Applied Mechanics and Materials Vols. 303-306

Abstract: To determine the individual values of the two strain components by separate principal strains, a theoretical model of strain separation by oblique incidence with a new luminescent photoelastic coating configuration is presented. Considering the non-strain related refraction effect included in the total optical response at oblique incidence, the small incidence angle technique for simplifying the post-processing complexity is given. To affirm the validity of this strain separation method based on small oblique angles, the signal-to-noise ratio for providing sufficient signal intensity has been theoretically analyzed.

Abstract: This paper introduces the use of self-made CCD camera system for acquiring the information of self-made controller strip on specific areas of a printed page. Through mask equation and the conversion model, established by three-dimensional cube and the matrix methods, whose data comes from the transformation of RGB information to XYZ tristimulus value, we can gain the data to test the quality of the printed materials, such as the characteristic colors’ Lab values, dot gain, print contrast, trapping rates, and comparing with the standard, we can also acquire the tutorial information of the trend towards the adjustment of the ink amount in ink zone or the comprehensive evaluation report of the quality of the printed materials. This method proves as an effective approach to the integrated quality assessment for a full-page detection system, and has a bright future of wide application.

Abstract: The explosion-proof monitoring system of oxygen content usually is used situates in an explosive mine gas explosion monitoring site, the spark and thermal effects in its monitoring circuit are likely to form dangerous explosion source. Based on the intelligent control technology of MCU(msp430) and radio data transmission technique, this mine oxygen content monitoring system was designed according to the highest mining explosion-proof standards, so that its monitoring circuit can meet the intrinsically safe explosion-proof requirements. That is, when the hardware circuit of a explosion-proof monitoring of oxygen content was designed, the factors for limiting the heat source energy with forming the spark and thermal effects must be considered seriously.

Abstract: A portable acoustic-electric detection system for GIS partial discharge is developed. This system integrates both high and low-speed data acquisition devices, and is capable of multichannel joint detection of ultra-high-frequency and high-frequency current as well as ultrasonic signal generated during the GIS partial discharge process. The software of this system is developed based on LabVIEW. It can successively capture, acquire and store the pulse waveform of partial discharge, calculate the phase of discharge pulse and realize time-frequency analysis and amplitude-phase distribution analysis of PD signals at the same time. By calculating the time difference of multi-channel ultra-high-frequency (UHF) signals and of PD ultrasonic signals or the time difference between the two, the system is able to locate the PD source. This system has been applied to on-site partial discharge detection of 220kV and 500kV GIS substations, and the test results have verified the performance of the system.

Abstract: Dry-type power transformer was used widely because of its advantages. But unplanned outage effect to construct a strong intelligent power grid because of various stress. Dry-type power transformer’s fault repair time is long and impossible to repair. So it is very important to realize state maintains of dry-type transformer through state monitor and diagnosis. Based on current diagnostic methods, this paper proposed using self-organizing neural network to realize dry-type power transformer the key point temperature parameters of grading evaluation and then to realize the real-time state evaluation and analysis of failure causes. Study results to prolong the dry-type power transformer life and its design production provide theoretical guidance, in order to reduce and avoid dry-type power transformer failure.

Abstract: In order to solve the problems of flow measurement and to obtain the sectional velocity distribution of open channel, the FLUENT simulation method was adopted. The velocity-area method based on the sectional velocity distribution was introduced, and the flow measurement equipment of open channel was also designed. The experiment result shows that the error of the method is less than 1%.

Abstract: Quality evaluation of agricultural and food products is important for processing, inventory control, and marketing. Fruit surface defects are important quality factors for the jujube industry, especially for high quality jujubes such as Xinjiang red jujube. This paper presents the development and test results of a machine vision system for automatic jujube surface defects detection. Unlike other near-infrared spectrometric approaches, the developed machine vision system uses reflective near-infrared image to evaluate jujube quality by analyzing two-dimensional images. Near-infrared image, vision algorithms and a variety of operational details of the system, including cameras, optics, illumination, and fruit carrier are presented. The complete machine vision system has been built, and the experimental results show that the designed machine vision system is feasible to detect the defects of jujubes.

Abstract: The process of building environmental information perception can be constructed with wireless sensor network (WSN) expediently. A WSN based information acquisition system for building running environment is described in this paper. The CPU of host computer in the system is Loongson2F and wireless nodes in the system are implemented as Telsob nodes. Because the price of wireless node is low, the hardware cost of the desired system is decreased evidently and the security of the desired system is enhanced because the CPU of the host is native. With those features, the application scenario of the desired system is extended widely. To verify the suitability of the using of Collection Tree Protocol (CTP) in construction of the WSN in the desired information acquisition system, the performance of the CTP based WSN deployed in public building space for environment information acquiring are tested and solutions for some key problems in the construction and the maintenance of the CTP based WSN are given in this paper too.

Abstract: This paper proposes a novel approach to diagnosis the faults in analog circuits based on Volterra kernel and ant colony-particle swarm algorithms. In the analog circuit fault diagnosis, we use the Volterra kernel as the feature vector which makes the characteristic vector lumped Euclidean distance in serials of fault states under the same excitation signals as the fitness function. And the optimized the parameters are used to stimulate the multi- frequency sinusoidal signal. The AS-PSO hybrid algorithm is performed to find the best excitation signal parameters. Experimental results show that the proposed approach can achieve good faults diagnosis results.

Abstract: The thermocouple automatic verification device is constructed of Advantech PCI-1716 bus data transmission automatic calibration multi-function data acquisition card, USB-4718 eight-channel thermocouple input module, JKH-C series SCR phase-shift trigger, PC machine as hardware and the U.S. National Instruments (NI)Labview as software development platform. According to temperature test point determined by thermocouple verification regulation, the device controls the temperature of calibration furnace, acquires the standard and the thermocouple millivolt values automatically and calculates the error at each testing point in line with its measurement data processing formula, realizing the functions such as visual operation interface, test data saving and verification certificate printing. Device accuracy: potential measurement error is no more than 0.005. Resolution: potential is 0.01μV. Temperature control accuracy: error deviating the test temperature is no more than ±5°C when testing it. Temperature stability: the constant change is no more than 0.2°C/min in its testing process. The thermocouple calibration uncertainty is better than 0.7°C and the repeatability error is less than 0.25°C.