TAILIEUCHUNG - Model-Based Design for Embedded Systems- P17

Model-Based Design for Embedded Systems- P17:The unparalleled flexibility of computation has been a key driver and feature bonanza in the development of a wide range of products across a broad and diverse spectrum of applications such as in the automotive aerospace, health care, consumer electronics, etc. | 456 Model-Based Design for Embedded Systems Derived Functions and Logic Programs A query reduces some property of a model to a boolean value Either the property holds the query is satisfied or it does not hold. Sometimes this reduction loses information that should persist. For example suppose we want to know which states can be reached after one two and three FIGURE Calculating reachable states from initial state 0. transitions of a FSM as shown in Figure . This can be done with the queries shown in Figure . Notice that the query findTwo which finds all states after two steps must first discover all the states one step away. Similarly the findThree query must find the states reachable in one and two steps before finding the states reachable in three steps. The Nth find query does all the work of the N 1 previous queries which is wasteful and makes the queries unnecessarily verbose. This problem can be solved by temporarily storing the results of queries into data structures. These temporary results are created using derived functions. A derived function is a function beginning with a lowercase letter. Derived functions are only used to temporarily remember some intermediate results and can never appear in the data elements of an input model. For example reachl state State . declares a derived function for remembering those states reachable from an initial state after one step. Temporary results are created by writing the following expression reachl y x is Initial y is State t is Transition y. Queries searching for reachable states 3. findOne x is Initial y is State 4. t is Transition 5. y. 7. findtwo x is Initial y is State 8. t is Transition s is Transition 9. y. 11. findThree x is Initial y is State 12. t is Transition s is Transition u is Transition 13. 14. y. FIGURE Queries for .

TAILIEUCHUNG - Chia sẻ tài liệu không giới hạn
Địa chỉ : 444 Hoang Hoa Tham, Hanoi, Viet Nam
Website : tailieuchung.com
Email : tailieuchung20@gmail.com
Tailieuchung.com là thư viện tài liệu trực tuyến, nơi chia sẽ trao đổi hàng triệu tài liệu như luận văn đồ án, sách, giáo trình, đề thi.
Chúng tôi không chịu trách nhiệm liên quan đến các vấn đề bản quyền nội dung tài liệu được thành viên tự nguyện đăng tải lên, nếu phát hiện thấy tài liệu xấu hoặc tài liệu có bản quyền xin hãy email cho chúng tôi.
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.