Polarization transformation characteristics of a statified slab consisting of uniaxial chiral layers are investigated. It is assumed that a plane electromagnetic wave with arbitrary polarization is normally incident from free space on the stratified slab, which is located on a dielectric substrate. Note that the electric field inside a uniaxial chiral layer is expressed as a sum of four plane waves with different wavenumbers. The wavenumbers are found by seeking non-trivial solutions of the constitutive relations with Maxwell's equations. The electric field components of the transmitted and reflected waves can be obtained from a chainmatrix formalism. The powers and the Stokes parameters of the two waves are represented in terms of their electric field components. As is well known, the Stokes parameters uniquely describe every possible state of polarization of a plane wave. Numerical results are presented for two types of uniaxial chiral structure. The cross- and co-polarized powers and the Stokes parameters of the transmitted and reflected waves are computed for the incident plane wave of linear polarization. The results demonstrate a significant polarization transformation of the transmitted wave. Then it is shown that the stratified slab can be used as efficient polarization-transformation transmission filters active at some frequency band.

In this paper, we illustrate the analysis of microstrip structures with a large number of unknowns using the sparse-matrix/canonical grid method. This fast Fourier thansform (FFT) based iterative method reduces both CPU time and computer storage memory requirements. We employ the Mixed-Potential Integral Equation (MPIE) formulation in conjunction with the RWG triangular discretization. The required spatial-domain Green's functions are obtained efficiently and accurately using the Complex Image Method (CIM). The impedance matrix is decomposed into a sparse matrix which corresponds to near interactions and its complementary matrix which corresponds to far interactions among the subsectional current elements on the microstrip structures. During the iterative process, the near-interaction portion of the matrix -vector multiplication is computed directly as the conventional MPIE formulation. The far-interaction portion of the matrix-vector multiplication is computed indirectly using fast Fourier transforms (FFTs). This is achieved by a Taylor series expansion of the Green's function about the grid points of a uniformly-spaced canonical grid overlaying the triangular discretization.

We propose a method to search all the zeros of a complex function in a given compact region D Cn. The function f: Cn Cn to be considered is assumed to consist of polynomial and transcendental terms and to satisfy f (x) Rn for any x Rn. Using the properties of such a complex function, we can compute the number of zeros and determine the starting points of paths on the boundary of D, which attain all the zeros of f in D without encountering a singular point. A piecewiselinear approximation of the function on a triangulation is used for both computing the number of zeros and following the paths.

This paper describes a mobile information access system based on a multi-agent architecture. With the rapid progress of wireless data communications, mobile Internet access will be more and more popular. In mobile environments, user location plays an important role for information filtering and flexible communication service. In this paper, we propose a mobile information service system where a user with a handy terminal accesses Internet in an open air to look up map information and related town information. Each user information is managed by an independent agent process. And the agent provides each user with a personal service collaborating with other applications. A map-based information service example based on this architecture is also described.

We present theoretical results on the convergence of iterative methods for the solution of linear differential-algebraic equations arising form circuit simulation. The iterative methods considered include the continuous-time and discretetime waveform relaxation methods and the Krylov subspace methods in function space. The waveform generalized minimal residual method for solving linear differential-algebraic equations in function space is developed, which is one of the waveform Krylov subspace methods. Some new criteria for convergence of these iterative methods are derived. Examples are given to verify the convergence conditions.

In this paper, we introduce a Shared Multiple Rooted XOR-based Decomposition Diagram (XORDD) to represent functions with multiple outputs. Based on the XORDD representation, we develop a synthesis algorithm for general Exclusive Sum-of-Product forms (ESOP). By iteratively applying transformations and reductions, we obtain a compact XORDD which gives a minimized ESOP. Our method can synthesize larger circuits than previously possible. The compact ESOP representation provides a form that is easier to synthesize for XOR heavy multi-level circuits, such as arithmetic functions. We have applied our synthesis techniques to a large set of benchmark circuits in both PLA and combinational formats. Results of the minimized ESOP forms obtained from our synthesis algorithm are also compared to the SOP forms generated by ESPRESSO. Among the 74 circuits we have experimented with, the minimized ESOP's have fewer product terms than those of SOP's in 39 circuits.

