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Current microcomputer protection experimental system is created based on LabVIEW. Each module was created based on the modular thinking (data acquisition module, start module, algorithm module). Functions of microcomputer protection were implemented. Fault data was generated by fault simulation software MATLAB. LabVIEW controls and loop structure achieved simulating a variety of action logical relationship of computer protection. This system had many advantages, such as visibility, controllability, authenticity and flexibility. The system was able to verify the performance of computer protection at different fault. The system was also able to analyze the situation of computer protection maloperation and misoperation, thus it further provided teaching platform for the three section current microcomputer protection experiment.

The satellite navigation signal system is so useful that it can provide autonomous geo-spatial positioning with global coverage. The satellite navigation signal simulation system possesses the traits of large scale, complex structure and various model types, and the real-time performance of the simulation system is exigent. The simulation real-time performance index will be analyzed and tested roundly. Firstly, the framework of the satellite navigation signal simulation system is introduced. Secondly, several index such as simulation step-time, time function and network data transfers, which can affect the real-time performance of the simulation system, are analyzed. Finally, four real-time performance indexes such as frame overflow, the definition of frame synchronization and time synchronization, the precision of time synchronization etc, are tested and validated in detail. By analysis and test, the result shows that this simulation system possessing higher real-time performance and it can meet the real-time simulation requirement of the simulation system. This simulation system can also be used to validate the real satellite navigation signal system.

The vertical distribution of aerosol extinction coefficients, and relativity between aerosol and BC the within summer planetary boundary layer (PBL) over the observation site are shown in this paper. The data indicates that the aerosol is almost trapped within PBL and troposphere layer is rather stable and the main composition of aerosol in Beijing is BC. The multi-layer structure of the aerosol distribution is obvious.

Object:To explore the feasibility and effects of external drainage from intestinal cavity in the surgical treatment for the neonates with necrotizing enterocolitis. Methods: A retrospective analysis was conduct on 22 cases of newborns with extensive and multiple intestinal necrosis found intraoperatively, all of which could not accept first-stage resected, treated by traditional operation or by external drainage from intestinal cavity between January, 2008 to January 2013. Duration of operation, amount of bleeding, and the survival rate after operation were compared between the two groups, which were divided by surgical methods. Results: No significant difference was observed in age, amount of bleeding and body weight (P>0.05) between the two groups. However, duration of operation and the survival rate after operation were significantly shorter in the patients by external drainage from intestinal cavity than the patients by traditional operation (P

In actual operation, the rising load will lead to the reduction of pressure because of the long delay of the boiler. It can lead to the main steam pressure lockout in severe cases. The proposed model is derived by the principle analysis of control object and the introduction of load feedforward. The unidirectional decoupling method is verified by the simulation in Matlab. Not only the decoupling has achieved good results, but also the performance of the control system has been greatly improved. All the above study are based on a 1000MW power unit.

Object: To investigate effects of the high ligation of hernia sac with absorbable string for children with indirect inguinal hernia. Method: A retrospective analysis of 92 patients with inguinal hernia who underwent the high ligation of hernia sac was conducted in the present study, in which 20 cases underwent the high ligation of hernia sac with absorbable string while 72 cases treated with the high ligation of hernia sac with non-absorbable suture. The mean operation time, mean intraoperative blood loss and average postoperative hospital stay and postoperative pain rating were analyzed. Results: Though no statistical difference existed in the mean operation time, mean intraoperative blood loss, average postoperative hospital stay between the two groups (P>0.05). However, the postoperative pain in the high ligation of hernia sac with absorbable string group was significantly lower than that of the non-absorbable group. Conclusion: Compared with that of the high ligation of hernia sac with non-absorbable string, there is lower grade postoperative pain in the high ligation with absorbable suture.

