bluuebunny/crossref_metadata_2025_split huggingface dataset:
A standard cell global routing algorithm with net selection for over‐the‐cell routing
Authors: Koide Tetsushi , Suzuki Takeshi , Wakabayashi Shin'Ichi , Yoshida Noriyoshi 
Published: July 2007

AbstractIn the detailed routing for VLSI standard cell layout design, the over‐the‐cell channel routing, which utilizes the over‐the‐cell region as the routing region, has been proposed. In this design method, after determining the net assignment to each channel in the global routing step, the track assignment both in channel and on over‐the‐cell regions is performed by an over‐the‐cell channel router. However, conventional global routing algorithms do not assume over‐the‐cell channel routing but conventional channel routing. Therefore, the minimization of channel density does not always successfully lead to the minimization of the final channel height.This paper presents a new global routing method for standard cell layouts to determine global routes for each net in both channel and over‐the‐cell regions simultaneously. the standard cell layout design system GLORIA based on the proposed algorithm is developed, and the experimental results compared with the conventional global routing method that performs the over‐the‐cell channel routing after global‐routing with Timber Wolf‐SC4.2c are reported.Experimental results showed that the proposed routing algorithm can route about 18.4 percent fewer number of tracks than the conventional routing method, and the effectiveness of the proposed method is shown. the experimental results of applying the proposed method to the three‐layer routing layout model also are presented.
Two‐phase controlled switched‐capacitor impedance simulation circuits using one voltage follower
Authors: One Toshio 
Published: July 2007

AbstractSimulation cirucits for inductors and frequency dependent negative resistance (FDNR) based on switched capacitors (SCs) have been propsed. However, there has been no example reported in which a simple configuration of one voltage follower is used as an amplifier and a binary clock as the simplest control clock is used for operation. In the present research, it is pointed out that the conventional cirucit uses a delay circuit operated with a complicated clock. Such a configuration is simplified by using a fundamanetal delay circuit operated with a binary clock. It is shown that the simulation results obtained from the SC circuit analysis program SWITCAP agree with the theoretical results. Also shown are the experimental results with individual components and the effect of the parasitic capacitances.
A design method for parallel nonlinear adaptive digital digital filters using neural networks
Authors: Yahagi Takashi , Cao Jianting , Lu Jianming 
Published: July 2007

AbstractLinear adaptive digital filters are applied to various fields for their simplicity in the design and implementation. Considering many kinds of nonlinearities inherent to preactical systems, however, nonlinear adaptive filtering will be more desirable. In this paper, we present a design method for parallel nonlinear adpative digital filters using multilayer nonrecursive neural networks. Linear adaptive digital filters can be replaced by nonlinear adaptive digital filters with the advantage of obtaining better accuracy of estimation. Furthermore, the nonlinear adaptive digital filter is extended to parallel nonlinear adaptive digital filters which reduce the computations of each filtering system, especially when a high‐order nonlinear adaptive digital filter is necessary.
A formant frequency modification algorithm dealing with the pole interaction
Authors: Mizuno Hideyuki , Abe Masanobu 
Published: July 2007

AbstractWhen a formant is modified based on the pole of the AR model, a problem arises due to the interaction between the pole to be modified and other poles such as the apparent elimination of the formant, if the frequency of the considered pole simply is modified. to solve this problem, the method proposed in this paper uses the spectral intensity at the pole frequency as a new feature parameter and the spectral intensity at the pole after the frequency modification is corrected to the desired value by iterative processings.To examine the effectiveness of the proposed method, an experiment was conducted in which a phoneme in a word is replaced into the same phoneme in a different environment, and then the formant frequency is modified by the proposed method in order to restore the original speech. the speeches before and after the modification are compared in terms of the cepstral distance (CD) from the original speech, and it is verified that the proposed method is effective in the modification of the formant. an attempt is made to solve the formant discontinuity problem at the concatenation point in waveform based speech synthesis‐by‐rule and to modify the formant frequency accompanying the modification of the fundamental frequency using the proposed method. It was verified as a result of experiment that the speech after formant modification is better than the speech before modification, indicating that the proposed method is useful in improving the quality of the synthesized speech.
Design of linear‐phase M‐channel perfect reconstruction finite impulse response filter banks using lagrange‐newton method
Authors: Nagai Takayuki , Ikehara Masaaki 
Published: July 2007

AbstractFilter banks are separated roughly into paraunitary and nonparaunitary ones. Paraunitary filter banks are excellent and have several good characteristics, but it is difficult to design such a system. This research focuses on nonparaunitary filter banks and presents a design method for the linear‐phase (LP) M‐channel perfect reconstruction (PR) finite impulse response (FIR) filter banks. In this method, M‐2 analysis filters are arbitrarily designed and then the remaining ones are optimized using the Lagrange‐Newton method. Using the proposed method, PR filter banks with arbitrary order can be designed easily. Furthermore, the design method that considers the pairwise‐shift symmetry is shown and such a system is easy to design.
Development of a petri net‐based simulator for factory automation systems
Authors: Nagao Yoichi , Nakano Shinichi , Higuma Katsutoshi , Kumagai Sadatoshi 
Published: July 2007

