摘要:

AbstractNew two‐dimensional nonrecursive digital filters are proposed for noisy blurred images. A two‐dimensional nonrecursive filter is developed to minimize the mean‐squared error of the restored image. Here, the point spread function of the blurring system and statistics of the original image and noise are assumed to be given. A simplified version of the above filter is also developed and tested for restoring images blurred by a linear blurring system. As a result of their nonrecursive nature the proposed filters are stable and are determined by solving linear systems of equations. The blur by the point spread function and that due to degradation by noise are considered in the design of the filters. Images can be restored while the accompanying noise is suppressed. The filters herein are shown to be more effective if combined with noise‐removal filters. Illustrative examples are included to demonstrate the excellent quality of images restored by the proposed

ISSN:0882-1666    

DOI:10.1002/scj.4690160501

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

年代:1985

数据来源: WILEY

摘要:

AbstractA speaker‐independent word recognition based on multiple word templates is described using the SPLIT method. Since the spectral distance calculation amount is independent of the number of word templates in the SPLIT method, it can be made best use of in speaker‐independent word recognition based on multiple word templates.Phoneme‐like templates and multiple word templates are selected automatically by a clustering technique. The effectiveness of this system was verified via several experiments using telephone switch. Recognition accuracy of 96.9 and 96.2 percent was obtained for training and test speech samples, respect

ISSN:0882-1666    

DOI:10.1002/scj.4690160502

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

年代:1985

数据来源: WILEY

摘要:

AbstractWe propose a method of decomposing an automaton which represents the flow of a program into simpler automata. More specifically, we: (1) introduce a new automata model called paired synchronized automata; (2) present a polynomial time algorithm for decomposing an automaton into paired synchronized automata; (3) show the correctness proof of the algorithm; and (A) give an experimental result on the effect of the decomposition algorithm for a certain application. In the proposed model of paired synchronized automata, each automaton contains a synchronization symbol to describe the action of sending a signal to and receiving it from another automaton, and for any external input, multiple transitions are prohibited. The paired synchronized automata produced by the proposed decomposition method are much simpler than the automata produced by the previous method, and they are easy to be translated in a program.

ISSN:0882-1666    

DOI:10.1002/scj.4690160503

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

年代:1985

数据来源: WILEY

摘要:

AbstractThe rotation delay of a disk caused by RPS‐miss, which is larger than what is usually assumed to be, is nonnegligible in. systems of heavy load. A method is proposed to cope with this delay by improving the response time and throughput: a buffer‐contained disk unit. Its performance evaluation is shown by simulation. The buffer‐contained disk unit has a small amount of buffer (some tens of kB). Data transmission between a buffer and a disk control unit and disk rotation occur asynchronously, which considerably reduces the delay time. In writing operation, the seek time is overlapped by data transmission time, and seek and rotation delay time appear to be zero. In simulation, an access pattern of real system is used which is obtained by tracing the disk input/output operation. Hence, the response and throughput are clearly improved by 1.7±3.8 times and by 2.0±3.3 times, respectively. The method can be applied to a large variety of disks with great performance improvement and little add‐on

ISSN:0882-1666    

DOI:10.1002/scj.4690160504

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

年代:1985

数据来源: WILEY

摘要:

AbstractThis paper proposes a construction method for the large‐scale multiprocessor system, which is composed of a large number of processors and memories. There can be two configurations for the large‐scale multiprocessor systems. One is the configuration composed of the switching network among processors and memories, as is seen in the case of the omega network. The other is the processor network which is the graph composed of processors, with the processor being regarded as a node. The interconnection network proposed in this paper belongs to the latter category. It is a VLSI‐oriented interconnection network, where the multiprocessor system is implemented on a silicon wafer. The method of construction is developed from the viewpoint of factual geometry, where self‐similarity is considered among figures. The basic unit of the interconnection network is the structure composed of the processor, memory and bus. The system is constructed by recursively using the basic units. To compare the proposed system with other typical VLSI‐oriented interconnection networks, such as the tree and the snowflake interconnection networks, the maximum distance between processors, the mean distance between processors and the maximum message density, which is considered as the maximum communication load for the routing and node processors, are calculated.The result verifies the effectiveness of the proposed interconnectio

ISSN:0882-1666    

DOI:10.1002/scj.4690160505

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

年代:1985

数据来源: WILEY

摘要:

AbstractThis paper discusses problems in the implementation of interrupt handling in the loosely synchronized Triple Modular Redundancy (TMR) system where synchronization, majority‐decision and fault diagnosis are performed by software. The method of solution for the problems also is discussed. The major problems are as follows: (1) For the interrupt coming into three processors with a certain time difference in the task progress, the consistency among the global areas of the processors must be maintained; (2) The synchronization must be maintained among processors, which do not recognize interrupts due to the interrupt‐inhibit period containing synchronization, and the processors, which recognized the interrupts; (3) When interrupts at different levels arrive at a processor, each processor must identify the interrupt with the highest priority consistently. To solve these problems, we have developed a multitask scheduler, which provides the variable representing the number of access to the global area, the flag indicating the interrupt‐inhibit area, and the variable keeping the record of the accepted levels. This scheduler also controls the interrupt process by mutually referring those variables and flags. The system is implemented in SAFE system, and the overhead in the interrupt handling was mea

ISSN:0882-1666    

DOI:10.1002/scj.4690160506

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

年代:1985

数据来源: WILEY

摘要:

AbstractA new method is considered which integrates the READ scheme and the line skip scanning scheme, and nonreversible coding, which provides as good image quality as reversible coding. A binary document image was used. Its basic idea consists of decomposing the object image into small regions and examining the reconstructability of the image for each small region.It is expected that a high compression ratio will be achieved by changing the scanning density based on the results. Now, the change of scanning density is accomplished by line skip scanning and skipped line ranges from 1‐3. Also, the reconstructability of the image is determined by the strength of correlation which is examined by the relative distance distribution among the scan lines corresponding to the number of each skip line. As a result of experiments on ten kinds of test charts including the CCITT test chart, the compression ratio is 1:5.05 to 1:54.3. Therefore, in comparison with the READ scheme, about 59.7 percent of the compression ratio is improved. Also, it has been shown that 99 percent of all transmitted pixels is reconstructed exactly in terms of reconstruction accurac

ISSN:0882-1666    

DOI:10.1002/scj.4690160507

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

年代:1985

数据来源: WILEY

摘要:

AbstractAs models to describe the concurrent systems with synchronized mechanism, synchronized shuffle grammar and synchronized production system (SPS) have been proposed. The synchronized shuffle grammar is defined by the triplet composed of a shuffle grammar G, synchronizing language LCand a homeomorphism h. The language generated by is defined as L(G) = h (L(G) LC). As a subclass of the synchronized shuffle grammar, this paper considers a class syncRSG (sync ERSG), where G is an (extended) regular shuffle grammar and Lc is an arbitrary regular language. SPS can also be defined as a pair of extended context‐free grammar and a state‐transition machine. This paper considers as its subclass, the context‐free SPS which is a pair of a context‐free grammar and a finite automaton. It is shown that there exist some subclass.es in syncRSG (sync ERSG) and context‐free SPS, which generate the same class of formal languages. It is also shown that there exists a certain hierarchical relation, and the full descriptive powers of syncRSG (syncERSG) and context‐free SPS are the equivalent to that o

ISSN:0882-1666    

DOI:10.1002/scj.4690160508

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

年代:1985

数据来源: WILEY

摘要:

AbstractA database machine is required at present which can process with high speed the complex query to the large‐scale database. We are now developing a high‐performance database machine which can cope with such a requirement. Part of the machine for relational algebraic processing is called GRACE. GRACE is a parallel machine with a multimodule structure, and the interconnection networks among its components are important. From a functional viewpoint, the interconnection networks of GRACE can be divided into the bucket distribution network, which sends data into the staging space, and the bucket collection network, which sends data into the set of processors. This paper proposes the control scheme for the data flow in the bucket collection in GRACE, as well as a method of realizing the bucket collection network. The validity of the proposal was verified by evaluation and examination using simulation. To utilize the features of the processing scheme of GRACE, the indirect binary h‐cube network is used as the interconnection network, which is a kind of multistage interconnection network. A very low transfer overhead was realized. Furthermore, the partitioning of the interconnection network for parallel operations is disc

ISSN:0882-1666    

DOI:10.1002/scj.4690160509

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

年代:1985

数据来源: WILEY

摘要:

AbstractThe SEC‐DED‐SbED code is capable of correcting a single‐bit eror, detecting a random double‐bit error and detecting a b‐bit block error. It is expected to be widely used for highly reliable semiconductor memory systems composed of memory devices with b‐bit output.In this paper a new theoretical construction method for SEC‐DED‐SbED codes is proposed. The proposed class of codes is so characterized that, with byte length b, it is constructed from conventional SEC‐DED‐SbED codes of byte length b/2 and the weight of the column vector of its parity check matrix H (the number of l's) is odd. The bit length n of the code is given as n _ b2(r‐b) . r/2Cb/2 bits, when the check bit length r and the byte length b are even. It has the longest bit length among the known code classes in a large

ISSN:0882-1666    

DOI:10.1002/scj.4690160510

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

年代:1985

数据来源: WILEY