bluuebunny/crossref_metadata_2025_split huggingface dataset:
A note on performance improvement of Ziv‐Lempel code
Authors: Ise Koutarou , Tanaka Hatsukazu 
Published: July 2007

AbstractThe Ziv‐Lempel (ZL) algorithm is well known as an efficient universal source coding algorithm to encode a data string by replacing with codewords given by substrings in a fixed‐size buffer. However, the original ZL algorithm contains considerable redundancy on how to give a codeword for each substring because the same substring appears in some different places in the buffer.In this paper, a new algorithm to remove such redundancy is proposed to improve the coding efficiency for any kinds of strings. The algorithm requires search matched strings in the decoding process. A modified algorithm also is proposed to decode without searching matched strings.
A new cut for torsional mode quartz crystal resonators of tuning fork type
Authors: Kawashima Hirofumi , Nakazato Mitsuhiro 
Published: July 2007

AbstractThis paper proposes and describes a new cut torsional quartz resonator which is designated “TT‐Cut,” and clarifies its frequency characteristics, frequency temperature behavior, and electrical equivalent circuit parameters.First, in the analysis procedure, an equation of motion is derived from an energy method. Next, by solving the equation of motion under the boundary conditions of “free‐free bar” or “clamped‐free bar,” the frequency equations are derived as a function of thicknessz0, widthx0, and lengthy0.Furthermore, from the frequency equation a relationship of frequency constant (f.y0) versus thickness‐to‐width ratioRzx(=z0/x0) and a relationship between thickness‐to‐width ratioRzxand cut angles (ϕ, θ) where the first‐order temperature coefficient α reaches zero are derived theoretically. As a result, numerous relationships where α reaches zero are found to exist between thickness‐to‐width ratioRzxand cut angles (ϕ, θ). Especially, the second‐order temperature coefficient β has a small value of ‐1.16 × 10−8/°C2whose absolute value is approximately one‐third of the well‐known flexural mode quartz crystal resonator. The value of β then is‐compared with the measured data of ‐1.29 × 10−8/°C2, so that both results are found to agree sufficiently well.Finally, series resistanceR1and a quality factorQof a tuning‐fork‐type resonator are examined. Consequently, it is shown that a tuning‐fork‐type torsional quartz crystal resonator is obtained with a smallR1of 2.2 to 14.4 k° and a largeQvalue of 276, 000 to 378, 000 in frequency range of 385 to 444 kHz.
Knowledge‐based requirements specification and definition method for computer communication system design
Authors: Kinoshita Tetsuo , Sugawara Kenji , Shiratori Norio 
Published: July 2007

AbstractThe requirements specification and definition is one of the important and difficult tasks in the design and implementation of systems which realize various user requests.This paper proposes a knowledge‐based requirements specification and definition method for computer communication system design. In the proposed method, a framework for representing and utilizing various design knowledge of the requirements specification and definition is introduced based on a knowledge‐based design methodology for a computer communication system. According to the proposed method, the requirements specifications of logical functions of a computer communication system can be derived systematically from the users' requests and also represented in the formal descriptions called knowledge models of the requirements definition task.
Two‐dimensional adaptive state‐space filters using LMS method
Authors: Muneyasu Mitsuji , Hinamoto Takao 
Published: July 2007

AbstractThis paper considers the construction of two‐dimensional (2‐D) adaptive state‐space filters using the least mean squares (LMS) method. The approach is based on the Roesser local state‐space model. First, the relation between the coefficient sensitivities and the intermediate transfer functions is investigated. Then, after introducing new systems for generating the gradient vectors, an adaptive algorithm is developed using the LMS method.Next, a 2‐D adaptive state‐space filter with separable denominator is introduced to reduce the amount of computation in the adaptive process. Finally, a numerical example is given in which the 2‐D adaptive state‐space filters are used to design 2‐D digital filters in the spatial domain.
A layout description system using C language
Authors: Shigehiro Yuji , Shirakawa Isao , Harashima Katsumi , Kambe Takashi 
Published: July 2007

AbstractWith the rapid progress of VLSI microfabrication technology, the functional cell library must be updated frequently. Then it is important to develop a functional cell generation technique. For this purpose, the study of technique is considered interesting, which represents the layout pattern efficiently and independently of the process technology, using a language.This paper discusses the layout language based on the general‐purpose C language and the processing system. The layout pattern is described using C language and newly defined functions for layout description. Then the layout data are generated automatically from the description.First, the assumed layout pattern structure is considered. Then the proposed layout description technique, as well as the realization of the processing system, are discussed. Finally, the processing system actually is constructed and it is demonstrated that the layout pattern is generated automatically from the layout description.
Digital filters with hypercomplex coefficients
Authors: Ueda Kazuhiro , Takahashi Shin‐Ichi 
Published: July 2007