AbstractThis paper presents K‐NET, a general‐purpose simulator for factory automation (FA) systems, that stimulates a system model based on Petri net. First, net elements for modeling, the model editing function, and the simulation function are explained; and then a planning system is described for automatic storage/retrieval systems that utilize the K‐NET simulation function, which automatically generates a simulation model, animates the system behavior, and evaluates system performance. Finally, a distributed simulator for large FA systems and an example application of the tool are described.
A new F‐H embedding algorithm for input encoding
Authors: Abe Motohisa , Ishimaru Masakatsu , Ariyoshi Hiromu , Shirakawa Isao 
Published: July 2007

AbstractThis paper presents a new encoding algorithm based on the face hypercube embedding for satisfying given input constraints. the algorithm works for a constraint relation matrix derived from the sets of the input symbols grouped for each output symbol independently and finds the encoding through row‐by‐row (group‐by‐group) cover assignment. A cover is found by the extension of a core cover generated from the magnitude estimations and adjacent relations of the currently known covers. Each cover is formed to be a single cube; and, if it is unsuccessful for specified code length, then the encoding length is extended. the experimental results indicate that this encoding technique has advantages over well‐known existing methods in the quality of encoding.
Vehicle behavior at a merging section of an automated transit system with a randomly varying arival rate
Authors: Hamamatsu Yoshio , Kikuchi Shinya 
Published: July 2007

AbstractThis paper considers the merging secton of the automated transit system which is a new transportation method. the behavior of the vehicle when the arrival rate of the vehicle of one of the lines varies is analyzed by the Markov chain technique. In past studies of the merging section, the case in which the arrival rate of the vehicle is kept constant in time is the one considered most of the time. When, however, some control is exerted on the vehicle traffic before the merging section, the arrival rate of the vehicle at the merging section will not be kept constant. This paper aims at a strategy conidering the arrival rate variation of the vehicle and analyzes the situation in the merging section when the ensemble of the arrival from one of the lines exhibits a variation of the state as a Markov chain. to analyze the vehicle behavior in such a model for the merging section, the state variable is defined and formulated considering the classes of the ensemble of the arriving vehicle. From the analysis results, the effect of the variation of the vehicle arrival rate on the queueing delay through the merging section is described.
Controlling chaotic discrete‐time systems via nonlinear feedback
Authors: Mori Hironobu , Ushio Toshimitsu , Kodama Shinzo 
Published: July 2007

AbstractRecently, occurrences of chaos have been reported in many engineering systems and most of these occurrences are unfavorable phenomena which used to be controlled. This paper proposes two methods for the stabilization of arbitrary unstable periodic orbits embedded in chaos attractors existing in nonlinear discrete‐time systems using nonlinear feedback. First, we proose a method based on a property of contracton mappings. Next, we propose another method using exact linearization via nonlinear feedback. In both methods, differentiability of the controlled systems is not required. Moreover, feedback ned not be reconstructed in target periodic orbits.
Theorem proving based on the partial instantiation technique
Authors: Yamamoto Masahito , Ohuchi Azuma , Ohyanagi Toshio 
Published: July 2007

AbstractFor studies toward the automated theorem proving, various methods and strategies have been presented based on the resolution principle proposed by Robinson in 1965. Most of the theorem‐proving systems at present are based on this resolution principle. In constrast to this, Jeroslow proposed the partial instantiation technique in 1988. the method proposed by Jeroslow, however, has a problem in that only the formula not containing function symbols is considered and the efficiency is low since the clause form is not assumed. the authors improved Jeroslow's method. A procedure was proposed where satisfiability is decided for the formula of the clause form not containing function sysmbols, and the effectiveness of the method is demonstrated.This paper extends the above procedure and proposes a theorem‐proving procedure so that the formula containing function symbols can be handled. A proof is given that the proposed procedure is complete. A comparison experiment is executed, and the effectiveness of the proposed procedure is investigated.
Maximally permissive controllers for controlled time petri nets
Authors: Takae Akiteru , Takai Shigemasa , Ushio Toshimitsu , Kumagai Sadatoshi , Kodama Shinzo 
Published: July 2007

