Juricas: Legal computer advice systems

In the late seventies at the Centre for Computers and Law research was started to find means for supporting lawyers' work with the aid of a computer. The research project was called JURICAS. In 1982 a prototype of a JURICAS system was produced and since 1986 seven advisory packages have been brought out on the market in the Netherlands. These packages consist of two main parts, an author's shell and an advisory program. The user cannot make changes to either the shell or the program.In 1988 the JURICAS author's shell became commercially available. A buyer has to make his own advisory program and fill it with his expertise to produce an advisory package. To facilitate the designing, the typing in and the testing of a package a number of utility programs are included in the author's system.An example of a self-developed legal computer advice system is a JURICAS system for Social Security Law. This system was written by two lawyers of a social security service in the Netherlands and helps with the processing of requests for social security. In May 1991 the computer advice system was put into use.     

A family history of Honeywell's large-scale computer systems

Honeywell Information Systems marketed a broad line of large computer hardware and software, whose heritage goes back to the early 1960s. The authors of this article played key roles in the evolution of today's software (King) and hardware (Shelly)     

People's perception of human and computer advice

The aim of the present paper is to study users' perception of computers and human beings as advice givers in problem-solving situations. It will be asked if people's self-confidence and their perception of the advice vary depending on the origin of advice.Two studies showed somewhat different results. In the first study, people were given advice either by a (putative) computer or by a human being. Their self-confidence did not vary with the origin of the advice, but with the correctness of their own answer as well as of the advice. The perception of this advice did not differ for the two situations. Their general trust in computers was, however, much less than their trust in human beings. In the second study, the subjects had to attribute advice to a computer or a human being, without being told from whom the advice emanated. For Swedish subjects, the ratings showed consistently higher attributions to human beings regarding knowledge and explanation value of advice and higher attributions to computers regarding trust and understanding. For Indian subjects, humans always received the higher attributions.It was concluded that people's perception of computers seems to be related both to existing attitudes and to their experience of the advice given. Knowledge in the domain seems to be an important factor influencing the perception of the computer as trustworthy.     

Constructing a family of algorithmic languages for programming and design of multiprocessor computer systems

Conclusion The paper describes approaches to building a family of compatible algorithmic languages for design of circuitry and programming software for multiprocessor systems under development at the Institute of Cybercsics of the Academy of Sciences of the Ukrainian SSR. Several members of the family are completed. These ALGORITHM-80 language oriented fro combined design of hardware and programs, multimodule programming language MMP, belonging to the parallel algorithmic level, and arithmetic macroconveyor language AMC, belonging to the problem functional level and oriented to computational mathematics. The latter two languanges are to be used for recursive computer programming [17].Translated from Kibernetika, No. 1, pp. 1–7, January–February, 1981.     

A tridiagonal solver for massively parallel computer systems

This paper describes a parallel solver of tridiagonal systems appropriate for distributed memory computers and implemented on an array of chain-connected T800 Transputers. Each processor in the chain uses the same program to solve its own subset of equations. This implementation is suited, for instance, for solving the heat conduction equation in one-dimensional hydrodynamic codes. The procedure performs a parallel cyclic reduction, a recursive Gaussian elimination on a reduced number of equations and a parallel backward unfolding scheme, with a direct substitution in the reduced equations. The code has been written in Occam2 language. A one-way communication of values between adjacent processors is required at each cycle of both the reduction and the unfolding steps. Due to the number of floating point operations and the amount of communications the implementation described here works efficiently on arrays with more than 4 processors and for more than 50 equations per processor.     

A software architecture for distributed computer control systems

Distributed computer control systems have a number of potential advantages over centralized systems, especially where the application is itself physically distributed. A computer station can be placed close to the plant being controlled, and a communications network used to enable the stations to communicate to coordinate their actions. However, the software must be carefully designed to exploit the potential advantages of distribution. This paper describes the software architecture of CONIC, a system to support distributed computer control applications. This architecture emphasizes the distinction between the writing of individual software components and the construction and configuration of a system from a set of components. A modular structure is used to separate programming from configuration. Typed entry and exit ports are used to clearly define module interfaces. Ports, analagous to the plugs and sockets of hardware components, permit modules to be interconnected in different ways. On-line modification and extension of the system is supported by permitting the dynamic creation and interconnection of modules. Message passing primitives are provided to permit modules to coordinate and synchronize control actions.     

A mathematical model for transient analysis of computer systems

The study of computer system dynamic behavior is a prerequisite for the design and implementation of automatic mechanisms for performance control. An analytic technique for modelling the transient behavior of computer systems is presented and a suitable method for modelling job dynamics is given.

The system model is discussed from the viewpoint of transient analysis with particular reference to bottleneck identification and to bottleneck migration analysis.

A mathematical study is given together with a numerical algorithm. The model is validated on the basis of suitable experimental results.     

