bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new sound image broadening control system using a correlation coefficient variation method
Authors: Kurozumi Kohichi , Ohgushi Kengo 
Published: July 2007

AbstractAfter examining the conventional quasistereophonic system, this paper presents the bandwidth division system and the phase shift system as two new types of quasistereophonic systems. These two new systems are based on the understanding that “if the correlation coefficient of a two‐channel acoustic signal is zero (and independent), the sensation of acoustic spreading is a maximum.” It is shown that the correlation coefficient of the two‐channel acoustic signals obtained by means of these systems approaches 0. In addition, using a computer simulation of the quasi‐stereophonic system of frequency‐division type, psychological tests were conducted. the tests showed that differences in sound image quality were principally due to sound image broadening sensations and distance sensations, and that those characteristics corresponded physically to the absolute value of the correlation coefficient and to the correlation coefficient itself. Further, if the correlation coefficient is zero, the sound image is perceived to be broadened to about the extent of the speaker separation, thus verifying the effectiveness of the new broadening sensation control system.
A derivation of ARMA coefficients using a digital lattice filter
Authors: Suzuki Masakiyo , Suzuki Masatoshi , Miki Nobuhiro , Nagai Nobuo 
Published: July 2007

AbstractA shaping filter for a stationary stochastic process can be viewed as the open‐circuit voltage transfer function of a resistance‐terminated reactance 2‐port. Further, Levinson's theory regarding spectral analysis (AR analysis) based on the autoregression model of a stationary stochastic process is equivalent to Ricca's theorem in network theory. Using these facts, from the digital lattice filter which is developed from the AR analysis, we can determine the impulse response of the inverse of the reflection coefficient at the output of the resistance‐terminated reactance 2‐port corresponding to the stationary stochastic process which is analyzed. In this paper we present a technique in which an AR analysis is performed on an autoregressive, moving average process (ARMA process), the impulse response is approximated by a rational function as described above and, by determining the open‐circuit voltage transfer function, the ARMA coefficients are derived. Also, we present two different regression methods for determining the rational function approximations to the impulse response. In general, there is no guarantee that the rational function approximations determined by these methods will be physically realizable transfer functions, but it has been verified by modeling tests that, for an ARMA process of finite degree, by this technique we can determine ARMA coefficients which are better than those obtained by AR analysis to approximate the power spectrum.
4‐, 5‐, 6‐GHz band offset antenna featuring low sidelobe and high cross polarization discrimination
Authors: Nakajima Nobuo , Shimanuki Yoshitaro , Abe Kohshi , Furuno Takayoshi 
Published: July 2007

AbstractWith increasing congestion of the 4‐, 5‐, and 6‐GHz microwave radio links, an antenna with a good wide angle directivity is desired that can reduce the interference between the links. In the newly developed digital microwave transmission system, discrimination between the orthogonal polarizations used at the same time must be improved especially during fading. Due to the limitation from installation on a tower, small size and light weight are also required in the antenna. to satisfy these requirements, an offset antenna made of three reflectors has been developed. the design objective is to incorporate maximum possible performances within limited dimensional ranges. Since there are many requirements and design parameters, the method of beam mode approximation has been applied so that these parameters and conditions can be evaluated easily. It was found that the causes of degradation of the wide angle directivity are the mirror surface irregularity and the scattering inside the antenna. As a result, the antenna performance has been improved. the antenna made for the test has the same gain as the horn reflector antenna, even though its size and weight are about 3/4 the latter. the sidelobe has also decreased by 5 to 10 dB. Improvement of the cross polarization discrimination has been confirmed experimentally. the present paper describes the design procedure, discussion of the sidelobe reduction, and the experimental results.
Diffraction integral representation of two‐photon‐resonant image up‐converters
Authors: Satoh Kunihiro , Sakuraba Ichiro 
Published: July 2007