AbstractStandard Petri nets are an untimed logical model. But timing information is important for real‐time control of discrete event systems. This paper studies state feedback control of concurrent discrete event systems modeled by controlled time Petri nets. It is assumed that a control specification is given in terms of markings. A maximal element of the set of controllers achieving a control specification is called a maximally permissive controller (MPC). In general, the MPC is not necessarily unique in controlled time Petri nets. In this paper, we present a necessary and sufficient condition for the unique existence of the maximally permissive controller. Then we derive a closed form expression of the unique MPC if it exists. Moreover, we synthesize a unique MPC for a simple manufacturing system.
An algorithm for a maximum clique of the intersection graph of isooriented rectangles on a cylinder
Authors: Kizu Takashi , Araki Toshiro , Kashiwabara Toshinobu 
Published: July 2007

AbstractA set ℱ of rectangles is considered which are placed on the surface of a right cylinder such that two of their sides are parallel to the axis of the cylinder. A graph G = (V, E) is called a rectangle‐on‐a‐cylinder‐intersection graph with a model ℱ, if the vertices of G can be put into a one‐to‐one correspondence with the rectangles in ℱ, such that two rectangles in ℱ have nonempty intersection if and only if two vertices corresponding to them are connected by an edge in G. In this paper, it is shown that given an ℱ, a maximum clique of the corresponding rectangle‐on‐a‐cylinder‐intersection graph can be obtained in polynomial time, by repeatedly using an algorithm for finding a maximum clique of a circular‐arc graph. Furthermore, an algorithm is constructed which, given a dynamic set C (initially empty) of circular arcs which changes as arcs are added to or deleted from C, finds a maximum clique of the circulararc graph corresponding to C in O(m(d + 1)) time every time C is changed (here m is the number of arcs and d is the number of arcs intersecting the added or deleted arc). It is also shown that, using this algorithm, an algorithm can be constructed for finding a maximum clique of a rectangle‐on‐a‐cylinder‐intersection graph in O(n(n + e)) time (n is the number of vertices and e is the number of edges).
An adaptive filter with adaptation to nonuniformly spaced samples
Authors: Sakai Miwa , Aizawa Kiyoharu , Hatori Mitsutoshi 
Published: July 2007

AbstractA novel adaptive filter is proposed that adapts to the sample spacing as well as to the tap weights. Although in adaptive digital processing, the tapped‐delay line usually has uniformly spaced taps, with the spacing equal to symbol period or a fraction of symbol period, an adaptive filter with a few taps should be adaptively arranged for nonuniform spacing for better convergence as the sampling timing varies. The conventional nonuniformly spaced filters are not adaptively changed or not arranged under the constraint of the acceptable meansquare error. In this paper, a least‐mean square (LMS)‐type algorithm is derived in which an adaptive filter adaptively changes the amount of delay, as well as the filter coefficients. The performance of the proposed algorithm is investigated by computer simulation.
A statistical decoding of simultaneous burst and random errors beyond the BCH bound using reed‐solomon codes
Authors: Horiguchi Toshio 
Published: July 2007

AbstractThis paper proposes a stochastic decoding method that can correct the composite errors beyond the BCH bound. It does this by tolerating that some of the composite errors cannot be corrected. Considering the case where the t‐error correcting Reed‐Solomon code with designed distance d = 2t+1 on GF(q) and code length n(⩽q‐1), it is shown that the proposed decoding method can correct the simultaneous composite errors composed of a single burst error of length v(<2t‐1) or less and t′(⩽t‐(1/2)v) or less random errors, with the probability not less than 1‐(n/(q‐1)2t‐v‐2t′).(1/t′). In other words, by setting v and t′ in the range tvt′<2t, the proposed method can correct the simultaneous composite errors beyond the BCH bound with the above probability. Then, a stochastic decoding system and a decoder circuit configuration are proposed based on the remainder decoding, and it is shown that a high‐speed stochastic decoder can be realized by a relatively small‐scale circuit when t′ is small (0⩽t′⩽2∼3).
Mathematical formulation of electron beam processing systems by stochastic variational inequalities
Authors: Ishikawa Masaaki 
Published: July 2007

AbstractThis paper is concerned with the mathematical formulation of electron beam processing systems. the mathematical model of stochastic electron beam processing systems proposed here takes randomness of material into consideration. In electron beam processing, the melting surface moves over time as a result of evaporation and melting material so that the melting surfaces become a so‐called free boundary. Therefore, the problem considered in this paper is among the free boundary problems, e.g., the Stefau problem. the difference between the problem proposed here and the Stefan one is that the term related to the intensity of the electron beam appears in the problem proposed by the author. For a system with a free boundary, variational inequality is an analytical method. Since this paper deals with the stochastic system with the free boundary, a system is formulated by the stochastic variational inequality of a new type, which is an extension to the stochastic system of a usual variational inequality. the uniqueness and existence properties of the solution of the stochastic variational inequality are also studied. the mathematical security of the model of the stochastic electron beam processing system is guaranteed.
Quantitative evaluation of trigger‐pulse reflected waves in supersonic extracorporeal shock‐wave lithotriptor
Authors: Nakamura Osamu , Morita Nagayoshi , Okazaki Kiyoshi 
Published: July 2007

