Interactive networking

The Primenet software supports communication via local ring networks, point-to-point synchronous networks, and X.25 packet-switched networks. The paper outlines use of the networking software and its software modules — the interprogram communication facility, interactive terminal support facility and the file access manager. The manufacturer's own data-communications network, which links its installations in the USA, Canada and the UK, is described.     

Voice/data integration on Ethernet — backoff and priority considerations

Astudy of the CSMA/CD protocol as given in the Ethernet specifications, for real time (voice in particular) and mixed voice/data environments is described. The objectives of the study were to predict the Ethernet's behaviour under the current protocols, to point out potential improvements within the realm of the current specifications, and to improve understanding of the network behaviour in these environments. Results are given in terms of relative performance of the various system measures given as a function of system and traffic models. It is shown that the support provided to real time voice on Ethernet strongly depends on the assumptions made with regard to the coexisting data user's traffic and that with certain data traffic patterns the observed voice delay is much worse than previously reported. Finally, it is shown that without violating the Ethernet network specification, voice service can be improved by simple adjustments of the Ethernet retransmission ‘backoff’ algorithm.     

Using Knowledge-Based Neural Networks to Improve Algorithms: Refining the Chou–Fasman Algorithm for Protein Folding

This article describes a connectionist method for refining algorithms represented as generalized finite-state automata. The method translates the rule-like knowledge in an automaton into a corresponding artificial neural network, and then refines the reformulated automaton by applying backpropagation to a set of examples. This technique for translating an automaton into a network extends the KBANN algorithm, a system that translates a set of prepositional rules into a corresponding neural network. The extended system, FSKBANN, allows one to refine the large class of algorithms that can be represented as state-based processes. As a test, FSKBANN is used to improve the Chou–Fasman algorithm, a method for predicting how globular proteins fold. Empirical evidence shows that the multistrategy approach of FSKBANN leads to a statistically-significantly, more accurate solution than both the original Chou–Fasman algorithm and a neural network trained using the standard approach. Extensive statistics report the types of errors made by the Chou–Fasman algorithm, the standard neural network, and the FSKBANN network.     

Mathematical software libraries for vector computers

The principles of vector computation are reviewed including a definition of “depth of parallelism”. The latter concept is related to algorithm performance on various computer architectures (in particular the CRAY-1 and the FPS AP120B). The challenge of providing efficient mathematical software libraries on vector computers and the subsequent trade-offs introduced by vector architecture are discussed. Boeng's multi-level library approach to meet vector computer user's needs is explained. Some timing comparisons for software on the CRAY-1 are also given.     

Mapping external views to a common data model

In the context of a multilevel database management system architecture, the problem arises of translating, or mapping, operations at the user's representation level (the External Schema) into operations at the system's common logical level (the Conceptual Schema).In order to support different structured user's data models, the need for an unstructured, view-independent and yet carefully defined data model at the Conceptual Schema level is recognized.In this paper a binary model for the Conceptual Schema is illustrated through the specification of a set of primitives, and the elements of a language for the definition of a binary Schema and of the corresponding operations are given.Procedures are then illustrated for translating external into conceptual operations through exploitation of the primitives of the binary model. Two types of mapping specifications are illustrated: the operational mapping, in which the translation is explicitly defined, and the structural mapping, in which only the structural correspondences between elements of the External and the Conceptual Schema are defined. The automatic mapping between n-ary relational views and the binary Conceptual Schema is finally discussed.     

基于有限自动机的网络入侵容忍系统研究

网络环境下的入侵容忍系统，在面对攻击的情况下．入侵容忍系统仍然能连续地为预期的用户提供相应的服务．该文描绘了入侵容忍系统的有限自动机，该自动机模拟了入侵容忍系统的各个状态之间的相互转换的条件和工作过程．为入侵容忍系统的行为描述和结构设计提供了理论依据，最后在此基础上讨论了一个入侵容忍实例．     

Handsketching as a human factor aspect in graphical interaction

For some years a lot of effort has been put into improving the human-computer interface in CAD-systems. After a short introduction on input problems in design processes, some of this work is reported here as well as a fairly new method, handsketching. In the third part of this paper a special system called CASUS is thoroughly explained from the user's point of view. A fourth part deals with the authors' conviction that psychological theories and methods are necessary in order to create still better interfaces. In the last chapter the system presented with all its interface features is compared to some human factor considerations discussed before. No attention is paid to the fact that very often the quality of work is changed by introducing CAD-systems. Though the designer's situation can be very often improved much more by designing his entire work, this paper lays claim only to designing a tool for the designer's hand.     

