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The distribution of substrate temperature plays a decisive role on the uniformity of polycrystalline diamond films on cemented carbide tools with a long flute, prepared by a hot filament chemical vapor deposition (HFCVD). In this work, the heat dissipation mode at the bottom of tools is a focal point, and the finite volume method (FVM) is conducted to simulate and predict the temperature field of tools, with the various materials of the holder placed under the tools. The simulation results show that the thermal conductivity of the holder affects the temperature difference of the individual tools greatly, but only affects the temperature of different tools at the same XY plane slightly. Moreover, the ceramic holder can reduce the difference in temperature of an individual tool by 54%, compared to a copper one. Afterwards, the experiments of the deposition of diamond films is performed using the preferred ceramic holder. The diamond coatings on the different positions present a highly uniform distribution on their grain size, thickness, and quality.

Coal Mine Safety Monitoring System is an important material guarantee for Coal Mine Safety Production. At present,most China's coal mines have established safety monitoring system, but in the use of safety monitoring system we've found many problems. In order to solve these problems ,our paper put forward some practical solutions. [1].

Coal mine electromechanical equipment plays an important role in the process of producing coal.For the lack of scientific management philosophy and effective management methods, China’s Coal mine electromechanical equipment is now facing severer and severer challenges in its way of moving ahead-shortage of investment, hysteresis of management-hazards emerge in every single seconds in the production of coal mine. These hazards,however,does not merely affect the normal production, but will also increase the risks of accidents.Therefore,in order to improve the management level of electromechanical equipment and optimize the utilization of mechanical and electrical equipment, coal mine managers should pay their attentions to the following three aspects:the importance of coal mining equipment ,the importance of training mechanical and electrical personnels and the importance of accelerating the construction of mechanical and electrical information management system [1].

Tunnel roof separation monitoring is an important research content of tunnel supporting technology, it is of great significance to guarantee the safety of mine production. The traditional detection methods of roof separation have disadvantages of low precision, poor reliability, high cost, and the comprehensive analysis of measurement results is difficult. In the paper, a roof separation monitoring device based on STC12C5A is proposed. It has the core of STC12C5A single-chip microcomputer, and realizes the accurate measurement of displacement by using the fine drag-rope displacement sensor, and realizes the data communication and sharing by using bus interface. The device can achieve real-time, reliable monitoring of roof separation condition and also can make pre-caution to the possible production accident.

In order to solve the lubrication problem of the hydrostatic center rest, a optimal design concerning structure of hydrostatic center rest is studied. ANSYS has been used to compute three-dimensional stress and deformation fields of hydrostatic center rest. This research analyzes the stress and deformation of hydrostatic center rest, and it has revealed its stress and deformation distribution law. Results indicate that a characteristic will be improved by optimal design and the reliability of a hydrostatic center rest can be predicted through this method.

As the application of the information network technology continuously extended, library management service platform is experiencing a shift to the information service system. In the library information management field, researchers are seeking a library identification system which is more convenient and comprehensive. Under the circumstance of the information technology conditions, Radio Frequency Identification (RFID) technology completes the automatic identification of the electronic identification tags--the two-dimensional code. The RFID technology is a contactless scanning recognition technology. And the core technology of RFID can be described as follows: using two-dimensional code as the filter identification tool according to backup data of the book management.

The dynamic performance of modern machine tools is more and more highly emphasized. The research purpose of this paper is to research dynamic performance of gantry machining center through modal experiment. In this paper, the theory of relative excitation test on the machine tool is expounded, and relative excitation test is carried on gantry machining center and then the modal parameters of this machine tool are obtained through experimental modal analysis. Analyze the weak link of this gantry machining center, show that the stiffness of Z direction of Z to feed component of this machine tool is insufficient and the stiffness of X, Y direction of ram is insufficient.

Based on the disadvantages and problems of current detect ways, come up the testing system which using numerical controlled oscillator (NOC), Digital Radio Frequency Memory (DRFM) and digital down-covert to intermediate frequency (IF) processing, introduce the background information, main functions, total structure and design implementation.

The Cu-based SS-O solar spectrum flat-plate selective absorption coating system was prepared by the method of direct current reactive sputtering coating films, in which, two layers are SS-O absorbing layer and one is Si-O anti-reflection layer. The reflectance spectra of the absorption coating system was measured by UV3600 spectrophotometer, the reflectance and absorptance of the absorption layer and the anti-reflection layer were calculated, and certain experimental tests were conducted on the prepared absorption coating system in terms of the salt spray resistance performances, thermal stability and damp heat stability. The results show that the SS-O selective absorption coating which was prepared by magnetron sputtering technique possesses excellent processing property, corrosion resistance and thermal stability, whose absorption rate and the emission ratio have reached the level of the German blue tape series. It can meet the domestic demand for high-level flat-plate market.

The gas sealing performance of electronic sphygmomanometer is an important index of its quality control. At present, the gas leak detection of sphygmomanometer is mainly by manual, which has disadvantages of low efficiency and precision, huge impact of human factors and so on. An automatic and high precision gas sealing performance inspection module is proposed in the paper, which solves the problems of pressure calibration and gas leak detection of sphygmomanometer products. The paper also introduces the principle and implementation of system project. The module is designed by STC12C5A single-chip, KPM DC air pump and the pressure sensor of E8CC, which has advantages of high precision, high efficiency, low cost, and flexible operation etc.

