bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bifurcations and chaos in sampled‐data systems with nonlinear elements of C1 class
Authors: Ushio Toshimitsu , Hirai Kazumasa 
Published: July 2007

AbstractNonlinear systems contain a phenomenon called bifurcation. In the phenomenon, a small change of the parameter of the system can produce a qualitative change in the system behavior. On the other hand, random behavior in the deterministic system is attracting attention. This behavior is called chaos and is becoming a major problem in engineering. This paper discusses first the bifurcation and chaos in the sampled‐data control system with differentiable nonlinear elements. It is shown theoretically that the fold bifurcation does not occur when the sampling period is changed. Then various kinds of bifurcations are determined analytically for the second‐order system with cubic‐type nonlinear characteristics. It is verified by numerical experiment that the period‐doubling bifurcation can occur. Finally, it is shown that the shape of the strange attractor can change with the sampling period. the result of this study will provide a guide for the determination of the sampling period.
A rerouting scheme for single‐layer printed wiring boards
Authors: Futagami Shin , Shirakawa Isao , Ozaki Hiroshi 
Published: July 2007

AbstractA rerouting scheme is described, which is incorporated into an existing automatic routing system for single‐layer printed wiring boards and hybrid integrated circuits. This scheme is to strip and reroute portions of the current wire patterns so that not only incomplete from‐tos can be interconnected by means of getting rid of blockages, but those conductor paths so far determined which form unnecessarily long detours can be improved. Several implementation results are also shown.
An analysis of error rates for nyquist‐ and partial response‐ baseband‐filtered digital FM with discriminator detection
Authors: Akaiwa Yoshihiko , Okamoto Eiji 
Published: July 2007

AbstractIt has been known that error rates as well as spectrum performances can be improved by adoption of transit‐ and receive‐baseband filters for digital FM/discriminator detection schemes. the present paper studies these modulation/demodulation schemes with baseband filters for Nyquist (NYQ) and class I, II partial‐response (PR) transmission. Error rates are analyzed theoretically with and without consideration of the intersymbol interference due to a bandpass filter. Two methods are obtained: in the former case, a generally applicable calculation method which requires the assumption of a symbol sequence, and in the latter case, a simpler calculation method than that before.The calculated results agreed well with the computer simulated results. In comparison with 2, 4 and 8 level NYQ, 3 and 7 level class I PR and 5 level class II PR, higher performance is given by the method in the order of 7 level class I PR, 8 and 4 level NYQ for narrow band transmission.
Focusing deflection by flexible curved solenoid coil
Authors: Kishi Tohru , Takagi Toshinori 
Published: July 2007

AbstractThe so‐called “drift” of a charged particle annexed to the movement along the magnetic flux lines in a curved coil could be compensated by bending the coil in a letter “S” form (S‐type coil) or by superposing vertically the electrostatic fields to the magnetic fields.For an S‐type coil, when an electron beam accelerated at 2.5 kV was injected into the center of the coil, the focused beam was extracted through the center of the exit plane of the coil. Here, the height of the coil, the horizontal distance between the incident and the exit planes, and the strength of the magnetic fields were 225 mm, 60 mm, and 6.1 × 10−3 T, respectively. In this case, since the exit plane could be moved freely parallel to the incident plane, the focused beam was extracted according to the movement of the exit plane of the coil.Further, when the electric fields produced by a cylindrical static deflector were superimposed vertically to the magnetic fields in the coil with bending angle 90°, a focused beam without any drift was also obtained from the center of the exit plane.Therefore, this focusing deflection system will be available to transport the charged beam or to analyze the energy distribution of charged particles.
Cross‐sectional equivalent circuits and transmission characteristics of multilayered helical lines having magnetic core
Authors: Suzuki Mitsunori , Hosono Toshio 
Published: July 2007

