In order to pave the way to B-ISDN, one of the most important issues for network providers is to identify the most efficient B-ISDN introduction strategy. This paper focuses on the costs of introducing ATM transmission systems into backbone transport networks which must provide highly reliable broad band transmission capability. In this context, the main rival to ATM is Synchronous Transfer Mode (STM); recent Synchronous Digital Hierarchy (SDH) equipment supports the establishment of advanced STM-based high speed transport networks. This paper offers a cost comparison of ATM and STM based backbone transport networks. A digital path network in STM has a hierarchical structure determined by the hierarchical multiplexing scheme employed. The minimum cost STM path network can only be determined by developing a path design method that considers all hierarchical path levels and yields the optimum balance of link cost and node cost. Virtual paths have desirable features such as non-deterministic path bandwidth and non-hierarchical and direct multiplexing capability into high speed optical transmission links. These features make it possible to implement a non-hierarchical VP network with ATM cross connect systems which can handle any bandwidth VP with a universal cell switching function. This paper shows that the non-hierarchical VP routing, which strongly minimizes link cost, can be implemented without significantly increasing node cost. Network design simulations show that the virtual path scheme, possible only in an ATM network, yields the most cost effective path network configuration.

A cumulant-based lattice algorithm for multichannel adaptive filtering is proposed in this paper. Proposed algorithm takes into account the advantages of higer-order statistics, that is, improvement of estimation accuracy, blindness to colored Gaussian noise and the possibility to estimate the nonminimum-phase system etc. Without invoking the Instrumental Variable () method as used in other papers [1], [2], the algorithm is derived directly from the recursive pseudo-inverse matrix. The behavior of the algorithm is illustrated by numerical examples.

A new anti-static technology to neutralize static electricity by high energy photon irradiation has been developed. Ions and electrons required for neutralization are generated by ionization of gas molecules in the vicinity of a charged substance. Gas molecules absorbs photons to become ionized. The wavelength chosen for the irradiation depends on the neutralization atmosphere. Soft X-rays with wavelength over about 1 are effective in air or O2 gas at pressure higher than several hundreds Torr. Vacuum UV-rays with wavelength below about 1350 is effective in N2 gas, Ar gas, or reduced pressure ambients. These methods feature excellent neutralization capa-bility. Electrostatic potential can be reduced to 0 V in a very short time without encountering the problems of which conven-tional corona discharge ionizers.

The realization of scientific manufacturing of ULSIs in the 21st century will require the development of a technical infrastructure of "Ultra Clean Technology" and the firm establishment of the three principles of high performance processes. Three principles are 1)Ultra Clean Si Wafer Surface, 2)Ultra Clean Processing Environment, and 3)Perfect Parameter controlled process. This paper describes the methods of resolving the problems inherent in Ultra Clean Technology, taking as examples issues in quarter-micron or more advanced semiconductor process and manufacturing equipment, particularly when faced with the challenges of plasma dry etching. Issues indispensable to the development of tomorrow's highly accurate and reliable plasma dry etching equipment are the development of technologies for the accurate measurement of plasma parameters, ultra clean gas delivery systems, chamber cleaning technology on an in-situ basis, and simulating the plasma chemistry.This paper also discusses the standardization of semiconductor manufacturing equipment, which is considered one of the ways to reduce the steep rise in production line construction costs. The establishment of Ultra Clean Technology also plays a vital role in this regard.

A fast and stable algorithm for locating a desired eigenvalue and its corresponding eigenvector is presented. Its effectiveness is shown through a numerical simulation. The proposed algorithm is fast and numerically accurate enough to be applied to a real application.

This paper proposes an adaptive modulation system with a punctured convolutional code for land mobile communications to achieve high quality, high bit rate, and high spectral efficient data transmission in multipath fading environments. The proposed system adaptively controls the coding rate of the punctured convolutional code, symbol rate, and modulation level according to the instantaneous fading channel conditions. During good channel conditions, the modulation parameters are selected to increase the transmission rate as much as possible with satisfying a certain transmission quality. As channel conditions become worse, lower rate modulation parameters are applied or transmission is stopped. The performances in fading environments are evaluated theoretically and by computer simulations. The results show that the proposed system can realize higher quality transmission without the degradation in average bit rate compared to conventional adaptive modulation systems.