AbstractThis paper considers digital filters with hyper‐complex coefficients. Filters of this type can reduce the order of filters to one‐fourth the one with real coefficients. It is reported that the first‐order digital filter with hypercomplex coefficients can realize the fourth‐order digital filter with real coefficients which can be expressed by a second‐order all‐pass filter with complex coefficients.This paper considers also generalization including the foregoing special case and shows that the first‐order digital filter with hypercomplex coefficients can realize an arbitrary‐order digital filter with real coefficients less than 4.Arbitrary higher‐order digital filter with real coefficients can be realized by parallel connection or cascade connection of first‐order digital filters with hypercomplex coefficients. This paper considers the following three different realizations: (a) realization by parallel connection; (b) realization by cascade connection of real part; and (c) realization by cascade connection. We find that case (b) is the most low sensitive. Finally, stability criteria of hypercomplex digital filters of first‐order are suggested.
Perception of depth movement and temporal frequency characteristics of stereoscopic vision
Authors: Yano Sumio , Mitsuhashi Tetsuo 
Published: July 2007

AbstractThe repetition frequency and the maximum disparity in stereoscopic vision where depth movement is perceived are determined using a static random dot stereogram (SRDS). Furthermore, the temporal frequency characteristics of the maximum fusible disparity are determined using a dynamic random dot stereogram (DRDS). The results show that in both cases, as the frequency of depth movement increases, the maximum fusible disparity decreases. For sine waves above 15 Hz and square waves above 7.5 Hz, binocular fusion is not possible when the target is the SRDS. For both sine and square waves above 7.5 Hz, binocular fusion is not possible when the target is the DRDS. In both cases, binocular fusion is only possible at lower frequencies. It is clear that compared to SRDS, the maximum fusible disparity is larger for DRDS when the center of motion is set on the plane of the screen and becomes smaller when the center of depth motion is shifted off the screen as the shift of the center of motion increases or fusion becomes impossible in the high frequency range.
A fast learning algorithm for neural networks and its applications to adaptive equalizers
Authors: Miyajima Teruyuki , Hasegawa Takaaki , Haneishi Misao 
Published: July 2007

AbstractThis paper proposes a fast learning algorithm of neural networks and evaluates the performances of adaptive equalizers using neural networks trained by the proposed algorithm in a frequency‐selective fading channel. The backpropagation (BP) algorithm which is used widely to train neural networks has a slow convergence rate because it is based on the gradient descent method.This paper presents a fast learning algorithm using the recursive least squares (RLS) algorithm which has a fast convergence rate as an adaptive algorithm for adaptive linear filters. In the proposed algorithm, the sum of the squared error between the actual total input and the desired total input is used as the cost function to apply the RLS algorithm. A simulation result on the exclusive‐OR problem indicates that the proposed algorithm is about 8.8 times faster than the BP for the number of iterations required to converge.Recently, there has been interest in adaptive equalizers as an application field of neural networks. However, the performance of an adaptive equalizer using a neural network in a frequency‐selective fading channel which is observed in land mobile communications has never been evaluated. Therefore, in this paper, the performances of adaptive equalizers using neural networks trained by the proposed algorithm in a frequency‐selective fading channel are evaluated. Especially, an adaptive equalizer using the selectively unsupervised learning neural network proposed by the authors is considered. The adaptive equalizer can reject the false learning by carrying out learning selectively. It is shown that the adaptive equalizer is superior to the conventional one and the one using the conventional neural network.
Measurement and estimation of system nonlinearity via a neural network
Authors: Yana Kazuo , Yoshida Hisashi , Komai Masanori 
Published: July 2007

AbstractThis paper defines the degree of nonlinearity as a measure for the nonlinearity of the system. A method for estimating the nonlinearity is proposed based on the input and the output time‐series signals under the actual condition that the additive observation noise is included. The degree of nonlinearity of the system takes a value between 0 and 1. It approaches 1 when the part of the variational power that cannot be represented by the linear combination of the input increases in the output variation depending on 0‐input in the linear system.A multilayer perception is introduced as a parametric function which represents the wide class of nonlinear functions needed in the estimation. An example is shown of the family of memoryless and nonlinear systems where the degree of nonlinearity changes from 0 to 1 by the change of the system parameter. An example also is shown of the system with a finite memory having a degree of nonlinearity of 1.By a computer simulation, the validity of the nonlinearity estimation proposed in this paper is demonstrated. The method will be applied effectively to the modeling of the system based on the observed input and output signals.
Pupil size and eeg affected by visual stimuli
Authors: Nagatsuka Mamoru , Shimizu Yasutaka 
Published: July 2007

