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XLPE power cable is widely used in grid system for its series of merits, but the fault become more and more frequent with increase of the use of cable and longer run time. In this paper, the reasons of the fault are introduced and the on-line monitoring technique of XLPE power cables is presented.

With chaotic dynamics analysis to the mechanical vibration signals of on-load tap changers(OLTC) operations, a geometric feature extraction scheme is developed for phase portrait structure based on a multi-dimensional coordinate space. The fuzzy set theory is further introduced into OLTC mechanical fault diagnosis, with a view to establishing the normal distribution membership function of every condition fuzzy set. Regarding two sample categories, i.e. single analyte sample and analyte sample sets, both principles of the largest membership and the optional nearly are used for fuzzy reasoning to finally realize mechanical fault diagnosis of OLTC.

An improved tracking method based on trajectory prediction is proposed and studied. The moving target tracking system is given and described. In order to fast and efficient tracking, a mathematical model of trajectory prediction of moving target is established. A large of experiments are carried by MALTAB. The results show that the improved method is better, improves the tracking speed and tracking precision.

Based on the self-made triaxial servo-controlled seepage equipment for thermo-hydro-mechanical coupling of coal containing gas, the experimental study on the thickness effect of composite coal and rock containing gas was carried out with the length of composite coal and rocks, confining pressure and gas pressure fixed, meanwhile change the thickness of sandstones and coal. The results show that the strain-stress curve of composite coal and rock containing gas has great identity with the typical strain-stress curve of coal or rock. The thickness effect does exist in the composite coal and rock, different thickness ratios between sandstone on top and coal have different effect on the peak strength of composite coal and rocks. When the ratio of sandstone on top to coal is close to 1.1, the extremum of the peak strength will appear more easily in the condition of the same coal thickness. The strength of composite coal and rocks will fall if the ratio is higher or lower than the ratio of thickness correspondence of the extremum, moreover, the speed of decrease is higher when the sandstone is thinner than the coal. The peak strength of composite coal and rocks varies between the strength of coal and the sandstone. The elasticity modulus of the rock-coal-rock body varies between the coal and sandstone, moreover, an extremum appears more easily when the ratio of sandstone on top to coal is close to 1.1. The poisson's ratios of composite coal and rocks are lower than sandstone, higher than coals. The results have a reference value in the support of half coal crag tunnel and the mechanical features of the composite coal and rocks containing gas.

Edge detection is the basic problem in the field of image processing. Various image edge detection techniques are introduced. Using various edge detection techniques different images are analyzed and compared by MATLAB7.0. In order to evaluate the effect of edge segmentation, the root mean square error is used. The experimental results show that no an edge detection technique works well for all types of images.

A method for determination of imidacloprid in Chinese Cabbage was established by using UPLCMS/MS. and the samples are extracted with acetontrile,and the extract is cleaned up by Florisil SPE cartridges and evaporated.Choromatographic separation was performed on a C18 column,and determined by UPLC-MS/MS.The external standard calibration curves were used for quantification. The results showed that a good linear correlation was obtained in the range of 0.005-0.1ug/mL. The limit of quantif icat ion w as 0. 008 mg/ kg .The average recoveries and the relative standard deviations were in the range of 84.9 %~92.7 % and 0.9 %~6.2 %, respectively. It is applicable to the determination of imidacloprid redidue in Chinese cabbage.

Residual amount of chlorbenzuron derived from tea was determined by UPLC-MS/MS. Chlorbenzuron was extracted with acetonitrile, purified by carbon/NH2 SPE cartridge, and then determined by ultra high-performance liquid chromatography with tandem mass spectrometry. The values o f lower limit of determination (10 S/ N) of 1.0 ug/kg-1 was found for Chlorbenzuron.Linear relationships in the range within 200 ug/L-1 was found . Recovery and precision of the method was tested by standard addition method at 3 concent ration levels. Results obtained was as follows: recovery 79.2 % - 89.6 %; RSD ( n= 6) of repeatability 0.72 % -5.85 %.It is suitable for the determination of chlorbenzuron residual in tea.

