In this paper a method of recognizing waveform based on the Discrete Wavelet Transform (DWT) presented by us is applied to detecting the K-complex in human's EEG which is a slow wave overridden by fast rhythms (called as spindle). The features of K-complex are extracted in terms of three parameters: the local maxima of the wavelet transform modulus, average slope and the number of DWT coefficients in a wave. The 4th order B-spline wavelet is selected as the wavelet basis. Two channels at different resolutions are used to detect slow wave and sleep spindle contained in the K-complex. According to the principle of the minimum distance classification the classifiers are designed in order to decide the thresholds of recognition criteria. The EEG signal containing K-complexes elicited by sound stimuli is used as pattern to train the classifiers. Compared with traditional method of waveform recognition in time domain, this method has the advantage of automatically classifying duration ranks of various waves with different frequencies. Hence, it specially is suitable to recognition of signals which are the superimposition of waves with different frequencies. The experimental results of detection of K-complexes indicate that the method is effective.

In formal specification languages for parallel processes, such as CSP and LOTOS, algebraic laws for basic operators are provided that can be used to transform process expressions, and in particular, composition of processes can be calculated using these laws. Process composition can be used to simplify and improve the specification, and also to prove properties of the specification such as deadlock absence. We here test the practicality of process composition using CSP and suggest useful techniques, working in an example with nontrivial size and complexity. We emphasize that the size explosion of composed processes, caused by interleaving of the events of component processes, is a serious problem. Then we propose a technique, which we name two-way pipe, that can be used to reduce the size of the composed process, regarded as a program optimization at specification level.

This paper describes a method of coding image sequences based on global/local motion information. The suggested method initially estimates global motion parameters and segments a target region from a given image. Then we coded background and target region by assigning more bits to the target region and less bits to background in order to reconstruct the target region with high quality. Simulations show that the suggested algorithm has better result than the existing methods, especially in the circumstances where background changes and target region is small enough compared with that of background.

In this paper, we propose a new class of ID-based non-interactive key sharing scheme with a trusted center which generate a common key on the basis of a linear combination of the center secrets. We also discuss the security of the proposed schemes, and show that the proposed schemes prevent the conventional collusion attack, by adding another random integers unique to each user, on the secret vector that is assigned to the user. Furthermore, we present a new type of a statistical collusion attack which is more suitable for the proposed schemes. We also present the lower bound of the threshold of the statistical collusion attack on the proposed schemes. The proposed schemes can be easily implemented compared with other schemes as they require only computing of the inner product of two vectors over finite ring (including finite field) and an Euclidean quotient, for generating the common key. Our proposed schemes can be regarded as modified versions of the Blom's original scheme. However our proposed schemes are secure against our new type of the attack, as well as the collusion attack based on the solving of the linear equations, although Blom's scheme is insecure against both of these collusion attacks.

This paper proposes the concept of Tool-Based Direct Deformation Method (TB-DDM) which supports networked CAD (Computer Aided Design) systems with virtual reality technologies. TB-DDM allows designers to sculpt free forms directly with tools; each tool has its deforming characteristics, such as, the area and the shape of deformation. TB-DDM's direct deformation interface is independent of form representations because the system automatically calculates appropriate deformation according to its form representation when a tool pushes" a form. The deformation with TB-DDM is concisely described by the initial shape, types of tools, and thier loci; the description enables cooperative CAD systems with narrow bandwidth network to share design process rapidly and to distribute computational load.

This paper presents an alternative traffic model for an ATM multiplexer providing video, voice, image, and data services. The traffic model classifies the input traffic into two types: real-time and non-real-time. The input process for realtime traffic is periodic and correlated, while that for non-realtime traffic is batch Poisson and independent. This multiplexer is assumed to be a priority queueing system with synchronous servers operating on time-frame basis and with separate finite buffers for each type of traffic. State probabilities and performance measures are successfully obtained using a Markov analysis technique and an application of the residue theorem in complex variable. The results can be applied in the design of an ATM multiplexer.

The Hyper Hospital" is a novel medical care system which will be constructed on an electronic information network. The human interface of the Hyper Hospital based on the modern virtual reality technology is expected to enhance patients' ability to heal by providing computer-supported on-line visual consultations. In order to investigate the effects and features of on-line visual consultations in the Hyper Hospital, we conducted an experiment to clarify the influence of electronic interviews on the talking behavior of interviewees in the context of simulated doctor-patient interactions. Four types of distant-confrontation interviews were made with voluntary subjects and their verbal and non-verbal responses were analyzed from the behavioral point of view. The types of interviews included three types of electronic media-mediated interviews and one of a live face to face interview. There was a tendency in the media-mediated interviews that both the latency and the duration of interviewees' utterances in answering questions increased when they were compared with those of live face to face interviews. These results suggest that the interviewee became more verbose or talkative in the media-mediated interviews than in the live interviews. However, the interviewee's psychological tension was generally augmented in the media-mediated interviews, which was suggested by the delay of the initiation of conversations as compared to the conventional face-to-face interviews. We also discuss the applicability of media-mediated interviews by an electronic doctor which we are studying as a functional unit of our Hyper Hospital, a network based virtual reality space for medical care.