AbstractIt is shown that the transmission characteristics of a cable composed of multilayered media and helical conductors can be solved by network analysis as a radial transmission line problem in cross section. the design method has been simplified for lines such as an H‐line and a multilayer helical line that support surface wave modes. For conventional cable structures the equivalent circuit is given independently for the E‐ and H‐modes if the operating frequency is below the short‐wave range. the circuit elements are then represented as lumped constants appropriate to the medium. the two modes are coupled through the helical conductor, represented by a coupling transformer with a transformation ratio determined by the helical pitch. the equivalent circuit can be simplified by the design condition and as a result the relations between the various cable characteristics and the cable structure and material constants are easily seen, thus easing the problem of cable design. With this method, the transmission characteristics of a two‐layer helical line are calculated and the accuracy is evaluated by comparing the results with those of other methods. It is found that use of a magnetic material in the helix core not only increases the delay effect but also reduces the transmission loss and intensifies the external electromagnetic field.
Design of new structural high breakdown voltage V‐MOSFET—Static shield V‐MOSFET
Authors: Katoh Kuniharu , Shimada Yuuki 
Published: July 2007

AbstractHigh breakdown voltage V‐MOSFETs are difficult to obtain because of electric field crowding at the bottom of the V‐groove. to overcome this problem, a new structure for a V‐MOSFET is proposed. A design method for reverse blocking voltage and a model for on‐resistance are developed.The newly fabricated device has a 1.7 times higher breakdown voltage than conventional V‐MOSFETs and the measured and calculated breakdown voltages of the new device are in good agreement. the formula proposed in this paper predicts a 10% increase in onresistance for the new device over that of conventional V‐MOSFETs.
Complex bases and the complex degree of freedom of LCR networks
Authors: Ozawa Takao 
Published: July 2007

AbstractA complex basis can be defined for a set × of variables such as element currents and voltages (excluding the exciting current and voltage), of a linear lumped‐con‐stant network in the sinusoidal steady state. If a subset Xβ of × is a minimal set that satisfies the condition that any variable in × ‐ Xβ can be expressed as a linear combination of variables in Xβ with constant (not including frequency) coefficients, then Xβ is called a complex basis of X, and the number of variables in, Xβ is called the complex degree of freedom. This paper derives one of the complex bases of the set × of all the element currents and voltages excluding the exciting currents and voltages of the LCR network. Let G be the graph of the network, and consider trees Ti and Tv, together with their cotrees Ki and Kv in G, satisfying the following conditions C1 and C2:

Ti ∩ Kv is a union edge set of current sources and voltage sources;
Under the condition C1, Ti and Tv contain as many capacitors as possible and Ki and Kv contain as many inductors as possible. Let Tsc be a tree of the graph obtained from G by shorting all the edges other than capacitor edges and let K0z be a cotree of the graph obtained by opening all the edges other than inductor edges. Let Ti, Tv ⊇ Tsc and Ki, Kv ⊇ K0z. Then, capacitor voltages of Tv ‐ Tsc, inductor currents of Ki ‐ K0z, capacitor currents of Tv ∩ Ki and inductor voltages and resistor voltages form a complex basis of X.
Generalization of sampling theorem by blurring operation
Authors: Iijima Taizo 
Published: July 2007

AbstractThe sampling theorem established by Someya and Shannon is presntly finding wide applications in various fields. However, it often happens in actual application that the assumption of band‐limitation which is a prerequisite of the theorem is difficult to verify. From such a viewpoint, this paper generalizes the sampling theorem to remedy the problem. the blurring operation originally has the function of positively suppressing the higher‐order harmonic components. It is a regular linear operation for which the inverse operation exists. Utilizing this property and combining the operation with the traditional sampling theorem, a new sampling theorem is derived, by which only those components of the object function in the limited band can be extracted. the generalized sampling function derived first in this paper is a natural extension of the traditional sampling function. With its analytical structure as well as the clearly stated method of computation, the generalized sampling theorem derived in this paper is applicable widely to actual problems.
Topological condition for the nonlinear resistive networks to have a unique solution
Authors: Nishi Tetsuo 
Published: July 2007

