bluuebunny/crossref_metadata_2025 huggingface dataset:
Catalog space allocation at the department level
Authors: Desmet Pierre
Published: July 2007

In this article we describe empirical and normative rules for the space allocation in catalogs and the underlying assumptions regarding the demand function. Usefulness and limitations of the two approaches for measuring demand response functions are studied from an empirical point of view. The empirical space allocation rule, space as a percentage of profit, seems to be a good starting point and can be improved as the initially rather unstable elasticities are better known.
A meta-analysis of effect sizes based on direct marketing campaigns
Authors: Woodside Arch G. , Beretich Thomas M. , Lauricella Marc A.
Published: July 2007

We document the effect sizes (i.e., the strength of a relationship or the magnitude of a difference between variables) of results of direct marketing campaigns that were submitted as entries in the Direct Marketing Association's 1991 Echo Awards Program. A total of 837 Echo Award entries was analyzed. Of these entries, only 211 campaigns were complete to the extent that effect sizes could be estimated. The 211 experimental effects are all defined as response rates (i.e., the percentage of consumers responding for more information from the total number of consumers having been exposed to an advertising campaign). The results indicate that certain direct marketing variables such as the use of color, toll-free phone numbers, response forms, etc., may not in fact have an important influence on response rates. The size of the campaign, however, may influence the response rate, indicating that smaller, more focused, campaigns result in higher response rates.
Opportunities and problems associated with direct marketing
Authors: Morganosky Michelle A.
Published: July 2007

A research void exists in our understanding of how retailers view the opportunities and problems associated with direct marketing in the United States and in an international context. The purpose of this study was to identify and compare opportunities and problems associated with direct marketing in the US and overseas, as reported by US retailers. Opportunities and problems as they relate to technology, government regulation, consumer demand, cultural environment, resource availability, and competition, are analyzed and their implications discussed. Problems associated with government regulation were perceived to be particularly perplexing both in the US and in overseas markets. This would suggest the continuing need for active involvement in the public policy arena by direct marketers.
Frequency of purchase and the prediction of buying behavior in direct mail
Authors: Ganzach Yoav
Published: July 2007

The research investigates the relationship between frequency of purchase through direct mail and the purchase of products offered by mail. Although this relationship proved generally positive, in some instances a negative relationship was found. Two variables are proposed to explain these conflicting results: direct mail preference—the preference of consumers towards buying by mail—and income, which serves as a proxy for the preference of consumers to the particular product. Subsequently, the practice of target selection in the direct mail industry is examined vis-a-vis these two variables.
Direct marketing modeling with CART and CHAID
Authors: Haughton Domlnlque , Oulabi Samer
Published: July 2007

In a recent article in the Journal of Direct Marketing, R. Thrasher gave an introduction to the Classification and Regression Trees (CART) methodology from the point of view of direct marketing. Following up on this work, with the help of a case study, this article investigates further technical aspects of response modeling with CART and Chi-Square Automatic Interaction Detector (CHAID) of practical relevance to direct marketing professionals and researchers and compares the performance of CART and CHAID models built on the same analysis file, finding that the response lifts are very close for both types of models.
The roles of demographics, purchase histories, and shopper decision-making styles in predicting consumer catalog loyalty
Authors: McDonald William J.
Published: July 2007

This article examines the power of demographics, purchase histories, and consumer decision-making styles to predict catalog loyalty behavior. Based on data from two surveys of women's apparel catalog item buyers, the study finds that repeat-prone customers are distinguishable from switchers on several measures. Decision-making style segments exist among regular apparel catalog shoppers that work in combination with demographics and purchase frequencies to predict the probability of loyalty behavior, providing the basis for positioning strategies that appeal to repeat-prone market segments.
The banking industry and the media
Authors: Hoekstra Janny C. , Zwart Peter S.
Published: July 2007

The way decision makers in bank institutions perceive the media that can be used for communicating with their customers cannot be assessed properly if the respondents are not guided by giving them overt criteria for judging the media. When guiding the respondents by giving them such criteria, it appears that three dimensions can be discovered in their perception: effectiveness of the medium, low costs, and image/brand awareness/no irritation. As for the first two dimensions, direct mail shows a second-best score; direct mail scores rather low on the third dimension. Furthermore, there is a cluster of respondents who prefer the media direct mail and telephone. The findings imply that managers lack the knowledge and insight needed for making media decisions. Training in this field is necessary.
Selling by mail in a global market
Authors: Frank Jane
Published: July 2007

