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In this work, 1200 V SiC JMOS devices with different Wsch (2 μm, 2.5 μm and 3 μm) are fabricated. The single unclamped inductive switching (UIS) tests under different Vgs_off (-5 V and 0 V) are carried out to investigate the avalanche capability. The avalanche robustness among various Wsch under same Vgs_off is also compared and analyzed by simulation. The different failure mechanisms between different Vgs_off are studied by failure analysis and simulation. The method of improving avalanche ruggedness of JMOS is proposed.

In this paper, we investigated the porosities and their formation mechanism in the nickel-base superalloy powders, which were prepared by electrode induction melting argon atomization and divided into four particle size ranges: d＜60μm, 60μm≤d＜120μm,120μm≤d＜180μm, and d≥180μm. Firstly, the distribution of porosities in the powder were observed by Zeiss electron microscope. Secondly, the number and size of porosities in different particle size range were counted. Finally, the formation mechanism of the porosity was analyzed in details. The results show that the porosities are mainly distributed at the edge and center of the powders, and the size increases with the increase of the powder size. the porosity varies from a few microns to dozens of microns. the biggest pore size in the powder is approximately 120μm.There are no obviously porosities found in powders when their diameters are less than 60μm. While the porosity appeared as the powder diameter is more than 60μm. In addition, the proportion of the powder with porosities also increases with increasing powder size. When powders size is more than 180μm, the proportion of the powder with porosities reached about 91%. In general, the formation of porosities in powders are mainly ascribed to two reasons. the first one is a portion of argon was enclosed by the metal films during the spheroidization; the second one is the metal droplets uneven shrinkage during the solidification.

This paper for wine evaluation, through processing the two sets of data collected, analyses the results of the two wine sommelier evaluation whether there are significant differences, and determines the critic credibility of the results of the two sommelier wine critic credibility. Then, on the basis of sommelier wine critic results of the two groups, through statistical analysis for the physical and chemical indicators of wine grapes, we get a major physical and chemical indicators that influence wine grape quality, and then wine grapes are be graded.

Horizontal casting machine is one of the key equipments of the continuous casting production line for aluminum ingot, the stable running of transporting chain has direct effects on the surface roughness of the finished aluminum ingots and the technical data of the machine. The casting machine supports are the main carriers of molds,the drive chain and other components,which have long-term work in hot and humid environment and easily leads to the running stationarity of transporting chain reduced. So in order to improve the operation stability of the transporting chains of the casting machine and the surface roughness of the finished aluminum ingots, the sequential coupling analysis methods of thermal structural coupled analysis module of the finite element software ANYSYS is used to analysis of thermal deformation and temperature field simulation for the casting machine supports, and determine the size and distribution pattern of the thermal deformation and thermal stress of the casting machine bearing parts,the simulation results provide a theoretical basis for new product design and development work in the selection ,structure and layout optimization.

Based on the theory of finite element and modal analysis theory, analysis of static and dynamic characteristics of the lathe bed has been done. The static displacement contours and mode natural frequency and displacement contours have been given to realize the structure optimization of lathe bed of high-speed horizontal machining center. It is shown that the bed has good static stiffness and natural frequency and the deformation of lathe bed mainly occurred in the tray conversion mechanism and the cutter location. The deformation of processing work area is small and has certain light weight space, which lay the foundation for the lightweight design of the bed.

It is important to monitoring the fine particles (PM2.5) in atmosphere as it threatens the public health all over the world. But the existing concentration measuring devices have shortcomings in speed and range. A novel fine particle concentration measuring system based on the ultrasonic attenuation was designed in this paper, which could help to solve the problem. Firstly the mechanism of ultrasonic attenuation in dust cloud was studied to verify the relationship between the concentration and the ultrasonic attenuation. Then the novel concentration measuring system was designed. The micro ultrasonic transducer array was introduced into the system, so the system can be sensitive as well as small. Finally, experiment was conducted to check the performance of this measuring system, and the results show that it could realize measurement quickly.