Buddy tracking — efficient proximity detection among mobile friends

Global positioning systems (GPS) and mobile phone networks make it possible to track individual users with an increasing accuracy. It is natural to ask whether this information can be used to maintain social networks. In such a network each user wishes to be informed whenever one of a list of other users, called the user’s friends, appears in the user’s vicinity. In contrast to more traditional positioning based algorithms, the computation here depends not only on the user’s own position on a static map, but also on the dynamic position of the user’s friends. Hence it requires both communication and computation resources. The computation can be carried out either between the individual users in a peer-to-peer fashion or by centralized servers where computation and data can be collected at one central location. In the peer-to-peer model, a novel algorithm for minimizing the number of location update messages between pairs of friends is presented. We also present an efficient algorithm for the centralized model, based on region hierarchy and quadtrees. The paper provides an analysis of the two algorithms, compares them with a naive approach, and evaluates them on user motions generated by the IBM City Simulator system.     

Standardizing the user side of the X.25 interface

CCITT Recommendation X.25 describes the interface to a public data network operating in the packet mode. However, it describes this interface almost entirely from the network's viewpoint. Investigations within ANSI X3S3 in 1980 showed that X.25 leaves open many issues regarding DTE operation. As a result, ISO/TC97/SC6, at ANSI's request, undertook an activity to define DTE operation for both DTE-to-DCE (network) operation as well as direct DTE-to-DTE operation. In June 1981, ISO/TC97/SC6 approved for balloting among its member countries a draft proposal of an X.25 LAPB-compatible DTE link layer standard. The results of this balloting were favourable; the DP was then forwarded to ISO/TC97 for further processing as a draft international standard. A proposed X.25 DTE packet layer standard has been submitted to ISO for further consideration within TC97/SC6. The purpose of this paper is to briefly trace the history of this activity and to provide insight into the proposed ISO DTE standards.     

A fact dependency system for the logic programmer

We describe experimental work in logic programming for architects, leading to the setting up of a fact dependency system. The system operates as an interpreter of the user's instructions, storing his decision and the conclusions inferred from those decisions. Consistency from a user's point of view is automatically maintained. A separate introduction to the Prolog logic programming language is appended to this paper.     

Developing a software system for automata-based code generation

This paper is devoted to the development of the State Machine Generator system meant for automatic code generation based on the principles of automata-based programming. This system models program logic in terms of the finite-state automaton transition graph and generates program code on its basis. Basic functions of the developed software system and the mechanism of their implementation are described. This paper also proposes a new pattern for designing automaton programs. As an example, State Machine Generator is used to develop a bug tracker system for software testing.     

Alternatives to SNA

The advantages of changing from a network configured with IBM's preSNA equipment (hosts, host software, communications processors, terminals) to one using SNA are reviewed. Two viable alternatives to SNA are considered. One relies on data comunications architectures as developed by two vendors (NCR-Comten, CCl) of plug-compatible replacements for IBM's 3704/3705 communications controllers. Packet-switched public data networks provide a second alternative. Host software remains unchanged in both instances.     

Intelligent System for Adapting to a User’s Characteristics

In this paper, we propose an intelligent system that adapts itself to a user’s characteristics or habits. The proposed intelligent system is composed of two Learning Vector Quantisation (LVQ) networks, commonly used in the fields of pattern recognition and signal processing. From the external condition of the plant, the first LVQ network learns to recognise the pattern of the sensed signal, and then aids the second LVQ to learn the user’s characteristics or habits so as to automatically produce the user’s favoured output. To verify the usefulness of the proposed method, we simulated and experimented with a variable illuminator. Both simulation and experimental results showed that the proposed intelligent system learns to automatically produce the illuminator output that the user most favours for the circumstances.     

