As computers increasingly control the systems and services we depend upon within our daily lives like transport, communications, and the media, ensuring these systems function correctly is of utmost importance. This book consists of twelve chapters and one historical account that were presented at a workshop in London in 2015, marking the 25th anniversary of the European ESPRIT Basic Research project ‘ProCoS’ (Provably Correct Systems). The ProCoS I and II projects pioneered and accelerated the automation of verification techniques, resulting in a wide range of applications within many trades and sectors such as aerospace, electronics, communications, and retail. The following topics are covered: An historical account of the ProCoS project Hybrid Systems Correctness of Concurrent Algorithms Interfaces and Linking Automatic Verification Run-time Assertions Checking Formal and Semi-Formal Methods Provably Correct Systems provides researchers, designers and engineers with a complete overview of the ProCoS initiative, past and present, and explores current developments and perspectives within the field.

Computers are gaining more and more control over systems that we use or rely on in our daily lives, privately as well as professionally. In safety-critical applications, as well as in others, it is of paramount importance that systems controled by a computer or computing systems themselves reliably behave in accordance with the specification and requirements, in other words: here correctness of the system, of its software and hardware is crucial. In order to cope with this callenge, software engineers and computer scientists need to understand the foundations of programming, how different formal theories are linked together, how compilers correctly translate high-level programs into machine code, and why transformations performed are justifiable. This book presents 17 mutually reviewed invited papers organized in sections on methodology, programming, automation, compilation, and application.

Presenting a theory of the theoryless, a computer scientist provides a model of how effective behavior can be learned even in a world as complex as our own, shedding new light on human nature.

As the complexity of embedded computer-controlled systems increases, the present industrial practice for their development gives cause for concern, especially for safety-critical applications where human lives are at stake. The use of software in such systems has increased enormously in the last decade. Formal methods, based on firm mathematical foundations, provide one means to help with reducing the risk of introducing errors during specification and development. There is currently much interest in both academic and industrial circles concerning the issues involved, but the techniques still need further investigation and promulgation to make their widespread use a reality. This book presents results of research into techniques to aid the formal verification of mixed hardware/software systems. Aspects of system specification and verification from requirements down to the underlying hardware are addressed, with particular regard to real-time issues. The work presented is largely based around the Occam programming language and Transputer microprocessor paradigm. The HOL theorem prover, based on higher order logic, has mainly been used in the application of machine-checked proofs. The book describes research work undertaken on the collaborative UK DTI/SERC-funded Information Engineering Dictorate Safemos project. The partners were Inmos Ltd., Cambridge SRI, the Oxford University Computing Laboratory and the University of Cambridge Computer Laboratory, who investigated the problems of formally verifying embedded systems. The most important results of the project are presented in the form of a series of interrelated chapters by project members and associated personnel. In addition, overviews of two other ventures with similar objectives are included as appendices. The material in this book is intended for computing science researchers and advanced industrial practitioners interested in the application of formal methods to real-time safety-critical systems at all levels of abstraction from requirements to hardware. In addition, material of a more general nature is presented, which may be of interest to managers in charge of projects applying formal methods, especially for safety-critical-systems, and others who are considering their use.

This book is the combined proceedings of the latest IFIP Formal Description Techniques (FDTs) and Protocol Specification, Testing and Verification (PSTV) series. It addresses FDTs applicable to communication protocols and distributed systems, with special emphasis on standardised FDTs. It features state-of-the-art in theory, application, tools and industrialisation of formal description.

Errata, detected in Taylor's Logarithms. London: 4to, 1792. [sic] 14.18.3 6 Kk Co-sine of 3398 3298 - Nautical Almanac (1832) In the list of ERRATA detected in Taylor's Logarithms, for cos. 4° 18'3", read cos. 14° 18'2". - Nautical Almanac (1833) ERRATUM ofthe ERRATUM ofthe ERRATA of TAYLOR'S Logarithms. For cos. 4° 18'3", read cos. 14° 18' 3". - Nautical Almanac (1836) In the 1820s, an Englishman named Charles Babbage designed and partly built a calculating machine originally intended for use in deriving and printing logarithmic and other tables used in the shipping industry. At that time, such tables were often inaccurate, copied carelessly, and had been instrumental in causing a number of maritime disasters. Babbage's machine, called a 'Difference Engine' because it performed its cal culations using the principle of partial differences, was intended to substantially reduce the number of errors made by humans calculating the tables. Babbage had also designed (but never built) a forerunner of the modern printer, which would also reduce the number of errors admitted during the transcription of the results. Nowadays, a system implemented to perform the function of Babbage's engine would be classed as safety-critical. That is, the failure of the system to produce correct results could result in the loss of human life, mass destruction of property (in the form of ships and cargo) as well as financial losses and loss of competitive advantage for the shipping firm.