SISO = first_arrives arrives SIOS = SIOS ISSO = leaves last_leaves reject ISOS = ISOS is = is os = os Invariants: a) In communicating X-machine of traffic queue, the definition of functions first_arrives and arrives remain same. The set of function SISO which read from and write on standard input and output streams respectively. It becomes SISO which contains two functions first_arrives and arrives. b) The definition of functions leaves, last_leaves and reject are changed as it reads from communication input stream and writes on standard output stream. The set of functions ISSO contains three function leaves, last_leaves and reject. c) The set of functions SIOS and ISOS remains same as SIOS and ISOS. d) The standard input and output streams is and os remains unchanged as is and os. 5.12.4 Traffic Light Agent A traffic light agent is characterized by the following elements: a) Two light signals red and green, b) Holds the total number of ticks elapsed since the last change of signal, c) Holds the number of ticks that a signal should be displayed, d) Holds the number of ticks before start the working and e) Switch between the signals. All the tuples of X-machine of traffic light agent are defined as: a) Set of input alphabets is a set of time unit called ticks. b) A set of output alphets = {Red, Green, Statrup}. c) The memory of the agent is defined as: (timeelapsed, delay, DurGreen, DurRed), where timeelpased shows the number of ticks elapsed since last signal changed, delay defines the times required to start, and DurGreen and DurRed are used to define the period of a signal to be displayed respectively. d) The set of functions of the agent are defined as: function = {delay, change_green, keep_green, change_red, keep_red}. The functions are activated by reading the input of type TICK. e) The transition functions of the agent are illustrated in Fig 5.4. f) The set of states is defined as = {red, green}. g) The state red is an initial state and m0 is the initial memory of agent. Q ::red green SigmaOut ::RedColour GreenColour StartUp Memory: i, j, k, l: 0 i 0 j 1 k 1 l i j k l Memory SigmaIn: TICK TICK is the abstract data type which is introduced to define the set of input alphabet SigmaIn of type power set of TICK. A TICK indicates a clock tick. Q is the set states of the agent. Memory is a set of possible memory elements of the agent which is defined as a power set of type (Z Z Z Z), where Z is a non negative integer value. To formally specify the traffic light agent we reuse the specification of SXM which defines all the tuples of the agent. Here we only define the particular functions of the agent which are delay, change_green, change_red, keep_green and keep_red of type Function. TrafficLight DSXM delay: Function change_green: Function change_red: Function keep_green: Function keep_red: Function q0 = red m0 = 0 20 60 40 function = delay change_green change_red keep_green keep_red g: SigmaOut; s: SigmaIn; m, m1: Memory; w, x, y, z: s alphaIn g alphaOut m memory m1 memory 0 w 0 x 1 y 1 z w x y z Memory m = m0 x 0 x = x 1 m1 = w x y z s m StartUp m1 = delay w z w = w + 1 m1 = w x y z s m RedColour m1 = keep_red w y w = w + 1 m1 = w x y z s m GreenColour m1 = keep_green w = z m1 = 0 0 y z s m GreenColour m1 = change_green w = y w = w + 1 m1 = 0 0 y z s m RedColour m1 = change_red q: Q; f: Function q states f function q = red f = keep_red q f red trans q = red f = change_green q f green trans q = red f = delay q f red trans q = green f = keep_green q f green trans q = green f = change_red q f red trans q = green f = delay q f green trans Invariants: a) The state red is the start state. b) Memory is initialized as (0, 20, 60, 40). c) The function is the new state of functions of traffic light. d) All the functions of x-machine are defined as: it takes an input alphabet and memory element and returns a message by altering the memory value. The transition of the machine takes a state and a function and returns a new state by altering the memory, read an input and write an output. 5.12.5 Communicating Traffic Light Agent A communicating traffic light agent communicates with traffic queue agent and controller agent. It sends a message to traffic queue agent which will be an input to the agent. It receives messages from controller agent to switch the signal as illustrated in Fig 5.5. The change_green function receives a message from controller and changes the signal from read to green and send a message to traffic queue agent to allow the cars to leave the queue one by one. It is assumed that one car leaves the queue in one tick. The change_red function receives a message from the controller agent and writes on its standard output stream. In formal specification of communicating traffic light agent the specification of stand alone light agent is reused to define the communicating agent. Further predefined specification of abstract communicating stream X-machine is also reused which defines the communicating functions of the agent. The formal specification of communicating traffic light agent is given below. CommTrafficLight XTrafficLight DCSXM SISO = delay keep_red SIOS = keep_green ISSO = change_red ISOS = change_green is = is os = os Invariants: a) In communicating X-machine of traffic light, the definition of functions delay and keep_red remain same. The set of functions SISO which reads and writes on standard input and output streams respectively becomes SISO that contains two functions delay and keep_red. b) The definition of functions keep_green is changed as it reads from standard input stream and writes on communication output stream. The set of functions SIOS contains a function keep_green. c) The set of functions ISSO and ISOS contains function change_red and change_green respectively. d) The standard input and output streams is and os remain unchanged as is and os. 5.12.6 Controller Agent The controller agent is used to control a number of traffic light agents. In our case study we assume that there are four traffic light agents with their corresponding traffic queue agent and hence there must be a need of controller that controls the light agents. The controller agent controls the multiple light agents by scheduling on the basis of round robin scheduling technique as illustrated in Fig 5.6. The controller is also responsible for the synchronization and allocation of time share to traffic lights. Q ::schedule_light1 schedule_light2 schedule_light3 schedule_light4 Memory: SigmaOut: SigmaIn ::clock_pulse switch_device Q is the set of states which contains schedule_light1, schedule_light2, schedule_light3 and schedule_light4. Memory and SigmaOut are of type power set of natural numbers. SigmaIn is a set of input alphabets which contains clock_pulse and switch_device. Controller DSXM operate: FUNCTION switch: FUNCTION q0 = schedule_light1 m0 = 0 function = operate switch g: SigmaOut; s: SigmaIn; m, m1: Memory s alphaIn g alphaOut m memory m1 memory s = clock_pulse g = m + 1 m1 = m + 1 s m g m1 = operate s = switch_device g = m m1 = m s m g m1 = switch q: Q; f: FUNCTION q states f