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‫‌های‌پت‬‫ه‬‫شبک‬‫ری‬
‫معرفی‬
•‫شده‬ ‫توزیع‬ ‫های‬‫سیستم‬ ‫سازی‬‫مدل‬ ‫زبان‬
•‫نمایش‬ ‫برای‬ ‫گرافیکی‬ ‫مدل‬ ‫دارای‬
•‫در‬ ‫پتری‬ ‫آدام‬ ‫کارل‬۱۹۳۹
•‫شیمیایی‬ ‫های‬‫فرایند‬
Mahdi Dolati Verification of Reactive Systems 2
‫مدل‬ ‫استاتیک‬
•‫دار‬‫وزن‬ ‫بخشی‬ ‫دو‬ ‫و‬ ‫دار‬‫جهت‬ ‫گراف‬ ‫یک‬
Mahdi Dolati Verification of Reactive Systems 3
‫مدل‬ ‫استاتیک‬
•‫پتری‬ ‫ی‬‫شبکه‬
•‫مکان‬
•‫انتقال‬
Mahdi Dolati Verification of Reactive Systems 4
‫مدل‬ ‫استاتیک‬
•‫شده‬ ‫گذاری‬‫نشان‬ ‫پتری‬ ‫ی‬‫شبکه‬
•‫توکن‬
Mahdi Dolati Verification of Reactive Systems 5
‫مدل‬ ‫استاتیک‬
•‫شده‬ ‫گذاری‬‫نشان‬ ‫پتری‬ ‫ی‬‫شبکه‬
M0 = (0, 1, 1)
Mahdi Dolati Verification of Reactive Systems 6
‫مدل‬ ‫استاتیک‬ ‫رسمی‬ ‫بیان‬
•‫ی‬‫شبکه‬N = (P, T, F)
•‫های‬‫مکان‬ ‫ی‬‫مجموعه‬P‫های‬‫انتقال‬ ‫و‬T‫که‬𝑃 ∩ 𝑇 = ϕ
•‫های‬‫یال‬ ‫مجموعه‬F‫که‬𝐹 ⊆ 𝑃 × 𝑇 ∪ 𝑇 × 𝑃
•‫پتری‬ ‫ی‬‫شبکه‬PN = (N, M, W)
•N‫است‬ ‫شبکه‬ ‫یک‬
•𝑀: 𝑃 → ℕ‫مکان‬ ‫هر‬ ‫توکن‬ ‫تعداد‬
•𝑊: 𝐹 → ℕ‫یال‬ ‫هر‬ ‫وزن‬
Mahdi Dolati Verification of Reactive Systems 7
‫مدل‬ ‫رفتار‬
•‫فعال‬ ‫های‬‫انتقال‬
•‫شرط‬ ،‫ها‬‫محل‬–‫ها‬‫رخداد‬ ،‫ها‬‫انتقال‬
Mahdi Dolati Verification of Reactive Systems 8
‫مدل‬ ‫رفتار‬
•‫انتقال‬ ‫یک‬ ‫کردن‬ ‫عمل‬
•‫غیرقطعی‬
Mahdi Dolati Verification of Reactive Systems 9
‫مدل‬ ‫رفتار‬
•‫انتقال‬ ‫یک‬ ‫کردن‬ ‫عمل‬
•‫غیرقطعی‬
Mahdi Dolati Verification of Reactive Systems 10
‫مدل‬ ‫رفتار‬ ‫رسمی‬ ‫بیان‬
•‫انتقال‬ ‫برای‬t
• 𝑡− 𝑝 =
𝑊 𝑝, 𝑡 , 𝑖𝑓𝑓 𝑝, 𝑡 ∈ 𝐹
0 , 𝑖𝑓𝑓 𝑝, 𝑡 ∉ 𝐹
• 𝑡+ 𝑝 =
𝑊 𝑡, 𝑝 , 𝑖𝑓𝑓 𝑡, 𝑝 ∈ 𝐹
0 , 𝑖𝑓𝑓 𝑡, 𝑝 ∉ 𝐹
p t
pt
W(p, t)
W(p, t)
Mahdi Dolati Verification of Reactive Systems 11
‫رسمی‬ ‫بیان‬‫مدل‬ ‫رفتار‬
•‫انتقال‬t‫است‬ ‫فعال‬
• ∀𝑝: 𝑃 ∙ 𝑡−
𝑝 ≤ 𝑀 𝑝
•‫انتقال‬t‫کند‬‫می‬ ‫عمل‬
• ∀𝑝: 𝑃 ∙ 𝑀′
𝑝 = 𝑀 𝑝 − 𝑡−
𝑝 + 𝑡+
𝑝
•‫با‬𝑀 →
𝑡
𝑀′‫دهیم‬‫می‬ ‫نشان‬
Mahdi Dolati Verification of Reactive Systems 12
