Three dimensional model based coding methods are proposed as next generation image coding methods. These new representations need 3D reconstruction techniques. This paper presents a method that extracts the surfaces of static objects that occlude other objects from a spatiotemporal image captured with straight-line camera motion. We propose the concept of occlusion types and show that the occlusion types are restricted to only eight patterns. Furthermore, we show occlusion type pairs contain information that confirms the existence of surfaces. Occlusion information gives strong cues for segmentation and representation. The method can estimate not only the 3D positions of edge points but also the surfaces bounded by the edge points. We show that combinations of occlusion types contain information that can confirm surface existence. The method was tested successfully on real images by reconstructing flat and curved surfaces. Videos can be hierarchically structured with the method. The method makes various applications possible, such as object selective image communication and object selective video editing.

Signal Transition Graphs (STG'S) [1] are Petrinets [2], which were introduced to represent a behavior of asynchronous circuits. To derive logic functions from an STG, the reachability graph should be constructed. In the verification of STG's some method based on Occurrence nets (OCN) and its prefix, called unfollding, has been proposed [3], [4]. OCN's can represent both causality and concurrency between two nodes by net stryctyre. In this paper, we propose an efficient algorithm to derive a logic function by generating sub-state space of a given STG using the structural properties of OCN. The proposed algorithm can be seem as a parallel algorithm for deriving a logic function.

Winter thundercloud on the coast of the Sea of Japan is difficult for the detection and forecast. This paper reports the new method of thundercloud detection using C-Band weather radar data and meteorological data from rawin sonde. This method includes the thunderclouds echo tracking and chronological evaluation of thundercloud life-cycle stages. The detection probability of critical area for cloud-to-ground lightning is over 90% on winter cloud echo data. This method is workable on realtime processing in work-station computer.

This paper is concerned with bandwidth reservation for circuit groups which handle calls requesting asymmetric forward and backward multi-connections. A model of circuit group with sub-group configuration is treated, and two types of the bandwidth reservation schemes for the model are studied in this paper. One is a global scheme with monitoring the whole circuit group, and the other is a local scheme with monitoring each sub-group independently. The problems of optimizing the reservation parameters are formulated, and optimization methods for the problems are proposed. Numerical example are presented, and effectiveness of the reservation schemes with using the optimized parameters is numerically examined.

One of the important properties of multihop network is the mean internodal distance to evaluate the transmission delay, and the connective semi-random network achieves smaller mean internodal distance than other networks. However, the results are shown only by computer simulation and no theoretical analysis is investigated. Moreover, the network connective probability of the connective semi-random network is relatively small. In this paper, we propose the restricted connective semi-random network whose network connective probability is larger than that of the conventional connective semi-random network. And we theoretically analyze the mean internodal distance and the network connective probability of these two networks. It is shown that if the restriction is loose, the mean internodal distance of our model is almost the same as that of the conventional model, whereas the network connective probability of our model is larger than that of the conventional model. Moreover, the theoretical analyzed results of the mean internodal distance agree well with the simulated results in the conventional model and our model with small restriction.

This paper describes the results obtained of a prototype system, VeriProc/1, based on an algorithm we first presented in [13] which can prove the correctness of pipelined processors automatically without pipeline invariant, human interaction, or additional information. No timing relations such as an abstract function or β-relation is required. The only information required is to specify the location of the selectors in the design. The performance is independent of not only data width but also memory size. Detailed analysis of CPU time is presented. Further, don't-care forcing using additional data easily prepared by the user can improve performance.

In order to produce high quality multimedia contents efficiently, DTPP -desktop program production system- has been proposed. The DTPP is capable of supporting all the necessary procedures of program production, from planning to broadcasting, by molding each process into the desktop environment of program producers. The DTPP system consists of multimedia terminals, a media server, a computing server, and network system. In the DTPP, new technological concepts such as cooperative program production, indexing and utilization of attribute information of images, and video components and spatio-temporal editing will be installed.