function q = schedule_light1 q operate schedule_light1 trans q = schedule_light1 q switch schedule_light2 trans q = schedule_light2 q operate schedule_light2 trans q = schedule_light2 q switch schedule_light3 trans q = schedule_light3 q operate schedule_light3 trans q = schedule_light3 q switch schedule_light4 trans q = schedule_light4 q operate schedule_light4 trans q = schedule_light4 q switch schedule_light1 trans Invariants: a) The state schedule_light1 is the start state. b) Memory is initialized as (0). c) The variable function is the new state of functions of controller agent. d) All the functions of x-machine are defined as: it takes an input alphabet and memory element and returns a message by altering the memory value. All the transitions of the machine take a state and a function and return a new state by altering the memory, read an input and write an output. The formal definition of controller agent is defined as: The set of input alphabets = {clock_pulse, switch_light}. The output alphets are defined as a set of natural numbers. The memory of the agent is defined as a set of natural numbers. The set of functions of the agent are defined as: function = {operate, switch}. The transition functions of the agent are illustrated in Fig 5.4. The set of states is defined as {S1, S2, S3, S4}, where S1, S2, S3 and S4 are the instances of the traffic light agent. S1is the initial state and (0) is the initial memory of agent. 5.12.7 Communicating Controller Agent The communicating controller agent communicates with traffic lights to change the signal. It sends message tick to light agent and receives the message switch_device from the traffic light agent which provides a synchronization mechanism. In formal specification of communicating controller agent, the predefined stand alone controller agents specification is reused to define the communicating controller agent. Further predefined specification of abstract communicating stream X-machine is also reused which defines the communicating functions of the controller agent. The formal specification of communicating traffic light agent is given below. ComController XController DCSXM SISO = operate SIOS = SIOS ISSO = ISSO ISOS = switch is = is os = os Invariants: a) In communicating X-machine of controller agent the function operate remains same as defined in CSXM. The set of functions SISO which read from and write on standard input and output streams respectively becomes SISO that contain a function operate. b) The definition of function switch is changed as it reads from standard input stream and writes on communication output stream. The function ISOS contain a function switch. c) The set of functions SIOS and ISSO remain unchanged. d) The standard input and output streams is and os remain unchanged as is and os. 5.11.8 Agent based Traffic Control System The agent-based traffic control system (ABTCS) consists at a controller agent and four traffic light agents with corresponding traffic queue agents. The controller agent switches the signals of the traffic light agents. The traffic light agent communicates with controller agent and also with its corresponding traffic queue agent. The traffic queue agent only communicates with a single traffic light agent. To formally specify the ABSTCS we redefine the communicating stream X-machine system because there are three types of agents which communicate with each other. Therefore the existing definition cannot be used to define the ABTCS. In schema TrafficControlSystem the variables C1 of type power set of CommTrafficQueue is introduced to define the set of communicating traffic queue agents, C2 of type power set of CommTrafficLight to describe the set of communicating traffic light agents and C3 of type ComController to introduce the communicating controller agent. The variable CR is defined as a relation of type (CommTrafficQueue CommTrafficLight ComController) which defines a relationship between traffic queue agent, light agent and controller agent and provides a mechanism in which they can exchange messages. TrafficControlSystem C1: CommTrafficQueue C2: CommTrafficLight C3: ComController CR: CommTrafficQueue CommTrafficLight ComController cq: CommTrafficQueue; cl: CommTrafficLight; cc: ComController cq C1 cl C2 cc C3 cq cl cc CR In the above specification the invariant is defined as for all cq of type CommTrafficQueue, cl of type CommTrafficLight and cc of type ComController such that cq belongs to C1, cl belongs to C2 and cc belongs to C3 which holds that (cq,cl, cc) belongs to relation CR which indicates that these three agents can communicate with each other. To specify the ABTCS we introduced the variables queue1, queue2, queue3 and queue4 to define the four queue agent of type communicating queue agents. Similarly, light1, light2, light3 and light4 are introduced to describe the four traffic light agents which can communicate with other agents of the system. The controller agent is defined as controller. The variables nilq, nils and nilc are introduced to define the null value of sets C1, C2 and C3. This specification shows that we are not defining all the agents from scratch we just specify a single agent of one type and then we can create instance of these agent with different initial memory values an d start state according to the requirements. AgentBasedTrafficControlSystem DTrafficControlSystem queue1, queue2, queue3, queue4, nilq: CommTrafficQueue light1, light2, light3, light4, nils: CommTrafficLight controller, nilc: ComController queue1 . q0 = empty queue2 . q0 = empty queue3 . q0 = empty queue4 . q0 = empty light1 . q0 = green light2 . q0 = red light3 . q0 = red light4 . q0 = red light1 . m0 = (0, 0, 20, 60) light2 . m0 = (0, 20, 20, 60) light3 . m0 = (0, 20, 20, 60) light4 . m0 = (0, 20, 20, 60) queue1 . m0 = queue1 . m0 = queue1 . m0 = queue1 . m0 = C1 = {queue1, queue2, queue3, queue4, nilq} C2 = {light1, light2, light3, light4, nils} C3 = {controller, nilc} Invariants: a) In this specification we define the four instance of traffic queue agent. The initial state q0 and initial memory m0 of all the traffic queue agent is initialized by empty and empty sequence respectively. b) The initial state q0 of traffic light agent light1 is initialized by green which means that when the system starts the signal of traffic light1 must be green and the signal of the remaining light agent light2, light3 and light 4 must be read. c) The initial memory m0 of traffic light agent 1 is set to (0,0,20,60) which shows that at the startup it immediately starts working without waiting a single tick, it must remains green and red till 20 and 60 ticks respectively. d) The traffic light agents light2, light3 and light4 are defined with initial memory (0, 20, 20, 60). e) The set of communicating traffic queue agents is changed from C1 to C1 and consists of queue1, queue2, queue3 and queue4 agents. f) The set of communicating traffic light agents is changed from C2 to C2 and consists of queue1, queue2, queue3 and queue4 agents g) C3 the set of controller agents contains a single agent controller.