AbstractAs one method to prevent the mis‐shot in the supersonic extracorporeal lithotriptor, there is a system in which the trigger pulse is emitted to ensure that a calculus exists in the focal region. This paper discusses the propagation of the trigger pulse within the body in this type of system, using the finite‐difference time‐domain method.In this paper, the scattering and reflection of the pulse is analyzed when a calculus is placed in the focal region of the ultrasonic propagation paths. Then, a calculus is assumed to be shifted gradually from the focal region and the change of the reflection is examined in relation to the operation of the trigger‐pulse systems.Finally, the case is considered where a calculus exists in the focal region and there exists a bony structure (called bone) near the pulse propagation paths. the propagation, scattering and reflection of the pulse is examined, and the effect of the position of the bone on the behavior of the trigger pulse is evaluated quantitatively and investigated.
Realization of two transfer functions with complex coefficients by a transfer function with hypercomplex coefficients
Authors: Ueda Kazuhiro , Takahashi Shin‐Ichi 
Published: July 2007

AbstractThis paper shows that two complex coefficient transfer functions can be realized by a single hypercomplex coefficient network, utilizing all four outputs of the hypercomplex network. the realization is considered for the case where the two arbitrary complex coefficient transfer functions do and do not have a common denominator. It is shown that the transfer functions can be realized by the hypercomplex coefficient network of the same order in the former case and by the hypercomplex coefficient network with the half‐order in the latter case. the realization of the transfer functions with the common denominator is interesting, but the general method to derive the transfer functions is not known.From such a viewpoint, this paper proposes the discrete‐type Kautz approximation with the positive frequency as the domain of approximation, including the optimal pole determination algorithm. By this approach, two complex coefficient transfer functions with ann‐th‐order common denominator are derived from the two 2n‐th‐order real or complex coefficient transfer functions. the method can be considered as one that simultaneously approximates the amplitude and the phase. the proposed approximation method is an approximation only for the positive frequency domain, and the property of the analytic signal that the negative frequency component is zero can be utilized. As a result, the method proposed in this paper has the advantages that the degree of freedom in the filter design is enhanced and the sampling frequency can be halved. In addition, the network structure can be simplified.
Two‐dimensional adaptive filters based on the one‐dimensional recursive least squares algorithm
Authors: Muneyasu Mitsuji , Uemoto Eiji , Hinamoto Takao 
Published: July 2007

AbstractThis paper proposes a method for realizing two‐dimensional (2‐D) adaptive filters by applying a one‐dimensional (1‐D) recursive least squares (RLS) algorithm. First, by applying a 1‐D RLS algorithm along horizontal and vertical directions, a novel 2‐D adaptive algorithm is developed. It is shown that the amount of calculations in the proposed algorithm is less than that in the existing 2‐D RLS algorithm. Moreover, the convergence properties of the proposed algorithm and its relation to the conventional 2‐D RLS algorithm are investigated. A method for accelerating the rate of convergence of the algorithm usinga prioriestimation error also is described.The proposed filter has good performance in nonstationary processes and the accuracy of convergence is better than that in the existing 2‐D adaptive filters based on the least mean square (LMS) algorithm. Therefore, the proposed filter is suitable for processing an image with strongly nonstationary characteristics. Finally, the utility of the proposed filter is illustrated by applying it to 2‐D system identification under a nonstationary environment as well as noise reduction of an image.
Proposal of a skill level index based on user's thinking time
Authors: Nakamura Yoshihiro , Kato Yasuyuki , Mitsunaga Yutaka 
Published: July 2007

AbstractThe time required to accomplish a task is the most common index of skill level. A learning curve that expresses the deductive process in relation to time needed is widely used. However, it does not always provide an accurate picture, because it cannot be used for a task that has an irregular form. and it cannot perform evaluations in real time during user operation. Moreover, because it is influenced by an error factor, it lacks precision. Studies have already been undertaken on a basic user adaptive interface. However, to increase its effectiveness and enable it to provide more intelligent support, it is necessary to consider the user's skill level. Thus, a skill level index is provided based on the user's thinking time. to put it more concretely, the authors looked at the time interval between one operation and the next. Using a statistical technique, we evaluated the skill level quantitatively. Experiments with test subjects showed that the proposed index coincides well with the subjectivity of the experimenter and the working time. the features of this index are that it does not depend directly on the content of the task, but on the user's cognitive performance. Therefore, this index can be used for a task with an irregular form and will provide real‐time evaluation by repeatedly gathering event data at regular intervals.