摘要:

AbstractThe paper describes wafer‐scale memory design with network logic based on switching register circuit (SW‐REG), and defect tolerance schemes. Such a wafer‐scale memory is an array of chips, each consisting of a memory core and SW‐REG. The SW‐REG links neighboring chips of the same column, and each column is independently accessible from the outside. Monte Carlo simulation demonstrated that addition of driver transistors and spare lines to common signals, and bypass lines to SW‐REG are optimum defect tolerance schemes. When using 64 Mbit DRAM memory core on an 8‐inch wafer, wafer‐scale memory gives higher memory capacity than corresponding discrete chip system: for 5 percent memory core yield, 13 times higher memory capac

ISSN:0882-1666    

DOI:10.1002/scj.4690260201

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

年代:1995

数据来源: WILEY

摘要:

AbstractThis paper describes a new parallel algorithm for solving them‐machines,n‐jobs flow‐shop scheduling problem as well as its implementation on a distributed memory multiprocessor. The algorithm is basically a parallelization of the usual branch‐and‐bound method. It also takes advantage of the all‐search method to keep the efficiency of parallel processing reasonably high when subproblems become smaller than a certain size. The performance evaluation is done by comparing the parallel execution of this algorithm on the nCUBE2 multiprocessor and the sequential execution of the branch‐and‐bound with depth‐first search algorithm. The result shows that the mean speedup ratio for some conditions of the problem is more than the number of processors, and the mean speedup ratio for the conditions on which the sequential executions complete quickly is n

ISSN:0882-1666    

DOI:10.1002/scj.4690260202

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

年代:1995

数据来源: WILEY

摘要:

AbstractWe propose a system to support the human activity of understanding source code, which generates two descriptions: English‐language explanations and input‐output examples of programs. When the Prolog source code is given to our system, it extracts the basic relations are adjusted, they are converted into formal ones. Our system reconsiders these relations globally and reconstructs them. We have implemented a prototype system and have performed experiments that show the effectiveness of our approach. We discuss an extension of our approach which can be applied to procedural langua

ISSN:0882-1666    

DOI:10.1002/scj.4690260203

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

年代:1995

数据来源: WILEY

摘要:

AbstractThere has been much research in recent decades on character recognition methods, and some methods have already been put into practical use. There are many unresolved problems, however, with respect to handwritten character recognition as composed with printed character recognition. The authors considered discriminant functions, which constitute the most important part of a character recognition method. As a result of considering problems of conventional statistical discriminant functions, the authors propose applying the fuzzy theory to discriminant functions. The so‐called fuzzy discriminant function is capable of representing a data distribution in a more flexible manner because it consists of membership functions on the principal axes of learning samples.The authors conducted recognition experiments for handwritten characters with two types of membership functions. In one type the membership values are directly tuned based on human experiences; in the other they are derived from histograms or statistical data. With the former membership function, the recognition rate of 99.0 percent is achieved for [numeric] characters from the handwritten alphanumeric data base ETL6, and with the latter, the rate of 96.0 percent for [hiragana]characters from handwritten educational [kanji] data base ETL8. This result proves the effectiveness of the fuzzy discriminant function. It also indicates that a dynamic combination of human experiences and statistical techniques is a key to practical system

ISSN:0882-1666    

DOI:10.1002/scj.4690260204

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

年代:1995

数据来源: WILEY

摘要:

AbstractTo estimate the motion and deformation of nonrigid objects accurately from image sequences, this paper proposes a method for nonrigid motion tracking based on smoothness constraints, which have an effect on noise reduction in optical flow computation by a gradient‐based method. The motion of nonrigid objects generally is assumed to be smooth according to such physical properties as inertia and elasticity. Therefore, such smoothness constraints are defined in space (in frame) and time (between frames) as an active net model in formulating an energy functional and Lagrange equation, and the optical flow field derived from image sequences by shape preservation and natural deformation is modified. In addition, applying continuous Kalman filtering theory for long sequences of image frames, it is possible to estimate the temporal continuous deformation of elastic objects. The nonrigid motion tracking is demonstrated by experiments involving the modification of the shape distortion yielded by noise and the reconstruction of the real motion and deformatio

ISSN:0882-1666    

DOI:10.1002/scj.4690260205

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

年代:1995

数据来源: WILEY

摘要:

AbstractAn MRI simulator is a tool for understanding MR phenomena and developing new pulse sequences, which determine picture quality and information included in MR signals. Conventional simulators calculate the Bloch equations approximately to reduce the computation time. This paper presents a technique for solving the equations exactly at high speed and for creating images. The processing time is made practical by using the transition matrix method and the periodicity of the magnetization.