‫عملیاتی‬ ‫معنای‬
•‫گام‬ ‫یک‬ ‫در‬ ‫پذیری‬‫دسترس‬𝑀 →
𝑡
𝑀′
•‫پذیری‬‫دسترس‬𝑀 →∗
𝑀′
(‫متعدی‬ ‫بازتابی‬ ‫بستار‬→
𝑡
)
• 𝑅 𝑁 ≜ {𝑀′
|𝑀0 →∗
𝑀′
}
•‫ی‬‫رابطه‬→
𝑡
‫روی‬ ‫بر‬ ‫شده‬ ‫محدود‬𝑅 𝑁
•‫حالت‬ ‫فضای‬
Mahdi Dolati Verification of Reactive Systems 13
‫عملیاتی‬ ‫معنای‬(‫مثال‬)
Mahdi Dolati Verification of Reactive Systems 14
‫ریاضیاتی‬ ‫های‬‫ویژگی‬
•‫باال‬ ‫پذیری‬ ‫تحلیل‬
•‫ها‬‫ویژگی‬ ‫از‬ ‫بسیاری‬ ‫اتوماتیک‬ ‫تعیین‬
•‫پذیری‬‫دسترس‬
•‫بودن‬ ‫زنده‬
•‫داری‬‫کران‬
•‫بست‬‫بن‬
Mahdi Dolati Verification of Reactive Systems 15
‫پذیری‬‫دسترس‬
•‫صحت‬ ‫تعیین‬𝑀 ∈ 𝑅(𝑁)
•‫نمایی‬ ‫فضایی‬ ‫پیچیدگی‬[L76]
•‫خطادار‬ ‫های‬‫حالت‬ ‫کردن‬ ‫پیدا‬
•‫دارد‬ ‫ادامه‬ ‫ی‬‫بهینه‬ ‫ی‬‫محاسبه‬ ‫برای‬ ‫تحقیقات‬
•‫دیگر‬ ‫های‬‫روش‬
Mahdi Dolati Verification of Reactive Systems 16
‫بودن‬ ‫زنده‬
•‫عمل‬ ‫توالی‬
•‫گراف‬ ‫در‬G
•‫اولیه‬ ‫گذاری‬‫نشان‬ ‫با‬M0
•𝜎 = 𝑡𝑖1 … 𝑡𝑖𝑛
•𝑀0 → 𝐺,𝑡 𝑖1
𝑀1 … 𝑀 𝑛−1 → 𝐺,𝑡 𝑖𝑛
𝑀 𝑛
•‫عمل‬ ‫های‬‫توالی‬ ‫تمام‬ ‫مجموعه‬
•L(N)
Mahdi Dolati Verification of Reactive Systems 17
‫بودن‬ ‫زنده‬
•‫انتقال‬ ‫یک‬
•‫مرده‬:‫نکند‬ ‫عمل‬ ‫توالی‬ ‫هیچ‬ ‫در‬
•L1-‫زنده‬:‫باشد‬ ‫ممکن‬ ‫آن‬ ‫رخداد‬
•‫دارد‬ ‫وجود‬ ‫عمل‬ ‫های‬‫توالی‬ ‫از‬ ‫بعضی‬ ‫در‬
•L2-‫زنده‬:‫دلخواه‬ ‫صورت‬ ‫به‬ ‫ها‬‫بار‬
•‫حداقل‬k‫های‬‫توالی‬ ‫بعضی‬ ‫در‬ ‫بار‬‫وجود‬ ‫عمل‬‫دارد‬
•L3-‫زنده‬:‫نامحدود‬ ‫صورت‬ ‫به‬ ‫بارها‬
•‫حداقل‬k‫بعضی‬ ‫در‬ ‫بار‬‫پیشوندی‬ ‫ی‬‫زیرمجموعه‬ ‫یک‬ ‫اعضای‬-‫توال‬ ‫بسته‬‫ها‬‫ی‬
•L4-‫زنده‬:‫کند‬ ‫عمل‬ ‫همیشه‬
•L1-‫زنده‬‫ممکن‬ ‫های‬‫گذاری‬‫نشان‬ ‫تمام‬ ‫در‬
Mahdi Dolati Verification of Reactive Systems 18
‫داری‬‫کران‬
•‫محدود‬ ‫ها‬‫توکن‬ ‫تعداد‬ ‫ممکن‬ ‫های‬‫گذاری‬‫نشان‬ ‫تمام‬ ‫در‬ ‫اگر‬
‫باشد‬
•‫استفاده‬:‫بافر‬ ‫سرریز‬ ،‫محدود‬ ‫منابع‬
•‫اگر‬ ‫تنها‬ ‫و‬ ‫اگر‬ ‫دار‬‫کران‬‫گراف‬‫محدود‬ ‫پذیری‬‫دسترس‬
•‫دار‬‫ظرفیت‬ ‫های‬‫محل‬ ‫با‬ ‫پتری‬ ‫ی‬‫شبکه‬ ‫گسترش‬
Mahdi Dolati Verification of Reactive Systems 19
