Applied Mechanics and Materials Vols. 401-403

Abstract: This paper presents a fiber different pressure sensor based on intensity modulation,This sensor is composed of number of pressure sensing probes, the form of each probe is used to the fiber axis symmetric distribution, Using the analytical method to establish a mathematical model of light intensity modulation function M, this mathematical model showed a ratio of the received light intensity and entered light intensity, the ratio is mainly composed of the effective receiving area S and the reflected light cone end diameter R, finally using the simulation method to calculate the output light intensity ratio curve of the receiving fiber when the distance parameter was changed, and imposed a range of pressure P on the elasticity of thin slices, the results showed that the value of has little effect on the sensor measuring range. Finally, done the level monitoring experiment in one container, and obtained that the change of output signal and liquid level had the same trend.Studies have shown that, by this structure of the differential pressure sensor designed, can be achieved for different pressure range and accuracy detection.

Abstract: In order to make the actual state of the bridge into the ideal state of maximum, we make real-time monitoring in the key parts of the bridge, and adjust to the design of the data to ensure the safety and reliability of arch bridge in the course of construction. Combined with the construction monitoring of the Sihe Bridge, this paper introduces the main bridge construction process on the large span tied arch bridge. Based on the construction monitoring of Sihe Bridge, this paper introduces the main contents and methods of monitoring point location, monitoring control of construction process, and discussed the construction monitoring technology of long-span X-style tied arch bridge.

Abstract: This paper proposes a new one-shot grayscale structured lighting scheme to obtain depth data fast. Its key idea is to code the pattern using modulated sinusoidal gratings along two axes. The features used for matching are the fringe central lines of the vertical grating. The correlation of the intensity profiles is used to measure the similarity of features. Experimental results using a vision system with two cameras and a projector show that the proposed scheme is effective and efficient.

Abstract: Traditional water test method has the advantage of locating leaks can be found, the disadvantage is inefficient manual detection, labor-intensive, can not be automated testing. By analyzing pneumatic and PLC control were introduced, pneumatic system of the detection device was designed, combined with operation process of the pneumatic circuit PLC control system was designed. Through the PLC control solenoid valve opening and closing, thereby control the implementing agencies of the pneumatic circuit, the device complete each course of action to achieve the test. Application of the system has maintained the advantages of the water detection assay, achieved a semi-automated detection, increased the detection efficiency, reduced labor intensity, and easy to operate.

Abstract: A multi-point wireless pulse measuring system based on CC2530 is discussed. By using a PVDF pressure sensor, human pulse signal is picked up. Then a filter circuit and a amplification circuit are designed to obtain accurate and stable signal. Based on single-point pulse measuring, multi-point wireless pulse measuring system based on CC2530/ZigBee network is constructed, and a data managing system based on LabVIEW is designed to deal with these signals. Finally, experiment is provided to show the effectiveness of the proposed scheme. Keywords: Pulse; CC2530; ZigBee; LabVIEW; PVDF

Abstract: Aiming at the small coverage of shore-based AIS and complicated structure of space-based AIS, airborne AIS is chosen to increase the coverage effectively. This paper gives the calculation method of the maximum transmission distance, and then establishes the detection probability model of the airborne AIS. The relationship between reporting interval, ship densities and detection probabilities is established. At the end of the paper, simulation results of the model are given.

Abstract: A method for moving target classification in road monitoring based on multi-feature fusion is presented in this paper. In this method, connected component labeling and merging combined with morphology are used to achieve the target extraction. Static features in moving target are extracted. To improve the low classification accuracy, a dynamic feature, lower thirds aspect ratio variation (also named as LTVar), is proposed and added. The recognition ratio obtains the relative increasing of 3.1% compared with the static features.

Abstract: A recognition method based on metal magnetic memory and wavelet entropy theory is proposed to detect cracks in metal workpiece. First, wavelet decomposition is performed to magnetic induction signal, and wavelet entropy is introduced based on soft threshold in wavelet transform to reflect the distribution feature of signal energy. Then the threshold of high-frequency component is determined self-adaptively due to different wavelet entropies of the signal at different decomposition scales, thus extracting useful information effectively and determining the position of the defect. Experiment result shows that the crack could be pinpointed based on characteristics from wavelet entropy theory, thus having an excellent application prospect in the life evaluation of metal defect.

Abstract: Aimed at problem that technical conditions parameters of recoil mechanism need to be monitored during maintain and guarantee, method on condition monitor method for tank gun recoil based on vibration signal is brought forward and monitoring platform is designed. Accordingly, monitoring technical conditions change of recoil mechanism is realized and technique support is provided for usability evaluation of key parts of tank gun.

Abstract: Speed monitoring system of ship’s main engine was completed a few of functions such as ship speed signal acquisition. The smsm system can also count, analysis and process the signal through the master ecu, and display the host speed value on the lcd circuit. When the rotational speed of the ship’s main engine is different to the present speed, it’ll output a control signal to adjust the engine throttle . When the ship's speed exceeds the speed limit, The smsm will alarm by sound and light.