AbstractThis paper shows that the Fraunhofer diffraction integral can apply in the analysis of two‐proton‐resonant image up‐converters. Next, the imaging of up‐converters or field distributions of sum frequency light in any observation plane is discussed. This analytical method makes it possible to analyze some systems or effects which can not be treated by geometrical optics, e.g., suitable up‐converters pumped by Gaussian beam, diffractions due to finite apertures, and so on. For an equivalently infinite aperture, the results of geometrical optics must be included in those of the diffraction integral representations. Fourier mode optical systems are also discussed in the same way.
Efficient coding of high‐quality sound by an adaptive prediction scheme
Authors: Hayashi Shinji , Honda Masaaki , Kitawaki Nobuhiko 
Published: July 2007

AbstractA new digital coding system at 64 kb/s, which can transmit wide‐band speech and music signals in digital telephone network, is presented. Adaptive prediction and adaptive bit allocation constitute this system. the input signal is divided into several frequency bands and predictive coding is applied to each band. the dynamic bit allocation, which uses redundancy based on the frequency spectrum concentration, waveform timewise concentration, and periodicity in the case of coding prediction residual signals along with the interchannel power deviation in the case of the stereo signals, is applied and the information compression is achieved. the system parameters of this coding scheme are chosen to maximize the signal to quantization noise ratio. the transmission band was chosen as 8 kHz wide based on subjective tests. the performance of coding schemes is evaluated by the psychological equivalence relation to the log‐companding PCM and by the psychological scale using the category judgment method. As a result, it is clarified that information compression more than twice that of PCM is achieved for the speech and music sound, and the quality close to the original sound can be achieved at 64 kb/s for the monophonic signal and at 128 kb/s for the stereo.
A PCM‐TDMA one dimensional mobile communication system using leaky coaxial cables
Authors: Sakata Shoichiro , Saito Tadao , Inose Hiroshi 
Published: July 2007

AbstractIn TDMA mobile communication systems, synchronization between a base station and mobile stations is a primary problem. This paper proposes a new mobile station synchronization scheme which does not require the propagation delay measurement or very long guard time for a one‐dimensional mobile communication system using leaky coaxial cables (LCX). It shows that a large‐capacity PCM‐TDMA mobile communication system can be realized based on the proposed synchronization scheme, and describes an application method for the train mobile communication system. Mobile station synchronization scheme, signal transmission system, and synchronization scheme between base stations are described. On the estimation of the attainable bit rate from the physical environment of the transmission paths, the required guard time length and the optimum burst length are determined, and the frame structure and the channel control method are described. to demonstrate the feasibility of the system, a signal transmission experiment using an LCX at the estimated maximum bit rate has been carried out and the possibility of high‐speed pulse transmission by means of LCX has been confirmed.
Design considerations in multi‐output DC‐DC converter with magnetic amplifiers
Authors: Koyashiki Tohru , Ogata Tsutomu 
Published: July 2007

AbstractThe multioutput converter has the feature of fewer number of components and high efficiency. to produce more than one highly stabilized output, the corss‐regulation error should be compensated. to compensate the cross‐regulation error in the forward type multioutput converter, this paper proposes a circuit using magnetic amplifier. the circuit analysis is made to give the quantitative expressions for the cross‐regulation error and magnetic characteristics of the saturable reactor. Based on the relation between the dead angle and the temperaturerise of the saturable reactor, the relation between the number of turns and the cross section of the saturable reactor was derived in order to realize a satisfactory constant‐voltage control using magnetic amplifiers. Using the obtained relation, the design as related to the material properties of the saturable reactor and the conversion frequency of the converter is discussed. It is shown quantitatively that the core with a high saturated permeability and low iron‐loss should be used to miniaturize the saturable reactor and the amorphous core will be effective to miniaturize the magnetic amplifier by raising the conversion frequency.
A microwave interferometer system for the displacement measurements of biological subject
Authors: Arai Ikuo , Suzuki Tsutomu 
Published: July 2007

