摘要:

AbstractThe self‐test of built‐in RAMs is an excellent method to simplify the testing of VLSI. This paper considers the built‐in self‐test using the linear feedback shift registers on the pseudorandom input generator and the output signature analyzer. It is demonstrated that the method is useful in testing RAM embedded in VLSI. First, the random test required for testing the functional faults of RAM is analyzed, indicating that the random test can be applied to the embedded RAM. Then a built‐in self‐test for the embedded RAM using the linear feedback shift registers is proposed. Finally, the fault‐detection capability of the proposed test method is demonstrated by a comput

ISSN:0882-1666    

DOI:10.1002/scj.4690211201

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

年代:1990

数据来源: WILEY

摘要:

AbstractIt is important to improve the quality of NMR images, since this significantly affects medical diagnosis. This paper describes an image processing to improve NMR images. It is important for such improvements to utilize the image property of interest. This paper shows that noises in an NMR image have a Rayleigh distribution (e. g., they have a spike shape). To reduce this type of noise, this paper proposes an adaptive nonlinear digital filter which is adaptive to isolated status of a noise based on its standard‐deviation distribution. This standard deviation of the noises is another feature of the NMR image. The usefulness of the proposed filter is confirmed by comparing this with conventional filters. Significant improvements of image quality using this filter are demonstrated by applying it to an NMR image of a human hea

ISSN:0882-1666    

DOI:10.1002/scj.4690211202

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

年代:1990

数据来源: WILEY

摘要:

AbstractAs a binarization threshold selection method to utilize fully edge information, a method has been proposed to select the threshold so that the edge and boundary are as close to each other as possible. In such a method, the binarization actually is performed for various threshold values, and the degree of coincidence is calculated. Consequently, a very large processing time is required. The degree of coincidence is defined as the ratio between the number of boundary points in the edge region to the total number of boundary points in the image.The authors have devised a method which can determine with a high speed the number of boundary points for each threshold without actually performing the binarization. In this method, the result of applying shrink filtering after binarization is the same as that of applying the binarization with the same threshold after applying the minimum filtering.By utilizing this property, it is shown that the difference of the cumulative histograms between the original image and the result of processing by the minimum filter is the same as the number of boundary points for the threshold. Furthermore, the following property is shown by extending the method. The degree of coincidence between the edge and the boundary is defined as a two‐variable function of the threshold of edge detection and the threshold of binarization. Then it is shown that the degree of coincidence between the two can be calculated for any threshold without actually detecting the edges and boundaries.By utilizing this property, not only the threshold for binarization of the original image but also the threshold for the differentiated image to detect the edge can be determined simultaneously in an optimal way without necessitating a large amount of computatio

ISSN:0882-1666    

DOI:10.1002/scj.4690211203

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

年代:1990

数据来源: WILEY

摘要:

AbstractTo recognize a character using a pattern matching method, it is necessary to prepare sufficiently many sample patterns for a template pattern. However, it is difficult to collect a sufficient number of samples of some characters because they do not appear often. This paper proposes a new method of estimating a template pattern using the transfer function in a frequency range which is considered generally to be useful in such a case. The effectiveness of the method is demonstrated experimentally by using the printed Devanagari characters (in Buddhist literature) as an example.

ISSN:0882-1666    

DOI:10.1002/scj.4690211204

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

年代:1990

数据来源: WILEY

摘要:

AbstractThis paper proposes an automated procedure for both the size classification and the density (profusion) classification of the pneumoconiosis radiograph. The procedure is as follows. The rounded opacities are enhanced using a second‐order difference linear filter with a circular weighting function which is designed based on the model for the shape and the density distribution of the pneumoconiosis rounded opacities. The candidates for the center of the rounded opacity are extracted, and the size classification is made by estimating the size of the rounded opacity. Then the density classification is made by measuring the density of the rounded opacity. Thus, the classification procedure is conceptually composed of three stages: (1) recognition of rounded opacity; (2) size classification; and (3) density classification. This paper concentrates on the size classification and the method is described. The result is shown with a discussion for the classification experiment using ILO international standard film. In the experiment, the recognition rate of approximately 72 percent was obtained for both the size and the density classifications, using only one feature parameter. This result indicates the usefulness of the proposed method, and an attempt is made to recognize directly the individual pneumoconiosis rounded opacity. Another feature of the method is that the weighting function is selected based on the enhancement effect of the filter. This point may be interesting as an example of the automatic parameter determination of the emphasis filter in the image processin

ISSN:0882-1666    

DOI:10.1002/scj.4690211205

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

年代:1990

数据来源: WILEY

摘要:

AbstractThe development of an automatic system which, as a means of treatment, can control the blood pressure of a patient by a continuous injection of vaso‐acting drugs is in great demand in the medical care field. However, the practical application of such a system has been postponed due to safety considerations. This paper attempts to realize the safe control of the physiological system, and a control method based on the recognition of the transition of the time‐series signal has been developed. The idea is applied to the automatic control of blood pressure. For the recognition of the time‐series signal transition, a dedicated IF‐THEN representation TMSTR (time‐sequential multiple state transition representation) is devised which includes the concepts of “state” and “time.” A method is proposed in which more than one “state” is defined for the time‐sequential data, and the transitions among states are represented by IF‐THEN rules. By this scheme, the time sequential data transition is recognized. Using the constructed representation, the physician's knowledge of the blood pressure control is represented and transplanted to the computer. Using a 16‐bit microcomputer, a closed‐loop control system is constructed. As a result of animal experiments, a blood pressure control close to that of the physician is realized, indicating the effectiveness of the proposed method in the contro

