bluuebunny/crossref_metadata_2025 huggingface dataset:
SPC with correlated observations for the chemical and process industries
Authors: Mastrangelo Christina M. , Montgomery Douglas C.
Published: July 2007

In the use of statistical control charts, violating the basic assumption of independent or uncorrelated data results in a chart that exhibits poor statistical performance, resulting in an increased number of false alarms. Autocorrelated data requires modifications to traditional control chart techniques. A method based on the exponentially weighted moving average that uses variable control limits is presented. Using simulation, we explore the shift detection properties of this moving centre‐line technique and will show how the detection capability of the procedure can be enhanced using supplemental tracking signal tests. Guidelines and conditions for use are also presented.
Fault‐tolerant processor interconnection networks
Authors: Imase Makoto , Soneoka Terunao , Okada Keiji
Published: July 2007

As suitable topology for interconnection networks of multiprocessors, De Bruijn graphs have been proposed and a number of investigations have been conducted on their fault tolerance. A De Bruijn graph is a directed graph with maximum degree d (the maximum number of links that can be connected to one processor), diameter k (maximum number of repeaters between two processors) and number of nodes dk (number of processors). A Kautz graph is a directed graph with maximum degree d, diameter k and number of nodes dk + dk‐1. Both have the smallest diameter among the graphs with maximum degree d. This paper proves the following: (1) If d ‐2 nodes in a De Bruijn graph are removed (if d ‐2 processors are faulty), its diameter becomes d + 1, which is only 1 larger than the original diameter. (2) If d ‐3 nodes in a Kautz graph are removed, its diameter becomes k + 1 and if d ‐1 nodes are removed, the diameter is k + 2 or less, which is at most 2 larger than the original diameter. (3) The values of (1) and (2) are at most 1 larger than the lower bound under the limitation of degree d, (4) A fault‐tolerant routing algorithm can be realized easily. This algorithm is better than any existing algorithm because of its short routes.
A new line data management structure suitable for geometrical retrievals based on spatial relations
Authors: Ohsawa Yutaka , Sakauchi Masao
Published: July 2007

With the recent widespread application of computer graphics, a management system for graphic data is required which is suited to interactive processing. This paper discusses the management structure for the line data, which can realize a retrieval in an efficient way according to the spatial relations. The dynamic data management structure called the BD time, which was developed by the authors for the multidimensional point data management, is employed. In the proposed system, the BD tree is modified into a form (nonpacket type) suited to high‐speed processing, and is extended to suit the line data. In this system, the segment is managed by its centroid and the circumscribed quadrilateral. The BD tree is composed of a set of centroids, where each node has information concerning the circumscribed quadrilaterals for all segments in the subtree. The retrieval is made efficient by the information concerning the circumscribed quadrilateral. In this paper, the data structure for the line data management is discussed first. Then various retrieval algorithms which depend on the spatial relations according to each application are discussed in detail. Finally, the usefulness of the proposed data structure is demonstrated by a retrieval experiment of actual geographical data.
Reconfiguration of a fault‐tolerant rectangular systolic array
Authors: Suzuki Yoshinao , Hirata Tomio , Imai Masaharu , Yamashita Masafumi , Ibaraki Toshihide
Published: July 2007

Fault‐tolerant designs which incorporate redundancy to improve the yields of VLSI chips are well known. In such designs flaws in a chip are excluded by reconfiguration. This paper discusses the reconfiguration problem of a rectangular systolic array: Given a rectangular systolic array, construct a flawless array of maximum size. Three levels of constraints on reconfiguration are considered, and for each constraint the problem is proved to be NP‐complete and an approximation algorithm is proposed.
Signal processing approach to optimum preprocessing for on‐line recognition of handwritten japanese characters
Authors: Aizawa Tadashi , Nakagawa Masaki , Takahashi Nobumasa
Published: July 2007

With the recent tendency toward miniaturization and price‐down of tablet digitizers, they are expected to be used as the input device for handwritten characters and drawings. As the preprocessing for the point coordinate sequence read from a tablet, only empirical methods have been applied. This paper discusses the preprocessing from the viewpoint of signal processing, and a quantitative evaluation was made for the following two points: (1) directional stability of the preprocessed coordinate sequence; and (2) follow‐up (fidelity) of the preprocessed point sequence to the original point sequence. As a result, a performance superior to the traditional methods was obtained by the following four phases: 1 Adaptive sampling, where sharp corners are stressed, while the sampling points are set uniformly for slow pen movement; 2 interpolation, where the point interval is made uniform for fast pen movement; 3 smoothing by the moving‐average filter; and 4 thinning to eliminate redundant points. The point sequence after the proposed preprocessing has the following features: (1) The original point sequence is followed, being little affected by the pen speed; (2) the directional stability is achieved even for 32 directional quantizations in the straight‐line segmentation used by the authors; and (3) features such as sharp corners are preserved.
Coordinate rotation invariance of image characteristics for 3d shape and motion recovery
Authors: Kanatani Ken‐Ichi
Published: July 2007