‫پتری‬ ‫ی‬‫شبکه‬ ‫مثال‬
Mahdi Dolati Verification of Reactive Systems 20
‫ها‬‫افزونه‬
•‫یال‬ ‫مختلف‬ ‫انواع‬
•‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
•‫رنگی‬ ‫پتری‬ ‫ی‬‫شبکه‬
Mahdi Dolati Verification of Reactive Systems 21
‫یال‬ ‫مختلف‬ ‫انواع‬
•‫ریست‬
(1, 1, 0, 5) →
𝒕𝟐
…
Mahdi Dolati Verification of Reactive Systems 22
‫یال‬ ‫مختلف‬ ‫انواع‬
•‫ریست‬
(1, 1, 0, 5) →
𝒕𝟐
(𝟏, 𝟎, 𝟏, 𝟎)
Mahdi Dolati Verification of Reactive Systems 23
‫یال‬ ‫مختلف‬ ‫انواع‬
•‫خواندن‬
(1, 1, 0, 1) →
𝒕𝟐
…
Mahdi Dolati Verification of Reactive Systems 24
‫یال‬ ‫مختلف‬ ‫انواع‬
•‫خواندن‬
(1, 1, 0, 1) →
𝒕𝟐
(1, 0, 1, 0)
Mahdi Dolati Verification of Reactive Systems 25
‫یال‬ ‫مختلف‬ ‫انواع‬
•‫بازدارنده‬
t1‫اگر‬ ‫تنها‬ ‫و‬ ‫اگر‬ ‫است‬ ‫شده‬ ‫بازداشته‬M(P3) ≥ 1‫یا‬M(P4) ≥ 1
Mahdi Dolati Verification of Reactive Systems 26
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
•‫پتری‬ ‫های‬‫شبکه‬ ‫مختلف‬ ‫های‬‫بخش‬ ‫در‬ ‫زمانی‬ ‫توصیف‬
•‫ها‬‫انتقال‬
•‫ها‬‫مکان‬
•‫ها‬‫یال‬
•‫ها‬‫توکن‬
•‫غیرقطعی‬ ‫صورت‬ ‫به‬ ‫زمان‬ ‫گذر‬
Mahdi Dolati Verification of Reactive Systems 27
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
•‫پتری‬ ‫های‬‫شبکه‬ ‫قدرت‬‫کمتر‬‫تورینگ‬ ‫ماشین‬ ‫قدرت‬ ‫از‬
‫است‬.[P13]
•‫دار‬‫زمان‬ ‫پتری‬ ‫های‬‫شبکه‬ ‫قدرت‬‫معادل‬‫تورینگ‬ ‫ماشین‬
‫است‬.[P08]
Mahdi Dolati Verification of Reactive Systems 28
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
at‫و‬ ‫زمان‬ ‫زودترین‬bt‫زمانی‬ ‫دیرترین‬(‫شدن‬ ‫فعال‬ ‫از‬ ‫بعد‬)
‫کند‬ ‫عمل‬ ‫تواند‬ ‫می‬ ‫انتقال‬ ‫که‬ ‫است‬
Mahdi Dolati Verification of Reactive Systems 29
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
•‫مکانی‬ ‫گذاری‬‫نشان‬
•m0 = (2, 0, 1)
•‫زمانی‬ ‫گذاری‬‫نشان‬
•‫شده‬ ‫فعال‬ ‫انتقال‬ ‫که‬ ‫باری‬ ‫آخرین‬ ‫از‬ ‫زمان‬ ‫نمایش‬
•h0 = (#, 0, 0, 0)
Mahdi Dolati Verification of Reactive Systems 30