Recent technological advances combined with cross-cultural economic interests make probable an explosive increase in transnational direct marketing. Use of credit cards within international networks, international toll-free telephone numbers, and the continued diffusion of life-style trends across cultural boundaries fuel the increase. And, it is widely predicted that the English language will dominate these exchanges. This article analyzes test samples of sales letters to argue that international direct marketers’ efforts currently are marked by cross-cultural differences, and that these are evidenced in certain linguistic, rhetorical, and organizing features that diverge from “prototypical” American direct mail advertising models. The findings suggest that the absence of these features, while reflecting the characteristics of the originating cultures, may pose problems for readers—whether they are native, or nonnative English speakers. In sum, the increasingly powerful role played by transnational advertising compels us to understand better how such communications simultaneously satisfy our need for unification and capitalize on our differences.
Consumer perceptions of mail/phone order shopping media
Authors: Settle Robert B. , Alreck Pamela L. , McCorkle Denny E.
Published: July 2007

A survey of 980 consumers, measured perceptions of five mail/phone order shopping media— magazines, newspapers, television, direct mail, and catalogs, versus retail store shopping—on eight image dimensions: economical, enjoyable, easy, fast, convenient, sensible, practical, and safe. Image profiles differed significantly among media and between them and store shopping, and among demographic categories. Ratings differed significantly by image dimension, which also interacted significantly with media and store shopping. Store shopping images were more favorable than media on all dimensions. Catalog images were distinctly more favorable than those of other media. Mail/phone shopping media were rated least favorably on safety. Nonfinancial risk was suggested as an important impediment to mail/phone order shopping, and selection and choice appeared to distinguish catalogs from other media.
Target output circuits for 4‐GHz band deflection‐modulated EBS amplifiers
Authors: Makishima Hideo , Mitomi Osamu
Published: July 2007

This paper presents the performance, design and fabrication of the target output circuit for a 4‐GHz deflection‐modulated EBS amplifier.

mounted, have beenn obtained. The relationship between the circuit and output performance is analysed; an output circuit for miniaturization and wide ‐ band operation has been designed. A 4 ‐GHz EBS amplifier has been fabricated and its output investigated. Results show that the output circuit for series parallesl type and has wider bandwidth. The 4 ‐GHz EBS amplifier, using microstrip line output and series diode type circuit ,gives a maximum output of 4.7 Wat 4.25 GHZ, a ‐3 dB bandwidth of 300 MHZ and a gain of 16.7 dB ;these experimental values agree well with the analytical results.
Two‐dimensional analysis of monolithic crystal filters using mode‐matching technique
Authors: Sekimoto Hitoshi
Published: July 2007

To perform a two‐dimensional analysis of a monolithic filter (MCF), the distributed parameter analysis based on an approximate two‐dimensional model and the coupled oscillation analysis based on a variational method are used widely. However, the error in the first method is large for a conventional MCF which is designed to prevent nonharmonic higher‐order vibration. This is because approximations are introduced to the displacement distribution. In the second method, the distributed parameter characteristics of an MCF cannot be estimated because it is equivalent to that based on an approximate coupling circuit with lumped elements. This paper introduces a more rigorous distributed parameter method for MCF's based on the mode matching technique. This analysis can also be applied to an MCF with two‐dimensionally placed electrodes. First, the coupling coefficient of a two‐dimensionally placed two‐electrode pair and the filter characteristics of a one‐dimensionally placed three‐electrode pair MCF are analyzed. It is confirmed that the present method evaluates correctly the distributed parameter characteristics of an MCF with a weak energytrapping capability. The conventional methods cannot be applied to this kind of MCF. Next, as an example of MCF's with two‐dimensionally placed electrodes, we treat a four‐electrode pair MCF with an attenuation pole on the high‐frequency side. It is shown that the filter characteristic obtained by the present method can realize the distributed parameter characteristics that cannot be analyzed by the conventional methods. Thus the usefulness of this method for distributed parameter analysis of MCF's with two‐dimensionally placed electrodes is confirmed.
SCF realization based on the simulation of node equations
Authors: Hayahara Etsuro , Asano Yoshikazu
Published: July 2007

This paper presents a synthesis method for LC filters using switched‐capacitor simulations. The relation between the structure of the original LCR circuits and the synchronization of node voltages in an SCF simulating the original circuit is first investigated and a synthesis method is then derived for a low‐pass filter using the results.
Extraordinary traffic handling in the telecommunication network
Authors: Akiyama Minoru , Tanaka Yoshiaki , Yamashita Mikio , Cheong Chong Lit
Published: July 2007

Extraordinary traffic phenomena caused by network failures, disasters and social accidents cause remarkable deterioration of the network throughput and service grade. Algorithms of traffic control, e.g., originating traffic control, code blocking control, alterante route control and time‐out control, have been investigated and some of them have been implemented as countermeasures.

