Real-Time UNIX® Systems


Book Description

A growing concern of mine has been the unrealistic expectations for new computer-related technologies introduced into all kinds of organizations. Unrealistic expectations lead to disappointment, and a schizophrenic approach to the introduction of new technologies. The UNIX and real-time UNIX operating system technologies are major examples of emerging technologies with great potential benefits but unrealistic expectations. Users want to use UNIX as a common operating system throughout large segments of their organizations. A common operating system would decrease software costs by helping to provide portability and interoperability between computer systems in today's multivendor environments. Users would be able to more easily purchase new equipment and technologies and cost-effectively reuse their applications. And they could more easily connect heterogeneous equipment in different departments without having to constantly write and rewrite interfaces. On the other hand, many users in various organizations do not understand the ramifications of general-purpose versus real-time UNIX. Users tend to think of "real-time" as a way to handle exotic heart-monitoring or robotics systems. Then these users use UNIX for transaction processing and office applications and complain about its performance, robustness, and reliability. Unfortunately, the users don't realize that real-time capabilities added to UNIX can provide better performance, robustness and reliability for these non-real-time applications. Many other vendors and users do realize this, however. There are indications even now that general-purpose UNIX will go away as a separate entity. It will be replaced by a real-time UNIX. General-purpose UNIX will exist only as a subset of real-time UNIX.




Real-Time UNIX® Systems


Book Description

A growing concern of mine has been the unrealistic expectations for new computer-related technologies introduced into all kinds of organizations. Unrealistic expectations lead to disappointment, and a schizophrenic approach to the introduction of new technologies. The UNIX and real-time UNIX operating system technologies are major examples of emerging technologies with great potential benefits but unrealistic expectations. Users want to use UNIX as a common operating system throughout large segments of their organizations. A common operating system would decrease software costs by helping to provide portability and interoperability between computer systems in today's multivendor environments. Users would be able to more easily purchase new equipment and technologies and cost-effectively reuse their applications. And they could more easily connect heterogeneous equipment in different departments without having to constantly write and rewrite interfaces. On the other hand, many users in various organizations do not understand the ramifications of general-purpose versus real-time UNIX. Users tend to think of "real-time" as a way to handle exotic heart-monitoring or robotics systems. Then these users use UNIX for transaction processing and office applications and complain about its performance, robustness, and reliability. Unfortunately, the users don't realize that real-time capabilities added to UNIX can provide better performance, robustness and reliability for these non-real-time applications. Many other vendors and users do realize this, however. There are indications even now that general-purpose UNIX will go away as a separate entity. It will be replaced by a real-time UNIX. General-purpose UNIX will exist only as a subset of real-time UNIX.







Real-Time Systems Design and Analysis


Book Description

The leading guide to real-time systems design-revised and updated This third edition of Phillip Laplante's bestselling, practical guide to building real-time systems maintains its predecessors' unique holistic, systems-based approach devised to help engineers write problem-solving software. Dr. Laplante incorporates a survey of related technologies and their histories, complete with time-saving practical tips, hands-on instructions, C code, and insights into decreasing ramp-up times. Real-Time Systems Design and Analysis, Third Edition is essential for students and practicing software engineers who want improved designs, faster computation, and ultimate cost savings. Chapters discuss hardware considerations and software requirements, software systems design, the software production process, performance estimation and optimization, and engineering considerations. This new edition has been revised to include: * Up-to-date information on object-oriented technologies for real-time including object-oriented analysis, design, and languages such as Java, C++, and C# * Coverage of significant developments in the field, such as: New life-cycle methodologies and advanced programming practices for real-time, including Agile methodologies Analysis techniques for commercial real-time operating system technology Hardware advances, including field-programmable gate arrays and memory technology * Deeper coverage of: Scheduling and rate-monotonic theories Synchronization and communication techniques Software testing and metrics Real-Time Systems Design and Analysis, Third Edition remains an unmatched resource for students and practicing software engineers who want improved designs, faster computation, and ultimate cost savings.




