Field Analysis of SF(6) Gas Insulated Cables and Its Application to Spacer Design

This paper describes the spacer design for SF(6) gas insulated cables. The maximum electric stress within the cable is calculated by a numerical method, and it is recognized that the breakdown voltage depends linearly on the calculated values. Moreover, the effects of varying the shape of the spacer are made clear in this study for designing an optimum spacer

Hybrid TLC-pair meter for the Sphinx Project

The chief aims in THE SPHINX PROJECT are research of super lepton physics and new detector experiments. At the second phase of THE SPHINX PROJECT, a hybrid TLC-PAIR METER was designed for measuring high energy neutrino sources (E upsilon * TeV), searching high energy muon sources (E mu TeV) and measuring muon group (E mu 1 TeV). The principle of PAIR METER has been already proposed. In this TLC-PAIR METER, electromagnetic shower induced by cosmic ray muons are detected using TL (Thermoluminescence) sheets with position counters

A Method of Automatic Washing for Salt Contaminated Insulators

Described in this paper is a method of automatic washing for salt contaminated insulators. An average value of leakage current through the surface of the pilot insulator in a duration is measured, for this is a function of the quantity of salt adhered and its moisture content. In each cycle, the program signals give one by one the instructions on a start and an end of the integration of leakage current, a detection of the integrated value, a stop of the washing device and a reset of the integrator. The integrator consists of RC circuit and the main detecting part consists of the thyristor whose firing gate voltage is used as a reference value. If the integrator output rises above the firing gate voltage, the pulse signals are made in the signal conversion part at the same time that the thyristor turns on, which are distributed to the pump motor or the electromagnetic valve. Then the insulators on hot-line are washed all together in the appointed duration. Finally, by the various experiments this method was proved to have enough accuracy and reliability in practical use. The conclusions are summarized as follows. (1) An average value of leakage current is justified to be the detecting variable. (2) The RC circuit used as the integrator is proved to be easy in maintenance. (3) Because of the fairly short duration of the detecting action, the integrator is kept in a sufficiently safe condition under expected environment

An Asynchronous Delay Line for PAM Signal

An asynchronous delay line for PAM signal having controlled delay capability is proposed. The delay line in a cascaded chain of identical memory cells. Each sample of the sequence of the input PAM signals passes or is shifted in particular cell depending on whether the succeeding cell is empty or not. A cell is composed of two memory capacitors with the peripheral control circuits. In this paper, especially, an example of the circuit for cell is shown and its several characteristics are discussed. At the end, some experimental results are given

Spatial distribution read-out system for thermoluminescence sheets

A spatial distribution read-out system of thermoluminescence (TL) sheets is developed. This system consists of high gain image intensifier, a CCD-TV camera, a video image processor and a host computer. This system has been applied to artificial TL sheets (BaSO4:Eu doped) for detecting high energy electromagnetic shower and heavy nuclei tracks

Estimated pretreatment hemodynamic prognostic factors of aneurysm recurrence after endovascular embolization.

BACKGROUND:Hemodynamic factors play important roles in aneurysm recurrence after endovascular treatment. OBJECTIVE:Predicting the risk of recurrence by hemodynamic analysis using an untreated aneurysm model is important because such prediction is required before treatment. METHODS:We retrospectively analyzed hemodynamic factors associated with aneurysm recurrence from pretreatment models of five recurrent and five stable posterior communicating artery (Pcom) aneurysms with no significant differences in aneurysm volume, coil packing density, or sizes of the dome, neck, or Pcom. Hemodynamic factors of velocity ratio, flow rate, pressure ratio, and wall shear stress were investigated. RESULTS:Among the hemodynamic factors investigated, velocity ratio and flow rate of the Pcom showed significant differences between the recurrence group and stable group (0.630 ± 0.062 and 0.926 ± 0.051, P= 0.016; 56.4 ± 8.9 and 121.6 ± 6.7, P= 0.008, respectively). CONCLUSIONS:Our results suggest that hemodynamic factors may be associated with aneurysm recurrence among Pcom aneurysms. Velocity and flow rate in the Pcom may be a pretreatment prognostic factor for aneurysm recurrence after endovascular treatment