Kurt Cobain Informative Speech Essay - 1990 Words

â€Å"I remember watching Kurt come through and thinking, â€Å"God, this music is nuclear,† This is really splitting the atom. They raised the temperature for everybody. Manufactured pop never looked so cold as when that heat was around. Nirvana made everything else look silly.† -Bono of U2 is quoted in Lorraine Alis, †Cries From The Heart,† a Newsweek article published on October 28, 2002. Today I would like to tell you the story of my favorite artist Kurt Cobain the lead singer of Nirvana. Ill be covering his early life, his struggle with the fame of his band, and his death. The story of Kurt Cobain is a story of great talent, hardship and tragedy. But it is a story that needs to be heard and one i think we can all relate to in some way.†¦show more content†¦One time Kurt was riding in a limo to play at a gig in Seattle, his friend Amy was in the car with him and she has reported, that he explained to her, that usually they would take a van to gi gs and that the limo was not a decision he had made. She says that he made a point of stressing this to her the whole way, that was the last time she saw him. Kurt felt a lot of resentment for his past and the way in which he grew up, not toward his parents, but more aimed at the world and the way that society was constructed. In Television and radio interviews he would often talk about how screwed up the world was. That he didnt see how anybody could possibly consider bringing a child into the world the way it was. Kurt spent most of his life in depression, with the exception of a few years in the early 90s, this is reflected in the music he wrote, but Kurt had reason to feel this way, the life he had was never close to what he wanted. The only thing that kept Kurt going through all the pressure and embarrassment he felt towards fame, was the music he was producing and playing the world over. However his passion was slowly diminishing. All the touring and pressure got to him in the end, Kurt became ill. His mother had suffered with stomach problems in her early 20s and Kurt had began to suffer the same illness. The doctors could not determine what was the cause, they put it down to stress. Kurt tried to

A Response Paper On Christopher Steiner’s Free Essays

Christopher Steiner’s article entitled ‘Authenticity, Repetition, and the Aesthetics of Seriality’ talks about the ‘mechanical reproduction of art’ at the height of technological improvement and technical production nowadays. He discusses Walter Benjamin’s essay entitled ‘The Work of Art in the Age of Mechanical Reproduction’ in the issue that: first, mechanical reproduction is not just a new form of technical production but engenders â€Å"an entirely new philosophy of production in which the work of art is emancipated† (Steiner 88); and second, that the mechanical reproduction and consumption of art makes the object more accessible to wider population (88). His argument, therefore, is that â€Å"to justify the authenticity of tourist art one must begin from an entirely different starting point† (89), since tourist art should be viewed as a culturally valid, authentic art. We will write a custom essay sample on A Response Paper On Christopher Steiner’s or any similar topic only for you Order Now    He argues that mass-produced art carries an authenticity, which it shares with other mass-produced objects in the industry. What I argue, however, is that mechanical reproduction of art does not carry anymore the authenticity and validity of what a true art should be—that it should be an expression of views, beliefs, and culture of an individual or a number of individuals.   Objects that undergo mass production are merely ‘reproductions’ of the original item.   The true ‘art’ is in its originality. This means that, although the reproduced object is an exact image of the original object, it is merely a mimic and is not an expression of the self.   When it comes to being culturally valid, however, I agree that objects that undergo mass production are, indeed, culturally valid, since it reveals a certain aspect of culture that, though reproduced again and again, still holds the originality and the individuality that the culture and the people reflect. Art is like what a human being is: it is a reflection of culture and society, yet it cannot be an exact replication of the other—for there is none like it.   Mass-produced objects of art contain authenticity and validity in terms of culture art, but not as an individual art. Works Cited Steiner, Christopher.   â€Å"Authenticity, Repetition, and the Aesthetics of Seriality: The Work of Tourist Art in the Age of Mechanical Reproduction.†Ã‚   [name of book].   Ed. [name of editor].   Place: publisher, year.   87-103. How to cite A Response Paper On Christopher Steiner’s, Papers

Annual Reports of firms group - free sample - MyAssignmenthelp.com

Questions: Discuss about theFirms Annual Reports. Answers: The Prada is a recognised Italian luxury fashion house that is renowned for its specialization in leather bags, travel accessories, shows, men and womens clothing, perfumes and other types of fashion accessories. The success achieved by the company is on the basis of its creative business model developed through combination of its efficient production process with artisanal skills (Prada Group, 2016). It can be stated from the Chief Executive review of the year 2016 that the company has made strong plans for supporting its brand development. The company is emphasising on enhancing the geographic expansion of its retail business for ensuring its long-term growth. However, the company has faced significant challenges for achieving its business goals and objectives due to uncertainty in the global market. The company has done some of the changes in its operational activities for strengthening its production processes and meeting its new business objectives. The company has also develope d and implemented the cost reduction strategies by simplifying its business operations for enhancing its profitability (Prada: Annual Report, 2016). The operational expenditure of the company has reduced in the year 2016 as compared to the previous year by Euro 206.7 million despite of the key measures adopted by it to enhance its profitability position. The income statement of the company has reflected a decline in the EBIT of 71.7 million in the year 2016 as compared to the year of 2015. The balance sheet of the company also reflects a net increase in the financial figures of its non-current assets of property, plant and equipment. The net income of the company in the year 2016 is reported to be Euro 278.3 million as compared to the Euro 330.9 million in the year 2015. The non-current assets has reported an increase from Euro 2,586.8 million to Euro 2599.6 million due to capital expenditure incurred by the company for supporting its expansion plans . There is also an increase in the current assets of the company due to reduction in the tax payables. The working capital of the company has reported a reduction due to finishing of the product inventories and reviewing of the business strategies for replenishing the retail stores. Besides, the key strategies developed by the company for supporting its growth and development it are not able to achieve improved growth. The net cash flows from the operating activities have also been declined in the year 2016 as compared to the previous year. The reduction in the profitability despite of the initiatives taken for improving the operational processes is a matter of main concern for the company. The company is not able to increase its sales in the new geographical locations and therefore requires the development of new strategies for attracting customers (Prada: Annual Report, 2016). The company for ensuring the success of its long-term plan of business expansion in diverse geographical area is planning to take several initiatives. The major initiatives taken by the company in this regard is developing new and innovative products for the customers with high quality and best prices. The company has designed new products in several categories such as leather goods and handbag designing. In addition to this, it is also placing large emphasis on renovating its retail stores for providing better shopping experience to the customers. The company has developed a global vision of strengthening its brand image in all parts of the world in the coming period of time (Prada Group, 2016). The company is incorporating the use of advanced digital technologies and tools and developing highly qualified team for empowering its brands in diverse geographical areas. These efforts of the company will ensure it to achieve sustainable growth through providing high quality products based on creative ideas. The digital technologies will help in distributing the products to the customers in a short interval of time. Also, the use of new technology devices will help the company to interact with large customer base in a short span of time and thus providing knowledge about their products and services. The company for achieving its business objectives of providing innovative styling products to the customers is facing the major challenge of reducing its operational expenditure. The significant increase in its operating expenses is the major reason for its reduction in profitability position in the year 2016 (Prada: Annual Report, 2016). However, it can be said from analyzing the annual report of the company that the presentation of its financial results is different from other major retail companies such as Woolworths, Tesco and others. There is no segregation in the annual report of the company such as directors or remuneration or the financial report as can be clearly seen in the annual reports of other companies. It is very interesting for me to review the financial position of such a company that is based on central idea of creativity and innovation. It has helped me to understand the importance of creativity for gaining customer satisfaction and its significance for gaining a unique position in the marketplace (Prada: Annual Report, 2016). Blog Post about My Company My company is Prada Group, a well-renowned Italian luxurious retail company. The company has achieved a distinctive position due to its unique styled products mainly in categories of handbags, fashion accessories, footwear, perfumes, men and women clothing. I am extremely happy for gaining an opportunity to analyse the business functions and activities of this company. This is because the company has achieved a distinctive image in the marketplace due to its creative and innovative products. I myself have a large interest in developing of products based on creative ideas that is the main theme of this company. The company emphasizes mainly on achieving customer attraction through providing them unique styled products in fashion accessories. The analysis of the financial statements of the company for the year 2016 has revealed that despite of its strong efforts for gaining customer attention it is not able to increase its revenue generation in the new foreign markets. However, as per the financial reports for the year 2017 the company profitability position ha significantly improved showing that its new business strategies are proving it to be successful for improving its performance in the long-term. References Prada. 2016. Annual Report. [Online]. Available at: https://www.pradagroup.com/system/pdf_ens/280/original/e-Annual%20Report%202016.pdf [Accessed on: 7 September 2017]. Prada Group. 2016. [Online]. Available at: https://www.prada.com/en.html?cc=AP [Accessed on: 7 September 2017].