This paper studies analytically the mechanism of congestion and traffic handling behavior of the telecommunication network for focused extraordinary traffic overload in a two‐stage hierarchical network, using an exchange model which has limited call handling capacity. The congestion at every part of the network can be explained by several factors: network configuration; traffic flow pattern of the extraordinary overload; maximum call handling capacity of exchanges; and the number of channels of the links. The increase of repeated calls arising as the result of congestion at exchanges is one of the dominant factors reducing the throughput of the network.
Effects of electron cyclotron resonances in the raman‐type free‐electron laser
Authors: Shiozawa Toshiyuki
Published: July 2007

A Raman‐type free‐electron laser with the pumping source of a transverse periodic magnetic field of right circular polarization is considered theoretically herein. The focus is the effect of a longitudinally applied uniform magnetostatic field on the behavior of the scattered wave. Using both analytical and numerical approaches, special attention is given to the behavior of the scattered wave in the vicinity of electron cyclotron resonances. The major results may be summarized as follows: according to the conditions imposed on the pumping source, the scattered wave becomes either the electromagnetic wave mode or the electron cyclotron wave mode, or it is not excited; further, there appear two kinds of resonance phenomena in the scattering characteristics for the electron cyclotron wave mode. In the vicinity of one of these resonances, the growth rate for the electromagnetic scattered wave is found to take a maximum value, which can be one order of magnitude or more as large as the growth rate for the case without a uniform magnetostatic field.
A geometrical theory of scaling in the sensory system with several inputs and single output
Authors: Takiyama Ryuzo , Member Regular
Published: July 2007

Numerizing and describing various sensations are important in the discussion of human information processings as well as in the construction of an information processing system, simulating human recognition and behavior. This paper considers the psychophysical function when the stimulus is multidimensional and the corresponding sensation is one‐dimensional. We define a state space spun by several physical continua and a psychological continuum, which is regarded as an n‐dimensional Riemannian space. the psychophysical function is defined as a certain geometrical invariant in this space. A metric is introduced into this state space based on the threshold of discrimination, and functions are derived which are permissible in this case as psychophysical functions. As an application of this formulation a problem is considered to establish a correspondence between the luminance and the brightness of the colored light. It is shown that when Weber's law and Ekman's law apply to the threshold of discrimination, Stiles' law and Abney's law can be derived as the permissible psychophysical functions.
A method of statistical design of ARMA group‐delay filters
Authors: Kunimoto Toshifumi , Aoki Yoshinao
Published: July 2007

This paper proposes group‐delay response approximation method based on the ARMA filter, an extension of digital filter approximation by statistical design. Since the denominator and numerator coefficient sequences are in opposite order in recursive group‐delay filters, obtaining either coefficient sequence leads to the other. the approximation described here replaces group‐delay response with the magnitude‐squared response via the complex cepstrum. It is then approximated by an auto‐regressive (AR) filter to obtain the denominator coefficient sequence by linear prediction; reversing this sequence gives the numerator coefficient sequence. A design procedure using the FFT and Levinson‐Durbin algorithm gives a solution much faster than the previous method of solution by means of iterated calculations, in addition to which it is easy to assure that the approximation is stable. A coefficient series allowing realization of a low‐coefficient‐sensitivity recursive structure is directly obtained in the design procedure. Examples of group‐delay equalization and results of radar signal simulation are presented as applications of the approximation method. Finally, some additional problems are considered in connection with the difficulty of obtaining a high‐order approximation with large group‐delay response.
A new frequency synthesizer for coherent communication in frequency hopping spread spectrum multiple access communication systems
Authors: Sugiyama Hisayoshi , Amemiya Yoshifumi
Published: July 2007

Spread spectrum multiple access (SSMA) is a communication system where narrow‐band information spectrum is spread uniformly over communication bandwidth and plural communication parties share the same frequency band at the same time. In frequency hopping SSMA (or FH‐SSMA), PN signals for spectrum spreading of information signal are generated by a frequency synthesizer. Conventional frequency synthesizers cannot generate PN signals which have the same frequency and phase in the corresponding timeslot at the transmitter and receiver sides independently. For this reason, coherent detection is impossible. Although many frequency synthesizers using SAW filter have been proposed for the realization of coherent communication in a frequency hopping system, there are some problems, including errors in synthesized frequency and phase uncontrollability. This paper presents a new frequency synthesizer to realize coherent communication in FH‐SSMA.
New decoding methods of interleaved burst error‐correcting codes
Authors: Nakano Yukio , Kasahara Masao , Namekawa Toshihiko
Published: July 2007

This paper proposes new methods of burst error correction for block interleaved error‐correcting codes. First, a probabilistic method of a single burst error correction, using syndrome correlation of subcodes which constitute the interleaved code, is presented. With this method, the high capability of correcting burst errors potentially owned by the interleaved codes is realized with less decoding delay. Second, by generalizing the above method, a probabilistic method of multiple (m‐fold) burst error correction is presented. With this method, after estimating the burst error positions using syndrome correlation of subcodes which are interleaved m‐fold burst error detecting codes, erasure errors are corrected in each subcode and m‐fold burst errors are corrected successfully. the code constructed by interleaving m‐fold burst error‐detecting codes is shown to be superior to the Reed‐Solomon code for 2‐fold burst error correction with respect to both error correction capability and decoding delay. the performances of these methods (single burst error correction method and multiple burst error correction method) are analyzed by computer simulation and their effectiveness is clarified.
Effects of equalization in graded‐index optical fibers influenced by mode mixing
Authors: Yamamura Tetsuya , Itoh Kiyohiko , Itoh Hiroki
Published: July 2007