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
•‫شبکه‬ ‫این‬ ‫در‬ ‫حالت‬z = (m, h)
•m‫مکانی‬ ‫گذاری‬‫نشان‬ ‫یک‬
•h‫زمانی‬ ‫گذاری‬‫نشان‬ ‫یک‬
•‫به‬ ‫حالت‬ ‫تغییر‬z’ = (m’, h’)
•‫انتقال‬ ‫یک‬ ‫شدن‬ ‫فعال‬𝑧 →
𝑡
𝑧′
•‫زمان‬ ‫گذشت‬𝑧 →
𝜏
𝑧′
Mahdi Dolati Verification of Reactive Systems 31
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
Mahdi Dolati Verification of Reactive Systems 32
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
Mahdi Dolati Verification of Reactive Systems 33
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
Mahdi Dolati Verification of Reactive Systems 34
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
Mahdi Dolati Verification of Reactive Systems 35
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
Mahdi Dolati Verification of Reactive Systems 36
‫دار‬‫زمان‬ ‫پتری‬ ‫ی‬‫شبکه‬
Mahdi Dolati Verification of Reactive Systems 37
‫تشکر‬ ‫با‬!
‫پرسش؟‬
Mahdi Dolati Verification of Reactive Systems 38
‫منابع‬
• [P08] Prof. Louchka Popova-Zeugmann, “Time Petri Nets:
Theory, Tools and Applications Part I”, Humboldt-Universität zu
Berlin, Course Lecture
• Prof. Morgan Magnin, “Computational Approaches to Analyze
Complex Dynamic Systems : Model-Checking and its
Applications”, NII International advanced lectures series on ICT:
series of 4 lectures of 2 hours in Spring 2013 at National
Institute of Informatics, , Tōkyō, Japan
• http://en.wikipedia.org/wiki/Petri_net
Mahdi Dolati Verification of Reactive Systems 39
‫ارجاعات‬
• [L76] Lipton, R. “The Reachability Problem
Requires Exponential Space”, Technical Report 62,
Yale University, 1976
• [P13] Louchka Popova-Zeugmann, “Time and Petri
Nets”, Springer, Chapter 2, 2013
Mahdi Dolati Verification of Reactive Systems 40

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