Procedure for applying Muskingum Method Essay Example

Procedure for applying Muskingum Method Paper For Muskingum method which is a hydrologic method, the discharge measurements alone are sufficient for routing. This is because it is assumed that the parameters of the Muskingum model capture the combined flood-propagating characteristics of a river reach. When the water resources schemes to be built are in their initial planning stages, the river gauging system may remain either underdeveloped or insufficient to give precise and rigorous measurements of flow depths and discharges. The Muskingum method is useful for predicting the preliminary outflow hydrographs required at the initial stages of planning spillway capacities. In addition, these outflow hydrographs can also aid the design of stream gauges for future use. Hence, the Muskingum model has a high significance for modern civil engineers (Das 2004 p. 130) The Muskingum equation is frequently used for routing of floods in river channels. The Muskingum method for routing flood waves in rivers and channels has been widely used in applied hydrology, since its first use in connection with a flood control project in the Muskingum County of Ohio about fifty years ago. Since its development around 1934 by McCarthy, the Muskingum method has also been a subject of many investigations (Strupczewski, Napiorkowski Dooge 2002 p. 235) The figure below shows the translational and storage processes in stream channel routing. We will write a custom essay sample on Procedure for applying Muskingum Method specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Procedure for applying Muskingum Method specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Procedure for applying Muskingum Method specifically for you FOR ONLY $16.38 $13.9/page Hire Writer (Gill 1979 22) The Muskingum method as explained above is a widely used hydrologic method for routing flood waves in rivers and channels. The standard procedure for applying the Muskingum method involves two basic steps: calibration and prediction. In the calibration step, inflow-outflow hydrograph data is taken from historical records to determine the parameter values for the Muskingum model of a river. This is used to solve the parameter-estimation problem. The prediction step is the solution of a routing problem in which the outflow hydrograph for a given inflow hydrograph is determined by using the routing equations. Figure below shows an example of routing using Muskingum method (Elizabeth 1994) Disadvantages of Hydrologic Routing The primary disadvantage is that the dynamic flow effect is not taken into account. In addition it is assumed that stage and storage is a single–valued function of discharge implying flow is changing slowly with time. This may not be true always, and is a case of oversimplifying things. Muskingum Equations Muskingum equation is a spatially lumped form of continuity equation and linear-storage and discharge relationship for a specified river reach. The first equation is common to all conceptual models. It is a physical continuity equation i. e. law of conservation of mass, which is later integrated over the entire river reach   (1) Muskingum method differs from other conceptual models with the second equations, which relates storage in the river reach, inflow and outflow. The equation (2) given above can be obtained by assuming that the total storage in the river reach is a weighted sum of the storages, corresponding to steady-state flow rates in terminating cross-sections, and that a linear relation exists between the prismatic storage and the flow rate. As we have seen in the sections above the two types of storages prism and wedge, and the functions which they depend on. Revisiting the same we get Prism storage = ; Wedge storage = The above equations can be rewritten as Prism storage = ; Wedge storage = The total storage volume at any time instant, t, can be calculating the above two storages.

