Applied Mechanics and Materials Vols. 278-280

Abstract: The article points out that it is necessary to apply condition evaluation and condition test to the electric energy metering equipment, based on the actual working condition of electric energy metering equipment. Then, the data of voltage, current, power, frequency, temperature, humidity and so on, are collected by the condition detection equipment of the electric energy metering equipment. Coupling with the errors come from the standard meter and the periodic test on the spot, this article takes the suitable data as parameters, and synthetically evaluates the influence of complicated grid operating environment on accuracy and reliability of energy metering equipment. The criteria which reflect the condition value of the electric energy metering equipment are analyzed to determine the weight of each criterion, to establish the condition evaluation criterion, and to form the condition evaluation system. According to the state evaluation results, different inspection strategies are proposed.

Abstract: This paper introduces the TPMS installation method and system composition, and on this foundation, a kind of scheme of the TPMS emitter based on the SP37 chip is proposed. Monitor use the microprocessor and TDA5230 chip to realize the wireless data receiving, and this paper details the key technology in the hardware and software design. The actual test results show that, sensitivity of the wireless data receiving of the system not less than -105dBm, and the system works stability when speed of car is 80 ~100 km/h.

Abstract: An approach of fault diagnosis of bearing based on empirical mode decomposition (EMD), sample entropy and 1.5 dimension spectrum was presented. Firstly, the original vibration signal was decomposed into a number of intrinsic mode functions (IMFs) using EMD. Second, the sample entropies of IMFs were calculated to select the sensitive IMF. Finally, the IMF containing fault infor- mation was analyzed with 1.5 dimension spectrum, The experimental results show the method can be used to effectively diagnose faults of rolling bearing.

Abstract: The main focus of our research is capturing dangerous objects when they appear under the surveillance camera again, while have performed a dangerous activities in other places. Our solution is a two-phase method, including object learning and capturing under the classification framework. The samples of objects and non-objects are collected to train a classifier with libSVM in object learning phase. In object capturing phase, all moving objects are detected by background subtraction, then are classified into dangerous or non-dangerous. To obtain a robust objects representation to illumination, scale, rotation etc. we fuse HSV space based color feature and multiple scale texture feature. The experimental results with real surveillance data validated the proposed method.

Abstract: Research on contactless power supply technique based on detachable transformer was developed, realized contactless power delivery to apparatus with no electrical connection or physical contact by the perfect combination of inductive coupling technique and power electronics,which eliminated the risk of electric shock, short circuit,or sparking. Used DSP chip and power technology had designed contactless power supply system. Experiments had showed that the system circuit could achieve contactless power transmission system control requirements. The method in solving the contactless power transmission issues has good practical value and application prospect.

Abstract: Rapid increases in the complexity of algorithms for real-time signal processing applications have made multi-processors parallel processing technology needed. This paper proposes a design of high-performance real-time bus (RTB), based on which distributed shared memory (DSM) mechanism is established to implement data exchange among multiple processors. Adopting DSM mechanism can reduce the software overhead and improve data processing performance significantly. Definition and implementation details of RTB and data transmission model are discussed. Experimental results show the stable data transmission bandwidth is achieved with performance not affected by the increasing number of processors.

Abstract: Encoder with a hexagonal lattice photonic crystal was performed by OCDMA simulation model. Filtering of photonic crystal cavity was used for encoding in spectral domain, and the distance between the dot defects was used for encoding in time domain because of its slow light effects caused by dispersion, whose time delay reached orders of ns magnitude. According to the simulation, the BER of OCDMA system with PC encoder is 10^-23, while BER is 10^-18 in the system with FBG encoder. By contrast, it is indicated that PC encoder requires strict demands on its own structure. With mismatching of encoder and decoder in receiving terminal, BER decrease to 10^-7, and the performance of OCDMA system is serious affected.

Abstract: There are a lot of ways to achieve large current pulse power supply, and the more common way is to adopt the inverter switching circuit to achieve pulse power supply. The core of the NC power supply design of large current and wide frequency pulse in SEAM is using two-stage modulation. Combined with inverter technology, DC chopper technology and NC technology, it not only can achieve the adjustability of the output pulse amplitude, but also can realize continuous adjustment of the output pulses and the duty cycle. The front stage of power supply uses DC/DC transformation circuit with the UC3879 integrated control chip as the core. With the microcontroller as the control core, the backward stage uses DC chopper circuit to achieve the NC power supply of multi-parameter adjustable output large current pulse.

Abstract: In this paper the auther made deep research on the principle and the transient process of resistance-capacitance over voltage protection circuit in different working condition during the electric locomotive running, and based on the analysis of the Circuit Transient Process, obtained the theoretic expressions of the voltage and the current of the resistance and the expression of the energy absorbed by the resistance during the working process. The research offers theoretical basis for design and improvement of the resistance-capacitance protection circuit.

Abstract: An experimental of the laser emission in a set of Ytterbium-doped silica microsphere resonator (YMCs) with various concentrations of Yb3+ ions at continuous-wave 980-nm pumping is reported. The Yb-doped silica microsphere is fabricated with single optical tapered fiber, which dipped ytterbium nitrate solution, heating of electrodes discharged.The tapered optical fiber is fabricated by using a hydrogen flame heating and step motor pulling system. The microcavity is pumped with 976 nm continue laser by a tapered optical fiber coupled to the cavity . A multimode laser emission spectrum is observed with the spectral range of laser is 1070–1185nm.