AbstractThe microwave displacement meter based on the principle of phase interferometer has a high sensitivity in detection. However, in the conventional system the measurable displacement width is limited to the order of one half‐wavelength of the microwave, and quantitative information cannot be obtained without calibration. In the system proposed in this paper, a twophase microwave Doppler sensor (10.525 GHz) is used for detecting the reflected signal from the object as a vector, and the displacement is measured directly from the phase. While the high sensitivity of the phase interferometric method is maintained, the measurable width is improved significantly and quantitative measurement is possible. However, in the present method, the offset caused by the existence of unwanted reflectors other than the object can be a problem. Since this is dependent on the measurement environment, the problem is especially severe for biological measurement. In this paper, this offset is calculated by estimation and is shown to be removable. Next, a recurrence formula is derived that is used for calculating the displacement from the phase of the signal vector. the prototype system can measure the displacement width of 36 cm with the resolution of 90 μm. As an example of biological measurement, two‐dimensional body movement measurement in the balancing function test is presented. Finally, the accuracy and resolution of the present method are studied.
A design of high‐Q dielectric resonators for MIC applications
Authors: Imai Nobuaki , Yamamoto Kazuyuki 
Published: July 2007

AbstractA design method of radiation‐suppressed high‐Q dielectric resonators with a metal cap loaded above a dielectric material with high dielectric constant is studied. For exact evaluation of the effect of the radiation‐suppressing metal cap, a semispherical dielectric resonator model with simplified boundary conditon of the metal cap is introduced. As a result, it is found that there exist two modes in this resonator, a dielectric resonator mode and a hollow cavity mode, depending on the size (diameter) of the metal cap, and almost constant resonant frequencies for the change of metal cap size and high unloaded Q factors are obtained in the dielectric resonator mode by selecting the cap size on the optimum range. the validity of the analysis result is confirmed by experiment. Moreover, the resonant frequency and its temperature variation for a cylindrical resonator are studied and it is found that the frequency variation does not depend on the material of the metal cap but greatly depends on the temperature coefficient of the high‐constant dielectric material itself.
A data converter for analog/fuzzy‐logic interface
Authors: Uehara Kiyohiko , Watahiki Takeshi , Miyata Takeo , Taguchi Eiji 
Published: July 2007

AbstractInput signals are often fed as analog quantities into fuzzy logic processing systems. This paper proposes a method for configuring interface necessitated by fuzzy logic systems featuring analog inputs and digital processing. This interface is a data converter which processes input analog voltage signals and outputs digital signals suitable for fuzzy logic processing.The conversion principle is based on the concept of level sets within the fuzzyset theory, i.e., depending on whether a given analog signal belongs to level sets, the signal is quantized and converted to membership grade, simultaneously. Having programmable conversion characteristics, it can realize typical membership functions such as Z‐, ‐, and S‐functions.The operation of the converter, which is configured of counters, a memory, a digital‐to‐analog converter, and a comparator, is verified experimentally as regards a non‐monotonic and asymmetric membership function. the conversion accuracy is then discussed and the causes for error are described.
Two‐dimensional analysis of hot‐electron emission current in MOS FET
Authors: Morimoto Takahashi , Muramoto Susumu 
Published: July 2007

AbstractThere has been growing concern about degradation in MOSFET characteristics due to hot‐electron emission into the gate oxide as device dimensions are scaled down. This paper reports on a two‐dimensional analysis of hot‐electron emission. The emission current is related to the electric field and current distribution in a MOSFET for the purpose of identifying the factors contributing to its increase with device miniaturization. A variety of MOSFET structures, such as conventional, LDD, and double‐diffused MOSFETs are analyzed and compared. The analysis on a conventional MOSFET clarifies that the major factor contributing to the increase in hot‐electron emission in a small‐size MOSFET is the surface electric field intensity near the drain. This implies that the impurity distribution in the diffused drain has a great influence. The numerical analysis shows that the electric field near the drain is decreased in LDD and double‐diffused structures. For a given device size, the impurity density in the lightly doped portion of the drain can be properly chosen to homogenize the drain electric field, resulting in drastic reduction in hot‐electron emission current.
Analysis of soft error in MOS dynamic RAM
Authors: Yoshihara Tsutomu , Takano Satoshi , Taniguchi Makoto , Harada Hiroshi , Nakano Takao 
Published: July 2007