The Rise of Youtube and the Causes of Internet Music piracy The WritePass Journal

The Rise of Youtube and the Causes of Internet Music piracy Bibliography The Rise of Youtube and the Causes of Internet Music piracy IntroductionBibliographyRelated Introduction Sharing of illegal musical contents is becoming very popular nowadays. Sharing tools and many websites such as Kazza and Pirates bay are considered as a major source for downloading musical tracks and albums from the Internet around the globe. There are many reasons which have caused these illegal acts to emerge. One of the possible causes is the high cost of some albums and concert tickets. Many musical concerts might ask for very high entry fee. Example of this is the ticket price of a local concert for an artist named Stevie Wonders at Yas Island which is set to a price of Dhs250! Some CD and DVD packages might be little overpriced as well; however, several websites such as Amazon offer used CD albums while other websites such as iTunes offer cheap Mp3 tracks and albums for as low as 1$ Â  ( 4Dhs). Another possible cause is the diversity of tools and methods used by the pirates to publish the stolen and illegal material. Tools such Ares, Shareeza, and Kazza could be downloaded easily into your computer and use the P2P technology to acquire all the latest albums. The P2P (peer to peer) technology allows thousands of persons to share the same album and even allow the illegal users to comment on and rate these contents. There are several search engines created to find the illegal peers (distributors) such as torrentz.com website which connects thousands of violating sites. There are also several website where you can search for recorded musical events too. Several sites exist like YouTube where people can upload and watch HD quality full concerts for free with subtitles which make it more convenient for them than paying for the ticket money. Some people might also use forums and blogs to distribute such albums. Twitter (which is a blogging site) is an excellent source for the leak ed mp3 tracks downloads. A third cause of this major issue is the lack of moral and legal knowledge about this issue. For instance, many of the teens nowadays think that it’s not bad to download songs from the Internet. A recent study made by Barna group discovered that only eight percent of the sample of 1448 teenagers thinks it’s morally wrong to download music illegally from the internet (Ventura, 2004). As a result, several laws are enforced to protect Artist’s rights such as the UAE Copyright Law .These laws range from huge fines to impressments of copy-right violators, but these laws are mostly implemented heavily on companies rather than particular persons and this might seem quite disappointing. As a conclusion, it’s hard to ignore the several causes that made some Internet users distribute copied music contents through the Internet. It will be better to educate these persons on the possible effects of their actions. Bibliography Moore, C. W. (2003, August 8). Is Music Piracy Stealing? Retrieved March 12, 2011, from Applelinks: applelinks.com/mooresviews/pirate.shtml Stevie Wonders. (n.d.). Retrieved 03 12, 2011, from Yas Island: yasisland.ae/en/events-calendar/flash-events/yas-island-show-weekends/concerts/stevie-wonder-live-on-yas-island/ Ventura. (2004, April 26). Fewer Than 1 in 10 Teenagers Believe that Music Piracy is Morally Wrong. Retrieved 03 12, 2011, from The Barna Group: barna.org/barna-update/article/5-barna-update/139-fewer-than-1-in-10-teenagers-believe-that-music-piracy-is-morally-wrong

Pro's Google Medical Records Essay Example | Topics and Well Written Essays - 750 words

Pro's Google Medical Records - Essay Example Medical information has long been stored by doctors, hospitals, clinics and housewives. Doctors, hospitals and clinics have always used the medical charting system, keeping notes in thick files. Medical information was misread, misplaced, faded, and suffered a variety of accidents. Information was shared over telephones and FAX machines, or more often not shared at all. Bits and pieces would perhaps find their ways to a summer camp director, a human resource department, an insurance representative or some other storage destination, where it would become buried and inaccessible to the person whose body was the subject. Each member of the medical team responsible for the health of a given patient, stored only a limited set of medical information and there was little to no coordination of care (Gassee, 2010). To further complicate the patient’s fractured health picture, given the notoriously illegible handwriting of overly-busy doctors, what information there was in storage was o ften inaccurately interpreted. Without access, a patient could not take responsibility to correct inaccurate information. Inaccuracies became compounded. Google’s medical records storage system digitizes all the information and stores it in a central location, online. All members of the medical team, and patient-designated others, have easy access to accurate information, along with the patient (Seidman, 2011). Accuracy is enhanced by patient access to clearly organized records which, like credit card information or educational transcript information, can be corrected when errors are pointed out. Security, a critical issue, is well-assured with Google. Under the old charting system, the patient could not keep track of who had what personal medical information. There was no way to take information access away from those who had access. Google increases medical information security by linking access invitation, always generated by the patient, to specific e-dresses, keeping acc ess power and access-revocation power under patient control (Gassee, 2010). The patient can always see who has viewed personal medical information. Shared records are read-only (Kincaid, 2009). Probably the most important policy implemented by Google, with regard to use of their EMR, is that they will not share any information with anybody, without specific user permission to do so (Google Health, 2011). This policy clearly puts the patient, and not Google or â€Å"Big Brother†, in charge. Without this policy being in place and assured, those forecasting science fiction nightmares about lack of privacy and loss of self-determination, would have a point. Google is a technological giant. Such a massive undertaking as this EMR represents, requires human expertise and impressive computer capability. Google has more success in scalability than most other organizations. They have more than 2.5 million servers indexing and storing data daily, so they are experienced with this sort o f thing (Gassee, 2010). Furthermore, Google has joined forces with a consortium, to develop a software platform that automatically uploads medical information from home healthcare devices (Kirkpatrick 2009). They have associated with partner hospitals, pharmacies, etc., to link information, for the convenience of doctors and patients alike (Google Health, 2011). Google’

Suggested Essay Example | Topics and Well Written Essays - 250 words

Suggested - Essay Example An educator needs to figure out which category best fits needs of every student. The educator should not try to fit all adult learners into one group as each student has different goals in his mind. Understanding life circumstance of an adult learner may also help educators to anticipate their needs. A student typically returns to school for a better professional image and increased career opportunities. Educators need to be aware of trends while assessing how to address need of each student. Some of these needs are: students who work in occupations generally labeled nonprofessional, professionals who want to change career fields, displaced professionals, workers who are concerned about being displaced and professionals who need a degree to make the next vertical step within their organizations. As listed above, there are many reasons why an adult student feels the need to continue with hiseducation. Educators need to educate themselves so they can better help each student to choose the best career path for what they desire to accomplish. However, understanding the circumstances surrounding return of an adult to school is imperative when providing quality suggestions as how to accomplish each goals of each student. Some students will not have the desire or time for a typical four year college program, so will be looking for shorter programs that offer quicker access to better paying jobs. Short term programs that provide rewarding work and better pay hold a strong appeal to most time-strapped adults. Educators and students need to be aware that students who have been in the workforce for a significant amount of time will have earned substantial school credits from work-time experience. This will help encourage adults to continue with their education. This article also state s â€Å"students with a high number of undergraduate credits can often complete a General Studies

