A representation scheme is presented for shapes of three-dimensional curved objects whose surface curvatures are not continuous at all points, i.e., surfaces with C1 continuity only. The representation consists of a subset of lines of curvature and their intersections, called surface structure descriptors, organized in a three-layer hierarchy of increasing stringency. From these descriptors, a hierarchical parameterization of C1 surfaces leading to a global shape representation of the object is obtained in terms of enclosing boundaries of bumps and dents, ridge and valley lines, and peaks and pits (curvature extreme points). To handle the discontinuities of surface curvatures, we introduce a computational scheme in which gradient directions of surface curvatures at the discontinuities can be inferred. Simulation results on the computation of these descriptors from curved surfaces are shown. Potential applications of this representation scheme in computer vision tasks are discussed.

Programmable Logic Arrays (PLAs) are very suitable to VLSI implementation and very convenient for logic design, because of the structure regularity and programmable flexibility. However, PLAs are random-resistant circuits for which random patterns are not effective for achieving a high fault coverage, because of their high fan-in and fan-out. This paper presents an O (mn) test generation algorithm to generate ETG (Easy Test Generation) patterns wher m is the number of input lines and n is the number of products. The fault coverage of ETG patterns can be calcuated based on parameters of a given PLA. Experimental results show that the fault coverage is higher than 90% with the confident 90.3%. An alternative of the O (mn) test generation algorithm to enhance fault coverage is presented. The given PLA is also possivel to be modified to an ETG PLA to reach 100% fault coverage of ETG patterns.

The one-dimensional map represented by the Bernoulli shift is a candidate of true random number generators. However, no computer with finite-word-length can precisely realize the Bernoulli shift. The M-sequence is shown to be one of finite-word-length approximations to the Bernoulli shift in the sense that the many-to-many map generated by M-sequence is the same as the finite-word-length realization of the iterated Bernoulli shift.

FITH2 algorithm defined by the equations ρ=xcosθysinθ(π/(2K)). xsinθ at 0θπ/2 and ρ=xcosθysinθ(π/(2K))ycosθ at π/2θπ is a Hough transform which requires nothing of the trigonometric and functional operations to generate the Hough distributions. It is demonstrated in ths paper that the FIHT2 is a complete alternative of the usual Hough transform (HT) defined by ρ=xcosθysinθin the sense that the both tranforms could work perfectly as a line detector. It is easy to show that the Hough curves of the FIHT2 can be generated in an incremental way where only addition operations are needed. It is also investigated that the difference between HT and FIHT2 could be estimated to be neglected.

In this paper, we propose a surface-based reconstruction technique which simplifies the process of scene reconstruction and increase reliability. Integrationg grid coding and intensity image analysis methods, discontinuities are classified and stable surfaces which make up the skeleton structure of a room (i.e., wall, ceiling, floor, etc.) are extracted. Local models are then reconstructed under the planar assumption, and merged into the global model. The experimental results show that local errors do not radically alter the adjacency relationships of detected surfaces, so robust reconstruction can be achieved.

This paper describes the improvement of the prior personal computer based karyotyping system of Giemsastained chromosomes that had resolution of 256256 pixels. To upgrade the accuracy of karyotyping the resolution of the image acquisition board was increased to 512512 pixels and the algorithm of finding the centromere of a chromosome was improved. The results of the karyotyping using this improved system with an image of chromosomes taken from the Rana Amurensis had been better than the previous one.

The Fourier transform grid methos (FTGM) had been proposed previously by the authors for measuring in-plane strain distibution. In this paper, two automated grid methods are proposed using the FTGM. One is a method for measuring the shape of the full surface of a cylindrical object. A new forming grid method is proposed for introducing the FTGM into the slit projection method. In order to measure the full surface of the object, the object is rotated by a constant angle, the projected line is recorded and the line image is shifted by a constant number of pixels. The next recorded projected line is superimposed in the same image memory. By repeating the above operation, a grating image is formed in the image memory. The formed grating iemage is precisely analyzed at once by the FTGM. The other is a shape and strain measurement method for a curved plate. In the conventional automated grid method, because the position of a grid point is exprssed by an integer number of pixels, it is difficult to use for accurate measurement. Using the FTGM, the position of the grating is measured by the decimal number of pixels by analyzing the phase distribution. The accuracy is higher. Moreover, since each pixel point has a phase, matching for corresponding points between different images is easily performed by comparing the phases of the points. Two applications for medical and mechanical experiments are presented.