Real-Time Database Systems


Book Description

In recent years, tremendous research has been devoted to the design of database systems for real-time applications, called real-time database systems (RTDBS), where transactions are associated with deadlines on their completion times, and some of the data objects in the database are associated with temporal constraints on their validity. Examples of important applications of RTDBS include stock trading systems, navigation systems and computer integrated manufacturing. Different transaction scheduling algorithms and concurrency control protocols have been proposed to satisfy transaction timing data temporal constraints. Other design issues important to the performance of a RTDBS are buffer management, index accesses and I/O scheduling. Real-Time Database Systems: Architecture and Techniques summarizes important research results in this area, and serves as an excellent reference for practitioners, researchers and educators of real-time systems and database systems.




Real Time Computing


Book Description

NATO's Division of Scientific and Environmental Affairs sponsored this Advan ced Study Institute because it was felt to be timely to cover this important and challengjng subject for the first time in the framework of NATO's ASI programme. The significance of real-time systems in everyones' life is rapidly growing. The vast spectrum of these systems can be characterised by just a few examples of increasing complexity: controllers in washing machines, air traffic control systems, control and safety systems of nuclear power plants and, finally, future military systems like the Strategic Defense Initiative (SDI). The import ance of such systems for the well-being of people requires considerable efforts in research and development of highly reliable real-time systems. Furthermore, the competitiveness and prosperity of entire nations now depend on the early app lication and efficient utilisation of computer integrated manufacturing systems (CIM), of which real-time systems are an essential and decisive part. Owing to its key significance in computerised defence systems, real-time computing has also a special importance for the Alliance. The early research and development activities in this field in the 1960s and 1970s aimed towards improving the then unsatisfactory software situation. Thus, the first high-level real-time languages were defined and developed: RTL/2, Coral 66, Procol, LTR, and PEARL. In close connection with these language develop ments and with the utilisation of special purpose process control peripherals, the research on real-time operating systems advanced considerably.







UNIX Review


Book Description




Automotive Simulation ’91


Book Description

Welcome to Bavaria - Germany - to the THIRD EUROPEAN CARS/TRUCKS SIMULATION SYMPOSIUM. That Schliersee traditional workshop-type meeting is a follow-up to the first and the second symposia which took place in May 1984 and May 1989 respectively. The objective of gathering together is to cover most of the aspects of Automotive Mathematical Modelling and Simulation in theory and practice to promote the exchange of knowledge and experience between different national and international research groups in that field, taking into consideration that every seventh German employee is related to the automotive industry. This effect is also in power at least with the traditional Detroit (U.S.A.) Automotive Industries and the growing up Japanease as well. Futhermore, there is to strenghten the international contact between developers and users of modelling and simulation techniques considering the "new world order" started in 1991 with no borders between West and East affected by the Golf-War and followed up by the "open" European Community borders of 1992. VI The traditional International Conference jointly promoted by ASIMUTH - Applied Simulation Technology and some other members of the Society of Computer Simulaton created an interest to publish new projects including their results. A large number of contributed papers has been strictly examined and selected by the editorial commitee to guarantee a high international technical standard.




Imprecise and Approximate Computation


Book Description

Real-time systems are now used in a wide variety of applications. Conventionally, they were configured at design to perform a given set of tasks and could not readily adapt to dynamic situations. The concept of imprecise and approximate computation has emerged as a promising approach to providing scheduling flexibility and enhanced dependability in dynamic real-time systems. The concept can be utilized in a wide variety of applications, including signal processing, machine vision, databases, networking, etc. For those who wish to build dynamic real-time systems which must deal safely with resource unavailability while continuing to operate, leading to situations where computations may not be carried through to completion, the techniques of imprecise and approximate computation facilitate the generation of partial results that may enable the system to operate safely and avert catastrophe. Audience: Of special interest to researchers. May be used as a supplementary text in courses on real-time systems.