This paper overviews fiber-oriented wireless communication systems, particularly in the area of microcell systems. The benefits of fiber-oriented wireless systems are discussed focusing on an application board scheme to facilitate new service deployment in light of intelligent networks. Dynamic range improvement technologies to remove interference are highlighted. Overall system performance is calculated for an economical FP-LD. Furthermore, effective modem use and a potential diversity technique are introduced. This strategy will play a role in realizing flexible fiber-optic subscriber networks.

A new transmit permission control scheme applicable in multi-cell communication systems is proposed. In this scheme, by prohibiting the transmissions from the users with relatively high propagation loss to their connecting hub stations, level of multiple access interference is decreased, and hence throughput characteristics are improved. Moreover, we continue our discussion to propose two adaptive forms of the transmit permission control scheme, in which the prohibition condition becomes more intelligent by considering the level of the offered traffic loads to hub stations. These methods are utilized in a slotted Aloha random transmission of the spread spectrum packets, and on the uplinks of a low earth orbit satellite communication system as an example of the multi-cell systems. It is shown that the adaptive schemes exhibits significantly improved characteristics at all offered traffic loads in these systems.

This paper describes a CDMA cellular system based on adaptive interference cancellation (CDMA-AIC) with a large capacity. In the CDMA-AIC, each base station employs a single-user type adaptive interference canceller (AIC), which consists of a fractionally chip-spaced code-orthogonalizing filter (COF) and a coherent detector. The AIC adaptively removes power-dominant multiple-access interferences (MAIs) in the cellular system, regardless of whether they are intra-cell interferences or inter-cell interferences, without any information about them, such as spreading codes, signal received timings and channel parameters. Evaluation under the multiple-cell environment demonstrates that the reverse link capacity of the CDMA-AIC with QPSK modulation is 3.6 times as large as the capacity of the CDMA without MAI cancellation. Further, the capacity is less sensitive to transmission power control errors than that of the conventional CDMA systems.

Several papers have been shown equalization in the reception side. However, equalization in transmission side that is partial response signaling (PRS) or precoding is also possible in a two-way interactive communication such as time or frequency division duplex (TDD of FDD). This paper proposes and investigates a system which includes a transmission equalization and reception equalization based on an array antenna. This system is the extension in spatial and temporal domains. The channel capacity can be improved in the super channel which includes the transmitter and receiver array antenna.

A regeneration technology of fluorite (CaF2) from spent HF and Buffered HF (BHF) has been investigated. The mechanism of "direct conversion" of granular calcite (CaCO3) into granular fluorite has revealed and several special phenomena are first found to be efficient. An advanced system has been developed. This system regenerates granular fluorite by conversion of granular calcite filled in a column. High purity and low water fluorite is recovered as a substitute for natural fluorspar (CaF2). The fluorine concentration in the processed effluent is minimized to a level of 5 ppm. The separation of the HF processing line and BHF processing line equipped ammonia stripper is an important to system design because ammonia generated from BHF significantly retards the conversion efficiency from CaCO3 to CaF2. The new system reforming the conventional slaked lime processing solves long-pending problem, resulting in a very compact system with a very small amount of product.

In this paper, we study three-dimensional motion estimation using optical flow. We construct a weighted quotient-form objective function that provides an unbiased estimator. Using this objective function with a certain projection operator as a weight drastically reduces the computational cost for estimation compared with using the maximum likelihood estimator. To reduce the variance of the estimator, we examine the weight, and we show by theoretical evaluations and simulations that, with an appropriate projection function, and when the noise variance is not too small, this objective function provides an estimator whose variance is smaller than that of the maximum likelihood estimator. The use of this projection is based on the knowledge that the depth function has a positive value (i. e., the object is in front of the camera) and that it is generally smooth.

A new observation technique for process-induced micro-defects in ULSI using a combination of anodic oxidation and chemical removal of the oxide has been developed. Enhanced oxidation has occurred at the defect region due to the stress field and then craterlike delineation has been formed after oxide removal. AFM and SEM observation of the micro-defects induced by ion implantation and applications using this tech-nique to the failure analysis of MOS device fabrication are presented.

