We introduce two probabilistic algorithms to determine the motion parameters of a planar shape without knowing a priori the point-to-point correspondences. If the target is limited to rigid objects, an Euclidean transformation can be expressed as a linear equation with six parameters, i.e. two translational parameters and four rotational parameters (the axis of rotation and the rotational speed about the axis). These parameters can be determined by applying the randomized Hough transform. One remarkable feature of our algorithms is that the calculations of the translation and rotation parameters are performed by using points randomly selected from two image frames that are acquired at different times. The estimation of rotation parameters is done using one of two approaches, which we call the triangle search and the polygon search algorithms respectively. Both methods focus on the intersection points of a boundary of the 2D shape and the circles whose centers are located at the shape's centroid and whose radii are generated randomly. The triangle search algorithm randomly selects three different intersection points in each image, such that they form congruent triangles, and then estimates the rotation parameter using these two triangles. However, the polygon search algorithm employs all the intersection points in each image, i.e. all the intersection points in the two image frames form two polygons, and then estimates the rotation parameter with aid of the vertices of these two polygons.

Recently, torque-transmission one-way tip articulated fiberscopes with a working channel have been developed. With this type of scopes, force is transmitted from the operator's hands to the tip of the fiberscope to obtain an adequate field of view. Micro actuators are expected to increasingly replace the operator's hands. Shape memory alloy (SMA) coil spring actuators are well suited to this purpose because of their large displacement compared with conventional actuators. In the fabrication of SMA coil springs, we examined fabrication conditions such as the tension and pitch of the SMA wire. As a result, we have successfully fabricated coil springs with a minimum outer diameter of 76 µm. SMA wire 25 µm in diameter and stainless steel wire 30 µm in diameter were used. As an application using SMA actuators, an active fiberscope (using an image guide fiber with 4200 pixels and light guide fibers) 2 mm in outer diameter with SMA actuators was designed and fabricated. We investigated the mechanical properties of the bending part in designing the SMA actuators. The specifications of the SMA coil springs are determined by the displacement and the force required of the pull wire. The relationship between the displacement of the pull wire and the number of windings of the SMA coil spring was calculated. The effective number of windings of SMA coil spring was found to be seventeen when using wire of 0.3 mm in diameter. The tip of the fiberscope was bent approximately 60 degrees and returned to the straight position when a current was applied to each of the SMA coil springs. A clear picture of the fiberscope which followed the tip bending operation could be received on the monitor. This SMA actuator can be easily extended for bending in many directions by configuring several of these mechanisms.

This paper is concerned with a point-oriented finite volume time domain (FVTD) method in the Cartesian coordinate system for analyzing electromagnetic wave scattering by arbitrary shaped metallic gratings. The perfectly matched layer (PML) is used for the absorbing boundary conditions (ABC's) in the directions corresponding to transmitted and reflected wave regions. An FVTD version of the Floquet's theorm is described to impose the periodic condition in the direction where conducting rods are located periodically. The boundary conditions for a conductor rod which is not well suited to the Cartesian coordinate system are satisfied in an average fashion by introducing image fields at image points. It is shown that the present method gives accurate numerical results. Numerical calculations are also carried out for thick conducting rods which seem difficult to deal with in an analytical way.

This paper is concerned with the perfectly matched layer (PML) for a lossy medium in terms of a finite volume time domain (FVTD) method based only on the Cartesian coordinate system. In this point-oriented FVTD method, there are no spatial differences between electric and magnetic fields. We can take account of the inhomogenity of the lossy medium by considering averaged material constants in each rectangular cell. Numerical examples are given for the electromagnetic wave propagation in two-dimensional tunnels with bends and branches.

This paper is concerned with a point-oriented finite volume time domain (FVTD) method in the Cartesian coordinate system and its application to the analysis of electro-magnetic wave propagation in a bended waveguide as well as radiation from and receiving by a horn antenna with a flange of arbitrary angle. The perfectly matched layer (PML) is used for the absorbing boundary conditions (ABC's). The boundary conditions for a perfect conductor not well suited to the Cartesian coordinate system are also proposed. According to this algorithm, the boundary conditions are satisfied in an average fashion at the conductor surface without changing the computational scheme. In this sense, numerical computations based on the present method are simple but flexible. Numerical results show good convergence.

