No abstract

No abstract

No abstract

Near-infrared absorption spectra of NO, N02, and N20 were observed in the wavelength region between 1.2 and 1.9 ii m using a high-resolution Fourier-transform spectrometer, and we have obtained precise absorption data which are useful for Tunable Diode Laser Absorption Spectroscopy (TDLAS).Furthermore, the NO and N2O were detected by means of TDLAS method for the first time using InGaAs-DFB diode lasers which were designed to access absorption lines at wavelengths of 1.798 and 1.766 /2 m, respectively.

A spool valve as a flow direction control valve has usually been used in a hydraulic system. In recent years, some hydraulic actuator systems need high accuracy control of the spool valve in order to control the delivery precisely. For the reason, it is very important practically to know dynamic motion of the spool. To analyze the dynamic characteristics of the spool valve, it is necessary to consider the dynamic motion of the spool. Springs, solenoids and working fluid, which is pressurized by the pump in the circuit, support the spool. The motion of the spool is governed complicatedly by pressure force, flow force, electromagnetic force and mechanical spring force acting on itself. As a result, it is difficult to analyze the dynamic motion of the spool, and therefore, any commercial code to calculate the dynamic characteristics of the spool valve dose not exist at present.Final target of this study is to develop numerical code to predict precisely the dynamic motion of the spool valve. As the first step, dynamic characteristics of a spool valve coupled with electromagnetic and mechanical effects have been conducted in the present paper. KEY WORDS