This paper presents a new sort of multilayer piezoelectric ceramic transformer for switching regulated power supplies. This piezoelectric transformer operates in the second thickness extensional vibration mode. Its resonant frequency is higher than 1 MHz. First, numerical simulation was implemented using a distributed constant electromechanical equivalent circuit method. It was calculated that this piezoelectric transformer, which has higher than 200 mechanical quality factor Qm, could work with higher than 90% efficiency and in more than 20-W/cm3 high power density. Second, a trially fabricated transformer, which is 15 mm long, 15 mm wide and 2.2 mm thick, was examined. Modified PbTiO3 family ceramics were used for the piezoelectric transformer material, because of the large anisotropy between electromechanical coupling factors kt and kp. Obtained results indicate that the piezoelectric transformer has good resonant characteristics, with little spurious vibration, and exhibits 16-W/cm3 power density with high efficiency at 2 MHz. Moreover, a switching regulated power supply, applying the piezoelectric ceramic transformer, was built and examined.

We propose an optimal throughput problem using graph transformations to maximize throughput of a pipelined data path with some loops. The upper bound of the throughput, equals to the lower bound of the iteration interval between the start of two successive iterations, is limited by the length of a critical loop. Therefore we can maximize the throughput by minimizing the length of the critical loop. The proposed method first schedules an initial Data Flow Graph (DFG) under the initial iteration interval as few as it can use resources, then it transforms the DFG into the flow graph with the minimal length of the critical loop by rescheduling the given initial scheduling result. If there are any control steps which violate the resource constraints owing to the transformations, then these operations are adjusted so as to satisfy given resource consrtraints. Finally by rescheduling the transformed DFG, it gives a schedule with maximum throughput. Experiments show the efficiency of our proposed approach.

On ranging system on short distance using spread spectrum, we examine waveform responses to predict the state of electromagnetic waveform propagation while the signal is received after scattered by a target. Then this system and the numerical results are discussed.

A new algorithm, which is incorporated into the waveform relaxation analysis, for efficiently simulating the transient response of single lossy transmission lines or lossy coupled multiconductor transmission lines, terminated with arbitrary networks will be presented. This method exploits the inherent delay present in a transmission line for achieving simulation efficiency equivalent to obtaining converged waveforms with a single iteration by the conventional iterative waveform relaxation approach. To this end we propose 'line delay window partitioning' algorithm in which the simulation interval is divided into sequential windows of duration equal to the transmission line delay. This window scheme enables the computation of the reflected voltage waveforms accurately, ahead of simulation, in each window. It should be noted that the present window partitioning scheme is different from the existing window techniques which are aimed at exploiting the non–uniform convergence in different windows. In contrast, the present window technique is equivalent to achieving uniform convergence in all the windows with a single iteration. In addition our method eliminates the need to simulate the transmission line delay by the application of Branin's classical method of characteristics. Further, we describe a simple and efficient method to compute the attenuated waveforms using a particular form of lumped element model of attenuation function. Simulation examples of both single and coupled lines terminated with linear and nonlinear elements will be presented. Comparison indicates that the present method is several times faster than the previous waveform relaxation method and its accuracy is verified by the circuit simulator PSpice.

In this paper, we present an approach which is applicable to both the stereo and the motion correspondence problems. We take into account different representations of edge primitives and introduce the idea of Hough Transform to develop a matching algorithm which does not require any local constraints during the matching process.

We are developing GENESIS, a new seamless total environment for designing, developing, installing, and operating various types of telecommunication networks as extremely large distributed processing applications in the future network integrated by ATM. Similar uniform architectures for quick introduction and easy management of service or operation applications have been proposed, such as by TINA, but there has been insufficient study on how to operate and con figure those applications. This paper discusses the implementation model and execution environment in GENESIS from the viewpoint of flexible operation according to network conditions. The implementation model can describe detailed configurations under various conditions on design or operation, independently of the execution environment. To achieve the goals of GENESIS, our execution environment provides message handling functions and a transparent interface for controlling network resources independently of the configuration, and dynamic reconfiguration functions that are independent of the execution. This paper also reports the prototype system GENESIS-1. The GENESIS-1 message handling mechanism and the effect of the reconfiguration functions are described.

In this letter we present an electronic circuit based on a neural net to compute the discrete Walsh transform. We show both analytically and by simulation that the circuit is guaranteed to settle into the correct values.