We propose a novel segmentation algorithm which combines an image segmentation method into small regions with chaotic neurodynamics that has already been clarified to be effective for solving some combinatorial optimization problems. The basic algorithm of an image segmentation is the variable-shape-bloch-segmentation (VB) which searches an opti-mal state of the segmentation by moving the vertices of quadran-gular regions. However, since the algorithm for moving vertices is based upon steepest descent dynamics, this segmentation method has a local minimum problem that the algorithm gets stuck at undesirable local minima. In order to treat such a problem of the VB and improve its performance, we introduce chaotic neurodynamics for optimization. The results of our novel method are compared with those of conventional stochastic dynamics for escaping from undesirable local minima. As a result, the better results are obtained with the chaotic neurodynamical image segmentation.

C1 class smooth interpolation by a fuzzy reasoning for a small data set is proposed. The drafting technique of a human expert is implemented by using a set of fuzzy rules. The effectiveness of the present method is verified by computer simulations and by applications to the practical interpolation problem in a power system.

A new application of the factorization method is reported for 3-D shape reconstruction from endoscope image sequences. The feasibility of the method is verified with some theoretical considerations and results of extensive experiments. This method was developed by Tomasi and Kanade, and improved by Poelman and Kanade, with the aim of achieving accurate shape reconstruction by using a large number of points and images, and robustly applying well-understood matrix computations. However, the latter stage of the method, called normalization, is not as easily understandable as the use of singular value decomposition in the first stage. In fact, as shown in this report, many choices are possible for this normalization and a variety of results have been obtained depending on the choice. This method is easy to understand, easy to implement, and provides sufficient accuracy when the approximation used for the optical system is reasonable. However, the details of the theoretical basis require further study.

There are many instances in which character shape of a class changes smoothly to that of another class. Although there are many ways of the change, the most delicate change is curvature feature. The paper treat this problem systematically in both theoretically and experimentally. Specifically some confusing pairs were constructed which are well known in the field of OCR, such as 2 Z and 4 9. A series of samples generated using each model which change subtly were provided to conduct a psychological experiment. The results exhibit a monotone change of recognition rates from nearly 100% to 0% as the shape changes continuously. To imitate the humans' performance, feature of curvature was extracted based on continuous function representation based on Bezier's spline curve. Specifically two methods were tried from theoretical and engineering points of view and very successful results were obtained.

This letter proposes a new shaping algorithm (CRSA: CDV Reduction Shaping Algorithm) that can freely reduce the maximum CDV value of a cell stream to any predetermined value. There is a trade off between shaping delay and the maximum CDV value reduction achieved when using CRSA. The shaper using CRSA (CR-shaper) output satisfies the Peak Cell Rate Reference Algorithm set with the CR-shaper parameters.

In ITU-T Recommendation I.371, the Generic Cell Rate Algorithm (GCRA) is used to define Peak Cell Rate for the ATM network. It is further applied by the ATM Forum '93 to define Sustainable Cell Rate and Burst Tolerance so as to facilitate Usage Parameter Control and Network Parameter Control. To judge the validity of a cell according to declared GCRA parameters, the enforcer must read the clock time when the cell arrives. However, the clock of the enforcer would roll over frequently and accordingly the judgment would be incorrect. On the other hand, for a shaper in a customer premise node to dispatch cells conforming to the declared GCRA parameters, the clock would also roll over and the cell would not be dispatched correctly. To overcome the problems induced by clock roll-over, based on "time difference" concept, we propose two modified GCRA's for the enforcer and shaper, respectively. According to the proposed algorithms, we design a feasible architecture for a multi-connection shaper and simplify it for an enforcer. They are proven to perform well in spite of the inherent clock roll-over characteristics. By simulation, we evaluate the delay in the shaper and the loss in the enforcer. The features of the architectures are also discussed.

Mathematical morphology is inheriently suitable for range image processing because it can deal with the shape of a function in a natural and intuitive way. In this paper, a new approach to the extraction of the corner-edge-surface structure from 3D range images is proposed. Morphological operations are utilized for segmenting range images into smooth surface regions and high-variation surface regions, where the high-variation surface regions are further segmented into regions of edge type and regions of corner type. A new 3D feature, HV-skeleton, can be extracted for each high-variation surface region. The HV-skeletons can be thought of as the skeletons of high-variation surface regions and are useful for feature matching. The 3D features extracted by our approach are invariant to 3D translations and rotations, and can be utilized for higher-level vision tasks such as registration and recognition. Experimental results show that the new 3D feature extraction method works well for both simple geometric objects and complex shaped objects such as human faces.

Recently, some speech recognition methods using fusion of visual and auditory information have been researched. In this paper, a study on the mouth shape image suitable for fusion of visual and auditory information has been described. Features of mouth shape which are extracted from gray level image and binary image are adopted, and speech recognition using linear combination method has been performed. From results of speech recognition, the studies on the mouth shape features which are effective in fusion of visual and auditory information have been performed. And the effectiveness of using two kinds of mouth shape features also has been confirmed.