Analysis and design for a standard transport protocol

In the development of computer networks, the trend towards open systems interconnection is creating the need for standard protocols. The transport level protocols published by ECMA and ISO are supported by the Department of Industry as ‘intercept’ standards to be adopted by the computing community as a whole. This paper presents the published standards interpreted as a set of state transition diagrams. This reinterpretation is a necessary prerequisite to the method of implementation which is based on a finite state automaton. We summarize the advantages of a software ‘funnel machine’ to effect the state transitions during the execution of the transport protocol server. The same analysis and design technique has been used successfully to implement network and link protocol handlers. We recommend its adoption on a variety of machines in any programming language to ensure a relatively short development period and to achieve compatability among the different classes: 0, 1, 2, 3 and 4, of the transport protocol.     

An Approximate Determinization Algorithm for Weighted Finite-State Automata

Nondeterministic weighted finite-state automata are a key abstraction in automatic speech recognition systems. The efficiency of automatic speech recognition depends directly on the sizes of these automata and the degree of nondeterminism present, so recent research has studied ways to determinize and minimize them, using analogues of classical automata determinization and minimization. Although, as we describe here, determinization can in the worst case cause poly-exponential blowup in the number of states of a weighted finite-state automaton, in practice it is remarkably successful. In extensive experiments in automatic speech recognition systems, deterministic weighted finite-state automata tend to be smaller than the corresponding nondeterministic inputs. Our observations show that these size reductions depend critically on the interplay between weights and topology in nondeterministic weighted finite-state automata. We exploit these observations to design a new approximate determinization algorithm, which produces a deterministic weighted finite-state automaton that preserves the strings of a weighted language but not necessarily their weights. We apply our algorithm to two different types of weighted finite-state automata that occur in automatic speech recognition systems and in each case provide extensive experimental results showing that, compared with current techniques, we achieve significant size reductions without affecting performance. In particular, for a standard test bed, we can reduce automatic speech recognition memory requirements by 25—35\percent with negligible effects on recognition time and accuracy. Received March 31, 1998; revised January 29, 1999.     

Context-prediction performance by a dynamic Bayesian network: Emphasis on location prediction in ubiquitous decision support environment

Ubiquitous decision support systems require more intelligent mechanism in which more timely and accurate decision support is available. However, conventional context-aware systems, which have been popular in the ubiquitous decision support systems field, cannot provide such agile and proactive decision support. To fill this research void, this paper proposes a new concept of context prediction mechanism by which the ubiquitous decision support devices are able to predict users’ future contexts in advance, and provide more timely and proactive decision support that users would be satisfied much more. Especially, location prediction is useful because ubiquitous decision support systems could dynamically adapt their decision support contents for a user based on a user’s future location. In this sense, as an alternative for the inference engine mechanism to be used in the ubiquitous decision support systems capable of context-prediction, we propose an inductive approach to recognizing a user’s location by learning a dynamic Bayesian network model. The dynamic Bayesian network model has been evaluated with a set of contextual data from undergraduate students. The evaluation result suggests that a dynamic Bayesian network model offers significant predictive power in the location prediction. Besides, we found that the dynamic Bayesian network model has a great potential for the future types of ubiquitous decision support systems.     

Intelligent automatic community grouping system by multiagents

We have developed an intelligent ubiquitous web-based e-learning system based on multiagents. The proposed system, intelligent ubiquitous web-based e-learning multiagent system, uses the new distributed multiagent framework and neural networks for e-learning grouping. The proposed system implements the user’s individual satisfaction network by analyzing the degree of satisfaction among learners in groups in a web environment. The satisfaction network is personalized by providing weights to the learners’ degree of satisfaction in the e-learning grouping. It constructs the learners’ satisfaction network model about the e-learning grouping. Based on this network model, the proposed system can decide if the group remains, or is reorganized, or breaks down for the next time, and the system learns about these states. This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27, 2007     

一种基于时间自动机的时钟等价性优化方法

提出了一种优化模型检验时间自动机的时钟等价规则,通过优化的时钟等价规则,使时间自动机等价后的域自动机状态数尽可能少,并在此基础上定义了适合于优化时钟等价规则的域自动机.优化时钟等价规则,在一定程度上有效地解决了状态空间爆炸问题.