This paper describes a theoretical investigation on equalization effects in spliced graded‐index fibers influenced by mode mixing. Mode conversions at splice points calculated by Snell's law and the WKB method are used to derive the baseband response of spliced fibers. First, we discuss bandwidth broadening due to equalization without mode mixing. Then we take into account mode mixing effects. In particular, the effects of index profile (α‐profile) and fiber length on equalization are discussed.
An approach to digital filter equalizing of the multiplier coefficients
Authors: Hirai Hiroshi , Yamane Toshiki , Tsutsumi Kiyoshi , Yuba Yoshiharu
Published: July 2007

The application of digital two‐pair networks in the design of loco‐sensitivity digital filters is considered. Digital twopair networks using parallel connection and certain limited ladder‐type constructions have been proposed. In this paper, digital two‐pair networks using the cascade connection are discussed. In realizing digital two‐pair networks, if the given connection matrix (K‐matrix) is a general rational function matrix it is difficult to reduce the K‐matrix to product form. Therefore, when the K‐matrix is given as a polynomial matrix with determinant 1, the ladder‐type construction is proposed. As an example of the application of the digital two‐pair network, a low‐sensitivity digital filter is considered. A delay‐free loop problem has been noted. In our approach, this problem is solved by including the terminating part of the digital two‐pair network in the K‐matrix. Furthermore, in view of the fact that most multiplier coefficients of the realized lowsensitivity digital filters are almost equal, an approach using digital filter equalizing of the multiplier coefficients is also considered as a digital filter design method.
A practical method of measuring the scattering characteristics of the pyramidal absorber
Authors: Ono Mitsuhiro , Yokoto Takashi , Shibuya Toru
Published: July 2007

Pyramidal absorbers widely used today often exhibit complicated scattering phenomena. From the point of view of measurement equipment and operation, it is not easy to measure these phenomena over wide ranges in frequency and incident angle by the traditional method. In this paper, the direct spatial standing‐wave measurement method for the oblique incident case is studied and extended to the method for measuring the scattering characteristics of the absorber. This method has been used for measurement of the reflection coefficient from an absorber with an oblique incident wave. In the new method, the standing‐wave ratio (or the scattering coefficient) and the scattering angle of the wave with the maximum intensity of all the waves are measured at the front surface of the sample. the measurement error of the standing‐wave ratio around 1.1 (scattering coefficient 0.04762) is less than ±20% in terms of scattering coefficient for the incident angle ranging from 0° to 80°. the error in the scattering angle is less than 6° for the 0° scattered wave and less than ±3° for all other scattering angles. the new method requires only simple equipment and the operation is easy. Therefore, measurement of the scattering characteristics of a pyramidal absorber can be done quickly over wide ranges of frequency and incident angle.
An application of the least square method to optimal control problems
Authors: Suzuki Yoshihiko , Yamauchi Nozomu
Published: July 2007

An approximation method for boundary value problems in optimal control is proposed using the least square method. In this method the least square method is used to solve the Euler equations derived by the well‐known “solution by variation” method so that two‐point boundary conditions are satisfied. In applying the least square method, theorems are proven and this method is shown to satisfy simultaneously the principles of the finite element method and of the formalism of the weighted residual method. Also, the approximation obtained by this method has a characteristic that it is an approximate solution (a polynomial in time t) of the form of a quantitatively analyzable function and it is shown that this characteristic can also be utilized in analyzing errors. Furthermore, when a system in question is of higher order, it is transformed first into a controllable canonical form and then the least square method is applied to avoid a large amount of computation time. Based on that theory a program was written and by solving simple problems, it has been verified that this method is effective in solving the two‐point boundary value problem for ordinary differential equations.
Application of wagner coding method to multi‐DPSK system
Authors: Kobayashi Hideo , Yanagidaira Hidetaka , Shintani Sotokichi , Kawai Kazuo
Published: July 2007

The Wagner coding method utilizing analog information of a received signal in the decoding of single parity check code is known to have a similar ability to that of single error correcting code. Also, it possesses a simple decoding operation. This paper proposes a concrete example of the Wagner coding method applicable to multi‐ DPSK system. Example solutions are shown to the problems such as in the parity check coding scheme which can be used in the DPSK channel, extracting scheme of the channel measurement information in the case of multi‐DPSK system, and the error correcting scheme which can be applied after the differential decoder. Further, the theoretical analyses of BER (Bit Error Rate) performance are made for the case where white Gaussian noise is offered as a signal quality degradation factor and the case where phase jitter is contained in the recovered carrier. Consequently, it is clarified that by simply adding some peripheral circuits to the conventional DPSK modulator/demodulator, the proposed scheme compares favorably with the conventional 4‐DPSK system by 2‐dB improvement in the BER performance against white Gaussian noise and also offers considerable immunity against phase jitter. the equipment is actually fabricated in the case where the proposed method is applied to a 4‐DPSK system and the effectiveness of the proposed method is confirmed through experiments.
Near field distributions around free ends of dielectric waveguide
Authors: Matsumura Kazuhito , Kawamura Hajime
Published: July 2007