AbstractThe purpose of this paper is to study the objective evaluation of educational video software, etc., by biological data. A visual stimulus is presented using CRT, the pupil size and EEG are examined simultaneously, and the changes are analyzed. In such a simultaneous measurement, the interference of CRT noise to EEG measurement must be avoided. A special shielding room is designed using a transparent shielding glass so that the stimulus can be presented to a subject from the outside. The effectiveness of the shielding is verified. The effect of attaching the pupil‐size measuring instrument exerted on EEG measurement is examined. A still‐picture pattern with semantics is presented to the subject while adjusting the average brightness to a constant value, and the pupil size and EEG are measured simultaneously. A negative correlation is observed between the EEG power in the 9.0‐ to 11.0‐Hz band and the pupil size. It is seen also that, when a pattern that strongly interests the subject is presented, the pupil size becomes large and the band power becomes low. Thus, it is demonstrated that the difference of the content of the presented pattern can be evaluated more clearly by the simultaneous measurement.
Probability distribution with respect to expansion or contraction of image size
Authors: Iijima Taizo 
Published: July 2007

AbstractOften, in handwriting a character, a natural expansion or contraction occurs even if the writer intends to write the character in a specified size.This paper considers the expansion‐contraction phenomenon which appears statistically in drawing a figure in general. A theoretical investigation is presented from the theory of probability, and the shape of the probability distribution governing the phenomenon is analyzed mathematically. The approach also gives an answer from the viewpoint of the theory of probability to the problem where the length is expanded or contracted unintentionally, even if a constant length is intended.This paper shows a typical mathematical approach in which the determination of the shape of the probability density function is reduced to the solution of the special functional equation. It is considered to be interesting also from the viewpoint of the theory.
Bifurcation of heteroclinic orbits in a circuit containing a josephson junction element
Authors: Ueta Tetsushi , Kawakami Hiroshi 
Published: July 2007

AbstractThe circuit equation of the circuit containing a Josephson junction and the equation of motion of a pendulum in which an elastic restoring force is applied in the direction of rotation are described in terms of a second‐order ordinary differential equation containing the sum of a trigonometric term on the state and a linear term. In such a dynamic system, the number of saddles and sinks changes according to the parameter values and no periodicity exists with respect to the location of the saddles and sinks, thus analysis is difficult.In this paper, a circuit containing a Josephson junction is chosen as an example of such a dynamic system. Classification by the tangent bifurcation of the saddles and sinks and the results of the analysis based on the heteroclinic orbits on the phase plane are presented. The heteroclinic orbit presents a global bifurcation on the phase plane due to its structural instability. The parameters generated by this orbit are used as the values for the bifurcation, and the bifurcation set was derived on the parameter plane. As a result, the unique linking number is defined for a particular parameter region surrounded by the bifurcation curve. This value can be used as a guideline for rotation of the orbit on the phase plane. Further, by combining it with the bifurcation ensemble, a classification of the stable sinks in the basin is made possible.
Selection of fuzzy if‐then rules by a genetic method
Authors: Ishibuchi Hisao , Nozaki Ken , Yamamoto Naohisa , Tanaka Hideo 
Published: July 2007

AbstractThis paper proposes a genetic algorithm‐based method for constructing a fuzzy classification system with fuzzy if‐then rules. In the proposed method, a rule selection problem for constructing a compact fuzzy system with high classification power is formulated as a combinatorial optimization problem with two objectives: to maximize the classification rate and to minimize the number of rules. Then a method of implementing genetic algorithms is proposed for the application to this problem and its effectiveness is demonstrated by computer simulations. The implementation of genetic algorithms in this paper employs an approach where a set of fuzzy if‐then rules is coded as a single individual.
Fundamental theory of natural observation transformation
Authors: Iijima Taizo 
Published: July 2007

AbstractWith regard to the theory of natural observation proposed as a new method of waveform analysis and although papers by the author have already been published over the last few years, this paper attempts a generalization based on the theory. As a result, the theory of natural observation can largely be divided into the neighboring type and the equilibrium type. Further, it was clarified that the previous theories belong to the neighboring type.In the treatment of acoustic vibration waveforms such as voice, the hitherto not discussed equilibrium type is desirable. Also, based on the forementioned theories, the general form of natural observation transformation is proposed anew as a substitute for Fourier transformation and, in particular, the standard form thought to be useful hereafter is shown concretely.
Origin of the natural observation theory of standard form
Authors: Iijima Taizo 
Published: July 2007

