A new approach to 3-D profilometry for the white light interferometric (WLI) is presented. The proposed method is the extended depth from focus (EDFF) that determine the zero optical path difference (OPD) from the quantity of fringe contrast degradation of white light interferometer. In the method, the variance of the mismatch function and the modified local variance function are used as the focus measures. The method has a theoretically unlimited range and can profile with subpixel accuracy both optically rough and smooth surfaces without changing algorithm.

The Sinclair scattering matrix is defined in a fixed radar range. If a radar target extends in the range direction, the reflected signal or the compound scattering matrix will undergo interaction of multiple reflections. Since scattering matrix is subject to target parameters such as shape, size, orientation, material, and radar parameters as frequency, polarization, and incidence angle, it is difficult to specify a representative scattering matrix of a general target. Therefore we choose the simplest target, wire, and its scattering matrix to examine the effect of targets aligned in the range direction with respect to the compound scattering matrix. First, we present a simple formula for the compound scattering matrix of wires with the phase difference due to spacing. Then, we employed the FDTD method to examine the scattering phenomena, changing the spacing in the range direction. The FDTD result reveals that two wires can become sphere (plate) and dihedral corner reflector (diplane) component generators; and that four wires can become a good helix component generator. These phenomena are verified with a laboratory measurement. From the result, the target decomposition should be carefully carried out in terms of range. If a range resolution of a radar is not high enough, the scattering matrix of the desired target may be affected by the targets behind.

This paper presents a new data hiding scheme under fractal image generation via Fourier filtering method for Computer Graphics (CG) applications. The data hiding operations are achieved in the frequency domain and a method similar to QAM used in digital communication is introduced for efficient embedding in order to explore both phase and amplitude components simultaneously. Consequently, this scheme enables us not only to generate a natural terrain surface without loss of fractalness analogous to the conventional scheme, but also to embed larger amounts of data into an image depending on the fractal dimension. This scheme ensures the correct decoding of the embedded data under lossy data compression such as JPEG by controlling the quantization exponent used in the embedding process.

This report describes an acceleration technique to synthesize time-domain macromodels of interconnects using FDTD method. In FDTD calculation, the characteristic impedance of the interconnect is inserted into every terminal in order to damp quickly the transient waveforms. Additionally, an efficient technique for analyzing the macromodels is proposed. We demonstrate the efficiency of this method with examples.

In this paper, we propose a realtime concatenation technique between basic skeletal motions obtained by the motion capture technique and etc. to generate a lifelike behavior for a humanoid character (avatar). We execute several experiments to show the advantage and the property of our technique and also report the results. Finally, we describe our applied system called WonderSpace which leads participants to the exciting and attractive virtual worlds with humanoid characters in cyberspace. Our concatenation technique has the following features: (1) based on a blending method between a preceding motion and a succeeding motion by a transition function, (2) realizing "smooth transition," "monotone transition," and "equivalent transition" by the transition function called paste function, (3) generating a connecting interval by making the backward and forward predictions for the preceding and succeeding motions, (4) executing the prediction under the hypothesis of "the smooth stopping state" or "the state of connecting motion", (5) controlling the prediction intervals by the parameter indicating the importance of the motion, and (6) realizing realtime calculation.

This paper describes how the image sequences taken by a stationary video camera may be effectively processed to detect and track moving objects against a stationary background in real-time. Our approach is first to isolate the moving objects in image sequences via a modified adaptive background estimation method and then perform token tracking of multiple objects based on features extracted from the processed image sequences. In feature based multiple object tracking, the most prominent tracking issues are track initialization, data association, occlusions due to traffic congestion, and object maneuvering. While there are limited past works addressing these problems, most relevant tracking systems proposed in the past are independently focused to either "occlusion" or "data association" only. In this paper, we propose the KL-IMMPDA (Kanade Lucas-Interacting Multiple Model Probabilistic Data Association) filtering approach for multiple-object tracking to collectively address the key issues. The proposed method essentially employs optical flow measurements for both detection and track initialization while the KL-IMMPDA filter is used to accept or reject measurements, which belong to other objects. The data association performed by the proposed KL-IMMPDA results in an effective tracking scheme, which is robust to partial occlusions and image clutter of object maneuvering. The simulation results show a significant performance improvement for tracking multi-objects in occlusion and maneuvering, when compared to other conventional trackers such as Kalman filter.

This paper describes a random access memory (RAM, sometimes also called an array) test scheme that has the following attributes: (1) Can be used in both built-in mode and off chip/module mode. (2) Can be used to test and diagnose naked arrays. (3) Fault diagnosis is simple and is "free" for some faults during test. (4) Is never subject to aliasing. (5) Depending upon the test length, it can detect many kinds of failures, like stuck-cells, decoder faults, shorts, pattern-sensitive, etc. (6) If used as built-in feature, it does not slow down the normal operation of the array. (7) Does not require storage of correct responses. A single response bit always indicates whether a fault has been detected. Thus, the storage requirement for the implementation of the test scheme is zero. (8) If used as a built-in feature, the hardware overhead is very low.