The Michelson-interferometer (MI) optical resonator has been applied, together with physical interests, to a low pressure and slow-flow type CO2 laser for specifying the system to a probe laser source. The fundamental characteristics online-selection, oscillation power and transverse mode are also investigated in comparison to the CO2 laser obtained for various resonators such as an open-ended reflective-multiple interferometer (RMI), an open-sided MI, a Fox-Smith interferometer and soon. Consequently, it is confirmedthat the MI type laser proposed can be one of the promising scheme, without losing oscillation power much and transverse mode quality as a probe laser towards lineshape (or laser) parameter analysis. Translating one of the MI mirror by a slight distance on the order of a micron meter along the gain axis, we can not only switch either a single rotational-vibrational line or combination of multiple lines, but also obtain different combination of lines by translating a large amount of the translation distance of the order of 100 µm. Moreover, elimination of one of the side-mirrors in the MI resonator enables us to switch the oscillation lines at the expense of some output power.

A structural active-object system (SAOS) is a transition-based object-oriented system suitable for rapid development of hardware logic simulators. A SAOS consists of a collection of interacting structural active objects (SAOs), whose behaviors are determined by the transition statements provided in their class definitions. Furthermore, SAOs can be structurally and hierarchically composed from their component SAOs like hardware components. These features allow SAOs to model components for circuit simulation more naturally than passive objects used in ordinary object-oriented programming. Also, we can easily create new kinds of components by using the inheritance mechanism. Executions of transition statements may be event-and/or time-driven, and hence digital, analog, and mixed-mode simulation is possible. Prototype simulation programs with graphical user interfaces have been developed as SAOS programs for digital, analog, and mixed-mode circuit simulation.

This paper designs recursive least-squares fixed-point smoother and filter, which use the observed value, the probability that the signal exists, and the covariance information relevant to the signal and observation noises, on the estimation problem associated with the uncertain observations in linear continuous-time systems.

Pitchmatching algorithms are widely used in layout environments where no grid constraints are imposed. However, realistic layouts include multiple grid constraints which facilitate the applications of automatic routing. Hence, pitchmatching algorithms should be extended to those realistic layouts. This paper formulates a pitchmatching problem with multiple grid constraints. An algorithm for solving this problem is constructed as an extension of conventional pitchmatching algorithms. The computational complexity is also discussed in comparison with a conventional naive algorithm. Finally, examples and application results to realistic layouts are presented.

The most troublesome problem in automated X-ray mask inspection is how to exactly determine the threshold level for extracting the pattern portions of each scanning electron microscopic (SEM) image. An exact determination is difficult because the histogram shows, in most cases, a complicated multi-modal pattern and the true threshold level often varies with each successive image. This paper presents a novel thresholding approach for segmenting SEM images of X-ray masks. In this approach, the shape of the histogram of each image is iteratively analyzed until a threshold value minimizing the cost of the correspondence with a reference histogram and satisfying criteria for determining thresholds is obtained. This new approach is used in an automated inspection system. When the input image resolution is set to 0.05µm/pixel, experiments confirm 0.1µm defects are unfailingly detected.

There are some results indicating that a quantum computer seems to be more powerful than ordinary computers. In fact, P.W. Shor showed that a quantum computer can find discrete logarithms and factor integers in polynomial time with bounded error probability. No polynomial time algorithms to find them using ordinary computers are known. In this paper, we show that the cycles in some kinds of periodic functions, e.g., functions proposed as pseudo-random generators, can be found in polynomial time with bounded error probability on a quantum Turing machine. In general, it is known that ordinary computers take exponential time to find the cycles in periodic functions.

A miniature transceiver, including highly integrated MMIC front-end, for 1.9 GHz band personal handy phone system(PHS) has been developed. The terminal, adopting direct conversion transmitter and receiver technology, consists of four high-density RF circuit modules and a digital signal processing LSI with 2.7 V power supply. The four functional modules are a power amplifier, a transmitter,a receiver, and a frequency synthesizer. Each functional module includes one IC chip and passive LCR components connected with solder bumps on module substrate. The experimental miniature PHS handset has been fabricated to verify the design concepts of the miniature transceiver. The total volume of the developed PHS terminal is 60cc, including the 12cc front-end which comprises the four RF functional circuit modules. The air interface connection with the PHS base station simulator has been confirmed.

