bluuebunny/crossref_metadata_2025_split huggingface dataset:
2‐D cutting‐stock algorithms based on local optimization
Authors: Sakamoto Toyokazu 
Published: July 2007

AbstractThis paper proposes the two‐dimensional (2‐D) cutting‐stock algorithm based on the local optimization. First, it is intended to eliminate the combinational process for the rectangular parts in the traditional system. The search operation is defined as the one‐to‐one mapping of the rectangular parts to the partial rectangular regions generated by the divide operation. A stack is used to store the data for the partial rectangular regions, and the merge operation is introduced as a new concept of operation in the stack. The algorithm is constructed recursively using the following four operations, i.e., search, divide, merge, and stack. Through an application example, it is verified that the proposed algorithm can realize nearly the same layout efficiency as the traditional method by the dynamic programming.
Inverse gaussian distribution and its application
Authors: Sato Shunsuke , Inoue Junko 
Published: July 2007

AbstractThe inverse Gaussian distribution is related closely to the Gaussian distribution as is suggested by its name. It is used not only in mathematical statistics but also in various fields such as engineering to describe various phenomena and to make quantitative analysis.Schrödinger derived the cumulant generating function for the first‐passage time of the Brownian motion with a drift. Then Tweedie extended Schrödinger's result and found that the cumulant‐generating function for the time to travel for a unit distance and the cumulant‐generating function for the distance traveled in the unit time are in the relation of the inverse function. Tweedie found also that the same relations exist between the binomial distribution and the negative binomial distribution as well as between Poisson distribution and gamma distribution. He called one of those the inverse of the other. The study of the inverse Gaussian distribution was developed further by Wasan, Johnson and Kotz; Folks and Chhikara; et al.This paper discusses the first‐passage time distribution of the Wiener process as the origin of the inverse Gaussian distribution, the inverse Gaussian distribution itself and its properties, the generalized inverse distribution, and the application of the inverse Gaussian distribution.
Synthesis of “narrow‐band” random moving image via computer
Authors: Takahashi Nobuyuki , Tanaka Tetsuya , Ogura Hisanao 
Published: July 2007

AbstractThis paper presents a simple generating algorithm for a moving random image by generalizing the algorithm for a stationary random image in a previous work. Although the algorithm is applicable to a more general case, special emphasis is placed on the “narrow‐band” random image with two or more spectral peaks which models a rough sea surface with strong periodic correlation. Such a “narrow‐band” image can be given as the real or imaginary part of a complex‐valued random image described by a noncausal model.A moving random image which is a spatio‐temporal random field and a moving image drifting in a certain direction can be generated by a modified simple algorithm; and several examples are given. Generation of such a stationary or moving random image with given statistical properties is useful in the study of various image processing.
A parametric loudspeaker—applied examples
Authors: Aoki Kenichi , Kamakura Tomoo , Kumamoto Yoshiro 
Published: July 2007

AbstractA parametric loudspeaker using the self‐demodulation of finite‐amplitude ultrasound has a sharper directivity than a conventional loudspeaker of the same aperture size. This is because of the formation of the end‐fire array with virtual sound sources which are generated in the ultrasound beam. In general, when the aperture becomes smaller, the difference in directivity appears clearly.This article describes a theoretical prediction of the optimum frequency of primary ultrasound waves to develop a transmitter with small aperture and compares the theory and experiment using an 11‐cm diameter parametric loudspeaker. The possibility of practical use for guidance equipment such as an audible pedestrian signal also is discussed. Furthermore, using large‐aperture parametric loudspeakers, an experiment is carried out in a reverberant tunnel to confirm the effectiveness in the improvement of speech articulation.
Reduction of deviation of frequency characteristics of saw filters by mechanical polishing of zno film surface
Authors: Kadota Michio , Kondoh Chikashi , Chubachi Noriyoshi 
Published: July 2007

AbstractIt was found that the surface acoustic wave (SAW) amplitudes in SAW filters made of ZnO films vary from filter to filter even when the center frequencies are the same and the deviation of amplitudes must be reduced. It was found also that the frequency and amplitude characteristics could be improved by mirror polishing of the ZnO film surface.In an SAW filter with a ZnO/interdigital transducer (IDT)/glass substrate structure, periodic convex areas due to the thickness of the finger electrode of IDT and fine roughness were present on the device surface. As a result of investigating the influence of the surface structure on the amplitude deviation, it was found that the convex areas did not influence the electromechanical coupling coefficient; but they reduced the acoustic velocity of SAW. In addition, it was clarified that the convex areas due to the finger electrode and fine roughness on the ZnO surface caused deviations in the acoustic velocity of SAW and reflections of SAW, causing a deviation in the amplitude characteristics.
Two‐dimensional line spectrum estimation by polar coordinate ar models
Authors: Sakurai Manabu , Hamada Nozomu 
Published: July 2007