AbstractIn a nonlinear resistive network composed of nonlinear resistors, of which the v‐i characteristics can be represented by a strictly monotone increasing function, linear resistors, dc sources and dependent sources, the number of solutions for the network equation depends generally on the network parameters including nonlinear characteristics, resistances, source values, and transmittances of dependent sources. For a certain class of networks, however, the solution is unique for all network parameters. For example, Nielsen and Willson gave the topological necessary and sufficient condition for the network consisting of transistors represented by the Ebers‐Moll model, the nonlinear resistors mentioned above and dc sources to have a unique solution. It is important from a theoretical viewpoint to examine the condition for the uniqueness of the solution for more general types of networks. This paper gives the topological necessary and sufficient condition for the network consisting of nonlinear resistors, linear resistors, dc sources and current‐controlled current sources with transmittance α in the range 0 < α < to have a unique solution for all network parameters.
Pattern synthesis for waveguide slotted array antenna by linear programming
Authors: Hara Yasuhiko , Goto Naohisa 
Published: July 2007

AbstractThis paper discusses pattern synthesis to obtain a fan beam with slot array antennas created on the narrow wall of a waveguide. Traditional pattern synthesis methods of this kind of antenna include the sampling technique of a continuous source distribution over the antenna aperture and the approach in which each slot is treated as a discrete source. In this paper, the locations of slots derived by the sampling method are used as the initial values. the current amplitude and the location of each slot are corrected by linear programming so that the antenna efficiency is improved.Although the problem of finding the correct amplitude in each slot is a linear problem, that of correcting the slot location is nonlinear. Hence, linear programming is applied to the latter by linear approximation. A successive method is studied in which the amplitude and location of the slot are alternately and repeatedly modified. the antenna efficiency of ‐3 dB has been improved to ‐1 dB. the effect of fabrication inaccuracy on the optimally designed antenna is compared to that based on the traditional design.
Calculation of the allan variances for the rain‐attenuated millimeter wave beacon from a geostationary satellite, and their application to the site‐diversity switching
Authors: Yoshimura Kazuyuki , Shinozuka Takashi , Suzuki Yoshiaki , Mineno Hitoshi , Shimada Masaaki , Kuroiwa Hiroshi 
Published: July 2007

AbstractWe calculated the Allan variance (the frequency stability measure in the time domain) of a rain‐attenuated 34.5 GHz beacon signal transmitted from a geostationary satellite. the obtained results showed that the rain‐attenuated signals basically had random‐process characteristics with fα (α < 0) types of power spectral densities‐typically with α = ‐2, i.e., a random walk process. Also calculated were the Allan variances of bit error rates (BER's) of time division multiple access (TDMA) signals which were attenuated by rain. Occasionally, the measurements showed that the variances were reduced to only a few seconds. We applied these results to sitediversity switching experiments and tried to determine optimum times to measure and compare the BER's of the TDMA signals to be switched (they came from both routes of the main and substations). Simulation experiment results showed that the measuring times to minimize the variances coincided almost with those to minimize switching errors. This was also proved by theoretical analysis.
Dielectric properties and auger electron spectroscopy on anodized thin‐film capacitors of Ta‐AI‐N
Authors: Sasaki Katsutaka , Umezawa Toshiji 
Published: July 2007

AbstractThin‐film capacitors have been fabricated by anodization of Ta‐AI film in an atmosphere which includes O to 5% nitrogen without degradation of quality at 300°C. This type of Ta‐AI capacitor has tan δ and temperature coefficient of capacitance (TCC) which are smaller than those of Ta‐AI film without nitrogen even before heat treatment. These values are further decreased after heat treatment in air. to clarify this effect, Auger electron spectroscopy is conducted to find the depth profiles of the elements. It is found that a nonstoichiometric oxygen diffusion layer between the base metal and an anodized layer is reduced by heat treatment.
Extended‐BCH codes using fourier transform over a finite field
Authors: Miyabe Yoshiyuki , Tokiwa Kinichiroh , Kasahara Masao , Namekawa Toshihiko 
Published: July 2007