Applied managment & theory - xerox case study Assignment

Applied managment & theory - xerox case study - Assignment Example In order to analyse the change of management in Xerox, it is necessary to adopt many management theories to analyse friction by friction. PEST analysis, comprising of Political, Economical, sociocultural and technological factors, according to which the marketing environment is made up of three aspects, internal environment, micro environment, macro environment etc. The internal environment consists of staff that is also called internal customers, office technology, wages and finance etc. Micro environment is external customers, agents and distributors, suppliers, out competitors etc. Macro environment consists of Political and legal forces, economic forces, sociocultural forces and technological forces etc. PEST is concerned only with the Macro Environment, which is concerned with the production of the company. "The first is efficiency in the production of a given set of outputs. That is, with a given capital stock a given technology and a given set of resource prices, firms should be producing goods and services with a minimum expenditure of the economy's resources," (Cyert, 1988, p.36). Xerox had to overcome many problems while going through Change Management. It could not compete with the Japanese competitors because of high manufacturing cost. Internal culture and leadership suffered due to mindsets bordering towards complacent inertia. But later, leadership went through an immense transformation that led to the present enviable state of the company. It improved the quality of its products and the organisation turned the corner. In 1990s, Xerox introduced digital photocopiers, high-end laser printers with attached scanners and these products made Xerox march ahead of its competitors in this mercurial field. "Xerox worked to turn its product into a service, providing a complete "document service" to companies including supply, maintenance, configuration and user support." http://en.wikipedia.org/wiki/Xerox Xerox created excellent name for itself in the employment front as well. Company received 100% rating on the first Corporate Equality Index from the Human Rights Campaign in 2002. "They have maintained this rating in 2003, 2004, 2005. Xerox has been recognized by a number of other organizations for its diversity leadership as well." Ibid. As far as the political factors are concerned, the political scenario has a very large influence on business. It depends on the stability of the political environment, how could the tax regulation going to affect the company, what could be the Government's stand in marketing ethics, government's economic and industrial policy etc. It also depends on its religious or secular policies and if they are religion oriented enough to disturb other cultures or if there are any regional or international agreements and compulsions. Xerox did not face many problems due to political problems in home country, but it must have faced problems in other countries like Asian Specific countries, and to some extent, in India. "But, according to a recent article (Cordtz, 1974, "Xerox is moving into an awkward agethe company resembles a muscular adolescent who has grown so fast that he finds it difficult to coordinate his newly acquired strength" (page 117)" (Burke, 1977, p.22). In economic factors deal with market trends, economic predictions, theories of long and short term both, international market trend, any upcoming national and

Discussions Of Population Growth And Resources Environmental Sciences Essay

Discussions Of Population Growth And Resources Environmental Sciences Essay Natural resources are a subject of constant debate in the contemporary political and economic scene. Forms of appropriation, exploitation and trade of such resources affect in crucial way international relationships, and they are even a cause of violent conflicts. But its importance goes further. Their allocation has been always a crucial element due to its effects in the economy; its possession determines the economical organization and political development of a region. Today, there is an increasing awareness of the need for production systems to incorporate the objective of sustainable development. In order to manage this, natural resources should be renewal, in the sense that they are the determining condition for sustaining a long-term economic dynamic. Looking at this approach, natural resources are regarded as a link between societies and the environment. But what is the really relationship between population and natural resources? Is it sustainable? The study of interactions between population growth and the environment has a long history. According to Malthus 1, a growing population exerts pressure on agricultural land, forcing the cultivation of land of poorer and poorer quality. This environmental degradation affects natural resources and reduces the marginal product of labor and, through its effect on income, lessens the rate of population growth. The result is an equilibrium population that enjoys low levels of both income and environmental quality. But, the modern economic models replace agricultural land with nonrenewable resources. In this model, natural resources impose a limit to economic growth, with population pressures reducing economic development as scarce natural resources are exploited more intensively. However, a more recent theme in discussions of population growth and resources is the importance of environmental quality, measured by the stock of forests or by absence of air and water pollution. In this view the environment is seen not as a factor that limits productivity as populations expands, but as good whose quality is degraded by a growing population. In fact, population pressures, for example, are frequently cited as a cause of deforestation: population growth, by increasing the need for arable land, encourages the conversion of forest land to other uses. Moreover, it is related to the major cause of air, water and solid-waste pollution. In the past, the main cause of alarm was the depletion of natural resources. Many specialists repeatedly calculated how long the reserves of coal, oil, etc., will last. Now source of alarm is an entire complex of questions relating to the interaction between man and the environment. As in any other natural ecosystem, the increase in population means an increasing pressure on it. In the case of the human population, such pressure is even greater because it is not only a numerical increase, but also associated with the creation and diversification of new needs. This qualitative aspect is reflected in demands on resources, which are scarcer and scarcer. 2Nevertheless, the effects of population growth cannot be discussed independent of other factors that can cause resource and environmental pressures. While it makes sense to ask about relative importance of population in causing these pressures, it cannot be forgotten tastes, technology, institution policies and international relations. These and other determinants strongly condition the resource and pressure generated by population growth; they often change and affect the situation more than do demographic changes within specific time periods; and they often interact with each other and with demographic variables. But focusing on the sustainability of this relationship; there are at least three reason of why concerns about population growth have retreated over the last years. First,3 the demographic transition, which refers to the idea that at sufficiently high incomes, fertility tends to fall, owing to voluntary family size decisions. Indeed, fertility has fallen significantly in those parts of the world where most educated people live such as Unite States, Europe and East Asia. In spite this trend, population for the world as a whole is still growing rapidly. Second, population growth can be related to the technology optimism, which points out that increasing population is a positive force on living standards, largely because of induced innovation arising from population pressure. This model put an end on the Malthusian problem which 1said that there was a possibly tendency of human population to grow more rapidly that can be accommodated by arable land and other components of the source base. Third, it is related to political or ideological considerations. Population concerns are often in conflict with the strongly pro-natal positions of several major religions, particularly with the fundamentalist elements that have grown in influence over the past few decades. Cornering now about environmental degradation, especially air and water pollution, and concerning about depletion of natural resources like forests and oil reserves has become a significant issue. Both, environmental damage and resource depletion derive from the same fundamental question regarding the interaction of economic activity and the natural environment. Thus, important natural resources include environmental resources such as air and water, agricultural resources in the form of land and soil; renewable resources such as forests, fisheries and wildlife; and non-renewable resources such as oil and various metals and minerals. Global warming is a somewhat distinct topic, although it interacts closely with environmental, agricultural and renewable resources and is an important cause of resource degradation. Following studies like Limit to growth 4 put on the table whether the present growth trends continue unchanged, the limit to growth on this planet will be reached sometime within the next 100 years. The most probable result will be a sudden and uncontrollable decline in both population and industrial capacity. Looking at this premonition, the word sustainability becomes widely used in discussion of resource use. Unfortunately, the term was used in a variety of different ways, leading to significant semantic confusions. Therefore, extending this sustainable concept to an entire economy seems difficult. 5This concept cannot apply to non-renewable resources. Petroleum that is used up cannot be replaced by new petroleum. So, it makes more sense to apply the concept to energy sources that can replace the non-renewable ones. Building the right infrastructures might include facilities to produce hydroelectric power, solar energy, wind energy, and so on. The issue is whether this sustainable word has appeared too late, because human has already cause huge damages. Some of them have even affected our own specie. 5About 3 million people die annually due to contamination. In the past decade and in every environmental sector, conditions have not improved. For example, contaminated water, together with poor sanitation, kills over 12 million people a years, mostly in developing countries. Air pollution kills another 3 millions. And heavy metals and other contaminates also cause widespread health problems; Will we have enough food to feed everyone? In 64 of the 105 developing countries studied by FAO (United Nations Food and Agriculture), the population has been growing faster than food availability. The population pressures have degraded some 2.000 million hectares of arable land, an area the size of Canada and the United States together. About the fresh water: The availability of freshwater is finite, but demand is rising rapidly as the population grows and increasing use per capita. By 2025, when projected to the worlds population reaches 8.000 billion is expected that 48 countries, containing 3.000 million people will face water shortages. Focusing now in coastal and oceans; half of all coastal ecosystems are under pressure due to high population densities and urban development. In the worlds oceans is rising tide of pollution. The ocean fishery is being overexploited, and fish catches or harvests have declined. 1 Clausen, AW 1985, Population Growth and Economic and Social Development, Journal of Economic Education, 16, 3, pp. 165-176. 2 Ridker, Ronald G. Population and Economic Growth: Resource and Amenity Implications of Population Changes. American Economic Review 64, no. 2 (May 1974): 33 3 Peyrache-Gadeau, V 2007, Natural Resources, Innovative Milieux and the Environmentally Sustainable Development of Regions, European Planning Studies, 15, 7, pp. 945-959 . 4Smith, V. Kerry, and John V. Krutilla. Economic Growth, Resource Availability, and Environmental Quality. American Economic Review 74, no. 2 (May 1984): 226 4HOMER-DIXON, T 2011, GROWTH WONT LAST FOREVER, Foreign Policy, 184, p. 56 5 Don Hinrichsen and Bryant Robey; Population and the Environment: The Global Challenge Johns Hopkins University report, september 2000

