Lect 10: DEVS Modeling Process and Implementation in DEVSim++

Transcription

1 Lect 10: DEVS Modeling Process and Implementation in DEVSim++

2 OO Modeling vs DEVS Modeling Process 2 of 32 OO Modeling by Observation of real world Step 1:Identify objects and associated attributes Step 2: Identify operations of each objects Step 3: Establish visibility of each objects to other objects Step 4: Establish interface for each object Step 5: Implement each object DEVS Modeling by Identification of a real system Step 1: Identity atomic and coupled models Step 2: For each atomic model Identify input, output and state (X, Y, S) Identify four characteristic functions (ta, d int d ext l) Step 3: For each coupled model Identity input, output and components (X, Y, Mi) Identity three coupling relations (EIC, EOC, IC) Identify priority of components (sel) Step 4: Implement each atomic model Step 5: Implement each coupled model Step 6: Testing / Debugging

3 DEVS Development Methodology Step 1 3 of 32 Step 1: Identity atomic and coupled models Coupled Model Specifies the structure of the system Atomic Model Specifies the behavior of the system GEN+BUF+PROC BUF+PROC out in out in done GEN BUF PROC out S : G Root C : G+B+P S : B C : B+P S : P SELECT G B P G B B P G P GEN ta(buf) : ta(proc) :

4 DEVS Development Methodology Step 2 4 of 32 Step 2: For each atomic model Identify input, output and state (X, Y, S) Identify four characteristic functions (ta, d int d ext l) Atomic Model class CAtomic (C++ class interface of Atomic Model) X bool AddInPorts(int num,...); Y bool AddOutPorts(int num,...); S Member Variable d ext bool ExtTransFn(const CMessage &) d int bool IntTransFn() l bool OutputFn(CMessage &) ta TimeType TimeAdvanceFn()

5 Interrupt Event(1/2) 5 of 32? in A 5!out B!out 0 5? in!out ? in *? in!out A 5!out B Interrupt Event: Input event which does not change existing event schedules(using Continue)

6 Interrupt Event (2/2)? in 6 of 32 A B!a 5!a C 3!out 1 0 5? in!out!a? in * !a A 5!out B 1? in!out!a C

7 Review: Definition of Atomic Class QueueServer in API 7 of 32 class QueueServer : public CAtomic public: QueueServer(); ~ QueueServer(); virtual bool ExtTransFn(const Cmessage &); virtual bool IntTransFn(); virtual bool OutputFn(CMessage &message); virtual TimeType TimeAdvanceFn(); ; // Atomic Model: QueueServer // external transition function // internal transition fucntion // output function // time advance function bool QueueServer ::ExtTransFn(const CMessage &message)... bool QueueServer ::IntTransFn()... bool QueueServer ::OutputFn(CMessage &message)... TimeType QueueServer ::TimeAdvanceFn()...

8 DEVS Development Methodology Step 3 8 of 32 Step 3: For each coupled model Identity input, output and components (X, Y, Mi) Identity three coupling relations (EIC, EOC, IC) Identify priority of components (sel) Coupled Model class CCoupled(C++ class interface of Coupled Model) X bool AddInPorts(int num,...); Y bool AddOutPorts(int num,...); M bool AddComponent(int num,...); EIC,EOC,IC bool AddCoupling( CModel *src_model,const char *src_port, CModel *dst_model, const char *dst_port); SELECT bool SetPriority(int num,...);

9 DEVS Development Methodology Step 4 (1/2) 9 of 32 Step 4: Implement each atomic model class QueueServer : public CAtomic public: QueueServer(); ~ QueueServer(); virtual bool ExtTransFn(const Cmessage &); virtual bool IntTransFn(); virtual bool OutputFn(CMessage &message); virtual TimeType TimeAdvanceFn(); ; // Atomic Model: QueueServer // external transition function // internal transition fucntion // output function // time advance function bool QueueServer ::ExtTransFn(const CMessage &message)... bool QueueServer ::IntTransFn()... bool QueueServer ::OutputFn(CMessage &message)... TimeType QueueServer ::TimeAdvanceFn()...