In order to determine the shape and the motion of the object from its projection, it suffices to derive and solve the equation relating the parameters specifying the shape and the motion of the object with the features measured on the image. The equation is usually nonlinear, and is difficult to solve in the analytic way. This paper notes that there is no inherent coordinate system on the image, and any two coordinate systems are equivalent. By combining the features of the image, coordinate‐rotation‐invariant parameters (invariances) are derived. By this scheme, the geometrical meaning of the image characteristics is made clear, and the analytic solution is obtained in a natural way. The idea is demonstrated for the cases of the optical flow analysis and the surface recovery by texture, as examples.
Application of df/ihs to minimum total weighted flow time multiprocessor scheduling problems
Authors: Kasahara Hironori , Kai Munenori , Narita Seinosuke , Wada Hidehiko
Published: July 2007

In most cases, the scheduling problem for the multiprocessor system is NP‐ or strong NP‐hard. For this problem, we have already proposed a practical optimization algorithm DF/IHS (Depth First/Implicit Heuristic Search), which combines the list‐scheduling algorithm and the depth‐first search, for the minimum parallel processing time multiprocessors scheduling problem. This paper presents a result of application of DF/IHS to the minimum total weighted flow time problem, which is used in the optimization of memory utilization. The problem of allocating tasks to m processors is considered with or without precedence constraints among the tasks. It was verified that the DF/IHS can be applied to this kind of problem very effectively, where the optimal or highly accurate approximate solution is obtained for the large‐scale problem with several hundreds of tasks.
IMPRESS: A system for image processing procedure construction based on sample‐figure presentation
Authors: Hasegawa Jun‐Ichi , Kubota Hiroaki , Toriwaki Jun‐Ichiro
Published: July 2007

As a method of dialog with users, earlier image processing systems used a combination of linear information and words, a number or a phrase for description. However, these systems were limited in providing actual detailed descriptions of the extraction of image border and border lines.

Thus a new Image Processing Expert System, IMPRESS, is proposed in this paper. This system accepts sample figure presentations which include an automatic process for selecting a figure that most closely identifies the sample figure without reading a description of the processing purpose. In addition, this system can be realized by using actual cases of construction.

This paper explains the basic concept of this system and the automatic construction method of the line pattern extraction procedure. The method is then applied to the problem of major outline extraction of chest X‐ray images, and its effectiveness is shown.
A video tape production system with digital captions in a code format for the deaf
Authors: Nishikawa Satoshi , Takahashi Hidechika , Kobayashi Masayuki , Kabe Katsuhiro , Takiguchi Tsutomu
Published: July 2007

The authors have been involved for 8 years on R&D as well as improvement of the production system for videotapes with digital captions for the deaf, using Japanese word processors. A prototype was developed in July 1982, and a pattern information synthesizer VIP (video information processor)‐2000 was developed in April 1983. Captions which are almost faithful to the speech of the performer were synthesized into the scene of the program, and the results were almost satisfactory. However, a certain time was needed to synthesize the caption with the video scene, which produced a delay between the caption and the mouth movement. Sometimes, the captions were difficult to read depending on the background, since no vertical edge was provided. To solve these problems, the VIP‐4000, which is a coded information synthesizer, was developed. As a result, the time for caption synthesis is reduced drastically and the vertical edge is provided. Furthermore, coloring of the characters and inhibition rules can be applied, which helps the visual sensation. This paper describes the hardware, software, features, and performances of the VIP‐4000.
Filtered back projection method for cone‐beam X‐ray CT
Authors: Matsuo Hiroshi , Horiba Isao , Iwata Akira , Suzumura Nobuo
Published: July 2007

This paper investigates filtered back‐projected algorithms for come‐beam X‐ray CT reconstruction. A two‐dimensional detector array and a cone‐beam X‐ray source mounted on opposite sides of a cylindrical frame rotate 360 degrees about the object under observation to derive the projection data as a function of the absorption coefficient of the object. A modified ρ filter is proposed for enhancing the incomplete projection data before three‐dimensional reconstruction. The modified ρ filter provides two major enhancement functions: (1) It compensates for error in CT value (due to oblique components of X‐ray beam) by filtering the data in both the rotation direction and the direction of the axis of the rotation; and (2) recognizing the incompleteness of projection data in the frequency domain, the filter controls the spatial resolution along the axis of the rotation to reduce the amount of artifact in the reconstructed image. The applications and effectiveness of the modified ρ filter were estimated by computer simulation.
Compound decision theory and adaptive classification for multispectral image data
Authors: Watanabe Takashi , Suzuki Hitoshi
Published: July 2007

