A new method for discrimination of ground faults causes in distribution lines

Since most problems in distribution lines are ground faults, the technology to distinguish the causes in the distribution lines will be very useful in preventing faults beforehand or, at least finding any problems at an early stage. The waveforms of ground faults which were collected from data concerning problems in the distribution lines and ground fault experiment are analyzed. The technology which could predict classified groups drawn from the scale of I₀ (the waveform of ground fault current) and V₀ (the waveform of ground fault voltage), and both of them in the ground faults is studied. The results demonstrated that I₀ could be classified into three groups, that is, leaking ground faults are sine curve shaped, gap discharge ground faults are triangular, and intermittent discharge ground faults are needle shaped. Also, simulated equivalent impedance of the causes of ground faults by EMTP is calculated. Furthermore, the influence caused by the condition of the distribution lines is investigated. With these results, a technique is proposed which could predict the cause of problems in ground faults.     

An Integrated Sideband-Separating SIS Mixer Based on Waveguide Split Block for 100 GHz Band with 4.0–8.0 GHz IF

We have developed an integrated sideband-separating SIS mixer for the 100 GHz band based on the waveguide split block. The measured receiver noise temperatures with 4.0–8.0 GHz IF are less than 60 K in the LO frequency range of 90–110 GHz, and a minimum value of around 45 K is achieved at 100 GHz. The image rejection ratios are more than 10 dB in the frequency range of 90–110 GHz. We have installed the sideband-separating SIS mixer into an atmospheric ozone-measuring system at Osaka Prefecture University and successfully observed an ozone spectrum at 110 GHz in SSB mode. This experimental result indicates that the sideband-separating SIS mixer is very useful for astronomical observation as well as atmospheric observation.     

Effect of Embraced Lipid on the Gelatinization of Rice Starch

Quantitative evalution of starch-lipid interaction was attempted by means of amylography, the degree of gelatinization, iodine affinity, iodine color intensity, solubility and swelling power using isolated non-defatted, defatted, and re-embraced or impregnated starch with fatty acids, whose starch was isolated from non-glutinous rice. The data obtained support that characteristics of rice starch are greatly affected by a trace amount of embraced lipid. The saturated amount of lipid in the rice starch might be reasonably deduced to be about 1 % or less. This value estimated from set back and maximum viscosity in amylography is in good agreement with the data obtained already.     

A Waveguide Band-Stop Filter as an Image Rejection Filter for Measurement of Stratospheric Ozone

In this report we present the performance and test observation results of a waveguide band-stop filter (BSF) as an image rejection filter for the measurement of stratospheric ozone. By using the waveguide BSF, we are able to adopt a very simple optical system and achieve a good image rejection ratio. Additionally, we are able to observe in both single sideband (SSB) mode and double sideband (DSB) mode by only changing the local oscillator (LO) frequency. We have installed the waveguide BSF into an atmospheric ozone-measuring system using a superconductive (SIS) receiver and have successfully observed an ozone spectrum at 110 GHz in SSB and DSB mode. The receiver noise temperature (SSB) and the image rejection ratio at 110 GHz are about 60 K and more than 30 dB, respectively. Because of the IF power ripple, the waveguide BSF cannot be used with a wide-band spectrometer. However, it is quite practical for narrow-band observation.     

Vertical distributions of Iodine-129 and iodide in the Chukchi Sea and Bering Sea

ABSTRACT

Currently, most Iodine-129 (¹²⁹I) present in the environment is anthropogenic; it has been released from European nuclear reprocessing plants and transported into the northern part of the Arctic Ocean via ocean circulation. This study investigates the ¹²⁹I distribution in the Chukchi Sea and Bering Sea by considering water mass structure. The range of ¹²⁹I concentration is 0.89–5.03 × 10⁷ atoms L^?1 in the studied area, which is considered to be the fallout level. ¹²⁹I was found to be distributed almost uniformly. An increase in ¹²⁹I concentration levels caused by high ¹²⁹I water inflow from the Atlantic Ocean was not observed. Additionally, we revealed the vertical distribution of iodide, one chemical form of iodine, from the Bering Shelf area to the Chukchi Sea for the first time. The range of iodide concentrations was found to be 10–157 nM. Moreover, an increasing tendency of iodide near sea bottom was observed, suggesting that iodide is released from sediments at the bottom of the sea.     

Differential Pressure/Pressure Transmitters Applied with Semiconductor Sensors

The optimum design for silicon diaphragm-type pressure sensors and that for a sensing body of the transmitters have been considered. Three types of sensors, which have different section shapes, have been developed for measuring wide-range pressure with high sensitivity and good linearity. The transmitters of the range from 0-100 Pa up to 0-50 MPa with an accuracy of 0.2 percent have been developed. For a differential pressure transmitter a three-metal diaphragm structure has been devised to protect the sensor from an overpressure. The characteristics of the transmitters are high accuracy, high reliability, and long-term stability.