Numerical studies of reaction–diffusion systems which consist of chaotic oscillators are carried out. The Rössler oscillators are used, which are arranged two–dimensionally and coupled by diffusion. Pacemakers where the average periods of the oscillators are artificially changed are set to produce target patterns. It is found that target patterns emerge from pacemakers and grow up as if they were in a regular oscillatory medium. The wavelength of the pattern can be varied and controlled by changing the parameters (size and frequency) of the pacemaker. The behavior of the coupled system depends on the size of the system and the strength of the pacemaker. When the system size is large, the Poincar return maps show that the behavior of the coupled system is not simple and the orbit falls into a high–dimensional attractor, while for a small system the attractor is rather simple and a one–dimensional map is obtained. Moreover, for appropriate strength of pacemakers and for certain sizes of the systems the oscillations become periodic. It is also found that the largest and local Lyapunov exponents of the system are positive and these values are uniformly distributed over the pattern. The values of the exponents are smaller than that of the uncoupled Rössler oscillator; this is due to the fact that the diffusion reduces the exponents and modifies the form of the attractor. We conclude that the large scale patterns can stably exist in the chaotic medium.

In this paper we propose a formal linearization method which permits us to transform nonlinear systems into linear systems by means of the Chebyshev interpolation. Nonlinear systems are usually represented by nonlinear differential equations. We introduce a linearizing function that consists of a sequence of the Chebyshev polynomials. The nonlinear equations are approximated by the method of Chebyshev interpolation and linearized with respect to the linearizing function. The excellent characteristics of this method are as follows: high accuracy of the approximation, convenient design, simple operation, easy usage of computer, etc. The coefficients of the resulting linear system are obtained by recurrence formula. The paper also have error bounds of this linearization which show that the accuracy of the approximation by the linearization increases as the order of the Chebyshev polynomials increases. A nonlinear filter is synthesized as an application of this method. Numerical computer experiments show that the proposed method is able to linearize a given nonlinear system properly.

By applying Wigner distribution, which has high time resolution and high random noise reducing capability, to the acoustic bio–signals, the possibility of early diagnosis in both intracranial vascular deformation and prosthetic cardiac valve malfunction increased. Especially in latter case, 1st–order local moment of the distribution showed its effectiveness.

The warp model of the extended Hough transform (EHT) has been proposed to design the explicit expression of the transform function of EHT. The warp model is a skewed parameter space (R(µ,ξ), φ(µ,ξ)) of the space (µ,ξ), which is homeomorphic to the original (ρ,θ) parameter space. We note that the introduction of the skewness of the parameter space defines the angular and positional sensitivity characteristics required in the detection of lines from the pattern space. With the intent of contributing some solutions to basic computer vision problems, we present theoretically a dynamic and centralfine/peripheral-coarse camera vision architecture by means of this warp model of Hough transform. We call this camera vision architecture askant vision' from an analogy to the human askant glance. In this paper, an outline of the EHT is briefly shown by giving three functional conditions to ensure the homeomorphic relation between (µ,ξ) and (ρ,θ) parameter spaces. After an interpretation of the warp model is presented, a procedure to provide the transform function and a central-coarse/peripheralfine Hough transform function are introduced. Then in order to realize a dynamic control mechanism, it is proposed that shifting of the origin of the pattern space leads to sinusoidal modification of the Hough parameter space.

The access control method adopted by UNIX is simple, understandable, and useful. However, it is quite possible that unexpected information flows occur when we are cooperating with some group members on UNIX. Introducing notions such as "flow right," "maximal permission" and "minimal umask value", this note proposes a simple method, can be seen as a natural extension of UNIX, to control indirect information flows without losing availability and understandability of UNIX.

Recognizable series is a model of a sequential machine. A recognizable series S is represented by a triple (λ,µ,γ), called a linear representation of S, where λ is a row vector of dimension n specifying the initial state, γ is a column vector of dimension n specifying the output at a state, and µ is a morphism from input words to nn matrices specifying the state transition. The output for an input word w is defined as λ(µw) γ, called the coefficient of w in S, and written as (S,w). We present an algorithm which constructs a reduced linear representation of an unknown recognizable series S, with coefficients in a commutative field, using coefficient queries and equivalence queries. The answer to a coefficient query, with a word w, is the coefficient (S, w) of w in S. When one asks an equivalence query with a linear representation (λ,µ,γ), if (λ,µ,γ) is a linear representation of S, yes is returned, and otherwise a word c such that λ (µc) γ(S, c) and the coefficient (S, c) are returned: Such a word c is called a counterexample for the query. For each execution step of the algorithm, the execution time consumed from the initial step to the current step is O(mN 4M), where N is the dimension of a reduced linear representation of S, M is the maximum time consumed by a single fundamental operation (addition, subtraction, multiplication or division), and m is the maximum length of counterexamples as answers to equivalence queries returned until that step.