AbstractIn this paper, a spectrum estimation method is proposed which is based on a two‐dimensional autoregressive (AR) model with polar coordinate coefficient arrangement. When the signal is given in terms of an orthogonal coordinate system, such a coordinate system is naturally used for linear prediction in a conventional AR estimation method. The support of the estimation coefficients and the peak shape of the corresponding estimation spectrum are known to be related by a certain rule.By using an AR model in which the coordinate arrangement of the linear prediction is in a polar coordinate, the rotation of the coordinate region keeps an AR model in the same polar coordinate form. Hence, it is possible to determine the relative positional relationship between the estimated spectrum shape and the coefficient mask. It is shown that the present method can estimate the spectrum with a high resolution by using this relationship and avoiding the interference between the spectral peaks.
A method for analog circuit design that stores and reuses design procedures
Authors: Morie Takashi , Onodera Hidetoshi , Tamaru Keikichi 
Published: July 2007

AbstractThis paper proposes a new design methodology that improves the efficiency of analog circuit design. In the conventional design environment, designers try to enhance design productivity by storing designed circuits in a library for future reuse. However, a fixed circuit stored in a library is optimized to a particular set of performance specifications; and, hence, its reusability is low.By contrast, the proposed methodology stores not only designed results but also design methods that show how to design circuits. When different sets of specifications are required, circuits are designed automatically based on the stored design methods, which improves design efficiency.To evaluate the proposed design methodology, a method is devised that automatically stores a design procedure from the design process of a human designer and reuses it for circuit analysis. A prototype design system that realizes it is implemented. Experimental results on the design of an operational amplifier show the effectiveness of the proposed methodology.
Computer generation of lyapunov functions and estimation of a stability region
Authors: Ohta Yuzo , Nonomura Tsuyoshi , Imanishi Hiroshi , Haneda Hiromasa 
Published: July 2007

AbstractThe Lyapunov method is one of the most powerful methods for analysis of stability. However, from the practical viewpoint, there is no method to construct a Lyapunov function applicable to systems in general.This paper presents the Lyapunov function that is determined by a polytope and which is suitable for computer generation of Lyapunov functions since neither a special form of function nor the number of parameters to be chosen need be given in advance. Moreover, the estimate of the stability region can easily be improved since the modification of Lyapunov function is that of the corresponding polytope.In this paper, the notion of the traditional sector condition is generalized so that a given function is bounded by using the convex combination of a set of piecewise‐linear functions. Using this generalized sector condition, improved stability conditions are derived and it is applied to construct the Lyapunov function.
Design of digital allpass networks based on the eigenvalue problem
Authors: Zhang Xi , Iwakura Hiroshi 
Published: July 2007

AbstractThis paper presents a new method of the phase design for the digital allpass network utilizing the eigenvalue problem. The proposed design method considers the phase error between the phase response of the allpass network to be realized and the ideal phase response. The design problem is formulated as an eigenvalue problem based on the Remez algorithm. By calculating the eigenvector corresponding to the maximum eigenvalue, the filter coefficients are determined and the optimal approximate solution is obtained by iterative calculation.In the design method, the eigenvector corresponding to the maximum eigenvalue is calculated to determine the filter coefficients so that the phase error is minimized. Consequently, the convergence of the design algorithm is guaranteed. Usually, the optimal approximate solution is obtained by several times of iterations. The error‐ratio of the phase characteristics can be set arbitrarily, and the stability of the filter is ensured.Finally, the method is extended to the phase design for the digital allpass network with complex coefficients, several design examples are shown, and the usefulness of the proposed design method is demonstrated.
Synthesis of switched‐capacitor higher‐order immittance simulation circuits
Authors: Ono Toshio 
Published: July 2007

AbstractElement level simulation using a switched capacitor (SC) have been employed mainly for inductance simulation and there have been quite a few reports on the higher‐order immittance simulation which is a current research topic of analog filters.This paper proposes two types of SC circuits—ungrounded frequency‐dependent negative resistance (FDNR) and frequency‐dependent negative inductance (FDNL)—synthesized by bilinear transformation and the simulation results by the SC circuit analysis program (SWITCAP) are compared with the theoretical values. Moreover, the experimental results on the discrete components are shown which agree well with theoretical values.The circuits use unity gain buffers (UGBs) as active devices due to their simple synthesis, and they are controlled by a two‐phase clock. Moreover, the parasitic capacitors which are derived from bottom plates of an integrated capacitor have no effect on the performance except for one capacitor which determines the element values.
Design of 3‐D separable‐denominator digital filters using minimal decomposition and balanced realization
Authors: Hinamoto Takao , Harada Ken‐Ichi 
Published: July 2007

