Applied Mechanics and Materials Vol. 595

Abstract: Based on the research of key technologies for achieving micro EDM process, a triaxialmicro EDM machine tool based on PMAC has been developed. The micro EDM machining tool consists of four parts: triaxial precision motion platform, motion control system, micro-energy pulse generator and CCD microscope imaging system. The hardware and software control system based on industrial control computer and PMAC has been researched. The motion control program and PLC program have been developed for precise controlling the triaxial precision motion platform. The indispensable functions for micro EDM process such as contact perception function for measurement; fast servo control strategy for short circuit and so on has been achieved. Through a number of processing tests, it is proved that the triaxial micro EDM machine tool has the ability for machining micro holes, micro slots and micro structures steadily.

Abstract: The current on-line monitoring systems for power cable junctions have some disadvantages, such as difficulty of the power supply of detecting devices, the restricted distance of data transmission and the high cost of devices. Because of the disadvantages, they are just suitable for the substation or the power plant. In this paper, a novel monitoring system which combines with the practical running situation of the power cable in the city is achieved. The monitor system uses the low consumption microcontroller C8051F020 as a data acquisition terminal, Wavecom Q2406A as data transfer equipment, and transmits the data collected to the control center by short message of GSM. The monitoring system is especially adequate to big and medium city. The equipment has been practically applied with good effect.

Abstract: Regulation activities of motion object in the computer system, and to determine whether a motion object within a specified area activity is a commonly used function of location service. The designated area on the electronic map is a closed polygon graph, namely the electronic fence. On reporting the location of the movement object coordinate relationship between the location of the polygon on calculation and analysis to determine the object is inside the fence or outside the fence. This paper introduces the electronic fence setting and discriminant algorithm implementation. The methods presented in this paper has achieved good results in practical application.

Abstract: An HV 60-V nLDMOS by adding a perpendicular-type super-junction (SJ) structure and changing pillar widths in the drain side will be investigated in this paper. In order to verify some physical parameters influences on the ESD capability, a TLP testing equipment will be used for obtaining the secondary breakdown current (I_t2) in different DUTs. In I_t2 values comparison, an SJ-nLDMOS is higher than that of a traditional nLDMOS, and as the pillar width increased the equivalent HBM value can be up to 4.799-kV. Finally, from the relationship between the SJ-nLDMOS and Ref. DUT, it can be found that an SJ structure is good for ESD discharge, as compared with the Ref. group can be increasing by 25%. In addition, the V_t1 and V_h value of various kinds of SJ-nLDMOS will decline than the traditional nLDMOS.

Abstract: This document proposes a novel two-transistor forward DC/DC converter with resonance reset. It is recommended because the duty circle is able to exceed 50% and the efficiency of the converter is higher which is superior to the conventional. The principle of operation of the enhanced configuration is illustrated and some simulation is employed to prove its practicability and superiority. Finally a 80V~140V input, 12V/8.3A output DC/DC converter prototype is founded for verification.

Abstract: The three dimensional three component (3D3C) flow field inside hydrocyclone was investigated using Volumetric 3-component Velocimetry (V3V). To improve the spatial resolution of the measurement, a refractive index matching method is used in the experiment. The three components of the velocity in the hydrocyclonic flow is measured, and the measurement produced huge amount of data, which enabled detailed analysis of the hydrocyclonic flow field. The tangential and axial is quasi-symmetric while the radial velocity is non-axisymmetric. The radial velocity is one order smaller in value than the other two component. Results show V3V with index matching is a robust method to the measurement of hydrocyclone flow field.

Abstract: It is known that Cu valence of cuprate superconductors govern transition temperature (T_c). For La_2-xSr_xCuO_y, when x = 0.15, that is, Cu valence is 2.15, the highest T_c around 40K is achieved. The Cu valence is determined both by strontium and oxygen content. So far, coulometry and iodometry have been used for determining oxygen content. However, these chemical analyses usually require experience. The purpose of this research is to develop a novel measuring method of oxygen content in cuprate superconductors with a developed dissolved oxygen sensor. Signal received from the sensor is sent to PC automatically without any external power supply. Oxygen content obtained with the sensor was newly compared with iodometry. It was found that this method is reliable enough to determine oxygen content in La_2-xSr_xCuO_y, and is called dissolved oxygen method.

Abstract: This paper presents the optimized design and Finite Element Analysis (FEA) of a bio sensor based on cubic silicon carbide (3C-SiC) for pathogen detection. Silicon Carbide is chosen due to its excellent material properties and chemical stability compared to silicon in varying environmental conditions. The desired resonance frequency is optimized using matlab and the finite element analysis is carried out using COMSOL and Intellisuite software’s. The effect of the residual stress on the desired mode of resonant frequency and the fabrication feasibility of the proposed resonator fabrication are studied using FEA analysis. The mathematical modeling of thermally actuation and piezoresistive sensing for the design resonator bio sensors are illuminated. The close agreement between the analytical model and finite element analysis verify the design of proposed bio sensors.

Abstract: In recently years, in order to exactly judge artillery capability, we should measure important parts of distortion. In this article, we research and design a non-contact three –dimension measure system of artillery parts distortion, and it can get exactly measure results.

Abstract: The principle and the realization method of the temperature measuring system which based on the temperature data acquisition chip-DS18B20 and the serial communication chip MAX1480B were introduced. Hardware principle diagram, software flow chart and main subprogram are also given. The dependability of the system was strengthened by using visualization technology and ionic smoke sensing technology.