ISSN:0882-1666    

DOI:10.1002/scj.4690260206

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

年代:1995

数据来源: WILEY

摘要:

AbstractIn MR angiography, which is effective for screening of aneurysms, investigation for the quality of high‐resolution angiography method using the combination of asymmetric measurement with half scan reconstruction are presented. In addition to avoiding the flow void by the asymmetric measurement, it was found that there were improvements of: (1) blood contrast by isolation of small vessels and static regions; (2) blood continuation by interpolation in 3‐dimensional space; and (3) relative S/N of small vessels with the increasing resolution. Experimental results show that good contrast image is obtained by this method with no penalty of scanning t

ISSN:0882-1666    

DOI:10.1002/scj.4690260207

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

年代:1995

数据来源: WILEY

摘要:

AbstractWhen solving optimization problems on Hopfield neural networks, good solutions are not obtained due to convergence to local minima of the energy function. The Boltzmann machine can escape from local minima because of its stochastic behavior, but the computation time is very long to reach the (semi‐) global minimum.To avoid these problems, this paper proposes an efficient algorithm for solving optimization problems by the use of binary Hopfield neural networks. This algorithm selects a neuron which reduces the energy function value the most to reduce the energy of the network efficiently. Those algorithms are applied to the traveling salesman problem (TSP) with 10 cities. Near‐optimal solutions were obtained more efficiently than an ordinary TSP algorithm because the energy level of the network can reach lower energy states. The computation time was reduced by one order of magnitude because the energy level of the network reached lower energy states much faster than an ordinary TSP algori

ISSN:0882-1666    

DOI:10.1002/scj.4690260208

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

年代:1995

数据来源: WILEY

摘要:

AbstractThe trie has the feature that the retrieval can be executed with the character symbols composing the key as the unit, and a high‐speed retrieval is realized independently of the total number of keys. Consequently, it used frequently in the search of the natural language dictionary and in other problems. A problem, however, is that the number of trie states increases with the enlargement of the key set, which necessitates a larger memory capacity. To remedy this point, DAWG (Directed Acyclic Word‐Graph) is proposed, where the common suffix of the tries is compressed.Then, a new problem arises in that the record information cannot be determined uniquely for the key. For this problem, this paper introduces a new structure, where the number of states is reduced by merging the common suffixes of the tries, while determining uniquely the record information for the key. The algorithm for retrieval, insertion and deletion of the key is proposed for the structure. In the proposed method, the set of keys is represented using two tries. One of the tries memorizes the prefix of the minimum length that can discriminate uniquely between the key from other keys. The other trie stores the suffixes of the remaining keys in order to merge the common suffix. A simulation is executed for various sets of keys such as Chinese character called Kanji, alphabets and Japanese Katakana characters, and it is seen that the number of states is reduced by approximately 30 to 65 percent for the key set of 50,000 words, compared to the ordinary t

ISSN:0882-1666    

DOI:10.1002/scj.4690260209

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

年代:1995

数据来源: WILEY

摘要:

AbstractNumerous studies have been made on the method of constructing the distributed‐type associative memory. This paper discusses the method which selectively memorizes or memorizes by consolidation the information stored in multiple associative memories in a new associative memory.In the distributed associative memory, the information (vector) to be stored is memorized in a distributed way in the form of a matrix (called memorization matrix). Then, in general, it is difficult to know precisely the original memorized information from the already constructed associative memory.This paper proposes a method which can realize the selection and consolidation of the memorized information by constructing directly the memorization matrix of the new associative memory, using the memorization matrices of the already constructed multiple associative memories. The proposed method has the feature that it is not necessary to derive the information memories in each associative memory or to reconstruct the associative memory from the start using the memorized information (relearning). It is a requirement which arises frequently in the construction, update and use of the associative memory to memorize selectively or in a consolidated form the information memorized in multiple associative memories, in an associative memory. For such a purpose, the proposed method will be usefu

ISSN:0882-1666    

DOI:10.1002/scj.4690260210

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

年代:1995

数据来源: WILEY