This paper describes Kleenean coefficients that are a subset of Kleenean functions for use in representing multiple-valued logic functions. A conventional multiple-valued sum-of-products expression uses product terms that are the MIN of literals and constants. In this paper, a new sum-of-products expression is allowed to sum product terms that also include variables and complements of variables. Since the conventional sum-of-products expression is complete, so also is the augmented one. A minimization method of the new expression is described besed on the binary Quine-McCluskey algorithm. The result of computer simulation shows that a saving of the number of implicants used in minimal expressions by approximately 9% on the average can be obtained for some random functions. A result for some arithmetic functions shows that the minimal solutions of MOD radix SUM, MAX and MIN functions require much fewer implicants than those of the standard sum-of-products expressions. Thus, this paper clarifies that the new expression has an advantage to reduce the number of implicants in minimal sum-of-products expressions.

A microphone array system with multi-stage processing for speech enhancement is presented in this paper. Two beamformers with uniform directional patterns, one aimed at the target source and the other at the interfering sources, convert the multi-channel inputs into two data sequences. A novel microphone array structure with a small aperture has been designed to obtain the dual beamformers. The outputs of the two beam-formers are then presented to a post-processing stage to further improve the quality and intelligibility of the speech signal. The post-processing stage can be selected from one of three different algorithms that are presented, which are suitable for different acoustic environments. Applications for such a system include hands-free telephony, teleconferencing and also special situations where speech signals must be picked up in an extremely noisy acoustic environment in which the microphones are hidden (e.g. in a forensic covert recording system).

In order to reduce the ever increasing cost for ULSI manufacturing due to the complexity of integrated circuits, dramatic simplification in the logic LSI architecture as well as the very flexible circuit configuration have been achieved using a highfunctionality device neuron-MOSFET (γMOS).In γMOS logic circuits, however, computations based on the multiple-valued logic is the key for enhancing the functionality. Therefore, much higher accuracy of processing is required. After brief description of the operational principle of γMOS logic, the relationship between the number of multiple logic levels and the functionality enhancement is discussed for further enhancing the functionality of γMOS logic circuits by increasing the number of multiple logic levels, and the accuracy requirements for the manufacturing processes are studied. The order of a few percent accuracy is required for all principal device structural parameters when it is aimed to handle 50-level multiple-valued variable in the γMOS logic circuit.

Co-channel interference is a major factor limiting spectral efficiency of a cellular radio system. The trellis-coded co-channel interference canceller (TCC) leading to the significant increase of traffic capacity of a cellular system has been proposed. In this scheme, a maximum-likelihood sequence estimation implemented with the Viterbi algorithm is extended to estimate both desired signal and co-channel interference, and combined with trellis-coded modulation to enhance the co-channel interference cancelling capability. The complexity of TCC grows exponentially with the channel memory and the constraint length of the trellis encoder. In this paper, two reduced-state sequence estimation algorithms, namely, the delayed decision feedback sequence estimation and the M-algorithm, are applied to TCC and their performance is compared. In addition, effective trellis coded modulation schemes to reduce the computational complexity are proposed. The performance of these schemes is examined through simulations, and compared to that of a conventional interference canceller.

Recently applications of Hilbert curves are studied in the area of image processing, image compression, computer hologram, etc. We have proposed a fast Hilbert scanning algorithm using lookup tables in N dimensional space. However, this scan is different from the one of previously proposed scanning algorithms. Making the lookup tables is a problem for the generation of several Hilbert scans. In this note, we describe a method of making lookup tables from a given Hilbert scan which is obtained by other scanning methods.

We have developed a complete chromium oxide (Cr2O3) passivated gas tubing system by introducing ferritic stainless steel instead of conventional austenitic stainless steel (SUS316L). 100% Cr2O3 passivation film can be formed on electropolished ferritic stainless steel surface because the diffusion coefficient of Cr in ferritic stainless steel is 104 times larger than in austenitic stainless steel. In ferritic stainless steel, moreover, welded bead surface is covered by 100% Cr2O3 pas-sivated film by an introduction of advanced welding technology.

Understanding unknown objects in images is one of the most important fields of the computer vision. We are confronted with the problem of dealing with the ambiguity of the image information about unknown objects in the scene. The purpose of this paper is to propose a new object recognition method based on the fuzzy relation system and the fuzzy integral. In order to deal with the ambiguity of the image information, we apply the fuzzy theory to object recognition subjects. Firstly, we define the degree of similarity based on the fuzzy relation system among input images and object models. In the next, to avoid the uncertainty of relations between the input image and the 2-D aspects of models, we integrate the degree of similarity obtained from several input images by the fuzzy integral. This proposing method makes it possible to recognize the unknown objects correctly under the ambiguity of the image information. And the validity of our method is confirmed by the experiments with six kinds of chairs.