A two phase procedure for the study of computer network reliability in automated manufacturing systems

This paper presents a simple procedure for the study of unreliable networks in production systems. An automated manufacturing system requires a network support for its stations in specific topological forms. However, the analysis presented in this study is topology independent. It reveals that, in most cases, the incremental cost due to failure of any component in the network will justify addition of standby units. The manufacturing facilities are assumed to be failure free and therefore, excluded from the analysis. A case study is presented to illustrate the importance of reliability analysis during the design phase.     

The structure of the Japanese fifth generation computer project — then and now

The FGCS programme has shown since its inception a gradual development through several stages of planning     

Interactive computer graphics for the generation of phase plane portraits

This paper describes the use of computer graphics facilities for generating phase plane portraits by truly interactive means. The final portrait produced is completely governed by the user who chooses the starting points for any particular future trajectories using only the graphical information currently available to him on the screen.     

A dual‐feed MIMO antenna pair with one shared radiator and two isolated ports for fifth generation mobile communication band

In this article, a pair of unsymmetrical dual‐feed antennas with one shared radiator and two isolated ports is proposed for multiple‐input‐multiple‐output (MIMO) systems. The proposed antenna pair achieves high isolation between the two ports by properly adjusting the distance between the two feeding ports and the position and length of shorting strips on the radiator. The antenna has simple structure and covers the 3.3‐3.7 GHz band, which could meet the demand of future 5G applications. The measured results show that antenna has good impedance matching (better than 10 dB return loss) and high port isolation (better than 20 dB isolation) from 3.35 to 3.65 GHz. The total efficiencies are above 55% and the envelope correlation coefficient is <0.1, which is sufficient for MIMO applications.     

A formalization for the specification and systematic generation of computer graphics systems

A formalization of graphical processes in computer graphics systems is presented in terms of functions and their system of axioms. The concept of the viewing pipeline is formalized as operation sequence which is a sequential composition of graphical elementary operations. The formalization includes two kinds of operation sequences which are used as the formal specifications of graphics systems and display devices. In order to generate a graphics system using a display device, we introduced the concept of functionality-preserving transformation of operation sequences in terms of various types of commutations among primitive operations. A type of transformation, which is called extraction, plays a central role in the generation algorithm.     

Automatic generation of parallel programs for mimd computer systems

Conclusion The use of linear-time automatic algorithms for sequential program parallelization substantially expands the scope of MCS. Parallel implementation is justified from time considerations even when the application program is executed only a few times without modification (only once when the macrooperation system is introduced), i.e., for frequently reprogrammed jobs. Only linear-time parallel-branch algorithms ensure that the execution frequency of the application program that justifies parallel implementation is independent of the number of statements in the program and allow the size (computational complexity) of the macrooperations treated as parallelization units to be varied between wide limits both in the direction of greater aggregation and in the direction of refinement. At the same time, the linear-time parallel-program generation algorithms proposed in this paper produce programs of acceptable quality. Translated from Kibernetika i Sistemnyi Analiz, No. 5, pp. 170–179, September–October, 1995.     

Lattice QCD results from the CP-PACS computer

We present physics results from large-scale simulations of Quantum Chromodynamics (QCD) on the space-time lattice carried out with the CP-PACS computer. The CP-PACS is a massively parallel system with a peak speed of 614 Gflops and 320 Gbyte of main memory developed at the Center for Computational Physics, University of Tsukuba.Since the start of full operation of CP-PACS in October 1996, precision calculation of the light hadron spectrum in the quenched approximation of QCD and a systematic attempt at a calculation without this approximation have been pursued. Physics motivations of these calculations, the computational difficulties,and advances brought in by the CP-PACS are discussed. Performance of the CP-PACS for lattice QCD computations are described in a companion paper by S. Aoki et al.     

第五代移动通信系统的研究分析

较详尽地叙述了第五代移动通信(5G)应具有的基本特点,分析了对其需求以及发展线路,对5G网络架构进行研究,并根据移动通信技术的发展规律研究了其可能用到的关键技术;最后提出提高5G无线网络容量的研究方向以及采用到的关键技术。     

MRF: A FORTRAN IV computer program for the generation of univariant phase equilibria

A computer program, MRF, has been designed to generate all possible equations for chemical reactions between a chosen set of phases. All subsets of the phases are chosen and arranged into an equation and balanced using the formula Ax = b. A is a m × n matrix of rank n composed of n compositional vectors, b is a m dimensional vector and x is a (n + 1) dimensional vector of reaction coefficients. A m × n matrix also allows the solution to be independent of the components chosen. Provision is made for the exclusion of up to 5-phase assemblages.     

Safety of computer control systems: challenges and results in software development

This paper reviews some results in improving software safety in computer control systems. The discussion covers various aspects of the software development process, as opposed to the product features. Software diversity, off-the-shelf software, failure mode and effect analysis, rigorous and formal software development are discussed.     

On the computer generation of the Erlang and negative binomial distributions with shape parameter equal to two

We provide closed-form expressions for the quantile functions of the Erlang and negative binomial distributions with shape parameter equal to two. These expressions are related to the Lambert W function.     

Probabilistic models of computer systems—Part I (exact results)

Summary This paper is a survey of certain known results concerning networks of queues. The choice of the topics presented has been made with special emphasis on mathematical results which can be applied to the analysis and synthesis of mathematical or simulation models of complex computer systems in which an ensemble of resources is shared among a set of user programs. The subjects covered include the Jackson, and Gordon and Newell theorems; the work-rate theorems of Chang, Lavenberg and Traiger; the Baskett, Chandy, Muntz, Palacios results. We also discuss in a unified manner problems related to Poisson processes in queueing networks. Companion papers (Parts II, III) will present results concerning approximations to queueing networks and some of their applications to computer system performance evaluation.     

Continuous sliding-mode control for underactuated systems: Relative degree one and two

This paper deals with the design of sliding-mode controllers for the stabilization of some types of underactuated systems. The proposed method takes advantage of the mechanical properties of three different types of underactuated systems instead of using nonlinear transformations. In order to design the controller, some sliding variables with relative degree one and two are introduced. The theoretical differences between these approaches are discussed and some simulation results show the practical differences. Experimental results on a cart–pole system are presented to validate the proposed control strategy.     

Standards-ethics and the safety of computer systems

The issue of responsibility for computer failures in critical systems is addressed, taking medical information systems as an example. Three basic modes of ethical analysis are defined and used to analyze the ethical questions raised for such systems. The first, called normative ethics, seeks to develop and justify rules for right conduct. The second, called the ethics of virtue, asks what kind of person does the right thing; thus, it concerns questions of character. The third mode, called social ethics, recognizes that values and choices are not only expressed in individual actions, but are embodied effectively in social structures, and asks what structures are needed to support values such as justice and respect for human life and dignity