The adsorption studies of 4-chloro-2,5-dimethoxy nitrobenzene (CDNB) from aqueous solution on pyrolytic char activated by ammonium dihydrogen phosphate from pine sawdust have been performed. Several experimental parameters like initial pH, NaCl concentration, contact time solution temperature were evaluated. Solution pH within 2-7 is favor of adsorption and it is advantage of adsorption at higher temperature. Langmuir, Freundlich and Temkin isotherm models were used to fit the experimental data and Temkin model was better. The adsorption capacity was up to 33.8 mg·g1at 323 K. The process is spontaneous and endothermic and physical action is major mechanism.

The conditions for detecting residues of diflubenzuron in vegetables by ultra high performance liquid chromatography tandem mass spectrometry were studied. The target was extracted with acetonitrile for 2 min with a homogenizer. The extaction was purifide by a conditioned Florisil SPE cartridge, and then was detected by ultra high-performance liquid chromatography with tandem mass spectrometry. The average recovery was in the range from 87.8 %- 99.2 % at spike levels of 0.1, 1.0 and 10 mg/kg in vegetables, and relative standard deviations was in the range of 4.2 %-8.9 %. The proposed method is fast, simple, sensitive and accurate.

Thresholding is one of the critical steps in pattern recognition and has a significant effect on the upcoming steps of image application, the important objectives of thresholding are as follows, and separating objects from background, decreasing the capacity of data consequently increases speed. Various threshold segmentation methods are studied. These methods are compared by using MATLAB7.0. The qualities of image segmentation are elaborated. The results show that iterative threshold segmentation method is better than others.

Edge detection; Fractional differential; Medical image; Noise

Image fusion is process which combine relevant information from two or more images into a single image. The aim of fusion is to extract relevant information for research. According to different application and characteristic of algorithm, image fusion algorithm could be used to improve quality of image. This paper complete compare analyze of image fusion algorithm based on wavelet transform and Laplacian pyramid. In this paper, principle, operation, steps and characteristic of fusion algorithm are summarized, advantage and disadvantage of different algorithm are compared. The fusion effects of different fusion algorithm are given by MATLAB. Experimental results shows that quality of fused image would be improve obviously.

Edge detection is an important field in image processing. Edge detection is in the forefront of image processing for object detection, it is crucial to have a good understanding of edge detection techniques. Various image edge detection techniques are introduced. These techniques are compared by using MATLAB7.0. The qualities of these techniques are elaborated. The results show that Canny edge detection techniques is better than others.

Using logical criterion based on the characteristics of binary image, the normalized cross-correlation algorithm is improved. First, the binary of gray image is carried out. The target and the background are made a distinction between 0 and 1. Second, through the logic correlation matching, two images of the same location value equal to 1, otherwise 0. Finally, the correlation coefficient is calculated. The experimental results show that the improved normalized cross-correlation algorithm can speed up the matching, without affecting the accuracy of the matching.

Different objects could be analyzed by use of pyramid decomposition of image. Image fusion algorithm based on pyramid decomposition of image is multi-scale, multi-resolution method. Its process is completed on different scale, different resolution and different decomposition layer. Compared with spatial fusion method, fusion effects improve obviously. In this paper, principal of pyramid decomposition and process were introduced, and simulation results of image fusion based on Laplacian pyramid, gradient pyramid, ration pyramid and contrast shows that image fusion based on pyramid decomposition is improve obviously.

Edge detection and thresholding segmentation algorithms are presented and tested with variety of grayscale images in different fields. In order to analyze and evaluate the quality of image segmentation, Root Mean Square Error is used. The smaller error value is, the better image segmentation effect is. The experimental results show that a segmentation method is not suitable for all images segmentation.