Nonuniform transmission lines are crucial in integrated circuits and printed circuit boards, because these circuits have complex geometries and layout between the multi layers, and most of the transmission lines possess nonuniform characteristics. In this article, an efficient numerical method for analyzing nonuniform transmission lines has been presented by using the Chebyshev expansion method and moment techniques. Efficiency on computational cost is demonstrated by numerical example.

A Unique Input/Output (UIO) sequence for the state J of a protocol is a sequence of input/output pairs that is unique to state J. Obtaining UIO sequences from the protocol specification is a very important problem in protocol conformance testing. Let n and m be the total number of states and transitions of the protocol, respectively, and dmax be the largest outdegree of any state, W. Chun and P. D. Amer proposed an O(n2(dmax)2n-1) algorithm to obtain the minimum-length UIO sequences (where the length refers to the number of input/output pairs). However, n and m are normally very large for real protocols. In this paper, we propose an O(n*m) algorithm for obtaining UIO sequences. In theory, our algorithm yields a UIO sequence which contains at most n1 input/output pairs. In experimentation, ten protocol examples collected from recent papers, the ISO TP0 protocol, the ISDN Q. 931 network-side protocol, and the CCITT X. 25 protocol show that in average the obtained UIO sequences are only 11.8% longer than the minimum-length ones, and 97.4% of the existent UIO sequences can be found. And our algorithm is extended for minimizing the cost of UIO sequences and for obtaining synchronizable UIO sequences, which have not been achieved by any algorithm proposed earlier.

High-Tc SQUID was applied to the detection of magnetized fine particle moving at high speed. Two types of SQUIDs were used. One was a large washer type and the other was a flux transformer type. Their Josephson junctions were step edge type. The iron particle was attached on a nylon wire and scanned under the SQUID. High-Tc SQUID detected an iron particle of 50 µm diameter running at 800 m/min. It was shown that the magnetic field measured by the SQUID was proportional to the volumer of the particle and is inversely proportional to the distance between the SQUID and the particle. This technique using high-Tc SQUID is hopeful not only to wire production line but also for the processing of food and medicine, etc.

In this paper we propose a comprehensive approach to physical design based on the constraint paradigm. Bounds on the most critical circuit parasitics are automatically generated to help designers and/or physical design tools meet a set of high-level specifications. The constraint generation engine is based on constrained optimization, where various parasitic effects on interconnect and devices are accounted for and dealt with in different manners according to their statistical behavior and their effect on performance.

In layout design of transport-processing FPGAs, it is required that not only routing congestion is kept small but also circuits implemented on them operate with higher operation frequency. This paper extends the proposed simultaneous placement and global routing algorithm for transport-processing FPGAs whose objective is to minimize routing congestion and proposes a new algorithm in which the length of each critical signal path (path length) is limited within a specified upper bound imposed on it (path length constraint). The algorithm is based on hierarchical bipartitioning of layout regions and LUT (Look Up Table) sets to be placed. In each bipartitioning, the algorithm first searches the paths with tighter path length constraints by estimating their path lengths. Second the algorithm proceeds the bipartitioning so that the path lengths of critical paths can be reduced. The algorithm is applied to transport-processing circuits and compared with conventional approaches. The results demonstrate that the algorithm satisfies the path length constraints for 11 out of 13 circuits, though it increases routing congestion by an average of 20%. After detailed routing, it achieves 100% routing for all the circuits and decreases a circuit delay by an average of 23%.

This paper proposes cell-attached frame encapsulation schemes in which encapsulation processing can be performed without cell reassembly. The proposed schemes are especially useful for a global networking service platform to integrate widely distributed user LANs into a single internetwork. The platform itself is an ATM-based frame forwarding network composed of access networks and a core network. These elemental networks are interconnected via edge nodes. In order to improve network interworking performance, these edge nodes should perform encapsulation processing without cell reassembly. Our proposal solves this problem. In the proposed schemes, when the first cell of a cell-divided access network frame arrives at an ingress edge node, a core-header-cell is generated from the IP header described in the first cell payload. This core-header-cell is first transmitted and then succeeding incoming cells including the first cell are forwarded cell-by-cell as soon as they arrive. Since cell-by-cell forwarding-processing reduces frame forwarding latency and cell buffer capacity, these schemes are effective from the viewpoint of both performance improvement and cost reduction.