AbstractThis paper proposes a new construction method of extended codes based on BCH code using a Fourier transform over a finite field. This method applies encoding to a so‐called “tail” which is added for extension and, furthermore, repeats similar encoding to the encoded tail. the constructed codes based on primitive BCH codes generally are excellent in the point of code rate (= number of information symbols/code length) and it is clarified through examples that some of them improve the lower bounds of the maximum code rate. Since the extended codes constructed by this method can generally be considered over an extended field of one degree lower order compared with the shortened codes with the same code length, the number of multiplications needed for syndrome‐calculation in decoding can be reduced to about a fourth. Moreover, it is shown that when the code is constructed by this method, the fast Fourier transform algorithm can be applied to a wider range of code lengths than before in syndrome‐calculation.
Diffraction of an electromagnetic plane wave by a slit in a lossy dielectric slab
Authors: Yoshidomi Kuniaki , Aoki Kazuo , Uchida Kazunori 
Published: July 2007

AbstractDiffraction problem of an E‐polarized plane wave by a thick slit in a lossy dielectric slab is analyzed. the Fourier transform technique is used to formulate the problem and the Wiener‐Hopf method is utilized to solve it. Our numerical results revealed the following:

maximum values of diffracted fields are not located in the incident direction or in the direction of coherent reflection;
amplitudes of total electric fields behind the slab are not necessarily maximum in the incident direction;
in the case of a thin slab the maximum amplitudes of diffracted fields are proportional to |1 ‐ T| at the back of the slab and to |R| in front, where T is the transmission coefficient and R is the reflection coefficient for an infinitely long slab;
when a slab becomes more lossy, diffracted fields converge asymptotically to some constant values.
Theory of interpolation by M‐times continuously differentiable piecewise‐connected polynomials
Authors: Iijima Taizo 
Published: July 2007

AbstractImportant in practice is the problem of interpolation of a set of sampled values of a continuous function given at equally spaced points. A number of studies is performed. Although the spline function has been talked about recently for an interpolation method by piecewise polynomials, it has a deficiency of unnatural irregularities when applied to video displays. This paper derives theoretically an actual form of piecewise‐interpolation polynomials continuously differentiable M times in the entire range. As the condition for the interpolation functions to maintain natural features, we require: (1) that the effect of the interpolation to each sampled value remains in the finite range; and (2) that the perfect interpolation is accomplished if the shape of the original function is a polynomial of order less than M + 1. the lowest‐order interpolation polynomial satisfying these requirements is found. the interpolation functions found here are in the form of weighted average by way of an individual piecewise‐interpolation polynomial system. This is because such a form is considered convenient for application to theoretical analysis in the picture processing.
Multivariable adaptive iir filtering
Authors: Kikuchi Akira , Omatu Sigeru , Morisue Toshiya , Arimoto Suguru 
Published: July 2007

AbstractThe necessity for adaptive signal processing is recognized widely in applications to communication and control fields. Also, adaptive signal processing for a multivariable system is an important problem. This paper proposes techniques based on gradient consideration for multivariable adaptive IIR filtering, which is constructed from IIR structure having infinite impulse response. the treatment of the gradient shapes the form of the algorithm for adaptive IIR filtering, since the output of the IIR filter is a nonlinear function of the parameter estimates. Thus we consider first a basic algorithm and then construct four adaptive algorithms for multivariable adaptive IIR filtering. to develop a theoretical consideration, we analyze the convergence behaviors of the four proposed algorithms in 1.i.m. sense after proposing new equalities about Kronecker's product. Furthermore, we consider applications of multivariable adaptive IIR filtering to several data processing fields.
Bandwidth design and operating condition adjustment of high‐speed digital optical repeaters
Authors: Hakamada Yoshiro , Suto Koh‐Ichi , Tsuyuki Shigeru 
Published: July 2007