The conformal coating phosphor converted light emitting diode (LED) is one of the important high power white LED. The thickness, concentration and concentration distribution of the phosphor layer has a critical influence on the LED optical performance. Previous literature mainly focus on the luminous flux of the LED. Few are involved with the relationship between the concentration and the correlated color temperature (CCT), and angular color uniformity (ACU) of LED. Based on the ray-tracing simulation, the luminous flux, CCT and ACU affected by the phosphor thickness, concentration and concentration distribution were obtained and studied. The results provide effective references for the phosphor coating process design and optical performance analysis of conformal coating LED.

Comparison analysis of linear least square method and nonlinear least square method for estimating the kinetic parameters was made using the experimental column data of Light green adsorption onto a cationic surfactant hexadecylpyridinium bromide (CPB) modified peanut husk (MPH) at different flow rate and initial concentration. The data were fitted to Thomas model equations using linear and non-linear regressive analysis, respectively and the error analysis was performed. The results showed that both methods are suitable to predict the breakthrough curves using Thomas model parameters and the nonlinear method is better.

The aim of this work was to establish a method that the residues of imidacloprid,carben-dazim and thiabendazole in fruits and vegetables were determined by HPLC.Acetonitrile was edded in the sample for extraction solvent, and using sodium chloride for absorbing water of the sample,then purified by NH2 solid phase extraction cartridge, the sample was detected by HPLC.Under the selected conditions,the detection limits of imidacloprid, carbendazim, thiabendazole were 0.002 mg/kg,0.003 mg/kg and 0.003 mg/kg respectively.Tests for recovery were made by addition of three pesticidess standards at three different concentration levels (0.1, 0.5 and 1.0 mg/kg) to the blank sample.The mean recovery rates of imidacloprid, carbendazimand thiabendazole were87.0%~99.2%,82.0%~96.0% and 80.0%~95.0% respectively , and the relative standard deviations were 0.52%~6.80%.The sensitivity, accuracy and precision of this method were able to meet the requirements for pesticide residue analysis.

To retrieve endoscopic Images efficiently, we make out several experiments using color histograms feature and color correlograms feature separately. Then integrate color histograms feature and color correlograms feature, and reduce the dimensions of combination features through using SPCA algorithm The results of experiments show that the performance of combination feature is better, and the speed of retrieval becomes higher.

A method for the determination of residues of malachite green and leucomalachite green in Chinese soft-shelled turtles (Pelodiscus sinensis) muscle by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was established. The samples extracted with acetonitrile, and clean up on a neutral alumina SPE cartridge, separated on a C18 column using acetonitrile-5mmol/L ammonium acetate as mobile phase, and then detected under multiple reaction monitoring mode.The method showed a good linearity for all the analysts over the range of 0.1-50μg/L with r20.999.The detection limits of malachite green and leucomalachite green were 0.10 and 0.12μg/kg respectively. The recoveries ranged from 84.9 % to 93.8% at three spiked concentrations with the relative standard deviations lower than 5%. The results shows that this method has the advantages of easy to operate, fast to perform,with high sensitivity and accuracy, and it is suitable for detection of residues of malachite green and leucomalachite green in Chinese soft-shelled turtle (Pelodiscus sinensis).

hydrophobicity ionic liquid [bmiPF6 mix with PdCl2 is used as catalyst and reaction medium to form biophasic liquid reaction system to catalyst mixed gas of PH3. FT-IR is used for the conformational analysis of [bmi PF6 monomer and Waters 431 chromatograph for the products of purified reaction. The relationship between temperature, oxygen concentration, the amount of substance of PdCl2 and PH3 purification efficiency have been investigated. The results show that purification efficiency remains above 99% in 300min. There is no obvious increase of purification efficiency with O2 content increased. The optimum conditions of catalyst system are: [bmiPF6: PdCl2=1:0.056 (molar ratio), temperature of 70°C between 30~70°C. The reaction products contains PO43- in the aqueous phase by instrumental analysis.