Previously, we reported on the experimental evaluation of multispectral image classifiers utilizing local spatial information. It was shown that the two classifiers of compound decision and adaptive classification exhibit a good performance in terms of the discrimination rate and the processing time. This paper discusses the improvements of those two methods further to improve the discrimination rate, and presents the result of experiment to indicate the effectiveness. More precisely, the following improvements were made. For the compound decision, the improved method estimates the context distribution based on the dependency of three pixels. For the adaptive classification, an extended adaptive classification is newly proposed where the adaptibility is improved by extending the region for classification to shapes other than a square. Among those, the extended adaptive classification is shown to be a highly practical method, wherein the discrimination rate is much higher than in the pixelwise classification such as Bayes decision, and it is expected to be employed widely as the standard classification method.
Liquid crystal range finder—a high‐speed range‐imaging system using liquid crystal shutter
Authors: Sato Kosuke , Inokuchi Seiji
Published: July 2007

The range image measured by the structured light projection has a merit in that the high‐density three‐dimensional data of the object can be obtained with a high speed, in a stable way and without ambiguity, independently of the smoothness of the object. In this study, a high‐speed driven structured light projector is realized by applying a liquid crystal shutter to the projection system. By incorporating the technique with the Gray code pattern projection spatially coded three‐dimensional measurement system, a highspeed range‐imaging system (Liquid Crystal Range Finder) is constructed. For the liquid crystal range finder, several elaborations are presented, such as stabilization of the measurement and improvement of the accuracy. As to the stabilization, a projection pattern extraction method is developed which excludes the effect of the texture of the object surface or the effect of the environmental illumination, using two complementary projection patterns. As to the improvement of the accuracy, the following elaborations are made. A double‐precision pattern is generated by shifting the liquid crystal shutter by a half‐pitch, utilizing the feature of Gray code pattern. The projector coordinate is determined with a high accuracy by the interpolation of the spatial code and the interpolation of the projection pattern boundary based on the gray level of the pixel. The usefulness of those techniques is demonstrated by actual measurement.
Distributed database concurrency control by cautious schedulers with a central clock site
Authors: Nonmember Jigui Li, , Ibaraki Toshihide
Published: July 2007

In [5], a concurrency control of the distributed database system by the cautious scheduler was proposed where the time stamp also is issued by the distributed algorithm. By contrast, this paper proposes a new concurrency control, assuming a central clock site issuing the time stamp. Compared with the previous method, the features of the present method are that the communication requires fewer messages and is simple. For typical faults, methods of remedy are discussed.
Stability of neural networks and convergence of their sensitivity computation algorithms
Authors: Member Kiichi Urahama
Published: July 2007

This paper considers the continuous‐time model and the discrete‐time model for the neural network, and discusses the stability of the model and the convergence of the sensitivity computation algorithm. First, a sufficient condition is given for the global asymptotic stability of the model. Then the speed with which the solution approaches the equilibrium is evaluated. Based on the results obtained, the local asymptotic stability of the equilibrium solution of the multi‐stable circuit is discussed. The fault‐tolerant property of the model is discussed briefly. Finally, it is shown that under the same condition as the sufficient condition for the asymptotic stability of the model, a certain kind of general sensitivity computation converges in the global sense.
Syllable recognition using integrated neural networks
Authors: Matsuoka Tatsuo , Hamada Hiroshi , Nakatsu Ryohei
Published: July 2007

This paper describes a new syllable recognition method using the integrated neural network (INN). In this method, the recognition targets are partitioned into several groups. INN consists of a control network and several subnetworks. The control network identifies to which group the input speech belongs, and the subnetworks recognize the syllables within each group. Using INN, even if the recognition scope is large, or even if there are few training samples, the network can recognize syllables with higher recognition accuracy than conventional back‐propagation networks. Furthermore, new vocabulary entries can easily be added to an INN by adding new subnetworks corresponding to the new groups. Using the grouping method based on the manner of the articulation of consonants, the recognition accuracy is 96.2 percent for INN, compared with 95.8 percent for the conventional network architecture. This higher accuracy is obtained with 40 percent lower training costs. Using the grouping method based on the hidden layer activation patterns of a network which has learned to recognize all syllables, the accuracy is 96.0 percent.
A method of generating template patterns from a few sample patterns in character recognition
Authors: Suzuki Akihiro , Makino Shozo , Kido Ken‐Iti , Kanai Hiroshi , Kawazoe Yoshiyuki
Published: July 2007

To 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.
Improved complex demodulation method for frequency analysis
Authors: Li Hao Ying , Ueda Yoshikazu , Ishii Naohiro
Published: July 2007

Sleep spindle brain waves have an important role in the sleeping mechanism. Recently, computer‐aided automatic analysis methods have been introduced in the form of numerical analysis of frequency, duration, etc., and their rapid progress has been noted. However, the spindle waves are transient nonstationary “phasic events,” and therefore their accurate frequency analysis has caused serious difficulties.

