Applied Mechanics and Materials Vols. 182-183

Abstract: Satellite avionics was introduced to gain mass reduction, lower cost, modular and standard equipment. Fault detection, isolation and recovery is one of the main way to upgrade the autonomy of satellites. Built-in-test is one of the most prevalent and effective fault detection method, according to the structure and characteristics of satellite avionics, the BIT of satellite avionics was designed and introduced.

Abstract: The development of all kinds of spacecrafts is much smaller and more intelligent, integration increased constantly, one satellite can accomplish more and more expectant missions by using plenty of loads. As a result, higher power, higher reliability and much smarter power distribution system is needed to satisfy the growing quantity of loads. This paper presents the power supply system which characterized by loads observation real time, software and hardware combinational over current protection, bus communication with on board computer, the system has been validated in project and the conclusion has been proved accuracy and reliability.

Abstract: A prototype of video detection system applied to traffic flow inspection is developed, which uses CMOS linear image sensor with high resolution 2K pixels and wide dynamic range as the core of imaging device. It combines FPGA with DSP as the core of acquisition and processing of massive image data. Moreover, a novel multiscale and hierarchical clustering algorithm for image segmentation is presented. Based on the theory of graph spectral, the algorithm can construct a new graph by analyzing the feature of an original image at different clustering scales, so that image segmentation can be accomplished easily to segment the image. The simulation results show that the row scan speed of this system can reach to 1000 lines per second, the resolution being 2048 pixels.

Abstract: Originated from the need in the training of sports universities, a new personal motion-measurement system via piezoelectric sensor is presented to detect step number, stride frequency, and energy consumption in motion. The motion-measurement system in training should be not only accurate in detection, but also convenient for athletes. The novel system consists of detection unit, RF-wireless unit, and display unit. Using a high-sensitive piezoelectric sensor placed within the ball or lateral side of a personal shoe, the accuracy is improved greatly. With RF-wireless, the system achieves the goal in convenience. In the display unit, detected step number, stride frequency, and energy consumption are used to evaluate the quantity of motion, so the athletics can adjust their gait immediately. Compared with existing systems, the personal motion-measurement system via piezoelectric sensor improves greatly in accuracy and convenience.

Abstract: In this paper, a SRAM array targeting IBM 130nm CMOS technology is proposed for ultra dynamic voltage scaling (UDVS) application with better immunity against process variation. A type of modified Schmitt Trigger inverter is adopted in the SRAM design, which guarantee stable operations in both superthreshold and subthreshold supply voltage regions. Testing results demonstrate that the proposed SRAM array functions well in the supply voltage range of 150 mV to 1200 mV. The optimum-energy supply voltage point is about 400 mV for proposed UDVS SRAM array. And the energy at 400 mV decreases by 62.5% compared to that at 1200 mV.

Abstract: Currently, at home and aboard many kinds of chemical gypsum processing equipment use steam as the heat source, and among them, five kinds are more mature. This article for the five semi-hydrated gypsum production equipment of thermal loss were calculated and compared. the pressure frying pan is the best choice out of the equipment.

Abstract: An experimental device is designed to control slag entrapment of molten steel with ElectroMagnetic Brake(EMBR). Mercury was taken to simulate the liquid steel flow in the mold. The factors which affect slag entrapment with EMBR are studied, such as position of magnets, distribution of magnetic flux density and submerged depth of Nozzle. Experimental results show that the posibility of power entrapped by liquid steel was smallest as magnetic flux density B=0.3T, meanwhile, it was found that F value decreases with increasing immersion depth. Indeed, the occurrence probability of the slag entrapment decreases while d=45 mm (d is distance from the centre of SEN to the centreline of magnetic core.) instead of d=25 mm. The submerged depth within 30~50 mm are suitable to the level fluctuation in EMBR conditions in this experiment.

Abstract: As semiconductor technology develops toward very deep submicron or even nanometer, power consumption per unit area increases dramatically. Scaling supply voltage into the subthreshold region provides significant energy reduction in logic circuits. However, low voltage and varies of environmental factors make it a challenge to design subthreshold circuit. This paper presents a method to modify standard cells to function well in subthreshold region. The main factors including process, voltage and temperature variables, noise and mismatch, which have more influence on the performance in the sub-threshold region than the strong inversion region. Typical static logics in the standard library TSMC65nm are analyzed by Monte Carlo analysis method when working in sub-threshold region, to find that logical failures occur to NAND V_OL and NOR V_OH before modified the sizes. After NAND's size increasing 85% and NOR's 370%, the failure has been eliminated and a good noise margin has been achieved.

Abstract: During the consecutive piercing process of metal sheets, it is very difficult to prevent the scrap-jumping completely. The scrap-jumping causes defects generation. Defective goods will be produced when processing is continued without noticing the scrap-jumping. To solve this problem,we made a die that was able to detect scrap-jumping with the load sensor and transmission-type fiber line-laser sensors for pierce processing and executed the defect detection experiment. As a result of the experiment, the newly developed load sensor was able to detect the defect in the following stamp of the scrap-jumping. On the other hand, the fiber line-laser sensor was able to detect the scrap-jumping directly before the following stamp.

Abstract: Sub-pixel positioning is a key technology in geometry measurement field. Reckoning on the low accuracy of ordinary polynomial interpolation for sub-pixel positioning method because of losing the position of edge points, an improved Sobel edge detection method is first proposed, and then is applied to the thickness measurement system of cable sheath material. The experiment shoes that the edge coordinateonthe detected by our proposed interpolation method is more colse to the real edge than the original method.