This paper presents a new generation method of the periodic orthogonal numerical sequences with small maximum amplitude. In the generation method, complex exponential sequences are used as the generating sequences and such periodic orthogonal numerical sequences are constructed from the discrete Fourier transform of the generating sequences. Until now, there has not been found a generation algorithm to derive such sequences with any period. It is shown that the proposed generation method can derive periodic orthogonal real sequences with the maximum amplitude less than 1.5 for the period 1N200 and periodic orthogonal coplex sequences with all the sbsolute amplitude value of 1 for any period.

This paper presents a novel way of evaluating architecture of embedded custom DSPs which helps designers optimizing the datapath configuration and the instruction set. Given a datapath structure, it evaluates the performance in terms of the estimated number of steps to execute the target program on the datapath. A concept of "parallel constraint" is newly introduced, which enables evaluation of the impact of instruction format design on the performance without explicity specifying the instruction format. The number of execution steps is estimated by a combination of static analysis and dynamic analysis. It enables fast and precise estimation of actual performance in the early design stage. We have developed an architecture evaluation system based on the presented method and applied it to some actual design of signal processors. We demonstrate the accuracy of estimation and the usefulness of the method through its applications.

The present study investigated the human ability to selectively process pictures and words in free recall. We explored whether successful bias towards a subset of priority items occurs at the expense of the remaining items-i.e., whether successful priority item bias necessitates the dumping of information related to non-priority items. It has been shown that an increase in the percentage of correct recalls to items given priority in the pre-test instructions induces a decrease in the percentage of correct recalls for non-priority items. Even in a free recall experimental paradigm, the information dumping phenomenon was observed. However, there were no effects of stimulus presentation time and stimulus modality (picture vs. word) on the percentage of correct recalls detected.

A new scheme based on hierarchical information organization and situation awareness to support network manager in failure localization is proposed. This paper integrates the situation theory for the needs of fault management to model the states and events. As the result, the proposed information model includes four fault management viewpoints to support situational, functional, logical and physical analysis within the respective networks. Object-oriented analysis is applied to construct the information. The correlation of network situation is derived by description logic. The proposed classification algorithm is applied to solve the situation awareness problem. By using this proposal the correlation performance is enhanced to logarithmic order.

In this paper we suggest the "goodness" of models using the imformation criterion AIC. The information criterion AIC is a statistic to estimate the badness of models. When we usually make the fuzzy rules, we aim to minimize inference error and the number of rules. But these conditions are the criteria to acquire an optimum rule-model by using the training data. In the general case of fuzzy reasoning, we aim to minimize the inference error for not only given training data, but also unknown data. So we have introduced a new information criterion based on AIC into the appraised criterion for estimating the acquired fuzzy rules. Experimental results are given to show the validity of using AIC.

Key technologies are presented for enhancing the reusability of software in communication switching node systems along with the results obtained from porting software between several types of node systems, including N-ISDN, B-ISDNs, and Intelligent Networks. A reusable software platform based on object-oriented designing and programming techniques has been established and mechanisms for reusing object classes has been developed. Analysis of the reusability showed that this platform can be applied to various types of communication systems and that an average of more than three quarters of a system's programs can be ported. By using our software reuse framework to develop software components, we were able to reduce the time needed to develop device management programs by about 30%. Furthermore, about 80% of these programs can be ported to other systems, so introducing this platform improves software programming productivity.

This paper introduces a new recursive factorization of the polynomial, 1-zN, over the real numbers when N is an even composite integer. The recursive factorization is applied for efficient computation of the discrete Fourier transform (DFT) and the cyclic convolution of real sequences with highly composite even length.

In this paper we propose two methods, named the time smoothing and the scale smoothing respectively, to reduce the Gibbs overshoot in continuous wavelet transform. In is shown that for a large kind of wavelets the scale smoothing cannot remove the Gibbs overshoot completely as in the case of Fourier analysis, but it is possible to reduce the overshoot for any wavelets by choosing the smoothing window functions properly. The frequency behavior of scale smoothing is similar to that of the time smoothing. According to its frequency behavior we give the empirical conditions for selecting the smoothing window functions. Numerical examples are given for illustrations.