In this paper, millimeter-wave radar cross section (RCS) characteristics for rough surface is investigated by means of an approximation method of the magnetic field integral equation and the feasibility of road condition sensing is discussed. The RCS measurement at 94 GHz is carried out in order to verify the numerical result, thereby the numerical results are in good agreement with the measured RCS. The dependence of RCS on the radar incidence angle and surface roughness is investigated where the cross-polarized RCS characteristic is also considered.

Telecommunication technologies are making relentless progress. In this circumstance, network cost must be evaluated to assess the effectiveness of emerging technologies. To do such an evaluation efficiently, it is necessary to develop a software tool that can calculate the network cost independent of the employed technologies. This paper describes computational techniques used in developing such a software tool. First, the functional requirements are identified to establish a flexible tool that is applicable to a wide range of technologies. One of the required functions is the function that computes the resource amount and the network cost from the given conditions such as traffic demands, a cable duct network, multiplex hierarchy and the specifications of network elements employed. As this computing function, the paper proposes an appropriate path classification scheme that enables us to evaluate the resource amount correctly when a service protection technique is applied to the target network. Namely, the proposed scheme yields evaluations that isolate the primary path route from the backup path route. This isolation is not always provided without classification. In addition, a classification of network elements is also derived for valid estimation of the necessary interface board number, which is a basis of estimating the required network element amount. This classification allows us to identify the exact points of path cross-connection and termination, which affects the number of interface boards. This paper presents the computing procedures that realize path grouping and an estimation of network elements using these classification schemes. Finally, the paper describes a prototype of the tool to confirm the feasibility and effectiveness of the proposed schemes.

To improve the resolution of the color CRTs, we propose a new electrostatic lens system which has two additional electrodes between the focus electrode and the anode electrode. The anode voltage and focus voltage are supplied on these additional electrodes. The numerical simulation shows that the system can reduce the third order aberration coefficients almost up to 31% of the conventional system. And the experiments show that the typical beam spot diameter is improved by nearly 20% of the conventional system.

The coming information society will require images at the high end of the quality range. By using a new method which focuses on the assessment words of the high order sensation, we are investigating the important physical factors for the difficult reproduction of high level, high quality sensation in the electronic capture and display of images. We have found a key assessment word "image depth" that describes appropriately the high order subjective sensation that is indispensable for the display of extra high quality images. Related to the depth of images, we have discovered a new physical factor and the degree of precision required of already known physical factors for the display of extra high quality images. The cross modulation among R, G and B signals is the newly discovered important physical factor affecting the quality of an electronic display. In addition, we have found that very strict control of distortion in the gamma and the step response and the strict suppression of the halation in a CRT display are necessary. We note that aliasing of the displayed images also destroys the sensation of depth. This paper first outlines the overall objective of our work, second considers the important physical factors as important for extra high quality imaging, and then describes the specific effects of cross modulation distortion, gamma, step response, halation and aliasing as they relate to image depth. Finally, the relation of the discussed physical factors with the high order sensation are discussed broadly.

This paper describes subband-crosscorrelation analysis (SBXCOR) using two input channel signals. SBXCOR is an extended signal processing technique of subband-autocorrelation analysis (SBCOR) that extracts periodicities associated with the inverse of center frequencies present in speech signals. In addition, to extract more periodicity information associated with the inverse of center frequencies, the multi-delay weighting (MDW) processing is applied to SBXCOR. In experiments, the noise robustness of SBXCOR is evaluated using a DTW word recognizer under (1) a simulated acoustic condition with white noise and (2) a real acoustic condition in a sound proof room with human speech-like noise. As the results, under the simulated acoustic condition, it is shown that SBXCOR is more robust than the conventional one-channel SBCOR, but less robust than SBCOR extracted from the two-channel-summed signal. Furthermore, by applying MDW processing, the performance of SBXCOR improved about 2% at SNR 0 dB. The resultant performance of SBXCOR with MDW processing was much better than those of smoothed group delay spectrum (SGDS) and mel-filterbank cepstral coefficient (MFCC) below SNR 10 dB. The results under the real acoustic condition were almost the same as the simulated acoustic condition.

Resonant properties of resistively shunted tunnel junctions dominate the high-frequency performance of Josephson array oscillators. To improve the operating frequency, we have developed resistively shunted Nb/AlOx/Nb tunnel junctions with a small parasitic inductance. The inductance was minimized by reducing the inductive length between the tunnel junction and the contact hole to be about 1µm. By fitting the measured I-V characteristics of the shunted tunnel junction to the simulated characteristics, we estimated the inductance to be about 105 fH. The analysis of resonant properties showed that the shunted tunnel junctions with the small parasitic inductance have a high-frequency performance up to the Nb gap frequency. Josephson array oscillators using 11 such junctions were designed and fabricated to operate at 650 GHz and 1 THz. Shapiro steps induced by Josephson oscillation were clearly observed up to 1 THz. By fitting the step heights to the simulated results, we estimated the output power of the Josephson oscillator delivered to the load resistor to be about 10 µW at 625 GHz and 50 nW at 1 THz.