AbstractBased on a concept of minimal decomposition and balanced model reduction, a technique is developed for designing three‐dimensional (3‐D) separable‐denominator digital filters in the spatial domain. This is done by decomposing a desired 3‐D FIR filter into three parts and by representing it by a cascade connection of three 1‐D filters. The minimal decomposition treated here can be viewed as an extension of that in the 2‐D separable‐denominator case. A numerical example also is given to illustrate the utility of the proposed technique. The amount of calculation required here is relatively small and the stability of the resulting filter is always guaranteed.
Training method of the excitation codebooks for code‐excited linear prediction
Authors: Moriya Takehiro , Miki Satoshi , Ohmuro Hitoshi , Mano Kazunori 
Published: July 2007

AbstractThis paper considers the codebook for low bit‐rate speech coding by code‐excited linear prediction (CELP) and the mapping table for the channel code. It also proposes an optimization procedure for sequential training based on the structured excitation codebook. In the discussions of structurization of the codebook, the conjugate structure to represent the output by the sum of two vectors, the pitch synchronized processing, rotating use of the codebook, the time‐domain sloped gain, and the integrated mapping to the channel code are considered. The distortion measure used in the training is the same closed‐loop measure as is used in the coding. In other words, the distortion between the input speech and the synthesized speech at the perceptually weighted filter output is minimized. By training the codebook, the SNR of the coded speech is improved by approximately 1 dB. The improvement in speech quality is also verified. It is also verified that the robustness against bit error can be improved by the training of the mapping table to the channel code, as well as by training based on the distortion measure considering bit error.
Theory of cosine‐modulated two‐dimensional perfect reconstruction filter banks
Authors: Ikehara Masaaki 
Published: July 2007

AbstractThis paper considers a cosine‐modulated, two‐dimensional (2‐D) perfect reconstruction (PR) filter banks theory. First, a 2‐D digital filter with half‐pass‐band obtained by the sampling matrix had to be designed. Next, 2‐D analysis filter banks are realized by cosine‐modulating this prototype 2‐D digital filter so that 2‐D analyzed signals become real. It is shown that the modulation in the 2‐D frequency plane is equivalent to 1‐D modulation. A necessary and sufficient condition for 2‐D perfect reconstruction filter banks is derived. If the polyphase filter pairs of the prototype filter doubly complement, the resulting 2‐D filter bank satisfies the condition of perfect reconstruction.
A recursive orthogonal wavelet device
Authors: Yasuoka Hiromichi , Ikehara Masaaki , Isobe Hiroyuki 
Published: July 2007

AbstractA design for a one‐dimensional (1‐D), 2‐D recursive orthogonal wavelet consisting of a parallel connection of a delay and allpass network is presented. There have been some methods to obtain wavelet functions from perfect reconstruction filter banks following an investigation by Mallat of the relation between wavelet transform and filter banks. These methods are based mostly on an FIR filter. A method based on IIR filters has never been investigated. IIR digital filter has fewer orders than FIR digital filters to realize the same specification and satisfies the orthogonal condition of the orthogonal wavelet by using both parallel connection of some delays and an allpass filter. Furthermore, a maximum number of zeros are placed at aliasing frequencies in the lowpass filter as a way of obtaining the regularity of the wavelet. Finally, some design samples of discrete scaling and wavelet functions are presented.
A new method for breaking the Lu‐Lee cryptosystem
Authors: Hayashi Akira , Shimizu Hideo 
Published: July 2007

AbstractThe authors present a method to break the Lu‐Lee (LL) cryptosystem, whose security is based on the difficulty of factoring the product of large primes. Previously, other methods of attacking the LL cryptosystem have been proposed, but the new method proposed here is different from them. In the present method, the computation required is polynomial‐time and computer experiments make it clear that all the cipher text can be broken with high speed. In this method, the authors construct simultaneous congruences from the encryption congruence and then transform these into simultaneous equations, whose solution gives the original plain text. The authors do require a condition for the transformation into equations, but it is satisfied in almost all cases; so the probability of success of the attack can be considered to be high.
The relation between neighboring type and equilibrium type in the natural observation theory
Authors: Iijima Taizo 
Published: July 2007

AbstractThe theory of natural observation, an approach analysis which replaces Fourier analysis, has been divided into two types: the neighboring type; and the equilibrium type. These types have theoretical systems that are derived from different starting points; theoretically, they have mutual close relations. The purpose of this paper is to elucidate the close relations between these two types. First, it is shown that the set of fundamental observed values defined for one side of types is uniquely derivable from the other, and also that the mathematical form of the derivation maintains duality.Next, an infinite number of invariant determinants are constructed from the set of fundamental observed values, and they are proved to be independent of type.
Synthesis of low‐sensitivity leapfrog switched capacitor filters (SCFs)
Authors: Ishikawa Masayuki , Fujii Nobuo 
Published: July 2007