ISSN:0882-1666    

DOI:10.1002/scj.4690211206

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

年代:1990

数据来源: WILEY

摘要:

AbstractThis paper proposes a method for selecting the feature parameters in the statistical discriminant analysis of the human letter‐cognition related evoked potential. The paper aims at the quantitative interpretation of the frequency components, latency and the cortex area of the evoked potentials accompanied by the human letter‐cognition process. Models are constructed at three levels considering the awareness of the subjects: (1) classification, (2) retrieval and matching, and (3) attribute recall. To examine the validity of the models, the number of parameters is increased along the time axis to determine which addition of parameters resulted in a remarkable contribution to the discrimination. By examining the recognition rate, the necessary frequency components are determined. From the viewpoint of improving the recognition rate, methods of selecting the parameters are compared to examine the nature of the parameters selected in the method with the highest recognition rate. As a result, it is seen that the latencies in the models at three levels for the letter‐cognition process are approximately 190, 250 to 350, and 730 ms, respectively; and the necessary frequency components extend to at least 60 Hz. By comparing the selection method for the parameters, the recognition rate reached above 95 percent at the highest. It is seen that the tendency of the selected parameters is the same as those of the m

ISSN:0882-1666    

DOI:10.1002/scj.4690211207

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

年代:1990

数据来源: WILEY

摘要:

AbstractThis paper reports on the defect detection algorithm for the LSI wafer multilayer patterns, together with the result of evaluation. The multilayer patterns are constructed by the exposure after alignment between the wafer pattern and the reticle pattern for each chip. Consequently, the position relation between layers is different even for adjacent chips (interlayer registration error). The developed algorithm compares the gray‐level images of adjacent chips on the wafer and extracts the defect without being affected by the inter‐layer registration error. First, the pattern edge is extracted from the gray‐level image, and the position alignment is executed using the edges. Then, by eliminating the region where gray levels are equal, the regions are extracted for which the position alignment is unsatisfactory. The position alignment is attempted again for that region. This procedure is iterated. When the unmatched region of the pattern edge is sufficiently small, it is decided that the interlayer registration error is absorbed, and the unmatched region is extracted as the defect. An automatic visual inspection system was constructed and evaluated experimentally. As a result, it was verified that the whole chip area can be inspected, and the defect of 0.5 μm or more can be detected in a stab

ISSN:0882-1666    

DOI:10.1002/scj.4690211208

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

年代:1990

数据来源: WILEY

摘要:

AbstractFor registration between images, algorithms of point correspondence searching type and deformation field analyzing type have been proposed in the past. The former had a problem of increasing processing quantity and the latter had a problem of assuming small displacement or deformation. This paper proposes a cooperative image registration technique which absorbs finite displacement and nonrigid body deformation by iteratively applying affine transformations from coarse to fine for binary images expressed by sets of loci vectors of characteristic points. The process consists of four steps: (1) for each characteristic point of a reference image, a local affine transformation (LAT) weighted by Gaussian window functions is applied; (2) based on the least‐squares method, LAT is optimized for each characteristic point of the reference image so that overlapping for a group of characteristic points of input images becomes best; (3) optimized LAT is applied for each characteristic point of the reference image and deformed reference image is generated; (4) iterating steps (1) through (3) while gradually decreasing the spreads of the Gaussian window functions, when the deformed image coincides with the input image, displacement between images is determined. We have applied this method to binary character images including large deformation and random‐dot stereograms and obtained good results. Also, we evaluated the processing quantity by this method and showed that extension to gray scale images is easily formula

ISSN:0882-1666    

DOI:10.1002/scj.4690211209

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

年代:1990

数据来源: WILEY

摘要:

AbstractA human expert is able to determine phoneme boundaries through spectrogram reading with high accuracy using one's knowledge and strategy. The authors developed a phoneme segmentation expert system which simulates a human expert spectrogram reading process using knowledge and strategy. This expert system detects phonemes from a continuous speech spectrogram and determines phoneme boundaries with their coarsely classified phoneme according to human expert knowledge and strategy which is described as rules. An assumption‐based inference with certainty factors and top‐down acoustic feature extraction under phoneme context hypotheses are incorporated into the expert system to simulate the phoneme contextual fuzzy knowledge and strategy used by a human expert. This framework makes it possible to deal with phoneme variations caused by coarticulation, and to extract accurate acoustic features on a spectrogram for phoneme segmentation. Japanese consonant segmentation knowledge currently is incorporated into the system which detected 90.8 percent of the phonemes correctly. In particular, the average alignment error of phoneme boundaries detected by the system was 5.8 ms, which is as accurate as those detected by a human exp

ISSN:0882-1666    

DOI:10.1002/scj.4690211210

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

年代:1990

数据来源: WILEY