Through comparing the results of two successive IPTP Character Recognition Competitions which focused on 3-digit handprinted postal codes, we herein analyze the methodologies of the submitted algorithms along with the substituted or rejected patterns of these algorithms. Regarding their methodologies, lesser diversity was apparent specifically concerning the contour-chain code based on local stroke directions and statistical discriminant functions for feature extraction and discrimination. Analysis of the patterns demonstrated that the misrecognized patterns being most often improved were categorized as a decrease in peculiarly shaped handwritten characters or heavy-handed and disconnected strokes. However, most of the remaining misrecognitions were still classed as peculiarly shaped handwriting as commonly shared between the best three algorithms. From these analyses, we could delineate a direction to be taken for developing more effective methodologies and clarify the remaining problems to be overcome by the subsequent intensive research. Furthermore, we evaluate in this article our multi-expert recognition system for achieving higher recognition performances by means of combining complementary recognition algorithms. We performed a subsequent investigation of the Candidate Appearance Likelihood Method using novel experimental conditions and a new examination of the application of the neural network as the combining method for accumulating the broader candidate appearances. The results obtained confirm that combining through the neural network constitutes one of the most effective ways of making the multi-expert recognition system a reality.

This paper consists of two parts. The first part is devoted to comparative study on handwritten ZIP code numeral recognition using seventeen typical feature vectors and seven statistical classifiers. This part is the counterpart of the sister paper Handwritten Postal Code Recognition by Neural Network - A Comparative Study" in this special issue. In the second part, a procedure for feature synthesis from the original feature vectors is studied. In order to reduce the dimensionality of the synthesized feature vector, the effect of the dimension reduction on classification accuracy is examined. The best synthesized feature vector of size 400 achieves remarkably higher recognition accuracy than any of the original feature vectors in recognition experiment using a large number of numeral samples collected from real postal ZIP codes.

This paper describes COCE (COordinative Character Extractor), a method for extracting printed Japanese characters and their character strings from all sorts of document images. COCE is based on a multi-agent system where each agent tries to find a character string and extracts the characters in it. For the adaptability, the agents are allowed to look after arbitrary parts of documents and extract the characters using only the knowledge independent of the layouts. Moreover, the agents check and correct their results sometimes with the help of the other agents. From experimental results, we have verified the effectiveness of our approach.

This letter studies the Peak Cell Rate (PCR) policing of ATM connections that consist of multiple cell flow components. It is shown that the conventional methods proposed for policing the aggregate flow do not use the network's resources efficiently. This letter proposes a simple and efficient UPC (Usage Parameter Control) mechanism based on a tandem leaky bucket for multi-component ATM connections. The results show that network resource requirements can be minimized, with reasonable hardware complexity.

This paper describes advances in the study of handwritten Kanji character recognition mainly performed in Japan. The research focus has shifted from the investigation of the possibility of recognition by the stroke structure analysis method to the study of the feasibility of recognition by the feature matching methods. A great number of features and their extraction methods have been proposed according to this approach. On the other hand, studies on pattern matching methods of recognizing Kanji characters using the character pattern itself have been made. The research efforts based on these two approaches have led to the empirical fact that handwritten Kanji character recognition would become more effective by paying greater attention to the feature of directionality. Furthermore, in an effort to achieve recognition with higher precision, active research work has been carried out on pre-processing techniques, such as the forced reshaping of input pattern, the development of more effective features, and nonlinear flexible matching algorithms. In spite of these efforts, the current character recognition techniques represent only a skill of guessing characters" and are still on an insufficient technical level. Subsequent studies on character recognition must address the question of how to understand characters".

Most conventional methods used in character recognition extract geometrical features, such as stroke direction and connectivity, and compare them with reference patterns in a stored dictionary. Unfortunately, geometrical features are easily degraded by blurs and stains, and by the graphical designs such as used in Japanese newspaper headlines. This noise must be removed before recognition commences, but no preprocessing method is perfectly accurate. This paper proposes a method for recognizing degraded characters as well as characters printed on graphical designs. This method extracts features from binary images, and a new similarity measure, the complementary similarity measure, is used as a discriminant function; it compares the similarity and dissimilarity of binary patterns with reference dictionary patterns. Experiments are conducted using the standard character database ETL-2, which consists of machine-printed Kanji, Hiragana, Katakana, alphanumeric, and special characters. The results show that our method is much more robust against noise than the conventional geometrical-feature method. It also achieves high recognition rates of over 97% for characters with textured foregrounds, over 99% for characters with textured backgrounds, over 98% for outline fonts and over 99% for reverse contrast characters. The experiments for recognizing both the fontstyles and character category show that it also achieves high recognition rates against noise.