The field intensities near the free ends of circular and rectangular waveguides with various end profiles are measured in the microwave frequency range. It is found that there exist characteristic field profiles in front and rear of the free ends depending on the shape, slant angle and normalized frequency. the field is measured by scanning a probe antenna near the free end. the measurement process is semi‐automated with a microcomputer which controls the antenna location and processes measured data. In general, analytical treatment of the discontinuities in a dielectric waveguide is complicated. In this paper, a simplified analysis is introduced for finding approximate values of the field near the free end. From the physical requirement on the field near the free end and the phase distribution on the free end, the electromagnetic field on the free end is assumed. This field distribution is used as a source from which the near field is numerically obtained. the numerical results exhibit characteristics of the measured field except for those near the extremities. the measurement technique and the approximate analysis reported here may be applied to free ends with different shapes.
Recursive ϵ‐nonlinear digital filter
Authors: Arakawa Kaoru , Harashima Hiroshi , Miyakawa Hiroshi
Published: July 2007

A recursive ϵ‐nonlinear filter that removes random noise from signals with sharp discontinuities is proposed. It consists of a linear recursive low‐pass filter with the addition of simple nonlinear fuctions. the proposed filter with a smaller number of taps is as effective as the nonrecursive ϵ‐filter repored previously. Methodologies, realizations, and stability problems of the proposed filter are discussed. It is shown that the filter must be realized in cascade form for stable operation. Realizations of the multistage recursive ϵ‐filter should be used from consideration of stability.
Algorithms for solving systems of nonlinear equations by Kevorkian's decomposition method and their quadratic convergence property
Authors: Yamamura Kiyotaka , Oishi Shin'Ichi , Horiuchi Kazuo
Published: July 2007

Kevorkian's decomposition method is known as one of the methods to decompose a large‐scale system of nonlinear equations into systems of equations with lower dimensions. However, his method suffers from the property that errors are included in the decomposed equations, function values, and the Jacobian matrix. Consequently, it is important to discuss the convergence of the solution algorithm and to improve the convergence speed, taking those errors into account. This paper presents an algorithm for the solution of systems of nonlinear equations using Kevorkian's decomposition method. the convergence property of the proposed method is discussed, indicating that the algorithm gives local quadratic convergence under some suitable conditions. A sufficient condition is given first for the existence and differentiability of the mapping G obtained by decomposition. Then a discussion is made of the errors in the equations and the function values by Kevorkian's method. A solution algorithm is proposed which retains the quadratic convergence under those errors, leading to a theorem for convergence. A numerical example is given, indicating that the quadratic convergence can be realized by the proposed method. A comparison is made with the case without using the proposed method, demonstrating its effectiveness.
An LC simulation active RC low‐pass notch filter by minimum number of capacitors
Authors: Ishibashi Yukio
Published: July 2007

The most important measure in judging the advantages or disadvantages of a synthesis method for an active RC filter is the element sensitivity. One of the powerful methods for minimizing element sensitivity is the well‐known leapfrog‐type synthesis which simulates a doubly terminated LC filter.

In this paper, a method for the synthesis of an LC simulation active RC filter is proposed which can realize a low‐pass notch filter with a minimum number of capacitors. First, how the signs are taken for the node voltages and inductor currents so as to minimize not only the number of capacitors but also the number of operational amplifiers is described; voltage and current relations are derived; and a circuit for realizing these relations and a method for synthesizing an odd‐order filter are shown. Next, the effects of the variation of RC elements and the GB product of the operational amplifiers are described. Finally, a fifthorder low‐pass notch filter is designed and an experiment is carried out. Furthermore, sensitivity calculation is performed using a computer and it is shown that the element sensitivity of this circuit is about 80% that of a circuit realized by conventional leapfrog synthesis.
Analysis of the stability of oscillation modes in parallel‐running oscillators
Authors: Hamaya Susumu
Published: July 2007

There are several oscillation modes in multiple parallel‐running oscillator circuits. to reduce the adjustment of oscillators and coupling circuits, it is important to obtain single‐mode oscillation in the parallel‐running circuits for power combining so that only the desired mode of oscillation is stable and all the remaining modes are unstable. In this paper, all of the oscillation modes existing in a parallel‐running system consisting of several oscillators with identical Rieke diagrams are extracted and their stability is studied. It is shown that single‐mode oscillation can be easily obtained if the operating point of the desired mode is located at a point away from the origin of the Rieke diagram and the operating points of other modes are at the origin. In this case the operating points of different unwanted modes are necessarily found at points away from the origin and these modes may be stable. However, they are not detrimental in the multiple oscillator system. Analysis and experiment are performed for three representative parallel‐ running systems using hybrid elements.
Analysis of optical waveguide junctions by means of an integral equation method
Authors: Nobuyoshi Terumi , Morita Nagayoshi , Kumagai Nobuaki
Published: July 2007