This work describes a simulation research concerning dynamic effect of multi-pad hydrostatic thrust bearing having rectangular recess, sector recess, ellipse recess and I-shaped recess in order to solve the loading capacity of the hydrostatic thrust bearing. Three-dimensional pressure field of gap fluid between the rotation worktable and the base has been computed by using the Finite Volume Method. This study theoretically analyzes the influence of recess shape on dynamic effect of the bearing according to computational fluid dynamics and lubricating theory, and the simulation results indicate that an improved characteristic will be affected by recess shape easily. Through this method, the safety of a multi-pad hydrostatic thrust bearing having different cavities can be forecasted, and the optimal loading capacity of such products can be achieved, so it can provide reasonable data for design, lubrication, experience and thermal deformation computation for hydrostatic thrust bearing.

Signal source with high precision and programmable is needed in modern scientific research, communication system, teaching apparatus, electronic measurement and so on. In the paper, a portable signal generator is proposed, which has a core of AT89C51 and programmable DDS integrated chip AD9833. The paper also introduces the principle and implementation of system project. The generator can output sinusoidal wave, square wave, triangle wave, dc voltage, and it has manual and SPC two working mode, can implement PC SPC output through RS232 communication interface. Experiments show that the system has advantages of high precision, wide scope, small size and flexible operation etc.

Linear rolling guide has gained wide application in various CNC machines. As a main joint of the machine tools, it makes great impact on the dynamic characteristics of machine tools. It is therefore necessary to study the dynamic behavior of linear rolling guide. And external load is a factor that affects the dynamic characteristics of linear rolling guide. In this paper experimental approach was used with the aim of studying effects of external load on dynamic behavior of linear rolling guide. The experiment contained some modal tests of linear rolling guide ways when they were loaded forces of different sizes.

Vehicle safety is one of the most important design elements for all types of vehicles designed for use on public streets or roadways. Compared with traditional vehicles, besides other safety issues to be considered, a new issue that is the high voltage management problem should be taken in consideration very carefully in the electric vehicle development. This paper analyses the high voltage system in the electric vehicle and proposed a high voltage management system which implements several functions like power-up and power-down control of the high voltage system, high-voltage-circuit interlock protection, protection of electric leakage of the HV system etc. Because of the high voltage management, the electrical safety goals could be achieved and the protection of human being from high voltage hazardous becomes possible.

The necessity of the Li-ion battery balancing is elaborated by this paper. It also introduces the classification of the balancing method existed and compares the advantages and disadvantages of various balancing circuit. By comparison, we focus on researching on the inductor-based active balancing of Li-ion battery, and prospect the direction of the balancing circuit.

The objective of the study is to improve the impact resistant performance of a special vehicle’s front sliding plate. For this, a performance evaluation indicator called critical failure velocity is proposed in this paper. By regarding the impact velocity as the variable, this paper carried out a numerical simulation of the changeable stress and deformation due to the impact on the different front sliding plates which are made by aluminium alloy, high strength steel and special engineering plastics by ABAQUS／Expticit. In this way, the relationship between various impact velocities and maximum Mises stress on the front sliding plate can be got, and the critical failure velocities can be found through the relationship. Then, as a comparative analysis of various materials’ critical failure velocities has been made in this paper, the front sliding plate’s impact resistant design

With the development of the electric vehicles, serial connected cells have a broad prospect in the future. But the difference of the serial connected cells especially for Li-ion cells is prone to cause a lot of problems, such as overcharge and overdischarge. For these reasons, various cells balancing methods are applied. In this article main balancing methods will be compared, and as a result, the inductive charge transfer method will be adopted to balance the cells due to its obvious advantages. Furthermore, the principle and the realization of this balancing system will also be explained.

Based on the comparison with the other one of the current mostly used battery monitoring plan and analysis, this paper decides to adopt the architecture of the single battery monitoring module with CAN gateway, paper describes the design of the single battery detection module in every detail, including the description of module architecture, the hardware design and the software design, and this module has been done the off-line test verification, results can meet the requirements of stabilization and reliability.

Vehicle safety is a very important design element for all types of vehicles designed for use on public streets or roadways. Traditional vehicles produced with liquid fuels have a long history of creating appropriate safety countermeasures. With the onset of new electric propulsion and charging systems, proposed for large scale production, new safety design elements will need to be provided to vehicle developers. This paper attempts to summary the usually protective measures against electric shock on electric vehicles and to analyze these measures to formalize a series of important safety references for vehicle developers.

Battery Management System (BMS) mainly focused on the estimation of State-of-Charge (SOC) previously. However, the single SOC could not reflect the true state of battery. Life prediction and performance state estimation becomes an increasingly important issue in each battery life stage. A practical and accurate battery life model is their basis. Much research work has been done in recent years to improve the accuracy and application range of battery life model. This paper introduces commonly used battery life modeling methods and summarized the characteristics of each model and their common applications, and the emphasis for future study is proposed as well.

Electric vehicles have the ability to drastically reduce petroleum use. As the battery used in EVs appears to be the main technical barriers both from a performance and cost perspective, the main efforts have been focused on how to select appropriate power train system for the better dynamic performance. This paper introduces some methods of parameters design of EV’s main power train components, such as the lithium-ion battery and AC induction motor. Then we build a battery model, a motor model and vehicle simulation models using ADVISOR software. Meanwhile, this paper proposes simulation results of the entire vehicle’s dynamic performance, which shows that the power train components’ parameters designed here basically meet the vehicle’s requirements.

This article introduces a Hardware-In-Loop test platform for electric vehicle Cell Battery Management System (BMS). At first, system structure of test method is projected to make requests for a battery emulator which is the main work of test platform. Then hardware is designed to simulate the input and output signals of BMS. The model for Lithium-ion battery, hardware driver and relative algorithm are built in Matlab/Simulink. After the model is validated, automatic code generation is performed. The code is downloaded to hardware platform. This platform enables validation of BMS instead of using real batteries.