永久对象存储技术研究

永久对象存储技术为程序员提供了在高级语言一级操纵内，外存的能力，永久对象存储技术的研究体现在永久性面向对象程序设计语言，面向对象数据库和对象管理系统的实践中，本文讨论了永久对象存储的相关概念及基本要求，概述了ＰＯＯＰＬ，ＯＯＤＢ和ＯＭＳ的有关内容，之后介绍了ＪＢ２／ＯＭＳ的设计，并简要讨论了一个分布式对象存储的原型设计。     

基于CORBA的永久对象技术研究

本文在结合对象管理组制定的永久对象服务标准，利用框架技术讨论了基于CORBA的永久对象服务、存储以及面向对象数据库中永久性机制的设计，最后对COBRA与00DB的集成进行了探讨。     

Implementing OSI systems

The correct and efficient implementation of complete open systems interconnection systems comprising the specified multiple layers of complex protocols is discussed. Also examined are the specification, design, and implementation issues and approaches at two levels: the realization of the individual protocols; and the construction of complete multilayer communication systems. The design of a multilayer communication subsystem which can run on the same processor as the applications or be confined to a front-end processor is discussed     

Optical Transmission Fiber Design Evolution

This paper reviews optical fiber design evolution for transmission systems over the past three decades, including both multimode and single-modes fibers. Key fiber attributes related to fiber transmission systems and how fiber designs have evolved to improve these attributes to enable higher and higher transmission data rate are discussed. Major fiber design change milestones in the past are covered. Also discussed are recent new developments in optical fiber technology.     

多进制数字调相系统分析与设计方法的探讨

对数字通信中MPSK系统的调制与解调问题进行了较为的分析，并以8PSK和循环码16PSK系统为例，阐述其调制器电路的逻辑设计方法。在此基础上给出了8PSK系统调制与解调的一种方案，讨论了循环码和自然二进制码16PSK系统的调制器的具体设计过程，该设计方法可应用于一般MPSK系统的逻辑设计。     

Speaker recognition: a tutorial

A tutorial on the design and development of automatic speaker-recognition systems is presented. Automatic speaker recognition is the use of a machine to recognize a person from a spoken phrase. These systems can operate in two modes: to identify a particular person or to verify a person's claimed identity. Speech processing and the basic components of automatic speaker-recognition systems are shown and design tradeoffs are discussed. Then, a new automatic speaker-recognition system is given. This recognizer performs with 98.9% correct decalcification. Last, the performances of various systems are compared     

Designing with fuzzy logic

Fuzzy logic is examined, and its application to control systems is discussed. The steps taken to design a fuzzy controller are described, and the possibility of interfacing fuzzy logic to existing control systems is noted. Tools for developing and modeling fuzzy control systems are described     

A survey of systems approaches to green design with illustrationsfrom the computer industry

Increased recognition of the importance of sustainable development is posing new challenges for industry. A systems approach provides a framework for reconciling the needs of sustainable development with all of the other demands on industry. The computer industry has been chosen to illustrate the application of a systems approach to green design in industry on account of both its increasing economic importance and the increasing role of computers in society. A brief discussion of the current environmental impact of the computer lifecycle is presented to set the context for the discussion of systems approaches to green design, and a survey of existing systems-based design approaches and discussion of their application to the computer industry is given. A number of examples are presented to illustrate the advantages and application of a systems approach to green design, and the principles as well as some of the main issues in a systems approach to green design in the computer industry are discussed     

柔性通信指挥管理信息系统总体设计

多样化军事任务的复杂性和多变性,迫切需要多样化的通信保障。从多样化军事任务对通信保障的需求出发,分析了通信指挥管理信息系统的结构柔性、运行柔性和数据柔性的需求,对通信指挥管理信息系统的总体构成、功能组成和总体技术体系结构进行了初步研究,说明了系统结构柔性、运行柔性及数据柔性的实现。     

A tutorial on protocols

Protocols are common tools for controlling information transfer between computer systems. The concept of a protocol, which grew out of experimental computer networking, is now fundamental to syatem design. In this paper, basic protocol functions are explained and discussed. Then, the concept of a distributed system architecture is presented. It provides the framework for layers and protocols to operate across heterotgeneous systems. The purpose and functions of each protocol layer such as, transmission, transport, virtual terminal, are described. Interactions between design and performance are discussed, and typical mechanisms are reviewed. CCITT and ISO relevant standards are summarized. Finally, the similarity between protocols and programming languages is emphasized as it points to the major impact brought about by protocols in system design.     