Using a slab waveguide model we analyze the problem of waveguide mode transmission and reflection that occurs at the junctions of dielectric optical waveguide due to lateral offset, angular tilt, and gap between the guides, and deformations of the end faces. the analysis first develops a set of integral equations for the unknown equivalent electric and magnetic surface currents over the end faces. the integral equations are discretized through partitioning of the boundaries of both ends into small elements, and their solutions are expanded in a Neumann series, which makes it possible to obtain the solutions iteratively. Using reciprocity and mode orthogonality properties appropriately, the mode coupling coefficients are obtained. After discussing the relation between partition number of the boundaries and convergence of solutions, and the satisfaction of energy relations, we give numerical examples for the reflection and transmission coefficients of guided modes, the radiation losses and the radiation power patterns, choosing end shapes and their locations as the parameters.
Stacked analog—I2L LSI
Authors: Kaneko Kenji , Okabe Takahiro , Nagata Minoru , Ogura Setsuo , Furihata Makoto , Matsumoto Keizo
Published: July 2007

Recently, with the advance of microfabrication techniques, extremely many circuits are integrated in a silicon chip. As a result, the power density is increased and the processing of this power density becomes a key to realize a VLSI. As a means to resolve this problem, this paper discusses a method for reducing the power consumption in the entire analog‐digital LSI by resuing in the I2L circuit, the current already used in the analog circuit. Several representative analog circuits are studied in this paper and a stacking of the analog circuit and the I2L circuit is investigated. As an example, when an I2L circuit is combined in the constant current souce side of the differential amplifier with the signal gain of 36 dB, the noise leakage from the I2L circuit to the output of the differential amplifier is about ‐14 dB (about 2 mV). This stacked analog ‐I2L is applied to an actual integrated circuit. Without losing the function and characteristics of the original integrated circuit the apparent power consumption of the I2L circcuit is made zero and the power consumption of the entire integrated circuit is reduced from 65 mW to 34 mW, which is about a 50% reduction.
An improved method of estimating electron density profiles in the lower ionosphere with VLF reflection coefficients
Authors: Mambo Masayoshi , Nagano Isamu , Okada Syunji , Fukami Tetsuo
Published: July 2007

Previously, we reported a method (the previous method) for estimating by successive iterations electron density profile in the D layer in which if the absolute phase of the ionospheric reflection coefficient for the VLF wave is known, the perturbation of the reflection coefficient is found to solve the integral equation or the perturbation of the electron density by full‐wave analysis. In the present paper, the previous method has been studied theoretically and the following methods adopted: 1) successive calculation at each frequency; 2) restriction of the computed perturbation of the electron density and the successive extension to the altitude range for the corrected values of the electron density by use of the restricted value; 3) smoothing of the computed density by use of the restricted value; 3) smoothing of the computed results of the electron density; and 4) use of specific initial profile of the electron density. These methods have been applied to the exponential distributions and the measured profiles and simulations have been performed. Improved results over the previous method have been obtained. For instance, the cases that could not have been estimated by the previous method can now be estimated. the estimation range has been increased or the accuracy improved.
Study on contact mechanism and electric resistance characteristics of twisted conductors
Authors: Kuribayashi Masashi , Taguchi Morihiko
Published: July 2007

This paper analyzes the mechanical and electrical characteristics of the hand‐twisted conductor splices in communication cables. the validity of the analysis is verified by experiment. Concerning the mechanical characteristics, it is shown that in the physical contact of the conductors the central axis is twisted with an arbitrary pitch angle on a quasi‐cylinder with the radius equal to that of the conductor. Based on such representation of the contact mechanism, the contact pressure and contact width of the twisted conductors are calculated. Concerning the electrical characteristics, it is assumed that there is a similarity between the current distribution through the twisted conductor contact and the electric lines of force produced by the charge on the surface of contact. Based on such assumption, the constriction resistance of the twisted contact is calculated with consideration of the contact pressure and contact width. Estimation is also made on the growth process of the film resistance and the boundary film thickness due to the chemical substances formed on the conductors in contact. the electrical equivalent circuit for the twisted conductor contact is derived, including the constriction resistance, film resistance and conductor resistance. Using the derived equivalent circuit, an expression is derived for estimation of the contact resistance of the twisted conductors.
Modal expansion theory by almost periodic functions for dielectric gratings
Authors: Yamauchi Norikatsu
Published: July 2007

