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Silicone rubber (SIR) is widely used in the field of high-voltage cable accessories insulation due to its excellent electrical properties. However, according to statistics, in 2016 alone, there were many cable accidents at home and abroad, among which cable accessories failure accounted for 85.5%. In order to fit closely with the cable, the high-voltage cable accessories adopt the installation method of pre-expanding and maintain the expanding state in the long-term operation of the cable. The silicone rubber is deteriorated by the circumferential mechanical stress, which is easy to lead to electrical tree and finally cause breakdown fault. At present, because the steel needle electrode is easy to form gas gap with the insulating material which results in the error of electrical tree experiment under the large deformation, the research on mechanical stress is mainly focused under 30% deformation, which is far less than the actual diameter expansion ratio of 45%. In this paper, in order to approach the actual working state of the insulation material of accessories, the initial voltage and morphological characteristics of silicone rubber electrical tree under large tensile ratio of 0%, 25%, 45% and 60% were studied. In order to avoid the stress concentration at the tip of the traditional steel needle electrode, a new semi conducting needle electrode was designed and successfully manufactured, and a real-time observation system of electrical tree under power frequency was built. The results showed that the initial voltage of semi conducting needle electrode was higher than that of traditional needle electrode under the same tree initiation condition. With the increase of tensile mechanical stress, the initial voltage decreased from 15.30kV to 14.33kV, and the electrical tree tended to grow in the direction of stress application. Combined with the test results of Differential scanning calorimetry and Thermogravimetric Analysis, it can be seen that the "melting point" and the temperature of maximum thermogravimetric rate increased first and then decreased with the increase of tensile ratio. At low tensile ratio, small-scale fracture of SIR molecular chain occurred, and the amorphous region increased. At high tensile ratio, the number of broken molecular chains increased. On the whole, the physical crosslinking of silicone rubber was destroyed, some molecular segments cracked, the free volume inside the material became larger, the electrical tree was more easily induced, and the electrical tree resistance of the material decreased.

Named Entity Recognition (NER) systems are often used as the first step for most of Natural Language Processing (NLP) tasks like question answering, information retrieval, etc. In our paper, the fine-grained NER for entertainment news is the task of identifying nine named entities like person, TV, music, etc. It is challenging not only because of inherent noisiness but the data contains numerous informal abbreviations. We proposed a novel adversarial multi-task learning framework by employing two auxiliary tasks named Part-of-Speech (POS) and Chinese Word Segmentation (CWS) together with a primary NER task. Our model can use task-shared features better and filter task-specific information of CWS and POS. To the best of our knowledge, our work is the first study that incorporate POS and CWS into fine-grained NER task in entertainment news

In recent years, several cases of 220 kV silicone rubber cable joint failures have been reported in China. The faults were hypothetically attributed to air gap at insulation-semicon interface and electrical tree in insulation. It is thus important to gain a better understanding on the influence of these types of defects on the electric field distribution. In this paper, we present the simulation of 220kV cable joints under different defected cable joints. The parameters set in the simulation were based on the experimental results obtained by testing the relative permittivity, dissipation factor, volume resistivity of the silicone rubber of the defected cable. The breakdown strength of the silicone rubber was also tested to investigate whether or not the theoretical electric field obtained in the simulation is higher than the breakdown strength. The results show that the electrical field concentrates at the surface of high voltage shield and the interface between the semi-conducting stress cone and cable insulation. Air gap and electrical tree distort the electric field distribution. The strength of the electric field at the defect is much higher than the breakdown strength of silicone rubber. Therefore, defects present in cable joint are supposed to accelerate the thermal ageing of the cable insulation and hence promote the growth of electric tree which will finally lead to unexpected cable failure.

Pressboard, a common kind of electrical insulating material, is widely used in the gas insulator transformer (GIT). While a GIT was in operation, the properties of the pressboard changed under the influence of sulfur hexafluoride (SF 6 ) and heat. In this paper, pressboard was subjected to an accelerated aging test in SF 6 atmosphere at different temperatures for varying durations. In the research several tests were conducted, including thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), a bending test, scanning electron microscopy (SEM), a dielectric properties test, and a polymerization degree test. These were carried out to research the heat stability, mechanical properties, dielectric properties, and microstructure of the pressboard at different stages of aging: The reasons for these changes could be discovered by analyzing the results. The results showed that thermal degradation of cellulose at high temperature was the main aging factor in pressboard during the thermal aging process in a SF 6 atmosphere, which also caused deterioration in the heat stability of pressboard. The mechanical properties of the pressboard deteriorated as thermal aging increased, while dielectric properties increased which were indicated by the decrease in electric inductivity and dielectric loss, and the increase in electrical resistivity. The main causes for these changes were the fracturing of the main chain of the cellulose molecules and a decrease in polar groups, such as hydroxyl, which caused a decline in the hydrophilia of the pressboard. As a consequence, the water content and the number of hydrogen bonds in the materials decreased, leading to structural degradation and a decrease in polarity of the pressboard.