Aiming at the accurate frequency analysis of the spindle waves, the authors have already proposed an analysis algorithm based on complex demodulation (CD) in the time domain, but the long processing time required for the analysis has remained a problem.

This paper proposes a new analysis algorithm which combines the advantages of frequency domain CD and Hilbert transformation. This method applies Hilbert transformation mainly to speed up the measurement of instantaneous amplitude and, in the case of measuring the instantaneous frequency, the advantage of the CD method using interpolation is exploited to improve the accuracy. Here, the proposed method is explained concretely and the analysis results are investigated in comparison with the time domain CD method published earlier.
Design of a robust fault‐tolerant multiplier
Authors: Kasuga Takeshi , Kameyama Michitaka , Higuchi Tatsuo
Published: July 2007

This paper presents a construction of a robust fault‐tolerant multiplier aiming at high safety, where the output does not differ much from the normal value, even if a temporary fault is produced in the operation unit. For this purpose, a robust fault‐tolerant divider circuit by a fixed positive constant is devised, which is called divider. The multiplier is constructed by arranging such dividers in parallel. The proposed robust fault‐tolerant multiplier is based on the distributed coding, where the input/output information is always represented by the number of pulses. Consequently, a system‐down is not produced even if more than one temporary error is generated, which is different from the majority redundant circuit. Another feature is that there is no hardware core, such as the majority‐decision circuit for the output signal selection, and a temporary error does not produce a system‐down.
A compression algorithm for medical images and a display with the decoding function
Authors: Gotoh Toshiyuki , Nakagawa Yukihiro , Shiohara Morito , Yoshida Masumi
Published: July 2007

This paper describes an efficient compression method for medical images and a high‐speed display with a decoding function. An image is divided into blocks first and then whether each block has sharp edges is examined. The discrete‐cosine‐transform coding (DCT), which is efficient for a part having small gray‐level variation, is applied to a block having no sharp edge. The block‐truncation coding (BTC) which preserves sharp edges is applied to a block having edges, and then the DCT is applied to their error images.

This combined procedure makes a reconstruction of the whole image in a high quality. The display developed by the authors receives the compressed data from a host computer and reconstructs images of good quality at high speed using four pipeline‐based microprocessors based on their method. Experimental results show that the image quality of parts without sharp edges is as high as the DCT method; and that of parts with edges is better than the DCT and BTC methods.

The whole process, which includes transferring data from the host computer to the display, reconstruction, and display of the data, took less than 5 s for a 1/10 compressed image. This demonstrates an excellent performance of the proposed reconstruction display.
Optimizing universal queries in relational databases
Authors: Ito Minoru , Kasami Tadao
Published: July 2007

In a relational database system based on the universal relation interface, users do not have to specify access paths when constructing universal queries. Moreover, users cannot control how to evaluate the queries efficiently (though they can construct usual queries, such as relational algebraic expressions, considering their processing costs). Thus, it is important for the system to evaluate given universal queries efficiently. This paper considers the representative instance of a database as a universal relation, and presents an optimization algorithm for evaluating a universal query for computing specified components of the tuples in the universal relation which satisfies a specified condition.
A high‐speed labeling algorithm for raster‐scanned type
Authors: Okuyama Yoshiyuki , Kobayashi Yoshiki , Takenaga Hiroshi , Asada Kazuyoshi , Fujiwara Kazunori
Published: July 2007

Labeling is a procedure by which labels are assigned separately to a number of connected components, and it is also one of the important functions in the image processing system. In the conventional raster‐scanned labeling, labels are assigned temporarily in a small local area. Then a large number of temporary labels (pairs of connected labels) is generated for the same connected component, and a long processing time is required to unify and transform them into the final label.

From such a viewpoint, this paper discusses the reduction of processing time for the unification of pairs of connected labels. As a result, it is concluded that the following two approaches are effective:

Simplify the table structure for storing the pairs of connected labels

Reduce the generation of the pairs of connected labels.