A new model expansion method is given for analyzing the diffraction of a TE‐polarized plane wave due to a planar dielectric grating in which the dielectric constant varies sinusoidally in the transverse direction. the field components of the incident plane wave and the diffracted wave on the grating surface can be expanded in an infinite series in terms of grating mode functions. Applying the electromagnetic boundary conditions and using the orthogonality of the Mathieu functions representing the grating modes as almost periodic functions, we obtain a system of simultaneous equations which provides the physical meaning of the amplitudes of the reflected and transmitted diffraction waves. Numerical examples are shown for the diffraction efficiency vs. grating thickness and the efficiency vs. incident angle for the grating with the average dielectric constant larger than that of the ambient when the incident angle coincides with the first‐order Bragg diffraction angle as well as when it does not. It was found in each case that a slow undulation occurs due to diffraction in addition to the periodic undulation due to interference from both surfaces of the grating as the grating thickness is changed. It was shown also that anomalous diffractions due to surface wave excitation occur at a specific grating thickness.
Design of two‐dimensional digital filters with complex coefficients
Authors: Baba Yoshiaki , Takahashi Shin‐Ichi , Imamura Kazuo
Published: July 2007

In the field of one‐dimensional signal processing, the concept of analytic signal has been introduced in order to yield a low‐pass expression for band‐pass‐type signals. This analytic signal is obtained by adding the Hilbert transform of the real numbers as the imaginary part to the original signal. One important property of this signal is that its Fourier transform vanishes for negative frequencies, i.e., it “appears only in the positive frequency axis.” This property is applied to the design of one‐dimensional digital filters.

In this paper, a signal processing algorithm using two‐dimensional digital filters with complex coefficients is proposed. This is done by extending the concept of analytic signal to two dimensions; the processing uses the fact that its Fourier Transform “exists only in the right half‐plane of the two‐dimension frequencies plane” or, in the case of quadrantal symmetry, “only in the first quadrant of the two dimension frequencies plane.” Using this algorithm, the degree of freedom for the design of 2D filters is increased and closed design methods for circularly symmetric filters and various new fan filters are possible. Moreover, difficulties of presently known methods such as high‐order requirements and limitations upon the cutoff frequency are greatly relaxed.
Separating capacity of a general two‐layered network of threshold elements
Authors: Takiyama Ryuzo
Published: July 2007

Upper bounds of the number of dichotomies and the capacity of a general two‐layered network of threshold elements are obtained. the network considered is one of the fundamental networks which realize piecewise‐linear machines. In the discussion the equivalent transformation theory from the general two‐layered network to a two‐layered network of committee machine type is positively utilized. As a result, it is shown that an upper bound for the capacity of the general two‐layered network with k threshold elements is equal to 2 (2k‐1 + kn), where n is the number of the dimension of patterns to be classified.
Approximation of two‐dimensional digital filters by separable‐denominator rational function
Authors: Hinamoto Takao , Kukita Hiroshi , Maekawa Sadao
Published: July 2007

An efficient procedure is presented for obtaining a rational function having separable denominator from a given twodimensional (2‐D) impulse response over the first quadrant. First, it is shown that the class of rational functions with separable denominator can be characterized by two 1‐D systems and the given 2‐D impulse response is expressed formally in terms of those of two 1‐D systems. Next, a 1‐D rational approximation is done to each of the impulse responses of two formally 1‐D systems using first‐ and second‐order data from it and the coefficients in the numerator of 2‐D rational function are calculated such that the impulse response of the approximating 2‐D rational function coincides with the given one around the origin. Finally, it is proved that the BIBO stability of the approximating filters is always ensured for given BIBO‐stable 2‐D impulse responses.
Intra‐frame coding equipment using LSI oriented coding algorithm
Authors: Kuroda Hideo , Mukawa Naoki , Okubo Sakae
Published: July 2007

Compact and low‐cost video coding equipment is indispensable for the economical realization of visual communication services such as traffic monitoring entertainment relay, etc. This paper describes an LSI oriented coding algorithm which is effective for the compact and economical realization of intra‐frame coding equipment. First, an intra‐frame combinational difference coding algorithm is proposed. the encoded picture quality obtained using this coding algorithm is sufficient even for complicated scenes of TV signals. the predictive coding circuit LSIs for realizing this coding algorithm are also developed. Moreover, the variablelength word multiplexing circuit is shown to be suitable for LSI, and LSIs for this are also developed. Furthermore, coding equipment using the coding algorithm and the LSIs were developed, and its compactness is confirmed. A coding experiment was performed by using the developed equipment and it is shown that the equipment is capable of transmitting good quality ITV signals at a 32‐Mb/s rate.
Network structure and minimum number of elements in the topological realization of generalized immitance converters
Authors: Matsumoto Tadashi , Hibino Kazuhisa
Published: July 2007