AbstractThe soft error rate of a MOS dynamic RAM is strongly influenced by the energy spectrum of the incident alpha particles, the collecting processes of electric charges generated by them, and the critical charge of the device. When the collected charge distribution is Gaussian, the error rate is well approximated by a complementary error function of the critical charge, which can explain the voltage dependence of the soft error rate; the dispersion of the distribution is also obtained experimentally. The dispersion depends on the thickness of the polyimide film coated on a chip, and the coating improves the error rate by absorbing alpha particles as well as attenuating their energies. The stopping power of the polyimide film is 1.47 × 103times as large as that of air, which is in good agreement with the calculated value.
Piecewise polynomial galerkin approximation to invariant densities of one‐dimensional difference equations
Authors: Kohda Tohru , Murao Kenji 
Published: July 2007

AbstractProposed herein is a piecewise polynomial Galerkin approximation to invariant densities of 1‐dimensional nonlinear difference equations xn+1 = τ(xn) (n = 0,1…), in which map τ is an endmorphism of an interval I. The piecewise polynomial is a linear combination of N × K polynomial bases of degree K‐1; N is the number of partitioned subintervals of I. The approximate solution for K = 1 is shown to be identical to the Ulam‐Li solution. Forthermore, the sufficient condition for the L1 convergence of the approximate solution (K = 2, 3) for large N is given. Numerical experiments demonstrate that the approximate solution for K = 3 produces a significant improvement of the Ulam‐Li solution.
Performance of comb filtering noise reduction method and application to quality improvement in PCM speech
Authors: Nagabuchi Hiromi , Member Regular 
Published: July 2007

AbstractThis paper proposes a method for reducing additive noise from noisy speech signal. The effectiveness of this comb filtering method is demonstrated via experiments. The method is applicable to noise with varying power and non‐flat spectrum. Listening experiments show that the proposed method improves the subjective S/N and the sound articulation of extremely noisy speech. Application of this method for the reduction of quantization noise and noise caused by bit error in PCM speech is investigated. Experimental results indicate that:For error‐free 2‐to‐5 bit PCM the proposed method improves the subjective quality of the speech equivalent to one bit;.For bit error rate ranging from 10−3to 10−1, the proposed method improves the quality of 8‐bit PCM speech equivalent to the reduction of error rate down to about 1/3∼1/5. It is very effective for reducing the quantization noise in 4‐bit PCM speech.The proposed method is particularly useful for improving the sound articulation of extremely noisy speech.
Circuit design of dynamic MOS RAM with consideration of soft error
Authors: Nagayama Yasuji , Kumanoya Masaki , Yamada Michihiro , Yoshihara Tsutomu , Taniguchi Makoto 
Published: July 2007

AbstractDynamic MOS RAMs (MOS (D) RAMs) have been developed according to scaling relationships. But it is necessary to correct the scaling relationships because of soft error. In this paper, a modified scaling law is described based on the assumption that the soft error becomes the governing condition of the scaling law. In addition, a new device structure and circuit configuration are proposed to realize high‐speed, low soft error rate and low power consumption. As a result of applying it to a 5‐V 16‐K MOS (D) RAM, a performance index of 0.6 pJ/bit and soft error rate of 4 × 107device. hours are obtained. The adequacy of the modified scaling law is examined by considering a 12‐V 16‐K MOS (D) RAM with scaling constant k = 1 and a 5‐V 16‐K MOS (D) RAM with k = 2. It is shown that circuit design with consideration of soft error cannot achieve large improvement of the performance index of high‐capacity MOS (D) RAM and that the soft error is an impediment to high‐performance MOS (D) RAM.
The minimum track number of the narrower channel in the signal‐row single‐layer routing
Authors: Manabe Yoshifumi , Hagihara Ken'Ichi , Tokura Nobuki 
Published: July 2007