10 Server.status DEVS Development Methodology Step 4 (2/2) 10 of 32 in B F QueueServer out in 0 Queue Server Queue.length Server.status out in out in out in X = in Y = out S = (length,status) length I, status B, F d ext ((n 0,-),in) = (n+1,-) d ext ((0,F),in) = (1,B) d int ((n 1,B)) = (n-1,b) d int ((n=1,b)) = (0,F) l((n 0,-)) = out ta((n 0,-)) = Service_time out queue.length (n) bool QueueServer::OutputFn(CMessage &message) bool class QueueServer::ExtTransFn(const if(!isstate(length, 0)) public CAtomic CMessage &message) message.setportvalue(out, NULL); public: if(message.getport() return true; == in ) QueueServer(); if(!isstate (length, 0)) ~QueueServer(); SetStateValue(length, GetIntStateValue(length)+1); virtual else if(isstate(length, bool ExtTransFn(const 0) && IsState(status, CMessage &); F)) TimeType QueueServer::TimeAdvanceFn() virtual SetStateValue(length, bool IntTransFn(); 1); virtual SetStateValue(Status, bool OutputFn(CMessage B); if(isstate(length, 0)) &); virtual return TimeType Service_Time; TimeAdvanceFn(); ; return true; else return Infinity; QueueServer::QueueServer() bool QueueServer::IntTransFn() AddInPorts(1, in ); if(!isstate(length, AddOutPorts(1, 1) out ); && IsState(status, B )) AddStateVariables SetStateValue(length, (2, length, GetIntStateValue(length)-1); status ); InitStateValue SetStateBale(status, ( length, B); new Integer(0)); InitStateValue ( status, new String( F )); else if(isstate(length, 1) && IsState(status, B)) SetStateValue(length, 0); QueueServer::~QueueServer() SetStateBale(status, F); return true;

11 DEVS Development Methodology Step 5 11 of 32 Step 5: Implement each coupled model SingleSeverQueue Generator QueueServer out in out class SingleSeverQueue : public CCoupled public: SingleSverQueue(); ~SingleServerQueue(); ; SingleServerQueue::SingleServerQueue() CModel *Gen, *QueSer; Gen = new Generator; QueSer = new QueueServer; AddComponent(2, Gen, QueSer); SetPriority(2, Gen, QueSer); AddCoupling(Gen, out", QueSer, in");...

12 DEVS Development Methodology Step 6 12 of 32 Step 6: Testing / Debugging ta : S Real d ext : Q X Q : Q Y d int : Q Q Atomic Model Interface Developer implement C++ Application program Simulation = Execution of DEVS Model = Call DEVS Functions/Relations t (x, t) L t N e (y, t) Simulator (*, t) (done, t N ) (Simulation algorithm) t L : time of last event t N : time of next event e : elapsed time Simulation Engine C++ compiler (System Environment)) System provide (Develop Environment) Simulator behavior is measurable in pre-condition and post-condition of 4 DEVS functions M l Y X d ext S d int ta R

13 Function Call Order (1/4) 13 of 32 A out in B A::OutputFn B::ExtTransFn Create Msg_Out (new) Attached User Defined Object * Msg_Out B::TimeAdvanceFn A::IntTransFn Delete Msg_Out (delete) A::TimeAdvanceFn

14 Function Call Order (2/4) 14 of 32 Attached User Defined Object * Msg_Out out in A B A::OutputFn B::ExtTransFn Create Msg_Out (new) in C B::TimeAdvanceFn C::ExtTransFn * B,C,D order may in D C::TimeAdvanceFn differ D::ExtTransFn D::TimeAdvanceFn Delete Msg_Out A::IntTransFn (delete) A::TimeAdvanceFn

15 Function Call Order (3/4) 15 of 32 Attached User Defined Object * Msg_Out A out in B C B C out A::OutputFn B::ExtTransFn D out A B B::TimeAdvanceFn Assume that A::IntTransFn A,C,D are scheduled at the same time, A::TimeAdvanceFn and the priority is C>A>D, and B s schedule is later than A,C,D D B even if B receives events. Create Msg_Out (new) Delete Msg_Out (delete)

16 Function Call Order (4/4) Attached User Defined Object * Msg_Out A::OutputFn Create(new) 16 of 32 Msg_Out, Msg_Out2 B::ExtTransFn A out1 in B B::TimeAdvanceFn Attached User Defined Object * Msg_Out2 out2 in in C D C::ExtTransFn C::TimeAdvanceFn D::ExtTransFn D::TimeAdvanceFn * B,C,D,E order may differ in E E::ExtTransFn E::TimeAdvanceFn Delete Msg_Out, A::IntTransFn Msg_Out2 A::TimeAdvanceFn