AbstractThe theory of natural observation has been proposed as a new method of analysis to replace the Fourier analysis method. It was systematized as a theory with two major types—the neighboring type and the equilibrium type. Especially, although the nucleus of the theory is of standard form, the description with regard to the starting point of the theory in the past has not always been plain and comprehensible.This paper is a radical improvement in this regard and was written to clarify the origin of the theoretical development. Although the previously published theories are not completely revised, this paper is considered significant from the viewpoint of clarification of the base of the theoretical development.
Spatio‐temporal analysis of eye movement patterns based on the maximum entropy method and the higher moment features
Authors: Sakaino Hidetomo , Tetsutani Nobuji , Kishino Fumio 
Published: July 2007

AbstractThis paper considers the eye movement pattern when observing the eye mark pattern. The spatio‐temporal method of spectrum analysis based on the maximum entropy is proposed as well as the statistical method of analysis combining the higher‐order moment features to extract the features from the analyzed spectrum pattern. The similarity pattern is used as the eye mark pattern, where segment, polygon, and circle are used as the primitive patterns. The eye mark pattern is projected on a large screen with the view angle of 80 deg. The density of the pattern is approximately 1.04 and 0.35 deg in terms of the view angle. The spectrum pattern of the movement is analyzed from the two standpoints of time and frequency. It is seen as a result that the number of angles, shape, and pattern density are reflected more strongly on the durations of the gaze and saccade movement rather than their frequencies in the observation period. This result suggests that the image features will be estimated from the movement pattern.
Montgomery modular‐multiplication method and systolic arrays suitable for modular exponentiation
Authors: Iwamura Keiichi , Matsumoto Tsutomu , Imai Hideki 
Published: July 2007

AbstractThe Montgomery method is known as a method to execute modular multiplications without using divisions, and several systolic arrays have been proposed for execution of the Montgomery method. A problem in the Montgomery method is that the number of output bits may exceed the number of input bits. In the past implementations, the size of the output must be examined and corrected each time the method is executed, which is an obstacle in improving the efficiency.From such a viewpoint, this paper derives the general condition so that the size of the output need not be examined each time the Montgomery method is executed and proposes two types of systolic arrays that execute the Montgomery method under that condition. These arrays are more efficient than the systolic array proposed previously by the authors for modular multiplications. The method is effective and practical for VLSI implementation such as on a chip.
Gesture description and structure of a dictionary for intelligent communication of sign language images
Authors: Xu Jun , Tanahashi Shin , Sakamoto Yuji , Aoki Yoshinao 
Published: July 2007

AbstractIn the intelligent transmission of the sign language image based on the semantic information, one possible method is to transform the semantic information on the receiving side into the motion parameters of the upper extremities and to synthesize the animation image of the sign language. For this purpose, the word dictionary to describe the motion of the upper limb corresponding to the semantic information must be constructed. A problem then is that the human upper limb has a large degree of freedom. It is difficult to control skillfully the posture of the upper limb using the motion parameters for the joint movements. Thus, the complex motion is realized by combining the posture and motion of the upper limb, corresponding to the sign language.This paper proposes a method in which the shape of the hand to be used in the sign language is described by a table and the motion of the upper limb is described and represented by the motion features of the gesture based on the joint angle model. The method to construct two kinds of word dictionaries, called “representative dictionary” and “realizing dictionary,” are proposed to generate the animation image for the sign language based on the semantic information. The representative dictionary gives the basic motion of the sign language. The realizing dictionary describes the control parameters such as the iteration and the speed of motion. The word in sign language is realized by adding the realizing form to the representative form. In the proposed method, the description of the word in the signal language is simplified, which makes it easy to control the upper limb posture as well as to iterate or emphasize the motion, using the method proposed in this paper, a word dictionary is constructed to describe the gesture of the sign language. A system is discussed in detail which transforms the input sentence in Japanese into the animation image.
Synthesis of decentralized state feedbacks for large‐scale discrete event systems
Authors: Takai Shigemasa , Kodama Shinzo , Ushio Toshimitsu 
Published: July 2007

AbstractThis paper considers the large‐scale discrete event system which is composed of multiple concurrently operating subsystems. The decentralized state feedback control is discussed for the case where the control specifications are given by predicates concerning the whole system. First, a necessary and sufficient condition is shown for a predicate which is obtained by a global state feedback to be obtained also by a decentralized state feedback. However, it should be noted that, in general, there exists more than one decentralized state feedback that can achieve the global predicate.From such a viewpoint, the maximally and minimally permissive decentralized feedbacks are defined and investigated. It is shown that there always exists the minimally permissive decentralized feedback, and its construction method is presented. Also, it is shown that, although the maximally permissive decentralized feedback does not, in general, exist, it can be obtained in the case that local state feedbacks are constructed according to a specified order. The construction method for that case is shown.