AbstractThis paper proposes multiinput switched capacitor (SC) integrators required for realization of leapfrog SC filters exhibiting zero sensitivity at matching points. the signal flow graph‐based simulation of an LC ladder filter built of proposed integrators shows that the filter exhibits zero sensitivity. Integrators are driven by a two‐phase clock and, under certain conditions, are insensitive to parasitic capacitance. Furthermore, total filter capacitance generally is kept small.Computer simulation of lowpass and bandpass filters constructed of the proposed integrators illustrates their comparatively low sensitivity.
Global optimization method using chaos in dissipative system
Authors: Fujita Tokumitu , Yasuda Keiichiro , Yokoyama Ryuichi 
Published: July 2007

AbstractMost of the actual optimization problems are nonlinear and have many peaks (nonconvex). With the widespread use of the high‐speed and large‐capacity computers as the background, it has recently been felt highly necessary to derive the global optimal solution for the optimization problem which is nonlinear and has multiple peaks. It is one of the most important topics of research in the field of optimization.The major global optimization method developed until now can be divided into the trajectory method, the function transformation method, and the simulated annealing method.This paper proposes a new approach which is totally different from the forementioned conventional methods, i.e., the global optimization method for the unconstrained nonlinear optimization problem where chaos is introduced. the proposed method is based on the dissipative system where the inertia term and the nonlinear damping term are added to the conventional gradient method.By appropriately adjusting the characteristics of the nonlinear damping term, the generation of chaos can itself be controlled. Then, by overriding the barrier of the energy function between the local minima, the process converges to the global optimal solution.Finally, the proposed method is applied to the typical multipeaked nonlinear optimization problem with two and ten variables and it is shown that the global optimal solution can be derived by adequately adjusting the parameter of the nonlinear damping term.
Features of a two‐dimensional random field: Number of degrees of freedom, correlation areas and correlation lengths
Authors: Kikkawa Sho , Sakamoto Masato , Kobayashi Naoya 
Published: July 2007

AbstractOne of the important features that characterize the physical random field or the image texture is Taylor's correlation length. However, there has not been presented a clear‐cut theory as to the foundation of the correlation length from the viewpoint of probability theory or statistical theory. Another aspect is that the feature is one‐dimensional, and, therefore, the application to the random field is limited to the isotropic random field.This paper defines thenth order statistical number of degrees of freedom as the equivalent number of uncorrelated points in the square finite region in the homogeneous random field. From the definition, the correlation area and the correlation length are derived. the correlation area is referred to as the average area of the region statistically affected by an arbitrary point on a two‐dimensional field. the correlation length represents the effective distance between adjacent independent or uncorrelated points on the line parallel to thex‐ ory‐axis. the first‐order correlation length is the same as the conventional Taylor correlation length. the first‐order correlation area is a natural extension of Taylor's correlation length to the two‐dimensional random field. the correlation length along the principal axis, which is independent of the definition of the coordinate axis, is also derived. Those features are based on the theory of statistics and are expected to be useful for the analysis of the actual random physical field and the texture analysis of the image.
Design of two‐dimensional maximally flat diamond‐shaped half‐band finite impulse response filters with rectangular supports of impulse response
Authors: Inui Kiwamu , Yoshida Toshiyuki , Nishihara Akinori , Fujii Nobuo 
Published: July 2007

AbstractTwo‐dimensional (2‐D) diamond‐shaped filters are important filters with many applications and are known to be designed and implemented efficiently as 2‐D half‐band filters. On the other hand, filters with different number of taps in both directions are often suitable for a specific application rather than filters with equal number of taps.This paper proposes a design method for 2‐D maximally flat diamond‐shaped filters with rectangular support of impulse response. First, the maximally flat conditions at the origin are considered together with equations which make the filter approximately diamond‐shaped. Then, by combining the derived conditions to form a system of linear equations with respect to the independent filter coefficients, designs for the difference in the number of taps 2, 4, and 6 are demonstrated. Finally, together with giving several design examples, comparison with other design methods are made and the usefulness of the suggested design method is verified.
Altitude prediction by natural spline tracker
Authors: Shirakawa Masayuki 
Published: July 2007

AbstractIn airborne collision avoidance system (ACAS) and air traffic control radar beacon system, altitude tracking filter is used for altitude prediction. These trackers are known to have large error when the data are lost. This paper presents the new prediction filter to improve the accuracy in this coast situation. the extrapolation of natural spline function is used for this purpose. the simulation shows this tracking filter has better performance than conventional filter.