The following MIN‐MAX method is devised as a means to realize (1). In the table storing the pairs of connected labels, MAX of the two temporary labels forming the pair of connected labels is adopted as the address, and MIN is used as the content data. To realize (2), it is noted that the concave and indented connected components often produce the pair of connected labels. The pixel‐embedding and the forward pixel referring methods are devised for such situations. This paper presents the algorithms for those methods, and reports on the result of evaluation.
Deadlock prevention and avoidance methods using timestamps for locking control in distributed database systems
Authors: Kobayashi Tetsuji
Published: July 2007

Locking is used widely for concurrency control in database systems, and locking methods are categorized as static locking or dynamic locking. For distributed database systems, this paper proposes a new deadlock prevention method for static locking and a new deadlock avoidance method for dynamic locking. The common advantages of these methods are as follows: (1) system performance is improved by using time stamps; (2) since transactions are executed without explicitly using time‐stamp ordering, after a transaction lock is permitted, even when another transaction with a smaller time stamp arrives, the rollback of the transaction is unnecessary; and (3) since time stamping is used only for deadlock resolution, the proposed methods can easily be introduced to existing distributed database systems that use locking control.
High‐precision t1 imaging method for magnetic resonance imaging
Authors: Satou Shinichi , Sano Koichi , Yokoyama Tetsuo , Koizumi Hideaki
Published: July 2007

It is expected in magnetic resonance imaging (MRI) that the measurement of the longitudinal relaxation time (T1) will be useful in the diagnosis of cancer and in the tissue characterization. The present problem in this regard is the deterioration of the accuracy due to the various factors such as the rotation angle error of 180 deg pulse and the finite repetition time for imaging.

From such a viewpcint, this paper derived an expression for the signal intensity for the inversion recovery image (IR image) considering those factors, and it is shown that a highly accurate T1 image with small error can be constructed by the proposed method from at least three images with different inversion times. Then a simplified method is proposed which can derive analytically the T1 image from three IR images obtained without using the iterative calculation, by controlling the inversion times so that they form an arithmetic progression. It was verified by a computer simulation that the error in the T1 image due to the forementioned factors can be kept below 1 percent by the proposed method. Using the MRI system, the T1 image as well as the proton density (rH) image are obtained from a copper‐sulfate phantom. The error between the object and the reconstructed image, which has been as large as 7 to 15 percent, is now suppressed to approximately 1 percent by the proposed method. Thus, the accuracy improvement in T1 and rH images is verified.
3‐D shape reconstruction of human face from a 2‐d facial image and provision for change of expression
Authors: Komatsu Koji
Published: July 2007

Various studies are presently being made on the facial image (e.g., highly efficient coding and the discrimination of faces) for computer animation and TV conference systems. This paper describes a method in which the three‐dimensional (3‐D) shape of the face is estimated from a single 2‐D facial image, and the expression or the direction of the face can be modified. The original 2‐D facial image need not be taken from the front, and the image from any direction can be used. The curved surface model, not the usual polyhedron model, is employed as the 3‐D shape model.

The surface model generates the curved surface passing through the feature points of the face (e.g., the eyes and both ends of the mouth) and produces the 3‐D shape of the face. Compared to the conventional method, in the surface model it suffices to specify only a small number of feature points on the facial image. The 3‐D shape of the face can be estimated with sufficient accuracy for image generation, and the expression can be varied in a flexible way. Using this method, if only a single picture or image of a face is available, dynamic images with varying expressions and directions can be generated. An application, for example, is a broadcast program in which a historical figure changes expression or speaks. Another basic application will be to realize the intelligent image coding, which is of recent concern.
Speaker‐independent consonant recognition by integrating discriminant analysis and hmm
Authors: Kawahara Tatsuya , Doshita Shuji , Kitazawa Shigeyoshi
Published: July 2007

A new consonant recognition method is proposed which integrates two stochastic methods: discriminant analysis and HMM. Discriminant analysis is effective in analyzing local patterns but it assumes precise detection of reference points. HMM is able to extract the overall dynamic features and needs no explicit segmentation of speech. However, it lacks the ability to discriminate between similar consonants. The method herein constructs HMM with discriminant analysis front end and recognizes consonants by combining the score obtained by discriminant analysis and that by HMM. For all the Japanese consonants, this integrated method achieved the recognition rate of 92.1 percent, which is higher by 5 to 15 percent than the case using either of the two methods alone.
Automatic identification of human faces by 3‐d shape of surfaces‐using vertices of b‐spline surface
Authors: Abe Toru , Aso Hirotomo , Kimura Masayuki
Published: July 2007

This paper proposes a new method for automatic identification of human faces. This identification method uses a facial three‐dimensional (3‐D) shape that is extracted from an absolute range map. The important issue is to determine what to use as feature vector components for the identification of 3‐D objects. There have been several approaches to identify 3‐D objects, but in the identification of objects that have smooth and complex shape (such as a human face) such approaches did not use the whole feature included in an object, or a long time was required for the identification because of the large number of feature vector components needed.