A new three-dimensional MMIC structure and an ultra-wideband miniature MMIC balun are proposed. The MMIC is a combined structure of multilayer MMICs and U-shaped micro-wires. This technology effectively reduces chip size and enhances MMIC performance. The proposed balun is constructed with three narrow conductors located side by side. The U-shaped micro-wire technology is employed to reduce the insertion loss and chip size. 1.51 dB insertion loss over 10 to 30 GHz, and 2 dB and 5 degrees of amplitude and phase balances over 5 to 35 GHz have been obtained. The intrinsic area of the balun is only 450800 µm, about 1/5 to 1/3 the area of recently reported miniaturized MMIC baluns.

A computer-based system for the automatic determination of the physical parameters of rainfall was developed. The measuring device consists of a light source and two TV cameras. Images of raindrops that fell through the slit were observed on a frosted glass plate as shadow images which were photographed simultaneously by two TV cameras with different shutter speeds and analyzed. The data indicated that the shape of raindrops were spheroid in case of small diameter but were slightly deformed into an oblate spheroid in case of larger diameter, and the fall velocity tends to increase with increasing size of raindrops. Rainfall rates calculated from the shape and velocity were compared with those measured directly and found to agree.

We propose a new compaction problem that allows layout elements to have many shape possibilities. The objective of the problem is to find not only positions but also shapes of layout elements. We present an efficient method to solve the problem--compaction with shape optimization. This method simplifies the problem by considering the optimization of shapes only for the layout elements on a critical path. The layout is compacted step by step while optimizing the shapes of layout elements. Another importance of this compaction technique is that it makes layout to be "recyclable" for other set of device parameters. The experimental examples, which attempt shape optimization and recycle of analog layout, confirms the importance and efficiency of our method.

Based on a newly proposed notion of relational network, a novel learning mechanism for model acquisition is developed. This new mechanism explicitly deals with both qualitative and quantitative relations between parts of an object. Qualitative relations are mirrored in the topology of the network. Quantitative relations appear in the form of generalized predicates, that is, predicates that are graded in their validity over a certain range. Starting from a decomposition of binary objects into meaningful parts, first a description of the decomposition in terms of relational networks is obtained. Based on the description of two or more instances of the same concept, generalizations are obtained by first finding matchings between instances. Generalizing itself proceeds on two levels: the topological and the predicate level. Topological generalization is achieved by a simple rule-based graph generalizer. Generalization of the predicates uses some ideas from MYCIN. After successful generalization, the system attempts to derive a simple and coarse description of the achieved result in terms of near natural language. Several examples underline the validity of relational networks and illustrate the performance of the proposed system.

In this paper, we extend two-image photometric stereo method to treat a concave polyhedron, and present an iterative algorithm to remove the influence of interreflections. By the method we can obtain the shape and reflectance of a concave polyhedron with perfectly diffuse (Lambertian) and unknown constant reflectance. Both simulation and experiment show the feasibility and accuracy of the method.

This paper describes a new method to determine the 3-D position coordinates of a Lambertian surface from four shaded images acquired with an actively controlled, nearby moving point light source. The method treats both the case when the initial position of the light source is known and the case when it is unknown.

A Direct Radiating Array Antenna (DRAA) concept has been introduced to international satellite communications in order to achieve multiple shaped beams which are electrically reconfigurable. The subject of this paper is to describe the new design method for a reconfigurable DRAA. The design procedure consists of three steps, 1) derivation of the initial array layout using Fourier transform method (FTM) , 2) array shape rearrangement, 3) optimization of the final array excitation with the modified constraint least mean square (MCLMS) algorithm. At the first step, it is necessary to derive the initial array layout for the desired shaped beam with respect to array shape, number of antenna elements, and excitation distribution. For this purpose, a new closed form solution of FTM using N-polygonal desired coverage is used. At the second step, the array shape is rearranged to fit the beam forming network (BFN) configuration which can reduce insertion loss and influence on frequency variation sensitivity. At the third step, the array excitation is optimized using MCLMS which is exploited to satisfy the power sum constraints caused by the restriction of the BFN configuration. The design method provides useful insight regarding the layout design of a DRAA with well-shaped coverages, the low insertion loss of the BFN and the high sidelobe isolation characteristic. The design of the reconfigurable DRAA with the specified multiple shaped (beams is demonstrated and compared with the experimental model.