A folded short in parallel-plate waveguide is investigated using the Fourier transform and the mode-matching. A fast-converging series solution for scattering from the folded short is obtained and its characteristics are presented. Our solution for the E-plane short agrees well with measurements and is numerically more efficient than the existing moment-method solution. The presented scattering characteristics are useful for the design of the E- and H -plane shorts in rectangular waveguide.

With a view to applying to the active matrix displays, micromechanical electrostatic switches having Si-N both-ends-fixed beam of size 1.4 µm by 23 µm grown with LP-CVD on Si wafer were studied about its kinetic switching characteristics, especially its switching speed and hysteresis behavior. Electrostatic beam sticking problems were improved with the additional inverse polarity and short duration pulse following on the turn-on signal. The switching beam deflection of 0.16 µm with the switching time of less than 100 nsec. was measured by tightly focused laser interferometric method. Observed turn-on threshold voltages were more than 30 V, and the on/off hysteresis widths were from one third to two thirds of its threshold voltage. The memory function was experimented for the 2 msec. long holding period with the hold voltage of 25 V following on the writing pulse with the duration of 2 µsec. and the amplitude of 32 V. Now, planarization process has been considered to imtroduce the contact electrodes that were not built-in for these experiments. Although conductive actual switches were not tested, with the obtained results, it seems that the micromechanical electrostatic switch has the large potentials as an active matrix element in display panel especially in electro-luminescent devices or field-emission devices.

Standard Site Method (SSM) is theoretically analyzed using matrix representations to examine its validity and develop an improved method. The analysis reveals that the SSM yields an antenna factor specifically related to the effective load impedance presented by the cable and associated devices which are disconnected from the antenna during the SSM site attenuation measurements. Therefore, an additional conversion is required to determine the desired antenna factor under actual load conditions. It is also concluded that the SSM is not applicable to antennas having height-dependent antenna factors. In addition, the SSM correction factors are found to be theoretically inappropriate. Uncertainty of the antenna factor obtained using the SSM is discussed and the required antenna separation distance is investigated. To improve the existing SSM, it is proposed that both transmitting and receiving antennas are placed at the same height during the site attenuation measurements. Experiments exhibit the superiority of the improved method.

We developed an on-chip memory tester macro using a microprogram ROM BIST circuit. Only slight modification of address buffers, data bus I/O circuits and control clock generators of the memory core circuits was required to implement this BIST macro. We fabricated a 1 Mb DRAM with the BIST, and experimental results showed that the measured shmoo plot of VCC versus the cycle time by the BIST closely agreed with that of a memory tester. Disagreement was caused by test address signal set-up time delay and VOH/VOL differences in both test conditions. The BIST macro will be especially useful for design-for-testability of embedded memories.

The previous literature on consecutive k-out-of-r-from-n: F systems give recursive equations for the system reliability only for the special case when all component probabilities are equal. This paper deals with the problem of calculating the reliability for a (linear or circular) consecutive 2-out-of-r-from-n: F system with unequal component probabilities. We provide two new algorithms for the linear and circular systems which have time complexity of O(n) and O(nr), respectively. The results of some computational experiments are also described.

In the early stage of hyperthermia, a large number of engineering efforts have been done in the development or the improvement of the heating and temperature measuring techniques. However, they were not always satisfactory clinically. Thus, even in this moment, various engineering researches as well as the electromagnetic techniques for hyperthermia should be build up rapidly. This paper describes some of the highlights of developed or ongoing electromagnetic heating techniques in hyperthermia and identities a trend of emerging electromagnetic heating. Furthermore, the author emphasizes that few medical engineering efforts have been done in the boundary field between pure physics and clinics, and the proper way to develop the hyperthermia equipment is the best use of successes in the three essential regions: Physics, Biology and Clinics.

A method for painting a sequence of monochromatic images is proposed. In this method, a color model, whose base components are hue, saturation and intensity, is used to keep the lightness of images unchanged before and after painting. Two successive frames in the monochromatic image sequence and a colored image of the first frame which is interactively painted, are analyzed in order to paint the next monochromatic frame. The painting process is composed of two phases, that is, an automatic coloring phase and an interactive retouching phase. In the automatic coloring phase, hierarchical image segmentation and region matching procedures are performed, and the two attributes of hue and saturation are mapped from the painted image of the first frame to the next image. In the retouching phase, using an interactive paint system based on the color model, users can modify the chromatic components of pixels whose colors were not mapped correctly. Several experiments show that our method is very effective in reducing tedious painting.