The measuring and display system for a merathon TV program employing a realtime image processor and a fast graphic processor has been developed. The system consists of two parts, the step frequency subsystem and the Computer Graphic display subsystem. In the first subsystem, the step frequency for a marathon runner is detected from the image signal by tracking the motion of the runner's face. In the second subsystem, the data for the position of each joint in the runner's leg are prepared beforehand. By applying the step frequency to those prepared data, the runner's motion is drawn out as an animation.

In many parallel processing systems, interference among jobs, which comes from resource contention, causes performance degradation. In order to solve the problem of resource contention, an important question is: "How shall we optimize jop scheduling policy?" However, the traditional queuing theory assuming a first-come-first-served policy is not suitable for analyzing scheduling policy. A new method called Stochastic Petri Nets (SPN) is suitable for analyzing scheduling policy, because with it job arrival states, resource assignment states, and job flow due to these states can be modeled. However, the describing powers of places and transitions, elements of SPN, are as weak as Assembler in program languages. If we model scheduling logic in detail with SPN, that model becomes huge with a great number of places and transitions. Not only modeling of scheduling logic itself becomes difficult, but also analyzing of the model becomes difficult. In this paper, we consider a system in which resource contention causes job interference, and propose a method of analyzing scheduling policy for interference avoidance. In this method, for each scheduling policy, we introduce functions between job execution performance and system states. By incorporating this function into a SPN model, we cut down the size of the model. We apply the proposed method to analyzing performance of the control policy of a magnetic tape library, and show the efficiency and limit of this method.

A new system for high speed and continuous 3-D measurement is presented. It is based on slit-ray projection method. Remarkable features of our system--high speed and continuous measurement--mainly come from its image plane constructed by PSD array which is horizontally non-divided and linear, whereas vertically divided in numbers. Each row PSD element is attached to respective analog signal processor, A/D converter and memory element. By the virtue of this configuration of the image plane, we can store the positional information of slit-like image on the image plane into memory elements in real time, without waiting for one frame interval as is required in the conventional methods with scanning type image grabbers. As the result, we can scan the slit-ray at a constant high angular velocity and calculate the deflection angle of the slit-ray from scanning time of it, which is set on the address bus of memory elements in our system. Thus, basic datum for 3-D measurement are acquired during only one scanning of slit-ray at high speed in the form of addresses of memory elements and datum stored in them. Moreover, if we use large capacity and/or dual port memories, we may continuously obtain 3-D datum of as many scenes as we want. Trial system has verified our method showing data acquisition time per scene within a few milliseconds and enabling us to obtain 3-D datum continuously at a rate of hundreds scenes per second.

The user interface part of an application program can be easily and compactly constructed by combining the parallel execution primitive Linda and the state transition description language Flex with a general purpose programming language. With this approach, a wide range of interfaces can be constructed without using languages or systems specific to user interface design. Using these tools, parallel execution, separation/communication between the application and the interface part, and complicated dialogs can easily be specified. In our implementation, the specification is compiled into C and runs efficiently without any runtime system.

In this paper, the general Petri net liveness problem is discussed. First, a useful necessary condition and a simple sufficient condition for liveness of general Petri nets without time are derived by using only the concept of the deadlocks. Next, it is discussed that the strong motivations, to rebuild the expanded definitions of deadlocks and traps, and to clarify their structural properties and the mutual relationships between deadlocks and traps, result from the main theorems of this paper. It is also shown that the theorems derived in this paper are applied to some timed Petri nets because some timed Petri nets are equivalently transformed into general Petri nets without time by the proposed transformation rule, remaining the basic structural properties such as boundedness, liveness, and reachability of those timed Petri nets unchanged.

Translation of the scalable outline font data as represented by a set of control points of the cubic Bezier curve, etc. into the bitmap data for desk-top publishing (DTP) applications requires a significant amount of computation. In this paper, we propose a special purpose chip called KAFOG for the high-speed generation of bitmap font from the Hangul PostScript file for screen display as well as LBP (Laser Beam Printer) output. KAFOG chip was implemented in 1.5 µm CMOS gate array using 17 K gates. The computation throughput of the KAFOG chip is 250 K cubic Bezier curve segments (each curve segment is composed of four control points) per second at the clock frequency of 40 MHz.