There are more and more information services provided on the wireless networks. Due to long network delay of wireless links, transactions will be long-lived transactions. In such a situation, the occurrence of handoff is inevitable, and thus a wireless link held by a mobile unit crossing cell boundaries might be forced to terminate. It is undesirable that an active transaction is forced to terminate. A queueing scheme has been proposed to solve the problem of forced termination of transactions in our previous research. However, when 2PL protocol is employed, suspending an active transaction will elongate the lock holding time and thus degrade the system performance. In this paper, we propose two guard channel schemes (GCS), static and dynamic, to reduce the probability of forced termination of transactions. In dynamic GCS, the number of channels reserved in a base station is dynamically assigned according to the number of transaction calls which may handoff to this cell while the number of guard channels is fixed in static GCS. An analytic model based on Markov chain is derived to evaluate the system performance. The correctness of this model is verified by simulation. The experimental results show that a significant improvement is achieved by using the dynamic GCS.

Modeling a complicated system as a multi-agent system is one of the most promising ways of designing a large, complex system. If we can assume that each agent in a multi-agent system has mental states (beliefs, knowledge, desires and so on), we can formalize each agent's behaviors in an abstract way without being bothered by system implementation details. We present semantic structures that are useful for representing belief states in multi-agent environments. One of the structures is a restriction of partial Kripke structures studied by Jaspars and Thijsse: we assume that each agent can access from a state of a structure to at most one state. We call the restricted structures only-child partial Kripke structures. We show some properties of only-child partial Kripke structures. Another structure is a restriction of the alternate nonstandard structures defined by Fagin et al. to deal with the logical-omniscience problem. We show several relationships between partial Kripke structures and the restriction of alternate nonstandard structures. Using the results, we show that the outputs of a belief estimation algorithm we previously developed can be characterized by using only-child partial Kripke structures. Finally, we show that only-child partial Kripke structures are more appropriate for the belief estimation problem than the restricted nonstandard structures.

Phase locked loops (PLL's) are well known as a threshold extension demodulator for analogue FM signals. This capability may lead to the low bit error rate demodulation for digital FM signals. A PLL has also its native frequency tracking ability and is suited to the demodulation of the signals having large Doppler shifts, for example signals from Low Earth Orbit (LEO) satellites. In this paper, we study the demodulation scheme of Continuous Phase FSK (CPFSK) and Gaussian filtered MSK (GMSK) signals using a Digital Signal Processing type Digital PLL (DSP DPLL). First we propose a DSP DPLL completely equivalent to an Analog PLL (APLL). Next we adopt the sequence estimation scheme to compensate the Inter-Symbol Interference (ISI) associated with the finite loop bandwidth of the DSP DPLL. Through computer simulations it is clarified that the proposed DSP DPLL with sequence estimator can achieve better BER performance compared with the conventional Limiter Discriminator (LD) detection on the AWGN channel. We have also shown that the DSP DPLL with sequence estimator has excellent BER characteristics on Rician fading channels having actual large Doppler shifts.

A uniquely parsable unification grammar (UPUG) is a formal grammar with the following features: (1) parsing is performed without backtracking, and (2) each nonterminal symbol can have arguments, and derivation and parsing processes accompany unification of terms as in Prolog (or logic programming). We newly introduce a uniquely parallel parsable unification grammar (UPPUG) by extending the framework of a UPUG so that parallel parsing is also possible. We show that, in UPPUG, parsing can be done without backtracking in both cases of parallel and sequential reductions. We give examples of UPPUGs where a given input string can be parsed in sublinear number of steps of the length of the input by parallel reduction.

A broadcast distribution system (BDS) is a system for the distribution of digital contents over broadcast channel where the data supplier broadcasts the contents in encrypted form and gives each subscriber a decoder containing a secret decryption key. A traitor is a subscriber who offers the information which allows to decrypt the broadcast. When a pirate decoder is captured, if at least one traitor can be identified from it, a BDS is said to be traitor-tracing. If the data supplier can prevent subscribers from obtaining the contents without recalling their decoders, a BDS is said to be subscriber-excluding. In this paper, we propose an efficient BDS which is both subscriber-excluding and traitor-tracing. We use similar mathematics to a threshold cryptosystem. In the proposed BDS, the maximum number of excluded subscribers reaches the maximum number of traitors in a coalition for which at least one traitor can be identified. We prove that the proposed BDS is secure against ciphertext-only attack if and only if ElGamal cryptosystem is secure against the attack and the discrete logarithm problem is hard. The proposed BDS is the first one which satisfies all the following features: Both subscriber-excluding and traitor-tracing, identifying all the traitors, black box tracing and public key system.

