A method to characterise the wall voltage distribution in a three-electrode AC PDP cell is discussed. The method makes use of a firing voltage loop in a two-dimensional voltage plane. From this "fingerprint," data on the relative wall voltages as well as on the non-uniformity of the wall voltages can be inferred. The properties of the loop are explained using a simple numerical model based on field line tracing. The fingerprint method is applied to analyse ramp waveforms on the scan and data electrode of a surface discharge PDP. Many features of the measurements can be understood in terms of uniform wall voltage distributions on the dielectrics covering the electrodes. A more detailed analysis, however, shows that considerable wall voltage non-uniformities can exist, which play an important role in the firing behaviour of the cell.

Performance evaluation criterion is one of the most important issues for design of network traffic control mechanisms and algorithms. Due to multiple performance objectives of network traffic control, performance evaluation criteria must include multiple performance metrics executed simultaneously, which is called integrated performance evaluation criteria. In this paper, we analyze various performance metrics of network traffic control, and propose three integrated performance evaluation criteria. One is the improvement on original Power formula; our new Power formula is based on the multi-service-class model. Another is about the fairness of user's QoS (Quality of Service) requirements (queuing delay and loss rate); especially the detailed discussion on Proportional Fairness Principle is given. And the third one is the integration of preceding two, in which the throughput, queuing delay, packet loss rate, and the fairness are considered simultaneously.

The main contribution of this work is to propose energy-efficient protocols that compute the sum of n numbers over any commutative and associative binary operator stored in n wireless sensor nodes arranged in a two-dimensional grid of size nn. We first present a protocol that computes the sum on a Wireless Sensor Network (WSN) in O(r2+(n/r2)1/3) time slots with no sensor node being awake for more than O(1) time slots, where r is the transmission range of the sensor nodes. We then go on to present a fault-tolerant protocol which computes the sum in the same number of time slots with no sensor node being awake for more than O(log r) time slots. Finally, we show that in a WSN where the sensor nodes are empowered with the ability to dynamically adjust their transmission range r during the execution of the protocol, the sum can be computed in O(log n) time slots and no sensor node needs to awake for more than O(log n) time slots.

A novel adaptive technique based on a statistical model by estimating window size for unsupervised segmentation of a set of MR images is presented. The window size estimation is achieved in the image using a MDL for mixture estimation and segmentation, and allows the technique to well reflect local characteristics of the image.

Autonomous distributed manufacturing systems (ADMS) consist of multiple intelligent components with each component acting according to its own judgments. The ADMS objective is to realize more agile and adaptive manufacturing systems. This paper presents the introduction of context-dependent agents (CDAs) in ADMS that switch strategies depending on system conditions to achieve better performance than can be realized by agents that use the same strategies under all system conditions. For the real-time job scheduling problem, the paper presents a basic CDA architecture and the results of an extensive empirical evaluation of its performance relative to other rule-based schemes based on several common indices for real-time dispatch.

A practical EB-testing-pad method, that enables higher observability of multilevel wiring LSIs without any increase of chip size, has been evaluated by using actual 0.25-µm SIMOX/CMOS devices. First, an 80k-gate logic LSI with testing pads was developed, and it was proved that observability improves from 17% to 87%. Next, two kinds of gate-chain TEGs (test element groups), with and without testing pads was developed to investigate the influence of testing pads on gate delay. It was found that the circuit delay increase due to the pads is very small, less than 2.7%. It was also found that capacitances from neighboring wires will increase only by at most 3% due to the testing pads. Thus, the testing pad method has been proved to be extremely effective in improving observability without any overhead in design.

This paper describes a novel mobile video monitoring system. The receiver is a PDA (Personal Digital Assistant) with a PHS (Personal Handy Phone system) card. The sender is a PC-based video encoding system, which is connected to an ISDN line by ISDN-TA. Functions such as camera selection, remote camera control and high-resolution snap shot are implemented. In this paper, details of the system are explained and a practicability assessment is performed. An experiment was conducted to measure the upward and downward transmission delay. From the results, the system performs consistently to a theoretical behavior. Furthermore, the performance of this system is quite practical for mobile video monitoring.

In this paper, the performance of multi-stage parallel interference cancellation receiver using forward-backward filtering channel estimation is evaluated for the W-CDMA uplink. The channel estimation employs a non-causal forward-backward-multiplication-method filter, which was originally proposed for the reception of W-CDMA random access. Results of link level simulations for data and voice traffic scenarios over Pedestrian A and Vehicular A channels are discussed in comparison with the conventional channel estimation methods of 1-slot pilot averaging, 1-slot averaging, and weighted multiple slot averaging. It is shown that the forward-backward filtering channel estimation improves performances of the interference cancellation receiver as well as that of the ordinary Rake receiver in both Pedestrian A and Vehicular A channels. With its features of short processing delay and low complexity, the forward-backward filtering channel estimation is suitable for practical implementations of multi-stage interference cancellation receivers.

Co-containing ferrite thin-film media deposited by a reactive-ECR-sputtering at a low substrate temperature of 150 degree Celsius were oxidized by ECR plasma. The magnetic properties and recording characteristics of the media were improved by the oxidation with maintaining a smooth surface. The media showed high D50 of 203 kFRPI in MIG head recording and reproduction. The Co-containing ferrite thin-film is feasible to be used as a protective overcoat layer.

This paper addresses a novel scheme for variable rate error correction coding with interleavered puncturing serially concatenated convolutional code. In order to obtain a variable coding rate, the bits of the outer coder are perforated with a given puncturing pattern, and randomly interleaved. The effect of interleavered puncturing on the overall coding performance is analyzed, and the upper bound to the bit error probability of the proposed coder is derived. Moreover, to evaluate the effectiveness of the proposed scheme some simulation results are presented with the iterative decoding procedure, in which the channel models of Rayleigh fading and additive white Gaussian noises are assumed.