Proof systems that take advice

One of the starting points of propositional proof complexity is the seminal paper by Cook and Reckhow [J. Symbolic Logic, 1979], where they defined propositional proof systems as poly-time computable functions which have all propositional tautologies as their range. Motivated by provability consequences in bounded arithmetic, Cook and Kraj?´?ek [J. Symbolic Logic, 2007] have recently started the investigation of proof systems which are computed by poly-time functions using advice.In this paper we concentrate on three fundamental questions regarding this new model. First, we investigate whether a given language L admits a polynomially bounded proof system with advice. Depending on the complexity of the underlying language L and the amount and type of the advice used by the proof system, we obtain different characterizations for this problem. In particular, we show that this question is tightly linked with the question whether L has small nondeterministic instance complexity.The second question concerns the existence of optimal proof systems with advice. For propositional proof systems, Cook and Kraj?´?ek gave a surprising positive answer which we extend to all languages.These results show that providing proof systems with advice yields a more powerful model, but this model is also less directly applicable in practice. Our third question therefore asks whether the usage of advice in propositional proof systems can be simplified or even eliminated. While in principle, the advice can be very complex, we show that propositional proof systems with logarithmic advice are also computable in poly-time with access to a sparse NP-oracle. Employing a recent technique of Buhrman and Hitchcock [CCC, 2008] we also manage to transfer the advice from the proof to the proven formula, which leads to a more practical computational model.     

A radio network for monitoring and diagnosing computer systems

By offering improved reliability and lower implementation cost, an interconnect technology based on radio communication provides an attractive alternative for implementing system functions requiring out-of-band signaling.     

A feedback-coupled resource allocation policy for multiprogrammed computer systems

Summary An earlier paper on an adaptive workload balancing strategy to achieve efficient resource utilization is extended to include memory cost. The scheme corrects for the imbalance in resource utilization by bringing into play the “Invisible Hand” of classical economics. In this framework, the memory price and the bid, W _ij, of each user program U _jfor resource R _iare calculated adaptively. These prices are not apparent to the users, but they are rather shadow prices determined from the characteristics of user programs, the current resource congestion, and the budget constraints of users. There emerge a set of effective priorities for user programs based on the bid prices, W _ij, and these determine the scheduling of programs. An imbalance due to high congestion of some resource will result in a relative decrease of priority for heavy users ofthat resource and a relative increase for light users. Some ideas on an actual implementation scheme are described based on an approximation to the above abstract scheme. It is shown that this approximate scheme will also tend to balance resource utilization.     

A survey of digital computer memory systems

Many types of storage and memory systems have been proposed for use in digital computing systems. The survey paper discusses only the various systems whose reaction time is faster than human reaction time and employs a historical approach to the subject. Criteria for evaluation are discussed as well as comparisons among the different systems as to general applicability, ease of construction and use, speed of operation, latency time, memory span, and economy     

A scheme for the realization of graphical computer aided design systems

We present some of the problems encountered in the study of CAD systems in an electro-mechanical company, and propose a methodology based entirely on a detailed object study. In the first part of this paper we analyse the traditional design process in the company and define the most important functions of a CAD system. In the second part, we show how a functional hierarchical decomposition of the product helps us to realize the CAD system, and then we describe the practical application.     

Development methods for trusted computer systems

Conclusion Well-designed computer systems can be safer than hardwired alternatives, and computer systems can control processes which are too complex for hardwired solutions, or where the hardwired solution is uneconomic.     

Diffusion approximation for multiprogrammed computer systems

This paper presents results of diffusion approximations which may be used in the analysis of multiprogrammed computer systems. First of all we give a mathematical proof for the best CPU utilization under different priority rules in the case of one CPU and more DTU-s. With the help of the Brownian motion approximation we get an explicit result for a model considered by Gaver and Shedler in priority queues, without using the Wald identity. Some examples are given when the diffusion approximation is more complicated than the Brownian motion one.     

Performability analysis for degradable computer systems

Degradable performance of fault-tolerant computer systems has given rise to considerable interest in mathematical models for combined evaluation of performance and reliability. Most of these models are based upon Markov processes. Several methods have been proposed for the computation of the probability distribution of performability upon an interval of time [0, t]. In this paper, we present a new algorithm based on the uniformization technique to compute this distribution for block degradable models. The main advantage of this method is its low polynomial computational complexity and its numerical stability, since it only deals with a nonincreasing sequence of positive numbers bounded by 1. This important property allows us to determine new truncation steps which improve the execution time of the algorithm. We apply this method to a degradable computer system.     

A family of standards for software and systems product lines

There is a drastic rise and evolution of Software and Systems Product Lines (SSPL) as a potential solution to deliver quality software products in a shorter time and with less effort. This has led to a plethora of diversified tools across the entire life cycle of SSPL, making it difficult for product line organizations to select the right set of tools for product line realization and tool vendors to develop interoperable tools. In this paper, we motivate the need for standardization of tools and methods for SSPL. The ISO/IEC JTC1/SC7 (Software and Systems Engineering) of the International Organization for Standardization (ISO) has proposed a set of interrelated standards in the area of SSPL to cater to the emerging demands of software and systems industry. We present the foundation of SSPL family of standards that are driven by market needs and discuss the core patterns and processes of SSPL. We then present an overview of ISO/IEC 26550, which is the reference model for SSPL family of standards and provide examples from current and ongoing standards. We highlight a few examples of industry adoption of SSPL and standards and emphasize the need for further research for standards in SSPL. We see this paper as a first step to bring standards knowledge into the academic world in the field of SSPL.