17 Auxiliary: Simulation Option 17 of 32 // CDEVSimInterface 객체생성 CDEVSimInterface* pinterface=cdevsiminterfacedefaultfactory::create(); // 전역변수로설정 SET_DEVSINTERFACE(pInterface); // 시뮬레이션옵션설정 pinterface->simoption.brealtime = true; pinterface->simoption.btimetick = 0.1; pinterface->simoption.bratio = 20; pinterface->simoption.timemode = CSimOption::MINUTE; pinterface->simoption.bmultithread = true; pinterface->simoption.busehla = false; // 시뮬레이션모델설정 delete pinterface->setmodel(new Model); // 시뮬레이션시작 pinterface->simulationstart(); // 엔진시작 pinterface->enginestart(); // 모델삭제 delete pinterface->getmodel(); pinterface->setmodel(null); // CDEVSimInterface 객체삭제 CDEVSimInterfaceDefaultFactory::destroy(pInterface);

18 Configuration using SimOption 18 of 32 멤버변수타입값의미 brealtime bool true Real-Time 으로동작. btimetick bratio double 20 TimeMode _TimeMode CSimOption::MINUT E bmultithread bool true Thread 로동작 busehla bool false 이벤트가없을경우시뮬레이션시간 0.1 씩전진. 실제시간과시뮬레이션시간이흐르는비율을같도록함. brealtime=ture 이니경우, 시뮬레이션시간 1 을실제시간에서의초로매핑. 외부 HLA/RTI 아답터등에시간진행요청및허가를받아서시뮬레이션진행.

19 DES Level Modeling: Ping-Pong-Game Example Single Ping Pong Game 19 of 32 Referee Player-A Player-B Player-A Player-B Attack Defense Attack Defense Out Out

20 Ping-Pong 시스템의요구사항 경기방법 게임은중앙에네트를친테이블의양끝에상대하는플레이어가볼을서로라켓으로번갈아가면서쳐넘긴다. 경기종류 개인전 2 명의플레이어가경기를진행한다. 득점방법및승패 서브를하면서경기시작한다. 서비스는서브권을가진측에서 2 번을서비스를한후상대플레이어에게서브권을넘긴다. 듀스상황일경우에는 1 번씩서브권을주고받는다. 플레이어가공을받아치는것은확률적으로계산한다. 득점은 1 점씩이며 11 점을먼저얻는측이승리한다. 듀스가되면계속해서 2 점을먼저얻어야승리한다. 20 of 32

21 Ping-Pong 모델링과정 실제로시스템을이루고있는구성요소파악. 심판, 플레이어 2 명, 탁구대, 탁구채, 탁구공등. 21 of 32 모델링목적에맞게시스템을추상화. 모델링목적 : 탁구경기를최대한간단하게표현. 추상화결과 심판, 플레이어 : 모델 탁구공 : 메시지 탁구대, 탁구채등은추상화결과생략. 모델사이의인터페이스정의 심판 플레이어에게서브권넘김. 플레이어 다른플레이어에게공을넘김. 심판에게공격실패를보고함. 각모델을자세하게모델링 표현하고자하는정도에따라계층구조로자세하게표현가능.

22 Ping-Pong Model 22 of 32 Ping-Pong Referee SERVA OUTA OUTB SERVB SERV_SELF SERV_OTHER SERV_OTHER SERV_SELF OUT_OTHER OUT_SELF OUT_SELF OUT_OTHER PlayerA BALL_SEND BALL_REV PlayerB BALL_REV BALL_SEND

23 Atomic DEVS Model for Ping-Pong Player 23 of 32 Model Player SERV_SELF SERV_OTHER?BALL_SEND BALL_SEND OUT_SELF BALL_REV OUT_OTHER [rand_num<m_prob] [rand_num>m_prob]?serv_other?out_other State Variable m_prob rand_num

24 Atomic DEVS Model for Ping-Pong Referee 24 of 32 Model Referee OUTA OUTB?OUTA or?outb SERVA SERVB [m_servf = 1]!SERVB [m_servf = 0] [m_endf = true] State Variable m_scorea m_scoreb m_servf m_endf