This paper describes, based on generation mechanism of conductive noise, that the real conductive noise on AC-mains can't be measured by LISN and 50 Ω-input impedance instrument specified by regulations such as CISPR. Second, it is pointed out that one of the causes of poor reproducibility in radiated emission measurement is the difference among line impedances of AC-mains. Finally, it is insisted that the apparatus such as LISN is necessary for stable measurement of radiated emission, and what improvement on LISN characteristics for higher frequency range should be done is introduced.

For estimating the radiated emission from a metallic enclosure, the authors have developed a numerical computational method which applied inverse analysis. A metallic enclosure containing a loop antenna was set up to be a model source for the numerical analysis. Magnetic fields around the enclosure were measured by measurement systems fabricated in the authors' laboratory. Using the measured magnetic fields, current distributions on the enclosure surface were determined by means of an inverse analysis utilizing the least squares method. From this surface current distribution, the electromagnetic field distributions were estimated by forward analysis on a cylindrical surface 3.0m in radius. The amount of the error in the estimated fields distribution was also discussed.

Concerned is a spectral profile of electromagnetic (EM) emission from a signal line on a high-speed digital circuit. The authors have proposed and examined an a priori method to predict the peak frequencies on spectral profile of EM emission from printed circuit boards (PCBs). Profile of an EM spectrum is determined by the resonance of digital circuits. It is the purpose of this paper to investigate the parameters that determine the spectral profile of EM emission from a signal line on a PCS. In this paper, measurements and calculations of EM spectra were carried out for different load capacitances. EM emissions were measured with a small loop antenna at a 50mm from the surface of the PCB. Measured EM spectra had two peaks. Calculated EM spectra, which was based on transient current given by the analog simulator SPICE, had two peaks too. Results of calculations of EM spectra for different internal capacitances of an IC tell that lower peak frequency is determined by the resonance frequency of the resonant loop which is composed of an IC package and a decoupling capacitor. Comparison with measured EM spectra and calculated EM spectra for different load resistances tell that sharpness of the other peak depends on Q factor of a resonant loop which includes a signal line. Therefore the peak frequencies of EM emission spectrum can be predicted as two resonance frequencies of two resonant circuits.

A system for measuring the low frequency amplitude and phase noises was set-up, with employing a phase sensitive detector and phase-shifter. It is noted that both noises were partly correlated. The phase noise was explained by the transit time fluctuation due to the fluctuating diffusion coefficient. The amplitude noise reduction was demonstrated by applying the inverted output of the phase noise to the amplitude noise.

The effects of Gaussian electromagnetic noise and non-Gaussian one on TV picture degradation are studied by using a composite noise generator which can control noise parameters. Three kinds of still pictures and four kinds of motion pictures are tested, and the picture degradation is subjectively evaluated with five-grade impairment scale. The tendency of the picture degradation against the every picture is almost the same. But MOS (Mean Opinion Score) between still picture and motion picture degradation is different in some measure when the power of burst noise is small.

A new electrostatic wobble motor design and fabrication method were proposed, and micromotors were successfully fabricated and operated. The advantages are (1) thicker structural size, resulting in larger torque, (2) simple and safe fabrication process and (3) needle-shaped bearing to support the rotor. Needle-shaped bearing used here is expected to have lower friction comparing with the existing motor, since the load is smaller for this kind of bearing structure. Two major sources of the load, electrostatic force and capillary force, were considered to prove this tendency. Diamond-like Carbon (DLC) film was employed as a solid lubricant for its bearing. The friction of DLC and that of ilicon-dioxide were compared by experiment.

GaAs-based micromachining is a very attractive technique for integrating mechanical structures and active optical devices, such as laser diodes and photodiodes. For monolithically integrating mechanical parts onto laser diode wafers, the micromachining technique must be compatible with the laser diode fabrication process. Our micromachining technique features three major processes: epitaxitial growth (MOVPE) for both the structural and sacrificial layers, reactive dry-etching by chlorine for high-aspect, three-dimensional structures, and selective wet-etching by peroxide/ammonium hydroxide solution to release the moving parts. These processes are compatible with laser fabrication, so a cantilever beam structure can be fabricated at the same time as a laser diode structure. Furthermore, a single-crystal epitaxial layer has little residual stress, so precise microstructures can be obtained without significant deformation. We fabricated a microbeam resonator sensor composed of two laser diodes, a photodiode, and a micro-cantilever beam with an area of 400700 µm. The cantilever beam is 3 µm wide, 5 µm high, and either 110µm long for a 200-kHz resonant frequency or 50 µm long for a 1-MHz resonant frequency. The cantilever beam is excited by an intensity-modulated laser beam from an integrated excitation laser diode; the vibration signal is detected by a coupled cavity laser diode and a photodiode.

