摘要:

AbstractAs a method of fast simulation of queueing networks by parallel processing there is D‐SSQ which uses the limited‐advance processing scheme. The processing capability of the limited‐advance processing scheme has been shown to increase linearly as the concurrency of the model increases. However, on the other hand, if the updating of the maximum logical time requires considerable time after which no processor backtracks (confirmed time), its performance is degraded considerably. Also, the optimal limit of advance must be estimated from the simulation model. In this paper, to improve on these shortcomings, a time‐event driven scheme is proposed. In this scheme the system clock is managed by a central processor and each processor performs the limited‐advance processing within a certain logical time (clock) of the system time. Second, an adaptive time‐event driven method is presented. In this scheme the optimal limit need not be estimated prior to execution and the global clock is changed dynamically to achieve the maximum performance. The processing capabilities of these two methods are measured by experiments and simulations on a

ISSN:0882-1666    

DOI:10.1002/scj.4690210101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractAs interactive computer systems become popular, the study of pointing devices is becoming more important. This article discusses research on the efficiency of pointing methods which include the combination of a pointing device and its controlling software. One observation from this research is that the pointing efficiency is worse on a model with a smaller target size. Here, we propose a new pointing method—the Brake Type Method—in order to reduce the error rate. In this method, we try to make pointing easier through sufficient control of the movement of the mouse‐cursor. This method was evaluated in an experiment, which was also done with a digitizer (a popular pointing device for graphics). Conclusions indicate that the Brake Type Method proposed here is quite effective in reducing the error rate without losing other aspects of pointing effic

ISSN:0882-1666    

DOI:10.1002/scj.4690210102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractThis paper describes a new statistical method of segmentation using a hidden Markov model (HMM) and a Bayes' classifier. The main characteristics of this method are the use of feature parameters which are independent of each category in vowels or consonants, and the use of only one HMM which represents all syllable patterns in common. The segmentation strategy is to find the optimal HMM sequence. The optimal/best sequence is found by using the O(n) DP matching based on the Viterbi algorithm. The concatenated number and boundaries of the best HMM sequence are regarded as the segmentation result.

ISSN:0882-1666    

DOI:10.1002/scj.4690210103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractA software environment for interactively synthesizing communication protocols without logical errors has been developed. It contains a synthesis algorithm which eliminates the logical errors, and a human interface which has a multiwindow environment, a graphical interface, colors and texts utilities. Moreover, it not only expresses the synthesized protocol as labeled directed graphs, but also provides advices on how to give the input for the protocol designer by using the colors and the texts utilities. Consequently, the protocol design has been facilitated. As an example, a call‐establish phase of X.25 has been synthesized by using the software environmen

ISSN:0882-1666    

DOI:10.1002/scj.4690210104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractFeature selection is one of the most important processes in the design of pattern classifiers. This paper presents an optimum feature selection method which is applicable to arbitrary (nonlinear) decision functions. It is assumed that a finite number of training samples (training set) is given for each pattern class, and the decision function is designed based on the training sets. The training sets are edited by removing the samples which are classified incorrectly by the decision function. Then the feature selection problem is transformed to a modified zero‐one integer program. In this method, under a chosen permissible error, a minimum feature subset can be found which is combinationally optimum. Numerical examples of feature selection for a linear and a quadratic decision function are presente

ISSN:0882-1666    

DOI:10.1002/scj.4690210105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractThis paper proposes identity‐based key distribution systems for generating a common secret conference key for two or more users. Users are connected in a ring, a complete graph, or a star network. Messages among them are authenticated using each user's identification information. The security of the proposed systems is based on the difficulty of both factoring large numbers and computing discrete logarithms over large finite field

ISSN:0882-1666    

DOI:10.1002/scj.4690210106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractAlthough the Hough transformation is a powerful method to detect segments in an image, it requires not only a vast amount of memory but also a long processing time when a highly accurate detection is demanded. This paper proposes a new method of detecting segments with high accuracy using the Hough transformation without increasing the amount of memory. Unlike the conventional segment detection method in which the detection process is based on the parameter plane, this new method feeds the process back to the image plane from the parameter plane. Another feature of the method is the elimination in the parameter plane of Hough curves which are derived from pixels in the image plane constituting already detected segments. Experiments show that this method detects segments with a high accuracy from “noisy” images including many long and short segme

ISSN:0882-1666    

DOI:10.1002/scj.4690210107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractThe learning process of macro‐operators is efficient since it is guided by given operators. By extending this method, a learning method of macro‐operators is proposed based on partial structures of explanations. Although until now macro‐operators have been used only for deductive learning that improves execution speed, the proposed method also acquires new knowledge by using hypothesis generators, i.e., it uses the explanations involving hypothesis generators to carry out induction. We demonstrate deductive and inductive aspects of our method by an example of logic circuit design and English‐Japanese tran

ISSN:0882-1666    

DOI:10.1002/scj.4690210108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractThis paper considers a new high‐efficient coding scheme of the CT image and projection data. There are two kinds of redundancies in the CT image: one is the statistical redundancy based on the correlation between pixels; the other is the deterministic redundancy resulting from the image formation process—i.e., the CT images are reconstructed from a finite number of sampled projection data. The significant information about an object in the CT image can be specified by considering the reconstruction process. Based on the investigation of such redundancies, a new reversible coding scheme of CT image with high compression ratio is proposed in which both statistical and deterministic redundancies can be remo

ISSN:0882-1666    

DOI:10.1002/scj.4690210109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY

摘要:

AbstractSyllogism (Aristotle's categorical syllogism) is a logic scheme which can describe derivation relations of propositions stating relations among quantified “terms” (corresponding to common nouns). In this system, relations of the terms are treated directly, while in predicate logic they are decomposed into relations among individual objects. Therefore, syllogism has several advantages in describing the meanings of a natural language in a formal framework of a logic system. However, the expressive ability of classical syllogism is poor in that it can treat only a proposition corresponding to a sentence whose predicate is “be” + noun (i.e., “is‐a” sentence) and cannot treat a sentence with a general verb (or “be” + adjective) in its predicate (we call it a verb sentence). Furthermore, terms in classical syllogism are only those corresponding to common nouns, and thus proper nouns, which cannot be quantif

ISSN:0882-1666    

DOI:10.1002/scj.4690210110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1990

数据来源: WILEY