The most basic cross-talk minimization problem is to assign given n intervals to n parallel tracks where the cross-talk is defined between two intervals assigned to the adjacent tracks with the amount linear to parallel running length. This paper solves the problem for the case when any pair of intervals intersects and the objective is to minimize the sum of cross-talks. We begin the discussion with the fact that twice the sum of lengths of n/2 shortest intervals is a lower bound. Then an interval set that attains this lower bound is characterized with a simple assignment algorithm. Some additional considerations provide the minimum cross-talk for the other interval sets. The main procedure is to sort the intervals twice with respect to the length of left and right halves of intervals.

The results of experiments on the effect of the height and diameter of the cup on cup microstrip antennas are presented. The results show that the optimum height of the cup for the narrowest beamwidth and the highest gain is about 1/3 λ, and that the beamwidth decreases and the gain increases as the diameter of the cup increases.

A combined mode-matching and moment method is proposed to calculate the capacitance matrix of wedge-supported cylindrical microstrip lines with an indented ground. Each indent is modeled as a multilayered medium in which the potential distribution is systematically derived by defining reflection matrices. An integral equation is derived in terms of the charge distribution on the strip surfaces. Galerkin's method is then applied to solve the integral equation for the charge distribution. The effects of strip width, strip separation, indent depth, and indent shape are analyzed.

Recent technologies of organic film devices are reviewed. New technologies of fabrication and characterization of organic thin films, electro-mechanical conversion materials, and applications for electrical and optical devices are discussed. In this review paper, especially organic light emitting diodes, tunneling junctions using polyimide Langmuir-Blodgett films, tunneling spectroscopy and high-density recording, plastic actuators using conducting polymers, molecular self-assembly process for fabricating organic thin film devices are reviewed.

In this study the spectral intensities of a breaking arc were measured near the cathode and the anode between separating Pd contacts in a DC 50 V/5 A circuit, and arc temperature and metal-vapor quantity and density were calculated. Results show the radial distribution of temperature in the cross section of an arc column was constant both near the cathode and the anode from the beginning to the extinction of the breaking arc. Near the cathode the arc temperature in the position of the peak value of spectral intensity rose to about 6000 K at the beginning and remained constant, but near the anode it rose to about 6000 K at the beginning and then decreased towards the extinction of the arc. Both near the cathode and the anode metal-vapor quantity and density rose suddenly at the beginning. Afterwards, they fell near the cathode until extinction. But they became constant approaching extinction near the anode. And the metal-vapor quantity was greater and the density higher near the cathode than near the anode.

This paper describes the recently developed 816 delivery and coupling switch (DC-switch) boards for constructing a 320-Gb/s throughput (2. 5 Gb/s 8 multiplexed wavelengths 16 incoming/outgoing link pairs) optical path cross-connect (OPXC) system based on wavelength path (WP) and virtual wavelength path (VWP) schemes. The DC-switch-based OPXC system, compared with conventional space division switch (SD-switch)-based OPXC system architecture, is shown to be superior in terms of; i) high link modularity, ii) upgradability from WP network to VWP network, iii) better transmission characteristics, and iv) lower total switching power consumption. Therefore, the DC-switch-based OPXC system can realize cost-effective optical path networks. The developed DC-switches exploit the silica-based planar lightwave circuit (PLC) technologies, and DC-switch board size is 300330 mm2 (one switch). The worst values of the insertion loss of the board, ON/OFF ratio, and polarization dependent loss are 14. 5 dB, 34 dB and 0. 5 dB, respectively. Moreover, even though switching is realized by thermo-optic effects, the optical output level varies by only 0. 7 dB and 0. 8 dB for ON- and OFF-state signals, respectively, when the environmental temperature is varied from 5 to 65 .

One serious problem affecting the rest and active state images obtained during a functional MRI (fMRI) study is that of involuntary subject movements inside the magnet while the imaging protocol is being carried out. The small signal intensity rise and small activation areas observed in the fMRI results, such as the statistical maps indicating the significance of the observed signal intensity difference between the rest and active states for each pixel, are greatly affected even by head displacements of less than one pixel. Near perfect alignment in the subpixel level of each image with respect to a reference, then, is necessary if the results are to be considered meaningful, specially in a clinical setting. In this paper we report the brain displacements that take place during a fMRI study with an image alignment method based on a refined crosscorrelation function which obtains fast (non-iterative) and precise values for the inplane rotation and X and Y translation correction factors. The performance of the method was tested with phantom experiments and fMRI studies using normal subjects executing a finger-tapping motor task. In all cases, subpixel translations and rotations were detected. The rest and active phases of the time course plots obtained from pixels in the primary motor area were well differentiated after only one pass of the motion correction program, giving enhanced activation zones. Other related areas such as the supplementary motor area became visible only after correction, and the number of pixels showing false activation was reduced.