This paper reviews analog-circuit researches in the 1990's especially from an academic-side point of view with the aim of pursuing what becomes important in the 21st century. To achieve this aim a large number of articles are surveyed and more than 200 are listed in References.

In this paper, we propose a mathematical model for one-dimensional finite linear cellular automata and show connections between our model and the classical one. We then demonstrate, through some examples, that our model is a useful tool for analyzing one-dimensional finite linear cellular automata. We also extend this model to the D-dimensional case and give an algebraic characterization for it.

Recently, antenna selection diversity has been widely used for hand-held phones to overcome a fading problem. A monopole antenna (MPA) and an inverted-F antenna (IFA) are the typical antennas used for this purpose. However, strong mutual coupling generally appears between these two antennas and often makes the diversity antenna design difficult. In particular, in the case that the MPA is unselected antenna the mutual coupling can be minimized using the open terminating impedance. On the other hand, in the case that the IFA is unselected antenna the terminating impedance, which can minimize the mutual coupling, has not been clarified. This paper presents a novel analytical method for optimizing the terminating impedance of the IFA. The method exploits the Z-matrix, and the final expression of the terminating impedance is expressed by self- and mutual-impedance. The numerical and experimental results confirm that the proposed optimization method is effective for minimizing the mutual coupling.

System capacity of a system consisting of N classes of users is characterized by N-vectors representing the number of users that can be accommodated under a specified BER (bit error rate) constraint in each class. In this paper, system capacity of the reverse link of a wireless multimedia CDMA system with processing gain control is analyzed in the asymptotic regime, when the processing gain G, for receivers with and without CCI cancellers. A new scheme for processing gain control with an optimized power allocation is proposed and its system capacity is compared with the conventional processing gain control scheme as well as the previously discussed power control scheme. It is shown that the proposed scheme has a certain advantage over other schemes.

This paper, for the first time, presents a provably secure signature scheme with message recovery based on the elliptic-curve discrete logarithm. The proposed scheme is proven to be secure in the strongest sense (i.e., existentially unforgeable against adaptively chosen message attacks) in the random oracle model under the discrete logarithm assumption. We give a concrete analysis of the security reduction. When practical hash functions are used in place of truly random functions, the proposed scheme is almost as efficient as the elliptic-curve version of the Schnorr signature scheme and existing schemes with message recovery such as the elliptic-curve version of the Nyberg-Rueppel and Miyaji schemes.

In this paper, we investigate the blocking characteristics of all-optical WDM (Wavelength-Division Multiplexing) networks under distributed wavelength assignment policies. For assigning wavelengths in a distributed manner, we consider two algorithms: random and locally-most-used algorithm. For a random wavelength assignment policy, we develop new blocking models of unidirectional/bidirectional ring networks based on the M/M/c/c queueing models under uniform/nonuniform traffic conditions. These models are shown to be more accurate than the previous blocking models since our approach considers the large traffic correlation among links in ring networks. We also analyze the blocking performance of the locally-most-used algorithm by comparing with that of the globally-most-used algorithm in fixed routing networks. We show that our analysis models match well with the simulation results in ring and mesh networks. Through the comparison with the previous centralized/distributed algorithms, it is demonstrated that the distributed locally-most-used algorithm is computationally efficient with good blocking performance.

In this paper, we propose a new kind of precoding method, modulated coded vector-TH precoding, to mitigate the channel intersymbol interference. The optimal design of the modulated code in vector TH precoding is presented. The coding gain of modulated coded vector TH precoding over conventional scalar TH precoding scheme is investigated in theory. Some simulation results are reported, which show that the proposed modulated coded vector TH scheme can provide a considerable coding gain compared with the conventional precoding techniques.

This paper deals with deadlock and fairness issues that may arise when network users request resources for guaranteed service with the resource reservation protocol (RSVP). A deadlock occurs when a request can only be satisfied if the resources reserved for another request are released, but the reserved resources are never released. The fairness issue occurs when some reservation requests may be satisfied but only after a very long wait. Our approach to these issues is based on our belief that a network should provide stable throughput and fairness whatever the behavior of the user. Our methods are unique in two respects. First, during the session setup phase, a node directly connected to the requesting users terminates the users' behavior and makes reservations fairly and efficiently in place of the users. Second, our three admission control methods allocate resources for each reservation request by considering not only the current residual bandwidth but also the properties of the requesting session; e.g., its weight (the number of resources it requires) or its age (how long it has been waiting for session setup). Our methods do not maximize the throughput since they always keep a certain amount of resources unreserved for fairness. From simulation results, however, they do provide quite fair behavior, and their throughput is stable regardless of the network size and the session holding time.