The 3-105 half isolated island fully mechanized caving face in Tengdong coal mine which in complex geological and high temperature condition, has a spontaneous combustion feature that is different from normal advancing mechanized caving face, such as slowly advance speed, stress concentration and air leakage of inside-impending gob. To overcome the dangerous possibility of spontaneous combustion between the roof coal seam inside-impending gobs, small coal pillar and adjacent gob of half isolated island fully mechanized caving face, analysis spatial structure of overlying strata roof and spontaneous combustion characteristics. Based on the result of pressure can be measured and tracer gas test of air leakage channels, determine the potential air leakage areas. The MEA plugging wind material is pumped into roadway and SPA-4 plugging wind material is spray around known air leakage or high temperature area to eliminate the hazards of spontaneous combustion of the potential danger zone, and protects the safe mining of the working face.

In view of high energy consumption situation in the apparel industry in the background of cyclic economy, the author conducts technical experiment for clothing style change according to transformation design of clothing structure elements, and establishes the environmental protection philosophy of enabling raw materials for one garment to satisfy the function of raw materials for two or more garments. This not only maximizes the energy efficiency of clothing materials, but also optimizes life cycle of products, and accordingly promotes the energy-saving and environment-friendly eco-civilization construction in the apparel industry.

A novel rectangular vectorization method which uses for auto-forming board based on the feature analysis on a great many of shear wall structural design charts is presented. The constructional design drawing was firstly deconstructed into elementary figure unit which contains lines and rectangular angles. These split functional cell were secondly vectorized by restricting straight line so as to reorder and reclassify these essential structural parts. Finally, the components made for the forming board were obtained from the identified cells combined with the shear well angle’s location. This auto-forming board technology has been applied in cast-in-place concrete practices and the results demonstrate that this method and technology can accurately identify complex constructional drawing constitution of building and raise substantially the efficiency of auto-forming board for building construction. This method also provides the key technique support for smart construction technology.

This paper frame structure stair design problem, the stair to participate in overall structure calculation and setting sliding connection are discussed.

The piston stopping position after engine shutdown is the key factor for idling stop technology, the next starting process of the engine is decided by the piston position. The piston stop position detecting system is designed based on the gasoline direction injection 4G15. The system is composed of a high-speed data acquisition card, two optical sensors, an encoder, a cylinder pressure sensor, an amplifying circuit and an industrial computer. The state signals of the crankshaft and the camshaft are collected by the detecting system, the distribution probability of piston position is obtained. The crankshaft reversal after shutdown and the crankshaft position can be detected and judged.

The objective of this study was to propose a method that the residues of avermectins (Abamectin, Emamectin Benzoate, Ivermectin, Eprinomectin and Doramectin) derived from the food plant were determined by UPLC-MS/MS. The avermectins were extracted with acetonitrile, purified by Alumina B or GCB/NH2 SPE cartridge, and then determined by ultra high-performance liquid chromatography with tandem mass spectrometry. Tests for recovery (Recovery rate: 80.6%～99.8%, RSD's: 0.22%～6.4%) were made by addition of avermectin standards at three different concentration levels (4, 20 and 100μg/kg) to five kinds of food plant as matrixes. The sensitivity, accuracy and precision of this method were able to meet the requirements for pesticide residue analysis.

Restrictors are one of core parts in aerostatic systems. A special multi-microchannel aerostatic restrictor is designed and developed, and the air film thickness is measured by the capacitive measuring method. The mathematical model of capacitance and air film thickness is carried out, capacitances of specific air film thickness are calculated, air film thickness of the multi-microchannel aerostatic restrictor with the overall diameter is measured, and error sources processed and analyzed. Results illustrate that errors between the theoretical calculations and the experimental data are less than 13%, this proves the correctness of the mathematical model as well as the effectiveness of the capacitive measuring method applying for the air film thickness measurement of the aerostatic systems.

Concurrent engineering has been used in many OEMs in order to face up to the fierce competition situation. Modular development teams develop common modules which are applied in the same platform-based variants and its product family in order to save design costs and reduce development time. The R&D department should construct a concurrent engineering team to quicken the pace of new product development and to ensure product quality by means of open-loop and close-loop cycle, and frame a platform to frequent communication and quick decision for the concurrent engineering team.