This paper presents a non-photorealistic rendering method combining fuzzy color models with mosaic rendering to emulate the fuzziness of color usage. The method first triangulates the source image based on its local details, to emulate artists' methods of observing and analyzing the image structures. Then, it converts the color from the source image to obtain the fuzzy color for every triangle. Finally, it renders the triangles by a customizable fuzzy coloring strategy. The results show that the proposed method achieves good simulation of different artists' coloring strategies. Using the rendering application based on the proposed method, the user can quickly achieve many renderings in different coloring strategies by our mosaic rendering prototype.

XLPE, which exhibits good electric insulation and mechanical properties due to its chemical crosslinked structure, has been used as modern extruded cable insulation materials for nearly 60 years. However, XLPE cannot be easily recycled in the end of its lifetime so that there will be a big issue in dealing with XLPE craps. New polyethylene blending materials, which have suitable recyclability and comparable dielectric and mechanical properties with XLPE, is gaining increasing attention. In this investigation, dielectric behaviors of a new blending material have been compared with XLPE. This new blend contains liner low-density polyethylene as matrix and high-density polyethylene as blending. XLPE, pure liner low-density polyethylene and highdensity polyethylene are also prepared and tested for comparison. DC resistivity, permittivity, loss tangent and breakdown strength of these materials are measured at 30°C, 45°C 60°C, 75°C, 90°C respectively. The temperature dependence of dielectric properties for these systems has been measured and discussed. The results show that temperature dependence of DC resistivity, permittivity for these materials present the similar tendency. However, the new thermo-plastic polyolefin blends show lower loss tangent and higher breakdown strength than XLPE especially the loss tangent at high temperature. The results suggest that the blend has a great potential to be used for extruded cables.

Since 1960s cross-linked polyethylene (XLPE) has become one of the most important insulation materials for extruded cables based on its excellent comprehensive performances including electrical, mechanical and thermal properties. However, the disadvantages of high level energy consuming in manufacturing process and hard to recycle at the end of lifetime have been non-negligible economic and environmental problems. Therefore, developing new insulation materials which are recyclable and low energy consuming is imperative. In this work, we study the mechanical properties of the binary blend system which contains high density polyethylene (HDPE) and linear low density polyethylene (LLDPE). The samples with different proportions are blended with rheometer and shaped in the specific moulds with press vulcanizer. The large-stress properties have been characterized by tensile tests and cantilever beam impact tests. The results show that the 70wt%LLDPE-30wt%HDPE blend exhibits the optimal mechanical properties with relatively high mechanical strength of 31MPa in tensile strength and 829% in breaking elongation (higher than XLPE) and low modulus of 450MPa (higher than XLPE) in blending system. Furthermore, the small-stress property of 70wt% LLDPE-30wt% HDPE blend is measured by dynamic thermo-mechanical analysis (DMA). In addition, the creep property of 70wt% LLDPE-30wt% HDPE blend is even better than XLPE below 130?. Therefore such a blend exhibits good mechanical behaviors and may find its potential application as an insulation material.

In this paper, XLPE/porous-ZnCO3 composites are prepared by melt blending method. The influences of partical content on the structure and performance of the composites are studied. Scanning electron microscopy was used to observe the particle shape of porous-ZnCO3. The differential scanning calorimetry(DSC) result indicates that porous-ZnCO3 is acting as nucleating agent to reduce the size of spherulite and then the degree of crystallinity. Thermal gravimetric analysis(TG) results show that the thermal stability of XLPE/porous-ZnCO3 composites was improved. Electrical experiments show that the dielectric constant of the composite increase with the porous particles content, but decrease with temperature.

In this paper, a series of montmorillonite/Cross-linked polyethylene nanocomposites containing different compatililizer (vinyl acetate copolymer (EVA) or ethylene-ethyl acrylate (EEA)) are prepared by melting blending method. The influence of compatibilizer on the dielectric property of the nanocomposites is studied. DSC is used to study the melting and crystallization behaviors of nanocomposites with and without compatibilizer. Dielectric spectrum of the nanocomposite is tested in room temperature. Dielectric constant and loss factor of different nanocomposites in wide frequency range are analyzed and the dynamic polarization behavior is discussed by the universal relaxation law (URL). Based on the structure characteristics, the effect of compatibilizer on the nanocomposite polarization is obtained.