AbstractSingle‐row single‐layer routing is critically important for the design of printed circuit board or LSI. It is used to obtain realizations for minimal upper and lower channel track numbers U(R) and L(R) out of realizations R that are to make a connective relation without cross connection. Such a relation N̈ (net set) for a set of vertices on a straight line is given, such that (1) U(R) + + L(R), (2) max(U(R), L(R)) or (3) min(U(R), L(R)) can be decreased to a minimum, respectively. Among these tasks, the time complexity of (1) remains unresolved, and (2) has been proven to be NP‐complete. This paper discusses the problem (3), that is, to obtain a realization Rm that makes track number t either for upper or lower channel that has lower number of tracks as a minimum. We will introduce α(N̈), a tangle number of N̈, as a new measure and prove that the measure will be the minimal value of t. Also, we will present an algorithm to obtain α(N̈) and Rm and show that the time required for their computation be linear to the product of numbers of nets and vertices, even in the worst case. This is a fundamental problem that is to be applied to determination of the number of layers needed for a multilayer approach to realize a given net set on the condition that both the upper and lower channel track numbers be limited.
Construction and analysis of a mathematical model in quantum communication processes
Authors: Ohya Masanori , Members Noboru Watanabe, Regular 
Published: July 2007

AbstractThe communication of information by means of laser is an important technique. Therefore, it is necessary to construct a communication theory (quantum information theory) including quantum effects of laser action. Ohya, one of the authors, has studied the quantum communication channel and constructed a compound state for systematic formulation of the mutual information in quantum systems. In this paper, (1) we briefly review the mathematical formulation of quantum communication theory and (2) construct a physical model of the optical fiber communication process in order to examine the qualitative properties of the communication channel.
Group parity check system for important information
Authors: Tanaka Hatsukazu , Momohara Taketoshi , Kaneku Seiko 
Published: July 2007

AbstractCan we prevent human deception or computer crime by cryptography? The main functions of cryptography are “secrecy” and “authentification,” and they are certainly effective for those outside a computer system. However, for the professional insiders who want to attempt deception, no cryptosystem will work well even if the information is protected by advanced cryptography because of the dependence on human conscience. Therefore, based on the concept that only humans can check human deception, we propose a new scheme of data security, the “Group parity check system for important information.” This scheme checks human deception arising in information input by mutual surveillance among people related to the information system. Furthermore, we show how to realize this scheme using the public key cryptosystem, and on a microcomputer. Although this scheme is inefficient because it requires duplex input of information, it will be effective if applied to only important information.
Assessment on characteristics of b‐adjacent error‐correcting code
Authors: Fukunaga Tetsuya , Tazaki Saburo 
Published: July 2007

AbstractAn application of b‐adjacent error‐correcting codes is discussed. The correction of these codes is b‐bits length sub‐block and their word length is b × N (bits) for improving the reliability of the digital video tape recording (VTR) system under the condition that check bits and synchronization bits are within a redundancy of horizontal blanking size. First, analysis is made of word error detection probability when burst errors and random errors are generated independently, and sub‐block error correction probability considering erroneous correction in a compound channel model containing random errors and burst errors. As a result, it is clarified that the generation of erroneous correction can be made extremely small by increasing the sub‐block length, although the sub‐block error‐correction probability increases slightly. Furthermore, the improvement on sub‐block error correction probability by applying the interleaving to sub‐block units is studied and the necessary interleaved length is clarified. Finally, a simple study on the application to digital VTR is made and it is shown that this code is effective as an error‐correcting code for DVTR.