This paper deals with a mathematical formulation of the scattering from a periodic surface with finite extent. In a previous paper the scattered wave was shown to be represented by an extended Floquet form by use of the periodic nature of the surface. This paper gives a new interpretation of the extended Floquet form, which is understood as a sum of diffraction beams with diffraction orders. Then, the power flow of each diffraction beam and the relative power of diffraction are introduced. Next, on the basis of a physical assumption such that the wave scattering takes place only from the corrugated part of the surface, the amplitude functions are represented by the sampling theorem with unknown sample sequence. From the Dirichlet boundary condition, an equation for the sample sequence is derived and solved numerically to calculate the scattering cross section and optical theorem. Discussions are given on a hypothesis such that the relative power of diffracted beam becomes almost independent of the width of surface corrugation.

An information retrieval model that intends to conceptually deal with the documents in the Internet is proposed. The first half of this model is a stage to select the documents, which may meet the user's long-term interests, by employing a filtering or retrieval system. The latter half is a stage for linear document arrangement and for adjacent cluster based browsing. For the document collection filtered out, similarity matrices are computed and then the documents are arranged such that the highly similar ones are adjacently placed. By this treatment the documents are considered to form the clusters, some of which are adjacently placed when they include similar documents. A user can satisfy her/his needs by first browsing in the clusters containing documents highly similar to a query, and next by extending the browsing process into the clusters adjacent to the ones just examined. In the adjacent clusters the documents having no keywords common to but conceptually related to the query can be found. Computational and statistical evaluations were done on two standard test collections. A virtual space navigator is also designed by using JAVA to assist a user in the browsing task.

In this paper, a method is proposed to construct an n-out-of-n visual secret sharing scheme for gray-scale images, for short an (n,n)-VSS-GS scheme, which is optimal in the sense of contrast and pixel expansion, i.e., resolution. It is shown that any (n,n)-VSS-GS scheme can be constructed based on the so-called polynomial representation of basis matrices treated in [15],[16]. Furthermore, it is proved that such construction can attain the optimal (n,n)-VSS-GS scheme.

Scattering of a plane wave obliquely incident on a meteor trail is studied using the full wave treatment by treating the trail as a stratified column which has Gaussian radial electron distribution. Due to the coupling of the fields, the coupled equations have to be solved simultaneously. They are treated in matrix form, so the uncoupled and the coupled components can be distinguished. Based on the oblique scattering geometry, the effects of the variation of the communication range and the trail orientation are investigated. In the case of the variation of the communication range, results are in accordance with the approximate models but they are in contrast in the case of the variation of the trail orientation. Calculated waveforms are compared with the experimental echo shapes. It is found that they are in good agreement with each other. Furthermore, a duration comparison indicates that the electron line densities of most of the received signals are in the transition region.

The radar cross section (RCS) of a dielectric-coated cylindrical cavity was measured and the measurements were compared with those calculated according to the iterative physical optics (IPO). The IPO analysis used the equivalent-impedance boundary condition (EIBC) based on transmission-line theory which takes into account the thickness of the coating. It was consequently found that this condition is much more effective than the ordinary-impedance boundary condition based on the intrinsic impedance of the material.

To classify the significant wavelet coefficients into edge area and noise area, a morphological clustering filter applied to wavelet shrinkage is introduced. New methods for wavelet shrinkage using morphological clustering filter are used in noise removal, and the performance is evaluated under various noise conditions.

Since the penetration of VSAT services is rapidly increasing, more earth stations will operate around airports than is currently true. This makes it essential to evaluate accurately and efficiently the impairment of received signals due to blockage by aircraft. This paper proposes developing an aircraft model using a thin, planar polygon to represent the aircraft projection and to apply GTD with corner diffraction terms. The effectiveness and applicability of the method is then examined numerically. It is demonstrated that the results measured in the Ku-band around two airports are a good match with the numerical simulations even when the distance between the aircraft and the stations is small.

A circuit that carries out an Hadamard transform of an input image using the pulse width modulation technique is proposed. The proposed circuit architecture realizes the function of an Hadamard transform with a full-size pixel image. A test chip that we designed and fabricated integrates 64 64 pixels in a 4.9 mm 4.9 mm area, with 0.35 µm CMOS technology. The functional operation and linearity of this chip are measured. An image processing application utilizing this chip is demonstrated.

In this letter we present a new way for computing generalized eigenvalue problems in engineering applications. To transform a generalized eigenvalue problem into an associated problem for solving nonlinear dynamic equations by using optimization techniques, we can determine all eigenvalues and their eigenvectors for general complex matrices. Numerical examples are given to verify the formula of dynamic equations.

Server performance is a major issue in improving the overall performance of the World Wide Web (WWW). This article introduces a dynamic mirroring-based approach to improve WWW servers' performance. In contrast to static mirroring, where mirror servers are allocated statically, our mirror servers' setup is driven by network traffic measurement. Performance in terms of latency is inferred from a queuing model. According to this model we show that latency of an overloaded server can be tuned by delegating a portion of the load to a cooperative mirror server. Cost is evaluated by the amount of load hosted by the mirror servers. The goal is then to keep the latency within a tolerable threshold, while minimizing the delegated load. This problem is formulated as a constrained optimization problem where the task is to assign a portion of load corresponding to each document to each mirror server. As the result of this work, we will have a balanced load among the servers, and a smoother traffic along the Internet, as well. Empirical results show that this approach can guarantee to maintain the performance while showing a significant decrease in the amount of load transferred to the mirror servers.