High Integrity Software

4. 3 The Gypsy language 72 4. 4 The Gypsy Verification Environment 73 4. 5 A simple example 81 4. 6 Specification data types 91 4. 7 Future directions 95 100 4. 8 Conclusions 5 Reliable programming in standard languages 102 Bernard Carre, Program Validation Ltd. 5. 1 Introduction 102 5. 2 Language requirements for high-integrity programming 103 5. 3 The use of standard languages 108 5. 4 Programming in Pascal and Ada 110 1'19 5. 5 Practical experiences NewSpeak: a reliable programming language 6 122 I. F. Currie, Royal Signals and Radar Establishment 6. 1 Introduction 122 6. 2 Types and values 127 6. 3 Declarations and variables 132 6. 4 Guarded declarations 134 6. 5 Cases and conditionals 136 6. 6 Loops 138 6. 7 Procedures 140 6. 8 Assertions 145 6. 9 Timing 147 6. 10 Conclusion 149 6. 11 Appendix 1: summary of syntax 150 6. 12 Appendix 2: type lattice and widening 156 7 Program analysis and systematic testing 159 M. A. Hennell, University of Liverpool, and D. Hedley and I. J. Riddell, Liverpool Data Research Associates Ltd. 7. 1 Introduction 159 7. 2 The basic requirement 160 7. 3 The Liverpool experience 161 7. 4 The Liverpool experiments 162 7. 5 The LDRA Testbeds 163 Interpretation 169 7. 6 7. 7 Applicability and benefits 171 7. 8 Safety-critical systems 173 VI 8 Program analysis and verification 176 Bernard Carre, Program Validation Ltd. 8. 1 Introduction 176 8.

Within 50 years computers could have capabilities rivaling that of the human brain. Effective utilization of such new technologies poses a significant challenge to the computer science community, which finds an ever increasing number of complex applications within its technological grasp. In addition to increased complexity, most, if not all, of these applications are also accompanied by an inherent increase in the consequences associated with their failure, resulting in the construction of increasingly high consequence complex systems. Systems that fall within this domain are beyond the ability to construct in a brute force manner. There are two major challenges in developing such systems: manage complexity and provide sufficient evidence that the system satisfies dependability constraints. Society is tacitly relying on the research community to solve these problems on a timetable satisfying the needs of industry. While impressive results have been obtained, the research community is still, to some extent, hamstrung by the lack of realistic case study problems against which to benchmark new techniques and approaches. The purpose of High Integrity Software is to explore a cross-section of some of the most promising areas of research in the construction of high consequence complex systems, for example, a case study involving the Bay Area Rapid Transit (BART) system. Because of its scope and complexity, the BART case study is being recognized by many in the formal methods community as one of the definitive case study problems, and as such provides a valuable insight into the challenges that must be faced in the upcoming years. High Integrity Software is suitable as a secondary text for a graduate level course, and as a reference for researchers and practitioners in industry.

This is the first introduction to the SPARK 2014 language and the tools to verify programs for safety- and security-critical applications.

The second half of the twentieth century has witnessed remarkable advances in technology. The unquestioned leader in this race has been computer technology. Even the most modest personal computers today have computing power that would have astounded the leading technol ogists a few decades earlier, and what's more, similar advances are pre dicted for many years to come. Looking towards the future, it has been conservatively estimated that in 2047 computers could easily be 100,000 times more powerful than they were in 1997 (Moore's law [Moore] would lead to an increase on the order of around 10 billion) [Bell]. Because of its enormous capability, computer technology is becoming pervasive across the technology spectrum. Nowadays it is not surpris ing to discover that very common household gadgets like your toaster contain computer technology. Televisions, microwave ovens, and even electric shavers contain software. And what's more, the use of computer technology has been estimated to double every two years [Gibbs]. In order to keep up with the growing technology demands and to fully utilize the ever more powerful computing platforms, software projects have become more and more ambitious. This has lead to software systems becoming dominant forces in system functionality. Further more, the ambition to realize significant portions of a system's function ality through software has extended into the high consequence realm. Presently, software controls many critical functions in (1) airplanes, (2) electronic commerce, (3) space-bound systems, (4) medical systems, and (5) various transportation systems such as automobiles and trains.

This pack introduces the SPARK language and its associated tools and teaches the principles of writing safety-critical software using SPARK, a subset of the Ada 95 language. SPARK was specifically developed to serve industries developing high-integrity, safety-critical software with a language and associated toolset which increase the likelihood of the program behaving as intended.

This book provides an accessible introduction to the SPARK programming language. Updated 'classic' that covers all of the new features of SPARK, including Object Oriented Programming. The only book on the market that covers this important and robust programming language. CD-ROM contains the main SPARK tools and additional manuals giving all the information needed to use SPARK in practice. Technology: The SPARK language is aimed at writing reliable software that combines simplicity and rigour within a practical framework. Because of this, many safety-critical, high integrity systems are developed using SPARK. User Level: Intermediate Audience: Software engineers, programmers, technical leaders, software managers. Engineering companies in fields such as avionics, railroads, medical instrumentation and automobiles. Academics giving MSc courses in Safety Critical Systems Engineering, System Safety Engineering, Software Engineering. Author Biography: John Barnes is a veteran of the computing industry. In 1977 he designed and implemented the RTL/2 programming language and was an original member of the ADA programming language design team. He was founder and MD of Alsys Ltd from 1985 to 1991. Currently self employed, John is the author of 'Programming in ADA' which has sold 150000 copies and been translated into 6 languages.

This important and timely book contains vital information for all developers working with C, whether in high-integrity areas or not, who need to produce reliable and effective software.

"It's about time that a practicing engineer with casting and academic experience has written a book that provides answers to questions about squeeze casting and semi-solid molding/forming that many engineers and students of casting need answered." —Joseph C. Benedyk, PhD, Consultant and retired technical director, Alcoa High Integrity Die Casting Processes provides a comprehensive look at the concepts behind advanced die casting technologies, including vacuum die casting, squeeze casting, and several variants of semi-solid metalworking. Practical applications for these processes are illustrated in numerous case studies. This single-source reference tool presents the latest material in five sections: Basic concepts of die casting and molten metal flow High integrity die casting processes with case studies Product design considerations Controlling quality and avoiding defects Future advances under development Key coverage includes a survey of liquid metal flow, strategies to overcome the limitations of conventional die casting, and potential defects unique to high integrity die casting processes. Also featured are methods for minimizing porosity, reducing cost by design, practical applied statistical process control techniques, designing for manufacturability, and containment methods for potential processing defects. Several chapters present detailed real-world examples illustrating the broad range of applications possible using high integrity die casting processes. Included with this book is a CD-ROM containing PowerPoint(r) presentations for each chapter. These presentations can be used for training purposes in conjunction with numerous study questions designed to practically apply the content of the book to real-world situations. Selected PowerPoint(r) slides can be used to support engineering proposals, marketing presentations, or customer education seminars. High Integrity Die Casting Processes is a valuable reference for both component producers and component users alike. Process engineers, tool designers, manufacturing engineers, production managers, and machine operators will acquire a better understanding of these advanced die casting processes to optimize manufacturing and improve product quality. Component designers, product engineers, purchasing agents, buyers, supplier quality engineers, and project managers will gain insight into these processes and develop superior products by design.