25 CPlayer Class (1/2) 25 of 32 class CPlayer : public CAtomic public: CPlayer(); CPlayer(const char* name); virtual ~CPlayer(); virtual bool ExtTransFn(const CMessage &); virtual bool IntTransFn(); virtual bool OutputFn(CMessage &); virtual TimeType TimeAdvanceFn(); public: enum PLAYER_STATE DEFENSE = 0, ATTACK = 1, SERVE = 2 ; protected: PLAYER_STATE m_state; double m_prob; double rand_num; ;

26 CPlayer Class (2/2) 26 of 32 CPlayer::CPlayer(String name, double prob) : m_state(serve), m_prob(prob) m_name = name; SetName(m_Name); AddInPorts(4, "BALL_REV", "OUT_OTHER", "SERV_SELF", "SERV_OTHER"); AddOutPorts(2, "BALL_SEND", "OUT_SELF");

27 CPlayer s External Transition Function 27 of 32 External Transition Function (SERVE, SERV_SELF) ATTACK (SERVE, SERV_OTHER) DEFENSE (DEFENSE, BALL_REV) ATTACK (DEFENSE, OUT_OTHER) SERVE bool CPlayer::ExtTransFn(const CMessage& message) if(m_state == SERVE && message.getport() == "SERV_SELF ) m_state = ATTACK; else if(m_state == SERVE && message.getport() == "SERV_OTHER ) m_state = DEFENSE; else if( m_state == DEFENSE && message.getport() == BALL_REV ) m_state = ATTACK; else if(m_state == DEFENSE && message.getport() == "OUT_OTHER") m_state = SERVE; else return false; return true;

28 CPlayer s Internal Transition Function 28 of 32 Internal Transition Function ATTACK DEFENSE if(m_prob > rand_num ) ATTACK SERVE if(m_prob< rand_num ) bool CPlayer::IntTransFn() if( m_state == ATTACK ) if( m_prob > rand_num ) m_state = DEFENSE; else m_state = SERVE; else return false; return true;

29 CPlayer s Output Function 29 of 32 Output Function ATTACK BALL_SEND if(m_prob > rand_num ) ATTACK OUT_SELF if(m_prob< rand_num ) bool CPlayer::OutputFn(CMessage & message) rand_num = CRandom::Random((unsigned)time(NULL) % ); if( m_state == ATTACK ) if( m_prob > rand_num ) message.setportvalue("ball_send", NULL); else message.setportvalue("out_self", NULL); else return false; return true;

30 CPlayer s Time Advance Function 30 of 32 Time Advance Function ATTACK ATTACK_TIME, SERVE, DEFENSE Infinity TimeType CPlayer::TimeAdvanceFn() if( m_state == ATTACK) return ATTACK_TIME; else return Infinity;

31 Class of CSingleMatch Coupled Model (1/2) 31 of 32 class CSingleMatch : public CCoupled public: CPlayer *player1, *player2; CReferee *referee; CSingleMatch(double prob_a, double prob_b, int first_serv); ~CSingleMatch(); ; PingPong Referee SERVA OUTA OUTB SERVB SERV_SELF SERV_OTHER SERV_OTHER SERV_SELF OUT_OTHER OUT_SELF OUT_SELF OUT_OTHER PlayerA BALL_SEND BALL_REV PlayerB BALL_REV BALL_SEND

32 Class of CSingleMatch Coupled Model (2/2) 32 of 32 CSingleMatch::CSingleMatch(double prob_a, double prob_b, int first_serv) SetName("SingleMatch"); player1 = new CPlayer("A", prob_a); player2 = new CPlayer("B", prob_b); referee = new CReferee("R", first_serv); AddComponent(3, player1, player2, referee); AddCoupling(player1, "BALL_SEND", player2, "BALL_REV"); AddCoupling(player1, "OUT_SELF", player2, "OUT_OTHER"); AddCoupling(player1, "OUT_SELF", referee, "OUTA"); AddCoupling(player2, "BALL_SEND", player1, "BALL_REV"); AddCoupling(player2, "OUT_SELF", player1, "OUT_OTHER"); AddCoupling(player2, "OUT_SELF", referee, "OUTB"); AddCoupling(referee, "SERVA", player1, "SERV_SELF"); AddCoupling(referee, "SERVA", player2, "SERV_OTHER"); AddCoupling(referee, "SERVB", player1, "SERV_OTHER"); AddCoupling(referee, "SERVB", player2, "SERV_SELF"); SetPriority(3, referee, player1, player2);