To solve these problems, an approximation of a facial surface with a B‐spline surface was made by least‐square fitting, and the vertices of the B‐spline surface were used as feature vector components for the identification. Since this process condenses the whole feature included in a surface into a small number of points (vertices), features can be used efficiently for the identification. By this method, identification accuracy of 98.8 percent is obtained for 33 persons (5 data/person).
Method of diagnosing multiple stuck‐at‐faults in combinational circuits
Authors: Yamada Teruhiko , Hamada Shuji , Matsumoto Tatsuo , Takahashi Toshihiko , Nakayama Takao
Published: July 2007

To reduce VLSI turnaround time and cost, an efficient fault diagnosis method must be developed. Electron‐beam probing, which allows observation of the signal values within a chip, is one of the promising approaches for fault diagnosis. However, it is strongly desired that the number of probes be reduced; otherwise, a great deal of effort results.

The electron‐beam probing, guided by deduction based on implications of internal signal values [6], is considered one of the effective solutions to this problem. Here this idea is built upon by adding preprocessing to further reduce the number of probes and postprocessing to improve the diagnosis resolution. The method proposed efficiently diagnoses multiple stuck‐at faults in combinational circuits. Using computational experiments it is also shown that almost all of the faults are diagnosed by probing about 15 percent of the nets when test patterns for detecting single stuck‐at faults are used.
Optimum contrast enhancement using fuzzy sets
Authors: Saito Atsuhisa , Nakajima Masato , Ogawa Koichi
Published: July 2007

The local histogram equalization employed in the contrast enhancement of the image contains two problems: the long processing time and the distortion of the image quality due to the overenhancement.

To reduce the processing time, sampling and hardware implementation are considered. On the other hand, to improve the image quality, the adjustment of the size of the reference region, the weighting in the reference region and clipping are considered.

A problem in past efforts for image quality improvement, however, is that the size of the reference region and the clipping value are set as fixed values, which is one of the reasons that a sufficient improvement of the image quality has not been achieved. It is expected that optimum values exist for the size of the reference region and the clipping for each image and for each part of the image to realize the best contrast.

This paper proposes a method to ameliorate the image distortion by adjusting the size of the reference region and the clipping value by the fuzzy control for each part of the image. The result of processing is shown, and the usefulness of the proposed method is discussed.
Image matching using structures of edge‐image graphs
Authors: Fukunaga Kunio , Asano Takaeshi , Murata Hideto , Izumi Masao
Published: July 2007

This paper proposes an algorithm for examining similarity and correspondence between a pair of images in which the same object appears in different scaling and with rotation such as stereo images or motion stereo images.

As a method for finding correspondence and similarity in an efficient manner, an edge‐line image is found first and then the relationship of connection among edgelines in a graph structure are represented and expressed in an algebraic expression. Using this representation a method is clarified for finding similarity between images and an algorithm is proposed for finding similarity and further correspondence between two images affected by scaling and rotation using the degree of similarity between their line structures. Finally, the algorithm is applied to motion stereo images to examine its effectiveness.
Superquadrics for 3‐D shape indexing language
Authors: Horikoshi Tsutomu , Kasahara Hisashi
Published: July 2007

With the recent development of input, presentation, and processing technologies for three‐dimensional (3‐D) images as the background, the demand for the effective storage and management of 3‐D images is expected to increase. This paper aims at the effective storage and retrieval of the 3‐D images and proposes a 3‐D shape indexing by the superquadrics. The features of super‐quadrics are that the expression is simple and various shapes can be represented using a smaller number of parameters.

To examine the applicability of the function, the technique based on superquadrics is compared with conventional 3‐D modeling from the viewpoint of the power for representing the feature and shape as the technical requirement for the indexing.

The purpose of the conventional modeling technique is to represent the shape from the visual sensation. However, this resulted in a problem whereby it is difficult to determine the shape from the modeled data structure.