This paper presents a basic discussion for all possible topological minimal realizations of the generalized immittance converter (GIC), which is one of the most important functional two‐ports. In other words, a systematic derivation is presented for the lower bounds for the number of necessary elements in the topological realization of a GIC using nullors and positive resistors, as well as for all of the two‐graphs (voltage and current graphs) for the minimal realization of a GIC from the port characteristics, based on the necessary and sufficient condition for the port‐parameter of an N‐port to be topologically non‐zero. As is anticipated from the general expressions for the port‐parameters, the network structure essentially depends on whether or not the gain of the GIC has unit magnitude. Consequently, the discussion is divided into the cases where the gain of the GIC is of unit magnitude and where it is not. Using the result of this paper, all minimal realizations for GIC, including the newly derived ones, can be derived systematically and easily [4, 9].
Synthesis of wideband switched‐capacitor filter based on approximation theory
Authors: Uno Shintaro , Ikeda Yukio , Takahashi Shin‐Ichi
Published: July 2007

Switched‐capacitor filter (SCF) design methods reported so far fall into one of the following categories: design from the s‐do‐main, in which a filter is synthesized based on a direct approximation to the s‐transfer function; or design from the z‐domain, in which the system is regarded as being discrete and z‐transfer function is used. This paper proposes a new method of SCF synthesis based on an approximate s‐z conversion, starting from a given frequency characteristic. Characteristics of equivalent capacitors and SC integrators are expressed in a variable p(z). The desired characteristic F(s) is then approximated by the least‐square method with a rational function of p, FC(p).

An SCF is constructed from FC(p) using the element substitution method in active FC filter networks. Previously proposed methods of synthesis from the s‐domain based on linear approximation or bilinear transformation result in large substitution errors, especially when relatively low sampling frequency is used. The present method minimizes substitution errors and extends signal bandwidth close to its theoretical limit.
Fluctuation and scattering properties of RF sputtered glass thin film optical waveguides
Authors: Imai Masaaki , Ohtsuka Yoshihiro , Koseki Mamoru
Published: July 2007

The fluctuating scattering properties of a Corning 7059 glass thin‐film waveguide RF‐sputtered on pyrex glass are studied theoretically and experimentally. Light propagating in the thin film waveguide is radiated owing to imperfections of the thin film boundaries and refractive index irregularities in the film. It is thus possible to estimate the imperfection characteristics of the waveguide by comparing the measured scattering pattern with the computed data. An example of the measured results indicates that the correlation lengths of each irregularity are bx/λ ∼ 0.1 and bz/λ ∼ 1.0 and the ratio of the dispersions is G (= Vf/(Vλ)) ∼ 1.0. Here bx and bz are the correlation lengths in the film thickness direction and in the propagation direction, Vf and V are the rms values of the boundary and refractive irregularities, and λ is the wavelength. From these results it is found that both the refractive index irregularity in the thin film and the boundary irregularity contribute to the scattering loss in the glass thin‐film waveguide created by RF sputtering.
An advanced SSBL‐acoustic reference system using a planar hydrophone array
Authors: Igarashi Masao , Nitadori Kazuhiko
Published: July 2007

SSBL (super‐short‐base‐line) is an acoustic reference system in which the angle of incidence (direction cosine) and the slant range of the acoustic wave are estimated to locate the source position. A new SSBL acoustic reference system differing from conventional systems is proposed. The new system uses a planar hydrophone array consisting of many hydrophone elements. When a maximum likelihood estimate is implemented for the direction cosine and slant range measured by a planar hydrophone array, the estimate is given so that the envelope of the spatial‐temporal correlation between the array output and the reference signals is maximized. When the short array condition is satisfied for a planar hydrophone array, this spatial‐temporal correlation is given by the temporal correlation, phase compensation and addition. We obtained the lower bound of the mean‐square error of estimates of the direction cosine and slant range and compared the performance of the system with that of conventional systems. For example, when a square planar array of 4 × 4 = 16 elements is used, system gains of about 16 dB for the direction cosine and 12 dB for the slant range are attainable.
Dynamic MOS RAM by midpoint precharge
Authors: Fujishima Kazuyasu , Shimotori Kazuhiro , Ichiyama Toshio , Mashiko Koh‐Ichiro , Ozaki Hideyuki , Nakano Takao
Published: July 2007

It is shown that a high‐speed, high‐voltage‐level readout is achieved with a dynamic MOS RAM by combining two systems: a precharge system in which the bit line is precharged at VDD/2 and an active store system in which VDD is written into a memory cell while a word line is kept above VDD + VT. It is also shown that the midpoint precharge system is favorable for reducing substrate voltage fluctuations. A 256‐refreshing 64‐kbit RAM was fabricated and the effects of the recharge voltage of the bit line on the refresh characteristic and the effects of precharge voltage fluctuations on the readout voltage were investigated. As a result, the authors obtain a 64‐kbit dynamic MOS RAM with a cell size of 190 μm2, VDD = 5 V, readout voltage of 340 mV for “H” and “L”, VBB fluctuation of 600 mV and access time of 120 ns.