A wide beamwidth and broad bandwidth microstrip antenna is presented. It consists of a rectangular patch antenna and a pair of parasitic short circuit patches placed over the radiating edges of the rectangular patch. The parasitic element not only widens the bandwidth of the antenna but also forms a narrowed pair of radiating edges, so the E-plane beamwidth becomes broader. An antenna trial model achieved a bandwidth of 16% (VSWR1.5) and a broad E-plane beamwidth of 165 degrees.

This paper proposes an analysis method of a priority scheme for mixed Continuous-Bit-Rate (CBR) and burst traffic contending based on Asynchronous Transfer Mode (ATM) which applied the future B-ISDN. The method is analyzed througn two separated source models; binary source model for burst traffic and random source model for CBR traffic. First we defines arrival process using the two source models according to traffic characteristics so that in adaptation to queueing modeling the system is analyzed through M/G/1/N. Next in view point of service process three priority schemes: push-out scheme, partial buffer sharing and separate route for each traffic loss are proposed. Here we impose two different priority classes on each source model. With the use of superposition of traffic from a number of independent random sources and binary sources, the partial buffer sharing scheme is proved to be best in three priority schemes for addmissible load and cell loss probability. In this paper, we propose partial buffer sharing scheme with priority scheme for two different traffics.

In maritime satellite communications particularly for low G/T earth stations, multipath fading becomes a serious problem, especially at low elevation angles. In this paper, we show a new fading reduction scheme for sea surface reflection applicable to INMARSAT-C system. This method using open-loop-controlled diversity combined with an FEC and a interleaver overcomes the disadvantages generally associated with a conventional diversity system. This method has a respectable fading reduction effect, moreover, it can shorten the interleave length. We evaluate these effects of the system by a computer simulation and discuss its performance. The applicability of this fading reduction technique is not only to the INMARSAT-C but also to any kind of digital communication systems where interleave, FEC, and diversity can be used.

This paper describes the evaluation results for Group 3 (G3) facsimile transmission in the transparent mode over the digital cellular system. Effectiveness of a convolutional code is clarified for encoding the G3 facsimile data from analysis of error correction capability for the transparent mode. The 1/2 convolutional code is used as the error correction code in the digital cellular circuit, and a simulation experiment is conducted at the data transmission speed of 4,800 bit/sec in a G3 facsimile. It has been clarified that the transparent transmission system is applicable up to a fading frequency of 80 Hz, a received power of 100 dBm and a handoff occupancy frequency of 4 times per minute on asumption of handoff occurrence probability in a Poisson distribution. This scheme presents the high reliable G3 facsimile transmission which does not depend on delay time of the digital cellular system.

This study proposes fuzzy matrix quantization (FMQ) which is a new coding technique developed to obtain discrete symbols employed for hidden Markov models (HMM's). FMQ is a coding technique combining fuzzy vector quantization with matrix quantization. The validity of FMQ is evaluated by a speaker-independent isolated word recognition task. First, the effect of FMQ is examined when FMQ is applied to the training phase and/or recognition phase. The effects of number of training data, codebook size and codeword matrix size for recognition accuracy are investigated. And the results of the speech recognition based on HMM recognizer using FMQ technique is compared with HMM recognizers using conventional quantization methods, vector quantization and fuzzy vector quantization. As a result, FMQ is the effective coding technique for isolated word recognition on condition that codebook size is large, above all, when FMQ is applied to the training phase and training data set is small.

The stability and output power of the fundamental transverse mode in a surface emitting laser has been studied by simulation. We have employed a 3-dimensional beam propagation method considering refractive index and gain changes due to carrier variations in an active medium by solving a diffusion equation. From this simulation, the higher order mode suppression ratio can be as large as 35 dB for injection levels higher than 1.5 times the threshold, and out of more than 10 mW can be expected when the diameter of one side mirror is about 5 µm and the active layer thickness d=0.5-1.0 µm.

This paper deals with electromagnetic wave scattering by an infinite plane metallic double grating with three dielectric layers in case of E- and H-waves excitations. The field expressions for this problem are obtained by making use of superposition of the results of the single grating case. The analytical method used here is based on the spectral domain method combined with the sampling theorem. Some numerical results are presented for the near fields such as the surface current distributions on the strips and for the far fields such as the frequency characteristics as well as the insertion loss from the viewpoint of a polarization discriminator.