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.

A timing-driven global routing algorithm is proposed that directly models the path-based timing constraints. By keeping track of the critical path delay and channel densities, and using novel heuristic criteria, it can select routing paths that minimize area as well as satisfy the timing constraints. Using bipolar-specific features, this router can be used to design LSI chips that handle signals with speeds greater that a gigabit per second. Experimental results shows an average delay improvement of 17.6%.

The validity of numerical design scheme of CP-PASS (Circularly Polarized Printed Array antenna composed of Strips and Slots) is considered. The strip element of CP-PASS is composed of a strip dipole and a window which increases the frequency bandwidth of the strip element. With the window, however, analysis of the antenna becomes difficult if a simple analytical model is used. The previous design procedure requierd an experimental procedure. By using modern computers, the FDTD (finite-difference time-domain) method becomes powerful tool for the analysis of 3D-structured antennas. In this paper, numerical results of the FDTD analysis for CP-PASS is compared with results from experiments. The characteristics of the unit-radiator of CP-PASS are demonstrated numerically. This paper shows that CP-PASS can be designed numerically and a new path has opened in the study of CP-PASS.

This paper presents an analysis of the control characteristics of the series resonant converter with a parallel resonant circuit, especially under parallel resonant frequency. Operations of the circuit are classified into several modes. The control characteristics are calculated using the equations derived from equivalent circuits, and are verified by the experiments. From the analysis, the mechanism of a jumping phenomenon in the closed-loop control characteristics is clarified.

The many-user networked virtual world system InterSpace" is described. This system's main purpose is to enhance the user's communication activities. In InterSpace, the real world information is embedded in the shared virtual world as a combination of video and CG images. Users can ovserve and access this information by simply looking and approaching embedded images. The concept of InterSpace and a prototype system of this service are introduced.

Throughout the paper, the nearest-neighbour (NN) interconnection of switches within a multistage interconnection network (MIN) is analysed. Three main results are obtained: (1) The switch preserving transformation of a 2-D MIN into the 1-D MIN (and vice versa) (2) The rearrangeability of the MIN and (3) The number of stages (NS) for the rearrangeable nonblocking interconnection. The analysis is extended to any dimension of the interconnected data set. The topological equivalence between 1-D MINs with NN interconnections (NN-MINs) and 1-D cellular arrays is shown.

In a hybrid coder which employs motion compensation and discrete cosine transform (MC-DCT coder), up to 90% of bits are used to represent the quantized DCT blocks. So it is most important to represent them with as few bits as possible. In this paper, we propose an efficient method for encoding the quantized DCT blocks of motion compensated prediction (MCP) errors, which adaptively selects one of a few scanning patterns. The scanning pattern selection of an MCP error block is based on the motion compensated images which are always available at the decoder as well as at the encoder. No overhead information for the scanning patterns needs to be transmitted. Simulation results show that the average bit rate reduction amounts to 5%.

We discuss ISDB (Integrated Services Digital Broadcasting) which has a transport structure to meet the technical requirements such as the flexibility and the extensibility of broadcasting in the future. The basic configuration of the ISDB transmission signal for distribution into various transmission channels is shown. Hybrid multiplexing, which uses common fixed-length packets and structured transmission units called "slots," is introduced to construct a transmission signal for low-cost signal processing in ISDB receivers. We show that a fixed packet length of 40-240 bytes results in high transmission efficiency in a diverse range of service arrangements. Furthermore, we use transmission control methods, which show the relationship between programs and packet IDs, to select the desired program with certainty and ease.

The graph bisection problem is to partition a given graph into two subgraphs with equal size with minimizing the cutsize. This problem is NP-hard, and hence several heuristic algorithms have been proposed. Among them, the Kernighan-Lin algorithm and the Fiduccia-Mattheyses algorithm are well known, and widely used in practical applications. Since those algorithms are iterative improvement algorithms, in which the current solution is iteratively improved by interchanging a pair of two nodes belonging to different subgraphs, or moving one node from one subgraph to the other, those algorithms tend to fall into a local optimum. In this paper, we present a heuristic algorithm based on subgraph migration to avoid falling into a local optimum. In this algorithm, an initial solution is given, and it is improved by moving a subgraph, which is effective to reduce the cutsize. The algorithm repeats this operation until no further improvement can be achieved. Finally, the balance of the bisection is restored by moving nodes to get a final solution. Experimental results show that the proposed algorithm gets better solutions than the Kernighan-Lin and Fiduccia-Mattheyses algorithms.

Error-correction techniques can be used to reduce the required carrier-to-noise ratio (C/N) in digital satellite news gathering (SNG) systems. The required e.i.r.p. of a digital SNG terminal is smaller than that of conventional analog SNG RF terminals. In this paper, a Ku-band portable SNG RF terminal using a flat antenna is proposed to make the best use of these digital systems. This portable terminal uses 16 planar microstrip subarray antennas, each with a solid-state power amplifier (SSPA) mounted on its backside. The proposed RF terminal is distinctly different from a conventional RF terminal with a parabolic antenna in two ways; it is portable and it has electronic tracking capability. Electronic antenna tracking reduces the terminal setup time because precise alignment of the antenna with the satellite is not required. This paper first describes the system concept and discusses the design concept. Secondly, it then explains phase shifters and feedback loops for electronic tracking. The tracking performance of a feedback system using four subarrays is also presented with some comparisons between theoretical and measured results. Experimental results for the low side-lobe flat antenna and the SSPAs are then presented. These are the most important components of the system. The flat antenna meets the design objectives specified by ITU-R Recommendations. By orthogonally exciting the rectangular patch antenna, the flat antenna is capable of operating dual polarizations and dual frequencies (transmit/vertical polarization: 14GHz; receive/horizontal polarization: 12GHz). The SSPAs have an efficiency of 21% and an output power of 5W.