Optical fiber submarine cable systems

Optical fiber submarine cable systems especially developed for international systems throughout the world are reviewed, and the future technologies for optical fiber submarine cable systems are discussed. The discussion covers: system design; cable design and the fiber used; mechanical design of submarine optical repeaters; branching repeaters; repeater circuits; reliability; terminal equipment; repeater supervisory systems; initial system applications; and future trends     

A user-centered approach to define high-level requirements fornext-generation CAD systems for mechanical engineering

The authors describe work undertaken within the Alvey Research Programme in the United Kingdom. They outline some of the user problems that have been discovered with CAD (computer-aided design) systems. These are then discussed in relation to the design process and, on the basis of studies of users, a less-structured, more opportunistic version of the mechanical engineering design process is described. The implications of this for the design of the CAD systems of the future, the intelligent systems are stated as global requirements, and a conceptual model based on a blackboard architecture is outlined which incorporates the requirements and allows articulation of their consequences. Finally, some as yet unanswered research questions are given     

WDM-based local lightwave networks. I. Single-hop systems

An overview of emerging all-optical networks is given. The characteristics and alternative architectures for single-hop systems are discussed. The characteristics of lightwave technology that facilitate the design of wavelength-division-multiplexing (WDM) networks are reviewed, and it is explained how WDM local networks can be built based on the single-hop and multihop approaches. Various categories of single-hop systems are discussed: experimental systems, systems based on no pretransmission coordination, and systems based on pretransmission coordination, which also require a separate control channel. A simple classification for single-hop systems is provided     

The design of large-scale networks

The application of computer techniques to difficult large-scale network problems is discussed. The physical characteristics of two types of systems are described--computer-communication networks and cable television distribution systems. Two fundamental algorithms are presented, and applications to routing, reliability, and design of computer networks are given. The detailed engineering decisions that can be made by computer in the design of practical large-scale networks are illustrated by example for cable television systems. These examples are chosen to indicate the richness and difficulty of the problem of applying computers to network design.     

A case study of C.mmp, Cm*, and C.vmp: Part I—Experiences with fault tolerance in multiprocessor systems

Three multiprocessor systems designed, implemented, and currently operational at Carnegie-Mellon University are compared and contrasted. The design goals and architectures are summarized with a special focus on reliability features. Experiences gained in design and operation are discussed. Finally, reliability data, with a focus on transient failures, measured from each system are presented and discussed.     

Design concept of antennas for small mobile terminals and the future perspective

With the progress and rapid increase in mobile terminals, the design of antennas for small mobile terminals is acquiring great importance. In view of this situation, the design concept of antenna systems for small mobile terminals and its future perspective are discussed, referring to the trends in modern mobile communications and the demands for the antenna system. The design concept of antenna systems has changed along with the progress of mobile systems. In the conventional design, the conducting material of the equipment case, existing near the antenna element, is included as a part of the radiator in the antenna system, without regard to whether or not it has been considered. In the latest mobile phones, the design concept has been advanced to aim at improving the antenna's performance, and the treatment of the case, etc., has become a part of this. Some particular considerations for the design are to relieve the degradation of the antenna's performance due to the human-body effect, to overcome the SAR problems, and yet to make the size small. Furthermore, it is now time to proceed to the more-advanced concept, in which implementation of adaptive control and software is considered, even in small mobile terminals. Typical trends in modern communications systems are discussed, and the demands of these trends-which are summarized as down-sizing, function, and intelligence-are taken up for future antenna structures. Small-antenna technology and the application of the integration technology to antenna systems are essential for realizing such future structures.     

Computing with uncertainty

The role of and interaction between statistical, fuzzy, and neural-like models for certain problems associated with the three main areas of pattern recognition system design are discussed. Some questions concerning fuzzy sets are answered, and the design of fuzzy pattern recognition systems is reviewed. Pattern recognition, statistical pattern recognition and fuzzy pattern recognition systems are described. The use of computational neural-like networks in fuzzy pattern recognition is also discussed     

The emerging role of flexible media

The evolution of systems that use flexible magnetic media for data storage is reviewed. The exponential increases in performance of these systems has imposed continually changing requirements upon the media. Because of the great diversity in the market requirements for tape systems, developments are addressed by market segments, the corresponding advances in magnetic tape design and manufacture are examined. The design of tapes to simultaneously optimize electromagnetic, mechanical, and tribological performance, and the key design parameters for these properties, are discussed     

Managing VLSI complexity: An outlook

The nature of complexity in the context of VLSI circuits is examined, and similarities with the complexity problem in large software systems are discussed. Lessons learned in software engineering are reviewed, and the applicability to VLSI systems design is investigated. Additional difficulties arising in integrated circuits such as those resulting from their two-dimensionality and from the required interconnections are discussed. The positive aspects of VLSI complexity as a way to increase performance and reduce chip size are reviewed. With this discussion as a basis, the evolution of VLSI system design environments is outlined for the near-term, medium-term, and long-term future. The changing role of the designer is discussed. Recommendations are made for enhancements to our engineering curriculums which would provide the next generation of designers with skills relevant to managing VLSI complexity.