The paper introduces a method of fault diagnosis using fuzzy set theory. In the paper, the principle that a fault symptom either exists or doesnt exist is abandoned. A crisp number between 0 and 1 is used to denote the degree of fault symptom, by which the fault symptom vector is constructed. For every kind of fault symptom, a fuzzy pair-wise comparison matrix is constructed. The elements of the pair-wise comparison matrix are triangular fuzzy numbers which denote the qualitative comparisons between the membership values of the given fault symptom with the reference to a pair of possible faults respectively. The least logarithm squares method is applied to determine the membership of the fault symptom with respect to each fault, and then the fuzzy diagnosis matrix is constructed. A simple weighted addition is used to calculate the fault vector based on the fuzzy diagnosis matrix and the fault symptom vector. Center of area is used to determine the best non-fuzzy performance value of the fuzzy number, according to which the fuzzy numbers can be ranked. The ordering of all the possible faults based on the fault symptoms is determined. At the end of the paper, an example is used to demonstrate the procedure of fuzzy fault diagnosis.

For a vehicle with 5-speed AMT (Automated Manual Transmission), AMESim model of the powertrain is set up, and comparison of simulation and experimental values is carried out to test the reliability of the simulation model. Through the co-simulation of AMESim and Simulink, we use optimal control and PID control respectively to control the starting process. The simulation result indicates that the optimal control strategy can satisfy the requirement for the drivability and smoothness.

In this paper, we conduct a comparative experiment of the low-temperature single step mixing and multi-stage process mixing with low temperature single process mixing experiment platform. The experimental results show that the low-temperature single step mixing, compared with the traditional multi-stage process mixing, can save energy of about 13.3% and improve production efficiency of about 200%. The performance of final mixing has a significant increase in Mooney viscosity, the carbon black dispersion, and the physical and mechanical properties of the vulcanized rubber.

On the basis of reading a large number of literatures and collecting information, this article provides an experiment research on the single step mixing at low temperature. According to the principle of the single step mixing at low temperature, the feasible experiment platform is designed and several important technological parameters are selected; and the experiment is conducted adopting the orthogonal experiment, and the best technological parameters have been finally found out.

Experimental research on the relationship between rubber open mill mixing process parameters of roller pitch, roller speed and roller speed ratio changes and mix quality. The results show that the process parameters changes in open mill mixing process have significant effects on mixing quality and efficiency. And get the best process parameters optimization in open mill mixing process: the best changes trend of roller pitch, roller speed and roller speed ratio are from small to big, from small to big and from big to small.

Using the intelligent open mill mixing experimental platform, in the light of the all-steel radial tire tread formula, according to the experimental results and using regression analysis method and analysis software, we completed the establishment of the dispersion mathematical model about the open mill rubber. And through the inspection and verification of the model, we know that the multiple correlation coefficient of the model was 0.773 and the level of significance of the t-statistic and F-statistic are less than 0.01, also the absolute error between the predicted value of this model and the measured value is less than 0.7. It shows that the model is quite significant and can be applied.

Combined with the characteristics of power engineering projects, the paper introduces a kind of theoretical model that leads gray relational analysis and risk analysis into AHP appraisal method. This article describes the application steps of the model by a case. This article's main focus is the membership of risk index and the index weight. In the risk comprehensive evaluation model, the paper adopts the risk analysis method and gray relational analysis method to determine the membership and the weight of risk index. This model is considered to be the virtue of the subjective weight and the objective one. It can improve the accuracy of the evaluation.

The research of high-speed railway running economic benefit is important to timely know well the train operation state for the railway administration. A prediction model of high-speed railway running economic benefit is proposed in this article based on Gray model. The Gray model is a good example to make accurate prediction of the development of matters. According to the data analysis of Beijing and Shanghai railway stations, we can know that the result of prediction model is accurate, so the prediction based on Gray model is scientific and reasonable in the practical application.

Under the regional economic conditions, a passenger flow prediction model is proposed in the paper. It can predict high-speed railway passenger flow volume under the conditions of multi-mode, and guide the reasonable operation of high-speed railway effectively. According to the data analysis of Beijing and Tianjin railway stations, we can know that the reasonable ticket price plays an important role in high-speed railway operation benefit under regional economic conditions.

The study object is wheat. Through the observation and analysis on the morphological structure of wheat plant, the concepts of microstate, substrate and microstate are put forward, the wheat growth mechanism model is established, and thus the description and control of wheat morphogenesis process could be realized. Based on the branch structure characteristics of plant, the wheat morphological data model based on axis structure is proposed to realize the structural storage of plant topological structure and organ morphological feature data. On this basis, based on the thought of "growth model - morphological feature model - geometric modeling - display model", the technical framework of wheat form visualization is established and on the VC++ platform, the virtual wheat growth system is built with OpenGL. The running result of the system shows that wheat morphological feature can be well simulated with the system to realize the virtual display of the growth process in the individual growth period of wheat.

