Applied Mechanics and Materials Vols. 568-570

Abstract: In order to detect Volatile Organic Compounds (VOC) quickly and accurately, a portable electronic nose system was developed which including signal acquisition module, valve control module, embedded modules. Three sensors were used to measure methane, ethanol and formaldehyde gas. We used a three-way valve to control two kinds of gas, in order to avoid the system noise the zero reference was subtracted with the gas being tested. The system could quickly detect the three kinds VOC. The system can play a positive role in the rapid assessment of pollution in industrial parks.

Abstract: Beam width, source level and transfer efficiency of a designed transducer are tested in tank experiment. Results show that the designed transduce can meet the required resolution and penetration depth of the pipeline detection. A simulation is conducted on the received difference-frequency LFM signal. Results of the simulation indicate the qulity of pipeline detection can be improved by implementing spectrum correction and pulse compression to the recieved signal.

Abstract: At present, marine sonar instrument has been widely used in scientific research, engineering construction and environmental protection in the field of marine, but most instruments lack method of metrological verification, testing or calibration. Without standardized testing system, the quality of instrument cannot be guaranteed. This paper proposes a method to establish the system. It shows the main content of the system, especially testing platform, technical standards and testing plans in the system. The conclusion is given finally.

Abstract: The detection of motor vibration can be used to evaluate the condition of motor. Furthermore the detection of motor vibration can be used to analyze the source of motor vibration and is helpful to reduce the motor vibration. Vibration is a cause of noise,so the vibration reduction is helpful to reduce the motor noise. Through analyzing the mechanism of motor vibration, a laptop computer and LabVIEW software are used to design the experimental system. the data acquisition system of vibration signal is composed of USB5935 data acquisition card, vibration acceleration sensor.LabVIEW is used to detect the vibration signal and record the vibration and realize the spectrum analysis. Through detecting and analyzing the vibration of the permanent magnet DC motor, It is proved that the motor vibration experimental system consisting of computer and LabVIEW can fully meet the requirements of electrical machine test and fault classification research.

Abstract: Based on the metering principles of smart meter, this paper designed a sub-module function testing system which can analysis the function of smart meter. According to the principle of the bathtub curve, based on the sub-module function test prototype , we accelerated thermal stress test for the metering chip. By comparing the sampling channel data before and after the test, this paper proposed the metering chip failure analysis methods and processes, to find the cause of the failure, and thus form a “smart meter-metering chip-smart meter” failure analysis flow which can using for the smart meter.

Abstract: An accurate measurement of noise wave is the key to effective noise control in a tunnel. In this paper, an IP based audio test network is presented. This network includes 100 battery powered recorders and a WIFI network. Each recorder can acquire 2 channels of audio waves and be triggered by external signals of infrared or electrical synchronic pulse. A main control computer connects these recorders to setup parameters and collect data via the WIFI network. Sensors are reassembled to be compatible with the interface of standard sound source. Meanwhile each sensor is fixed in a sensor holder, which can be placed to any position on a plane and can be used to adjust its sensor to 0-180 degrees in both of X-Y direction. The sound source generates various signals, such as clicks, tones, and tone bursts, to help understand how the sound propagates in tunnels. This designed network is capable of acquiring multipoint sound waves synchronously.

Abstract: Magnetic latching relay is widely used in smart meter and low control energy consumption is the advantage. The quality of the meter is decided by magnetic latching relay. A magnetic latching relay performance testing system is proposed in the paper which including the main control module, auxiliary control module and the load. The three parts is connected to change the information through the network. Several magnetic latching relay samples are chose to be tested, the result says that the big current could make more damage. In this paper, the testing system can help on the quality control of the smart meter.

Abstract: Underwater acoustic transponder is widely used in marine underwater acoustic positioning system for high resolution seismic exploration. This paper introduces the structure of underwater acoustic transponder. Analysis of characteristics of underwater acoustic signal, we used Adaptive Notch Filter based on received signal detection. And the result of simulation was given.

Abstract: For more timely and accurate to monitor the real-time hydraulic pump run status and to do fault diagnosis.This paper proposes to build a pump fault diagnosis system with BP neural network,and to compose a embedded fault diagnosis vehicle terminal using ARM as its control core.The diagnosis vehicle terminal uses embedded processor S3C6410 as core hardware platform, embedded Linux as operating system, and uses Qt4 application framework to do application software design. Realization of the operating conditions of the hydraulic pump real-time monitoring, real-time fault warning and fault diagnosis function.

Abstract: Aiming at the large dimensions of state vector and attitude angle periodical change of SINS in initial alignment, The alignment algorithm was presented in initial alignment of pipeline inspect gauge system (PIGs) for pipeline fault location and geometry measurement. The state and observation equation with the attitude angle, the position of the reference point and the velocity as observed vectors is established. Combined with the UKF algorithm, variable scale UKF algorithm (SUKF) is proposed to realize the initial alignment during the pipelines detector working. Comparing with UKF, experiment results showed that the steady-state misalignment of pitch, yaw and roll were 17.5’, 6’and 5’. The results indicate that the proposed algorithm is effective for practical applications.