An Introduction To Expert Systems Essay examples -- Technology Compute

An Insight into Expert Systems Abstract To improve speed of operations, programming practices for practical purposes are moving away from the data centric, procedural problem solving paradigm to a heuristic, declarative problem solving paradigm. Though theoretically there is no guarantee that a solution shall be found and even if it is found, that it be correct, practically it has been proven that expert systems employing , heuristics are indeed a faster and more effective manner of problem solving , with an added advantage of having an explanation for the answer arrived at. Having started out as a diagnostic tool, it has now found acceptance all over, be it Manufacturing Firms or IT Solution Providers and is definitely here to stay. Its dependence on Artificial Intelligence furthermore proves its capabilities to branch out to more areas of deployment. With the advent of commercial-off-the-shelf expert system development tools making the process of designing an expert system a simple task, now the real challenge lies with the experts to be able to put these their knowledge and expertise in their domain to effective use to create systems which can be put to use effectively. Expert Systems are a branch of Artificial Intelligence that makes an extensive use of specialized knowledge to solve problems at the level of a human expert. AI's scientific goal is to understand intelligence by building computer programs that exhibit intelligent behavior. The term intelligence covers many cognitive skills, including the ability to solve problems, learn, and understand language; AI addresses all of those. But most progress to date in AI has been made in the area of problem solving -- concepts and methods for building programs that reas... ...tive. The IFE may also use a variety of techniques, particularly when carrying out the dialogue with the user to produce the specification of the user's problem. Research has flattened out when compared to the days of its inception as a practice, as more efforts have been employed in tapping its commercial value. To maximize this, other systems such as database and fuzzy logic systems are being embedded into expert systems. Drawbacks Expert systems are said to have a narrow domain and limited focus. Also they do not have a learning ability which is something AI systems are expected to. They require rigorous maintenance procedures and incur huge developmental costs. Bibliography 1. Knowledge Based Systems in Japan (http://www.wtec.org/loyola/kb/) 2. Databases and Artificial Intelligence 3 by Alison Cawsey (http://www.macs.hw.ac.uk/~alison/ai3notes/)