For a case of constant-rate liquid production from a single well centered in a horizontal, homogeneous-acting, isopachous, and infinite reservoir, based on fundamentals of fluid flow in porous media the bottom hole flowing pressure never stabilize. In the process of field well testing, however, pressure values measured by the pressure gauge which has a definite resolution value will not change after a period, so the bottom hole flowing pressure can be considered to be stabilized. According to this situation, through theoretical derivation, a stabilized time formula is firstly proposed, by which the time after which the bottom hole flowing pressure measured with a pressure gauge will be stabilized can be calculated, and the stabilized time for a given pressure gauge is in direct proportion to the liquid producing rate, but in inverse proportion to the resolution ratio of the pressure gauge. Applied the stabilized time formula, a new formula of detectable radius can be derived, by which the effect of resolution of the pressure gauge can be considered. Secondly, the time after which the value of the pressure gauge measured in the bottom hole of the observation well starts to change during interference testing is obtained, and the time is related to the fluid flow rate and the distance between the producing well and the observation well. The conclusion can be applied as a reference in the design process of working system during well testing.

In order to speed up the vehicles through the expressway toll station and reduce traffic congestion, we analysed of the No-waiting ETC(Electronic Toll Collection System) of expressway unifying the ETC theory and the RFID(Radio Frequency Identification Devices) technology. Firstly, we analysed system's hierarchy architecture, then detailed analysed the basic component of system, and designed the workflow and composing of functional modules, finally, established the model of ETC system of expressway based on RFID, it provides more practical guidance scheme for expressway ETC system.

A prediction model of train passenger flow volume is proposed in this article to help the railway administration's analysis of running strategies. The model is analysed based on industrial economic indexes and Cobb-Douglas theory to make the prediction. The model is illustrated by applying it to a numeral example, and the analysis of the error rate is made for further research.

To improve the manufacturing accuracy of NC machine tool, the thermal error model based on multivariate autoregressive method for a motorized high speed spindle is developed. The proposed model takes into account influences of the previous temperature rise and thermal deformation (input variables) on the thermal error (output variables). The linear trends of observed series are eliminated by the first difference. The order of multivariate autoregressive (MVAR) model is selected by using Akaike information criterion. The coefficients of the MVAR model are determined by the least square method. The established MVAR model is then used to forecast the thermal error and the experimental results have shown the validity and robustness of this model.

In order to achieve the digital management of null-pollution agricultural products certification and by adopting techniques such as Web Service, distributed database and workflow, this essay has completed the design and development of the system based on the J2EE platform. It includes certification data service subsystem, declare subsystem and certification workflow management subsystem. This system can highly automize and standardize the key link of origin and product certification such as the review of filing materials, site inspection and environment detection. It can automatically generate filing materials, inspection report and evaluation report. It has the function of sending documents among certification management departments at various levels and storing them respectively. This system has speed up the agricultural products origin and product certification integration process and realized standardized and digitalized management of certification work.

The electrochemical behavior of nucleobases has been studied in 0.1 M phosphate buffer solution (PBS), pH 7.4 without removing oxygen, using glassy carbon electrode (GCE). Cyclic voltammetry (CV), electrochemical impedance experiment (EIS) and square wave voltammetry (SWV) were employed in the measurements of the nucleobases electrochemical signals at GCEs. Guanine (G) and adenine (A) produced well-defined oxidation peaks at about +0.66 and +0.96 V under the CV sweep at 100 mV/s, respectively. SWV was particularly useful in investigating the electrochemical behaviour of pyrimidine bases. In the SWV detection, thymine (T) clearly appeared an oxidation peak at 1.1 V, while cytosine (C) and uracil (U) did a complex oxidation peak at 1.3 V. Nucleobases possess an irreversible and adsorption-controlled electrochemical process at GCEs in 0.1 M PBS (pH 7.4). The average surface concentrations (Γ) of G and A on the surface of the GCE were estimated to be about 1.6515×10−10and 8.8232×10−11mol/cm2, respectively. Due to the selective interactions of nucleobases with each other, the nucleobase oxidation peaks shift and new oxidation peaks appeared. The new oxidation peaks at +1.62 and 1.55 V may correspond to the oxidation of GC pairs and AT pairs, respectively. The detection of the electrochemical behaviour and selective binding of nucleobases in a physiological PBS at pH 7.4 is of particular interest for electrochemical sensor applications in physiological media.