By contrast, with superquadrics, the functional parameters are easily related to the shape; thus realizing a sufficient applicability as the indexing. An image retrieval system is constructed using the superquadrics parameters as the indexes, and the usefulness of the proposed indexing technique is demonstrated.
Properties of averaged projection filter for image restoration
Authors: Yamashita Yukihiko , Ogawa Hidemitsu
Published: July 2007

The averaged projection filter (APF) is an optimal restoration filter proposed by the present authors in another paper. Here, properties of the APF are discussed in detail. For example, the image component of the restored image with the APF coincides with the original image if the original image belongs to a subspace. For the original images outside the subspace, the image component becomes the oblique projection onto a subspace of the original image in the mean square sense. A noise suppression mechanism of the APF also is clarified by using the null space of the APF. A simpler expression of the APF is given under some assumption. Finally, relations between the APF and the Wiener filter are discussed.
Evaluation of nonlinear optimization methods for the learning algorithm of artificial neural networks
Authors: Takagi Hideyuki , Sakaue Shigeo , Togawa Hayato
Published: July 2007

This paper describes the implementation of nonlinear optimization methods into the learning of neural networks (NN) and the speed efficiency of four proposed improvements into the backpropagation algorithm. The problems of the backpropagation learning method are pointed out first, and the efficiency of implementing a nonlinear optimization method as a solution to this problems is described.

Two nonlinear optimization methods are selected after inspecting several nonlinear methods from the viewpoint of NN learning to avoid the problem of the backpropagation algorithm. These are the linear search method by Davies, Swann, and Campey (DSC), and the conjugate gradient method by Fletcher and Reeves.

The NN learning algorithms with these standard methods being implemented are formulated. Moreover, the following four improvements of the nonlinear optimization methods are proposed to shorten the NN learning time: (a) fast forward calculation in linear search by consuming a larger amount of memories; (b) avoiding the trap to local minimum point in an early stage of linear search; (c) applying a linear search method suitable for parallel processing; and (d) switching the gradient direction using the conjugate gradient method. The evaluation results have shown that all methods described here are effective in shortening the learning time.
A shape interpolation method for three‐dimensional digital images
Authors: Jin Xiuyi , Yokoi Shigeki , Toriwaki Jun‐Ichiro
Published: July 2007

This paper proposes a new method to form an image of a three‐dimensional (3‐D) object from a set of slice images such as X‐ray CT and MRI by interpolating them. The 3‐D image is reconstructed by using the union of 2‐D images interpolated between adjacent sectional planes which are perpendicular to the slices. The method has features of: (1) interpolations between slices are carried out fully automatically if the image components in a region of interest are overlapped on adjacent slices, and if the region is extracted; (2) the operation of obtaining this is easy since the interpolated shape is obtained in a voxel form; (3) the method can be applied to an object with branches; and (4) the method also can be applied to an object with holes. After reviewing 3‐D interpolation methods, experiments with some artificially made objects and actual MRI images are shown to confirm the usefulness of the proposed method.
Improving image quality for block coding by image division method
Authors: Zheng Zhong , Nakajima Masayuki , Agui Takeshi
Published: July 2007

In block coding, the original image is divided into square blocks composed of N × N pixels, and the coding is applied to each block. When the image is coded at a low bit‐rate, however, there is often produced a block noise in the reconstructed image. When a block noise is produced in the part of the time where the change of the gray‐level is slow, the noise deteriorates the image quality greatly.

To reduce the block noise, this paper proposes three methods of image division. Let the blocks in a horizontal row in the conventional divided image be called a block row. In the first method, the division is executed by moving each block row in the horizontal direction. The amount of translation is determined by a random variable. The second method divides the original image by the rectangular block, and then each block row is moved as in the first method. The third method divides the image using an octagonal block. It is verified by experiment that the block noise can be reduced by the proposed image division.
Development of software system organized by minimal automata realization theorem for gait measuring
Authors: Saito Yoshiyuki , Niinomi Shigeru
Published: July 2007

We describe the software system for improving the efficiency of the gait measuring experiment for the rehabilitation of amputees. This software has the following features: (1) The system consists of independent programs that are connected by a CHAIN statement. So it can easily adjust to the changes or progress in equipment and the measuring method; (2) the flow structure is organized in terms of the algorithm of minimal automata so that redundancy appearing in repeated measurements is eliminated and the load on the amputee is reduced.
Measurement of reaction time in agility using bioelectrical impedance
Authors: Yamamoto Yoshitake , Nakamura Takao , Yamamoto Tatsuma , Tsuji Hiroaki
Published: July 2007

This paper describes a method of reaction time in agility using the bioelectrical impedance, which is not affected by either the measurement items or measurement site that is closer. In this study, the measurement is made for two items, the jumping reaction test and the bar‐gripping reaction test. Reaction time, movement time, and total time are defined based on the waveforms of the lower leg electrical impedance and the forearm electrical impedance. Results are compared to the reaction time and the total time obtained by the traditional method. The results using the proposed method almost agreed with the results of the traditional method, and it is verified that the proposed method can be used to measure the reaction time.