The propagation characteristics of dielectric waveguides with slanted grating structure are analyzed by using the combination of the improved Fourier series expansion method and the approximated multilayer method. The slanted grating region is appoximated by a structure with stratified thin modulated index layers. This method is effective to the guiding problems of the planar slanted grating, because the electromagnetic fields in each layer can be expressed by shifting the phase of the solution in the first layer. In this paper, numerical results are given for the grating with the rectangular and the sinusoidal profile for arbitrary slant angle. The radiation efficiencies for the grating with negative and positive slant angle are also discussed.

A particle trajectory estimation method from far electromagnetic fields are discussed in this paper. Authors have already presented a trajectory estimation method for single particle system and good agreements between a source particle trajectory and an estimated one have been obtained. For this, this paper discusses twin particles system as an examples of multi-particles systems for simplicity. First of all, it is pointed out that far electromagnetic fields from the twin particles system show quite different aspect from the single particle system using an example, radiation patterns produced by two particles which carry out circular motion. This result tells us that any trajectory estimations for general multi-particles system are almost impossible. However, it is shown that when the distance between the particles is small, the estimation method for the single particle system can be applied to the twin particles system, and that twin particles effects appear as disturbance of estimated trajectory.

In this paper, we propose the architecture of BALANCE (Better Adaptive Load-balancing through Acquiring kNowledge of Characteristic of an Environment) in which users can submit their jobs without acquiring either a status of an environment or characteristics of jobs and servers even in a widely connected heterogeneous network. The architecture of BALANCE includes three types of information bases and two types of daemons. Information bases, namely job, resource, and environment information base, manage the knowledge of job characteristics, available resources for CPUs, and status of the environment, respectively, as a proxy for users. The dispatching daemon selects an adequate server for each job using knowledge stored in the information bases. A service daemon executes each job. On completing each job, a service daemon gets a statistic of the job and returns it to the dispatching daemon where the job came from so that the statistic will be available at the next dispatching time. BALANCE enables an environment (1) to balance the load, (2) to share software functions as well as hardware facilities, and (3) to learn a user's job characteristics. We have implemented a prototype with more than 50 heterogeneous UNIX workstations connected by different networks. Two simple experiments on this prototype are presented. These experiments show a load balancing scheme that takes the characteristics of each job into account.

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.

An optimal control theory has been applied to a biological compartment system to show a method to analyze the control principle of biological system represented by compartments. Present theory has been proposed to afford a theoretical back ground and validity for the strategy of drug administration or control of the anesthetic agent in practical medicine. The instantaneous change of the concentration of a given material within a biological system has been expressed by differential equations. Each compartment has been set to be transferred a material from all other compartments and conversely each compartment sends it to all other compartments. The control input was restricted to be one kind. The performance function involved the deviation from the target value, the rate of change in concentration and the amount of the control variables. The biological system was defined to operate optimally only when the performance function has been minimized during a given time period. By the optimal control theory of Pontoriagin, above biological problem has been converted to a mathematical problem and was solved numerically by multiple shooting method. The calculated trajectory of the optimal control has been asymmetric parabolic one with the maximum at its initiation and the minimum at the middle of total reaction time. This pattern has been consistent with that of probable transient change of the concentration of anesthetic agent when it has been inhalated under the most up to date "Rapid Inhalation Induction" method. The optimal trasient change of the concentration at each compartment has beeb affected by the difference in time dependent nature and the magnitude of the transfer rate. Present theory afforded a method to analyze the control strategy of biological system expressed by compartments model and showed an availability for actual clinical medicine. The optimal control principle must be a most adequate one to describe the Homeostasis in biological system.

We discuss a processor scheduling problem for parallel logic simulation of combinational circuits. In the processor scheduling problem, to be discussed in this paper, for logic simulation using time–first method, the time needed for each gate evaluation is not given beforehand, and is not constant. This feature distinguishes the processor scheduling problem from typical task scheduling problems. First, we devise newly Algorithm MET to solve the processor scheduling problem. The key idea of Algorithm MET is to determine processor scheduling incrementally and dynamically. Then, experimental evaluations using well–known twelve benchmark combinational circuits show the usefulness of Algorithm, MET, compared with conventional static algorithms. We believe that this is a first step to implement parallel logic simulation of combinational circuits.

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.

Recently actual use of the OSI standardized protocols has begun on client-server systems of LANs, and reduction of OSI protocol overheads in high-speed networks has become more important. We studied a parallel-processing architecture for Message Handling System (MHS), which requires a large amount of protocol processing and is expected to be used widely. We implemented a prototype MHS server with performance scalable to number of CPUs, by porting an existing MHS software with minimum modification. This paper reports on the parallel processing scheme, hardware and software architecture of the prototype, as well as evaluation of the scheme based on measurement and simulation.

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.

There has been an increasing demand for telecommunication services that satisfy individual users' requirements such as personal telecommunication services and intelligent network services. This demand for advanced telecommunications services is having a great impact on the control architecture and mechanism. In this paper, we propose a new representation of processing power for telecommunications services, using TPS (Transaction Per Second), instead of BHCA, which has been the most commonly used parameter for conventional telephone networks. In developing an IN benchmark, telecommunications services are compared with the TPC-A (Transaction Processing Performance Council-A) benchmark model based on TPS. This benchmark is then used to estimate the requirements for processing power, which, in turn, indicate the necessity for a distributed control. A layered architecture, compatible architecture, and control mechanism for user services are employed to adapt to the distributed network environment.