In this paper, we propose an efficient and powerful crossover operator in the genetic algorithm for solving the traveling salesman problem (TSP). Our proposed crossover is called the complete subtour exchange crossover (CSEX), and inherits as many good subtours as possible because they are worth preserving for descendants. Before generating the descendants, a prerequisite for the CSEX is that it enumerates all common subtours, which consist of the same set in a pair of subtours on the given two tours of n cities. An algorithm to enumerate all common subtours in the CSEX consumes only O(n) time. In a fundamental experiment, we show the experimental number and length of the common subtours for two randomly generated tours with 5 to 500 thousand elements. In addition, we give the practical behavior of the CSEX and compare the CSEX with a hopeful crossover operator using the benchmark instances for the TSP. Moreover, in another experiment of parallel computing, in order to analyze the performance of the CSEX, we compare the CSEX with hopeful crossovers for 25 benchmarks (48 - 2392 city) using a parallel supercomputer, Paragon. From these results, the CSEX shows an extremely bright performance.

We have proposed a non-invasive method for diagnosis of the early stage of atherosclerosis, namely, the detection of small vibrations on the aortic wall near the heart by using ultrasound diagnostic equipment. It is, however, necessary to confirm the effectiveness of such measurement of the pulse wave velocity for quantitative evaluation of the local characteristics of atherosclerosis. It is well known that Young's modulus of a tube wall, estimated from measured pulse wave velocity, depends on inner pressure because of the non-linear relationship between the inner pressure and the change of volume in the tube. The inner pressure, however, changes during the period of one heartbeat. In this experimental study, we found for the first time that Young's modulus of the tube wall, estimated from the measured pulse wave velocity, depends not only on the diastolic pressure but also on the pulse pressure and the pressure gradient of the systolic period.

In a DC 50 V/5 A circuit, the relationship between the number of breaking arcs and the spatial distribution of the spectral intensity of breaking arcs of long duration near the cathode in palladium contact were examined through substitution of the contact surfaces of three different shapes: flat and spherical (1 mm radius and 2 mm radius). Findings show the distribution of spectral intensity in Pd arcs to be influenced remarkably by the shape of contact surface and the number of breaking arcs. However, the temperature of Pd arcs was affected neither by the shape of contact surface nor by the number of breaking arcs. The metal-vapor quantity present differed for flat and spherical surface contacts; however, it was not affected by the radius of the curved contact surfaces or by the number of breaking arcs. Additionally, the longer the duration of the breaking arc, the more metal-vapor was presented in the beginning of the arc. Furthermore, arc tracks on contact surfaces were observed with microscopes, clarifying that the relationship between the area of the clouded white metal on the cathode and the shape of contact surface is the same as the relationship between the existent area of measured spectra and the shape of the contact surface.

Gold on connector contacts is superior in environmental resistance. However, pores existing gold film are source to trigger the corrosion reaction between gold and base metal. For examination of the contacts, it has been popular to apply "Salt Spray Test" and "Sulfur Dioxide Test. " There are some differences of the corrosion products between two tests. Main metal forming the product in Salt Spray is Copper, and main metal in Sulfur Dioxide is Nickel. To investigate the reason, we tried to employ an electro-chemical method. As a result, it was found that there was the difference between the respective galvanic cell combinations generated through pores.

The development of a far-infrared imaging system based on ultrafast THz time-domain spectroscopy has opened a new field of applications of femtosecond technology. We describe the principle of this new imaging technique and report recent progress to augment the possibilities of "T-ray" imaging. These include sub-wavelength-resolution near-field imaging and three-dimensional tomographic reconstruction of a samples refractive index profile.

A 2-GHz monolithic Si-bipolar logarithmic/ limiting amplifier is described. It features a waveform-dependent current phase shifter that compensates for the intrinsic dependence of unit-amplifier phase shifts on input signal amplitudes and layout techniques that minimize crosstalk in Si substrate. The amplifier dissipates 250 mW at a 3-V supply, which is less than 1/4 of that of previously reported ICs. The dynamic range of a received signal strength indicator (RSSI) is 60 dB and the limited-output phase deviation is less than 7 deg. at 2 GHz. Therefore, this amplifier is quite suitable for single-conversion transceivers for broadband wireless access systems.

This paper proposes a high-speed input and output buffering ATM switch, named Tandem-Crosspoint (TDXP) switch. The TDXP switch consists of multiple crossbar switch planes. These switch planes are connected in tandem at every crosspoint. Even if a cell can not be transmitted to an output port on the first plane, it has a chance to be transmitted on the next plane. Cell transmission is executed on each switch plane in a pipeline manner. Therefore, more than one cell can be transmitted to the same output port within one cell time slot, although the internal line speed of each switch is equal to the input /output line speed. The TDXP switch architecture has several advantages in implementation. First, the TDXP switch does not increase the internal line speed in eliminating Head-Of-Line (HOL) blocking. Second, since the TDXP switch employs a simple cell reading algorithm at the input buffer in order to retain the cell sequence, the TDXP switch does not require to rebuild the cell sequences at output buffers using time stamps, as is required by a parallel switch. These merits make implementing the high-speed ATM switch easy. Numerical results show that the TDXP switch can eliminate the HOL blocking effectively and achieve high throughput both for unicasting and multicasting traffic. This switch architecture is expected to enable the development of high-speed ATM switching systems that can realize over 1 Tb/s throughput in a cost-effective way.