It should be noted that reaction time and movement time can be separated from total time for the bar‐gripping test; this has been impossible in the traditional method. The ability to separate types of time is of use in an experiment in alcohol drinking conditions; results of this experiment are presented. It is expected that the proposed method will be applied to various measurements in such fields as measurement of physical fitness, sport training, and rehabilitation.
Modeling and analyzing advance processing control by extended message‐passing
Authors: Kobayashi Shinya , Nakanishi Hikaru , Tezuka Yoshikazu , Watanabe Takashi
Published: July 2007

The job for which processing is determined only in the course of execution is called the unschedulable job. When an unschedulable job is to be executed in a parallel processing system, it is not predetermined when the communication between processors arises, and synchronization among processors is a serious problem.

This paper considers the mathematical theory for the existence of interprocessor communication and the transmission time in the execution of the unschedulable job. The message‐passing scheme is extended, considering the message transmission probability and the indeterminate aspects of the transmission time. Then the advance processing control is considered, which helps the synchronization among processors in the execution of the unschedulable job, and the overhead is theoretically analyzed. The condition for the task assignment to the processors is derived so that the deterioration of the processing speed due to the overhead can be minimized.
Lowpass filtering method for heart rate variability analysis
Authors: Noguchi Yasuaki , Hataoka Hiroshi , Sugimoto Suguru
Published: July 2007

Various methods have been proposed for the spectral analysis of heart rate variability (HRV). Such methods always require constant period data in time series. However, since the R‐R interval of HRV is, in general, irregular, somehow the experimental data must be converted to constant period data. Assuming an integral pulse frequency modulation (IPFM) model, constant period data can be obtained by passing the heartbeat impulse train through a digital filter using the alias‐free method proposed by French and Holden.

However, the forementioned method has two problems; that is: (1) the frequency characteristics of the lowpass filter are assumed to be ideal, hence the impulse response function of the filter spreads infinitely with respect to time; and (2) only pulses inside the analyzing section are considered while those outside the analyzing section in the convolution integral are ignored.

To solve those problems, the method of French and Holden has been modified in the following three points: (1) such a finite impulse response digital filter was used that the sidelobe of the filter decays rapidly in its impulse response function; (2) the analyzing section as well as its impulse response time were lengthened, thus the pulses outside the analyzing section were considered; and (3) an appropriate window was used.

With these improvements, the truncation error and the computation time could be reduced. Furthermore, as a result of simulation, a much higher accuracy in the demodulation of the heartbeat signal was obtained.
A method for translating natural language program specifications into algebraic specifications
Authors: Seki Hiroyuki , Kasami Tadao , Nabika Eiji , Matsumura Takashi
Published: July 2007

A method for translating program specifications in a natural language into algebraic specifications is presented. The translation rules consist of: (a) syntax rules of the natural language; (b) rules for constructing an intermediate structure similar to “categories” in HPSG; and (c) rules for generating axioms to translate intermediate structures into axioms of the form of logical formula = =True.

Based on the concept of type, which is defined by using the derivations of expressions representing the meanings of natural language sentences in a generative grammar, and based on the characteristics of the functions representing the meanings of words, a more rigorous method of solving the problems of elimination of syntax ambiguities anaphoric bindings, and sorts and scopes of quantifiers is proposed.

Especially, by introducing attributes having the type information of the functions denoted by natural language phrases in the intermediate structures, ambiguities at the time of the parsing can be reduced. Also, the meaning of phrases such as verb phrases can be rigorously defined by using functions having arguments of different types for singular and plural objects. Arguments which are not explicitly specified in natural language sentences can be represented formally by introducing arguments which have types representing the states of the program.

Furthermore, a method is proposed to rigorously deduce the sorts and scopes of the quantifiers by using the dependency relation between the arguments representing the meanings of the words. The results of translating the main part of the OSI session protocol are presented.
3‐D natural interactive interface—using marker tracking from a single view
Authors: Hemmi Kazuo , Inoue Kazuo
Published: July 2007

The proliferation of microcomputers and powerful single‐user minicomputers has created an urgent demand for effective man‐computer interface in three‐dimensional (3‐D) space. This paper presented an interface that is able to recognize finger movement by using an image processing from a single view. Two ring‐shaped markers are attached on the fingertip of an index finger and a thumb. Tracking the positions of two markers, six behaviors of the hand are detected. The detected behaviors to manipulate the object are as follows: catch the object, x translation, y translation, z translation, rotation in the horizontal plane, and rotation in the vertical plane.

The image of the current hand and the object presented by wire‐frame is projected on CRT in real time. The operator is able to manipulate the object moving the hand within the view of the TV camera. Because of the foregoing six motions set equivalent to the motions exactly as done in daily life, an operator can maintain a natural interaction with a computer.