Effects of various joint configurations and gap sizes on the electromagnetic shielding effectiveness (SE) are evaluated to provide guidelines for best design of joints in order to increase the value of SE. Four different joint geometries are presented. A sharp decrease on SE with larger gap size for simple joints is observed. Addition of bends in the joint geometry has strong positive effect on the value of the SE. Increasing the angle of cut, which increases the effective length of the joint were also demonstrated to have increasing effect on the shielding performance.

Broadband antennas such as biconical antennas and log-periodic dipole antennas are generally used in automatic EMC measurements. However, these broadband antennas have not been used for accurate measurement because accurate specifications for them are lacking. Therefore, more accurate analysis is urgently required by the CISPR (International Special Committee on Radio Interference), to establish the specifications for broadband antennas for EMC measurements. In this paper, the AF of biconical antennas is calculated by using Moment Methods. The frequency characteristics and antenna height dependency of AF are presented. AF is also measured and compared to the data obtained by the calculations. Good agreement between the calculations and measurements is achieved, indicating the usefulness of our computation method. In addition, the effect of antenna separation distance and transmitting antenna height on AF is investigated. The calculated AF deviation from the reference value is nearly 0dB except for certain antenna arrangements. In these antenna arrangements, the field becomes null at the receiving antenna and widely varies in magnitude and phase around the null points. Therefore, the antenna is immersed in a non-uniform field, while the AF is defined on the assumption of a uniform field. Consequently, the erroneous AF will be derived from measurements around these null points and it will be greatly different from that obtained at other antenna heights. Thus, it is better to avoid these conditions during actual measurements. The effect of the ground plane on AF is also evaluated. AF is shown to be seriously affected by the ground plane especially at frequencies around 90MHz. It should be noted that AF deviation has crests corresponding to the null field at 300MHz. The obtained data will be useful in establishing specifications of biconical antennas for EMC measurements.

In this paper, we consider ZKIPs for promise problems. A promise problem is a pair of predicates (Q,R). A Turning machine T solves the promise problem (Q,R) if, for every x satisfying Q(x), machine T halts and it answers "yes" iff R(x). When ¬Q (x), we do not care what T does. First, we define "promised BPP" which is a promise problem version of BPP. Then, we prove that a promise problem (Q,R) has a 3-move interactive proof system which is black-box simulation zero knowledge if and only if (Q,R) ∈ promised BPP. Next, we show a "4-move" perfect ZKIPs (black-box simulation) for a promise problem of Quadratic Residuosity and that of Blum Numbers under no cryptographic assumption.

A simple solution for the right-angle H-plane waveguide double bend is obtained in analytic series form. The simultaneous equations are solved to obtain the transmission and reflection coefficients in fast convergent series forms. The numerical computations are performed to show the behaviors of the transmission coefficient versus frequency.

The validity of numerical design scheme of CP-PASS (Circularly Polarized Printed Array antenna composed of Strips and Slots) is considered. The strip element of CP-PASS is composed of a strip dipole and a window which increases the frequency bandwidth of the strip element. With the window, however, analysis of the antenna becomes difficult if a simple analytical model is used. The previous design procedure requierd an experimental procedure. By using modern computers, the FDTD (finite-difference time-domain) method becomes powerful tool for the analysis of 3D-structured antennas. In this paper, numerical results of the FDTD analysis for CP-PASS is compared with results from experiments. The characteristics of the unit-radiator of CP-PASS are demonstrated numerically. This paper shows that CP-PASS can be designed numerically and a new path has opened in the study of CP-PASS.

In this paper, the influences of the cross-sectional deformation on the coplanar waveguide (CPW) characteristics for the use of Ti: LiNbO3optical modulator are presented based on quasi-static analysis. In particular, the influences of the changes in the thickness of Ti: LiNbO3 substrate and the cross-sectional shape of electrodes are studied in detail by using the finite element method proposed previously. As a result, it is found that the propagation characteristics of the dominant mode change significantly with the thickness of LiNbO3 substrate when it is less than 100 µm. It is also shown that an inverted trapezoidal deformation of the electrode cross section is promising because a wider electrode gap and thinner electrodes are available in the design of optical modulators.