The principal component analysis method is usually used for fault detection under the steady conditions, however, when system works under the non-steady conditions, the false alarm rate and the missing alarm rate, tested by the T2 control limit, are so high. The main reason for this situation is that the sampled data is accord with normal distribution under the steady conditions, whereas the data does not satisfy normal distribution under the non-steady conditions, but T2 control limit can only detect fault effectively for the data conforming to normal distribution. So this paper firstly analyzes the characteristics of the periodic non-steady conditions and then puts forward a normalization PCA (NPCA) model according to the precondition of effective detection under the T2 control limit. This model deals with the measured data for normalization data based on the longitudinal standardization, and then uses T2 control limit to detect fault. At the end, it is applied to wind power generation system, and the results verify the effectiveness of the model.

The principal component analysis method is usually used for fault detection under the steady conditions, however, when system works under the non-steady conditions, the false alarm rate and the missing alarm rate, tested by the T2 control limit, are so high. The main reason for this situation is that the sampled data is accord with normal distribution under the steady conditions, whereas the data mostly does not satisfy normal distribution under the non-steady conditions, but T2 control limit can only detection fault effectively for the data conforming to normal distribution. So this paper firstly analyzes two characteristics of the periodic non-steady conditions and mathematical theory and Q-Q figures have verified the characteristics, then a normalization PCA (NPCA) is proposed. Finally it is applied to the system of the motor cyclical process and alleviating the load, the test result is good and can verify the effectiveness of the model.

This article combined ECA rules with Email transfer mode to achieve the dynamic approval flow. The dynamic approval workflow is realized in ASP.NET by the description of the approval and the optimized design of database, which solved a business problem of dynamic approval in network.

TasA protein of Bacillus subtitlis was reported to have a broadspectrum of antibacterial activities. The TasA open reading frame (ORF) was PCR-amplified from A6, and cloned into pMD18-T. Sequence analysis of the clone indicated that the TasA ORF consists of 786 nucleotides, and shared 99.24% homology at nucleotide sequence, and 100% identitiy at amino acid sequence between it and the published gene TasA (corresponded with 143163∼143948) from Bacillus subtilis (Accession No:Z99116). The nucleotide sequence variations were base transitions (A/G or C/T substitution), and occurred on their third base of the codons in the ORF. The second structure and the amino acid sequence of TasA protein were predicted by using the software (http://npsa-pbil.ibcp.fr/cgi-bin/secpred_mlr.pl). In order to understand the molecular function of TasA protein, the TasA gene was cloned into expression vector pET-TasA, and expressed in E. coli BL21. A unique 33kD fusion protein product was detected by SDS-PAGE, which indicated the TasA protein was expressed correctly in E. coli BL21.

In this essay the DC resistivity and high field conductive properties of nano metal/polymer composite are studied. It shows that if adding little small-sized Ag particles, the resistivity of composite increased obviously in comparison with pure epoxy resin, and the increasing of resistivity is related to the size and content of Ag particles, and the performance of polymer. High field conductive property of nano Ag/epoxy resin composite is studied. It is found that the capacitor network, which is formed by nano Ag in epoxy resin, has evident Coulomb blockade effect, and the conductance is obvious restricted in the composite, the slope of current density curve under log-log plot is less than 1; the comparative big nano metal, which tend to aggregation, will appear the space charge limitation current properties. It shows that the nano Ag particle has certain effect on the trap of composite, in high electric field a rather large space charge limitation current will appear because of the filling of the trap in composite.

Partial discharge (PD) is one of the main reasons for insulation degradation of power transformer, ultrasonic method has attracted great attention for its anti-interference ability and convenience of location for partial discharge measuring, based on an improved genetic algorithm, an ultrasonic-ultrasonic locating method which takes the equivalent velocity of ultrasonic as a variable is introduced in this paper. Besides, a gap discharge and a surface discharge model is designed, by comparing the measuring data of electric PD detection and ultrasonic measurement for them, the relationship between ultrasonic intensity and apparent discharge magnitude is also discussed.

Nano-Ag can be prepared through ultraviolet radiation reduction reaction and then the influence on nano-Ag particles by protecting agent, intensity of radiation and mixture ration is studied. The TEM result shows that Ag particles are dispersed evenly and the particle size is about 20 nm. Nano-dielectric with nano-Ag in epoxy resin is prepared successfully. The dielectric property of the composite is discussed. The result is that resistivity (rhov) and breakdown electric-field intensity (Eb) in room temperature of the composite are improved; the dielectric loss (tandelta) is reduced and the permittivity (epsivr) changes little. It can be seen that the dielectric property of base polymer material is improved by adding nano-Ag particles. This phenomenon is explained by Coulomb block effect

The corrosion is studied under the wet and grimy condition by acceleration test in this paper, and the lasting time is equivalent forty years of natural conditions. As a result, the main corrosion mode of metal parts in high voltage direct current is electrochemical corrosion. The rapidity of corrosion is relative to the leakage current and the processing technique. It is necessary to evaluate the corrosion resistant capability of metal parts in those support insulations which are assembled in heavy grimy areas or with high leakage current.