AbstractBandwidth design is described for the amplifier and reshaping circuit that determine the receiving sensitivity of a digital optical repeater. Also described is the optimum adjustment of the operating conditions as determined by the combination of the amplification factor of an APD and the discrimination level. For the former, the required conditions are clarified for the clamp circuit as a low‐cut circuit. the relations are obtained between the peak value variation of the output voltage of the clamp circuit and the bandwidth of the reshaping circuit. For operating condition adjustment the repeater operation is formulated under various degradations and the relation between the causes of degradation and the SNR is analyzed. Based on these findings, various adjustment procedures are compared. It is shown that the system has sufficient tolerance to these degradations if adjustment is made for intersymbol interference.The present study provides a basis for choosing the conditions for the clamp circuit as a low‐cut circuit and the bandwidth for the reshaping circuit. A method of adjusting the operating condition is found that provides sufficient tolerance to degradation of an optical repeater.
Interactive decisionmaking: For multiobjective convex programming problems
Authors: Sakawa Masatoshi 
Published: July 2007

AbstractThis paper presents a new interactive multiobjective decisionmaking technique for multiobjective convex programming problems based on the weighting method. In our interactive scheme, after generating a Pareto optimal solution by the weighting method, the values of the marginal rates of substitution (MRS) assessed by the decision maker (DM) are used to update the weighting vector. As a result, the increased value of the DM's unknown utility function is sought and the local proxy preference function is updated to determine the optimal parameter value involved in the weight updating formula. In this way, the preferred solution of the DM is derived efficiently from among a Pareto optimal solution set by assessing his MRS. Furthermore, considering the imprecise nature of DM's judgments, the MRS of the DM presented in a fuzzy form are interpreted as L‐R fuzzy numbers, and the fuzzy version of the algorithm is also presented. Based on the proposed algorithm, a time‐sharing computer program is written and the interaction processes to solve a numerical example under the hypothetical DM are demonstrated together with the computer outputs.
Analytical method of spiral line
Authors: Nakamura Takashi , Sekine Toshikazu , Yokokawa Senji 
Published: July 2007

AbstractThe spiral line shows promise for miniaturization of circuits because it has the characteristics of a strip line and has a nonlinear structure. However, analysis of this line is difficult because of nonperiodic coupling between the conductors. This paper proposes a theoretical analysis to determine the distributed parameters for a traveling‐wave mode along the line. Theoretical analysis and experimental investigation are performed for the propagation characteristics of the spiral line. the innovative feature of this method is that the series impedance and the parallel admittance due to the primary constants of the line are expressed as integrals of the current distributions. From these expressions the distributed parameters for the forward wave and the backward wave are given in a series form containing complete elliptic integrals. These distributed parameters comprise the relations between the line structure and the frequency and represent the nonperiodic coupling between conductors. Using this method, we obtain the input admittance of the spiral line with its end open or shorted. Since the results agree well with measured data, validity of the method is confirmed. It is also shown that the frequency characteristic of the distributed parameters express that of the input admittance.
A theory of digital picture restoration by using the generalized laplacian—successive elimination method
Authors: Matsuo Moriyuki , Kondo Shozo 
Published: July 2007

AbstractA digital image is represented by elements of a vector space whose dimensionality equals the number of pixels and linear spatial degradation of a picture is regarded as a linear operator on the vector space. In existing picture restoration theories, especially the theory using a numerical analysis method, this operator is represented by a matrix and the restoration problem is treated as that of obtaining the generalized inverse. In this restoration theory, as the number of pixels increases, the dimensionality of the matrix becomes so large that it becomes very difficult to compute the inverse matrix. In this paper, the generalized Laplacian which is constructed from the linear operator representing degradation is introduced and, by using this operator, the original picture can be restored with high accuracy, simple operations and short computation time. This theory is very effective if the degradation operation is shift‐invariant.