Social Policy And Society Education Essay

Whose Needs are being met by Scots schooling? Discuss the assorted stakeholders ( kids, parents, society, the province ) , there possible demands and measure how good they are met. The province recognises the demand for kids to be educated. It is recognised as a right, a duty and a necessity. Society no longer relies as to a great extent on the male staff of life victor theoretical account and as a effect parents in the bulk of instances no longer have the option of supplying kid attention and instruction to their kids themselves. As we are come ining an age of hi tech fabrication and developing a high skilled economic system the authorities is besides looking for an educated population and can no longer work with a society of nonreader or ill educated citizens. An uneducated population would besides be less antiphonal to authorities runs and information or counsel and may be unable to carry through their function in society and the democratic procedure. Children themselves, it has been acknowledged, have a right to be educated ; â€Å" No individual shall be denied the right to instruction † ( European Convention on Human Rights ; agenda 1, article 2 ) .That does non nevertheless intend that the instruction provided is what kids want or what they need. Neither does it intend that chief watercourse instruction in Scotland is provided with everyone ‘s best involvements in head. All of the parties mentioned supra will hold unfavorable judgments or be disappointed by what province instruction in Scotland provides to some extent ; nevertheless I wish to do it clear that for the bulk of stakeholders the Scots instruction system provides acceptable results. Besides, in recent old ages important stairss have been taken in Scotland to better the instruction system for those interest holders presently losing out, chiefly kids themselves, and I wish to analyze this in more item. In 2009 there were 676,740 students in publically funded schools in Scotland ( Scots authorities ; pupil Numberss ) and educational outgo was ?4.87 billion in 2007-08 ( Scots authorities ; Expenditure on school instruction in Scotland ) . This amounts to a important proportion of Scotland ‘s population presently in the Scots public instruction system and a important proportion of national disbursement. Spending on instruction sums to a big proportion of public disbursement and must hence be a high precedence for the authorities, denoting that it is a high precedence for society as a whole. Equally good as being a right under the ECHR ( European Convention on Human Rights ) instruction is besides a right under the Universal declaration of human rights enshrined in UK jurisprudence in the Human rights act 1998 ; â€Å" Everyone has the right to instruction. Education shall be free, at least in the simple and cardinal phases. Elementary instruction shall be compulsory†¦ .. † ( Universal declaration of human rights ; article 26 ( 1 ) ) and in the UNCRC ( United nations Convention on the right of the kid ) , â€Å" To guarantee that all sections of society, in peculiar parents and kids, are informed, have entree to instruction and are supported in the usage of basic cognition†¦ † ( UNCRC ; article 24, 2 ( vitamin E ) ) . Few public services are as strongly protected by rights and Acts of the Apostless as those sing entree to instruction. Yet to what extent instruction should be provided and who its chief focal point should be on remains ill-defined. For many old ages statements raged about Scots instruction merely being good to the ‘average ‘ kid and that those who needed extra support demands or who did non work good within formal educational scenes were being left behind or ignored for the greater good. The Scots authorities has hence gone a long manner in recent old ages to try to turn to this. The school course of study in Scotland is non statutory but alternatively the authorities sets out a model which it so expects instructors to work within. The newest model published is the ‘Curriculum for excellence ‘ . This model is built around four Nestor notabilis capacities that the Scots authorities want to instil in every Scots immature individual by the terminal of their clip in instruction. It is besides really to a great extent based on current research that suggests the best manner to prosecute all students in the schoolroom is by utilizing inter disciplinary accomplishments and different acquisition and learning methods such as undertakings, e-learning, talks and peer on equal rating. The Scots authorities claim ; â€Å" The course of study aims to guarantee that all kids and immature people in Scotland develop the properties, cognition and accomplishments they will necessitate to boom in life, larning and work. This is encapsulated in the four capacities – to enable each kid or immature individual to be a successful scholar, a confident person, a responsible citizen and an effectual subscriber † . ( Learning and Teaching Scotland ; Curriculum 3-18 ) However what good are these results if so many immature people find themselves go forthing instruction with no or really few significance makings and no utile trade or work related accomplishments? The benchmark for mensurating pupil attainment in Scotland is the SCQF ( Scots recognition and making model ) mark. At the age of 14 to 15 about every kid in Scotland will sit a set of standard class tests. 5 plus base on ballss at SCQF degree 4 ( standard class general ) is considered the minimal criterion of attainment that could be merited with success and which could take to patterned advance through those makings. School conference tabular arraies are drawn up based on how good pupils did in this quartile and yet 24.4 % of Scots pupils fail to accomplish this benchmark about a one-fourth of all Scots immature people ( Scots authorities ; SQA attainment and school departer makings in Scotland: 2008/09 ) . On top of this 14.53 % of immature people go forthing Scots schools in 2009 were non in instruction employment or preparation and therefore had no positive finish ( Scots authorities ; Destinations of Leavers from Scots Schools: 2008/09 ) . This barely seems like a system which empowers every immature individual to develop accomplishments that will do it possible for them to ever happen a positive finish in society. It may besides demonstrates that there attack has so far failed to convey about touchable consequences which will profit all the stakeholders in the Scots instruction system. The authorities nevertheless may good indicate out that a major component of their reforms of Scots instruction will come in the signifier of alterations to the makings system. These alterations will non be implemented nevertheless until 2016 when the SQA ( Scots Qualifications Authority has drafted, approved and tested the new scrutinies, designed to concentrate on Nestor notabilis accomplishments and development of literacy and numeracy throughout all school topics. There has besides been a important displacement in the attitudes held towards helping kids with acquisition and Behavioural issues or disablements in Scots instruction and in bridging the spread between young person work, schools and less formal educational attacks. The Education ( Additional Support for Learning ) ( Scotland ) Act 2004 was introduced to supply statutory protection to all immature people in Scots instruction who feel they may necessitate more support. Article 1 ( specifying extra support demands ) provinces ; â€Å" A kid or immature individual has extra support demands for the intents of this Act where, for whatever ground, the kid or immature individual is, or is likely to be, unable without the proviso of extra support to profit from school instruction provided or to be provided for the kid or immature individual † This means that any kid in Scotland for whatever ground who feels like they may necessitate extra support are lawfully entitled to it. This jurisprudence has been to a great extent advertised and publicised nevertheless the resources to endorse up this statute law and supply the support are frequently highly over stretched and exhausted. The Bridging the Gap study between young person work and schools was another advanced thought that the Scots authorities hoped would better the instruction system for all interest holders but peculiarly those for whom chief watercourse instruction was non appropriate the study aimed to ; â€Å" Put the policy context and offer illustrations of pattern to promote youth work and school partnerships across Scotland to present more chances to prosecute and animate immature people. â€Å" ( Learning learning Scotland ; bridging the spread study, page5 ) This attack to instruction and presenting young person work and community acquisition in to the school scene shows a willingness to do instruction more accessible and relevant to all pupils and to prosecute everyone in the acquisition procedure. Whether or non this plan will hold any success remains to be seen. Scots instruction hence does present for the bulk of stakeholders most of the clip. It provides a child care option for parents between the kid ‘s age of 5 and 16. It keeps the bulk of the population literate and able to hold on basic numeracy and it gives a high figure of school kids a opportunity to derive accomplishments and addition cognition which will assist them travel in to farther instruction, employment or preparation. It is clear that there is still a proportion of society which the current Scots instruction system is non supplying for nevertheless the Scots authorities has gone a long manner in its efforts to undertake issues with the system and has succeeded in supplying a system which meets most of the demands of most of its stakeholders.