Object: To explore the feasibility of laparoscopic repair of congenital diaphragmatic hernia in neonates. Methods: A retrospective analysis was conduct on 14 cases of newborns with congenital diaphragmatic hernia treated by laparoscopic diaphragmatic repair or laparotomy between September 1, 2011 to December 31, 2013. Duration of operation, amount of bleeding, and length of stay were compared between the two groups, which were divided by surgical methods. Results: No significant difference was observed in duration of operation and amount of bleeding(P>0.05) between the two groups. However, length of stay was significantly shorter in the patients by laparoscopic diaphragmatic repair than the patients by laparotomy (P

Take advantage of cloud computing and the internet of things, combined with the fault diagnosis expert system and knowledge sharing on automobile construction vehicle condition monitoring and fault diagnosis platform, The real-time monitoring of vehicle state in person–cars, cars–cars, enterprises–cars, reliable estimation of vehicle safety problems to improve vehicle driving safety.

With the popularity and development of application of network in colleges and universities, students enjoy the convenience of learning and school life network at the same time, it could also be that excessive and irregular use and create network obsession or addiction led directly to an increase in psychological problems among college students, lack of ideals and beliefs, moral quality of landslide, thus affecting the students ' healthy and smooth growth. How to educating and guiding college students, the prevention and resolution of network with negative consequences for physical and mental development of college students, into a new era, the new situation of ideological and political education of college students under the subject of intense interest.

This article taking into account the network efficiency, QoS, resource consumption, latency, performance and ease of use, and implementation of the system on the basis of factors such as the complexity, media management, node in the system management, and streaming media QoS control, buffer management, incentives, and other key algorithm and protocol analysis and design, and trying to achieve a balance between the factors. Finally developed real-time streaming data distribution system based on P2P MStreaming program, its resources quickly and easily launch and positioning, exert the advantage of P2P technology can effectively solve the problem of server bottleneck link, decentralized services and resource consumption.

Many research papers implemented fault diagnosis and prognosis when there are many history data. However, for some capital and high reliability equipment, it is very difficult to acquire some run-to-failure data. In this case, the fault diagnosis and prognosis become very hard. In order to address this issue, continuous hidden Markov model (CHMM) is used to track the degradation process in this paper. With the degradation, the log-likelihood which is the output of CHMM will decrease gradually. Therefore, this indicator can be used to evaluate the health condition of monitored equipment. Finally, bearing run-to-failure data sets are used to validate the model’s effectiveness

During the process of the Smart Grid systems construction, the Safe Access Platform has an increasing important role. Not only could it meet the demand that people of power system can telecommute, but also provides different level of security mechanisms for various smart devices, such as Hand-hold Terminal System PDA, Ultra Mobile Personal Computer (UMPC) and Wireless Data Acquisition Terminal. Determining how to guarantee the internal security and meet the security requirements of access control based on roles is an important subject. The paper presents a new network access control system (NAC system) based on roles. According to the security metrics of the network access equipment (NAE), the NAC system has been designed and implemented to provide different safety strategies for different application scenarios. Besides, 802.1x and L2-IP are discussed specially as the most important key techniques of the implementation of the system.

This paper studies on the effects of the heat treatment on cement. The results show that mixing the FGD gypsum which has been processed the heat treatment into the cement do has a certain influence on the cement, the strength of the cement is increased but the setting time is normal, and the rates of water loss and shrinkage of the hardened cement paste is significantly reduced, thus shrinkage cracks are effectively prevented.

Considering the importance of PM (preventive maintenance) in reliability engineering, the formula is given to calculate spare demand rate for the policies of age replacement policy, minimal maintenance policy and block replacement policy. And average spare demand rate was analyzed for age replacement policy, and an approximate empirical formula with PM interval and parameters of Weibull distribution was given compared to CM(corrective maintenance) and PM. Otherwise, compared to minimal maintenance policy and block replacement policy, the demand rate was analyzed in order to better forecast the spare parts demand.

To clarify the utilization of flue gas desulphurization (FGD) gypsum as the retarder of cementbased materials,the effect of the properties of the slag cement with different tempemtuIe treatment of FGD gypsum was studied. The results reveal that in the case of adding the same amount, the setting time of cement shortened with the increasing of heat treatment temperature of FGD gypsum. The influence of different heat treatment processes on the strength of cements was not obvious and the strength development was good. The water consumption of normal consistency for cements changed slightly. Stability was qualified.

Web mining algorithms are widely used in e-commerce. Tourism e-commerce develops fast in recent years in China but the application of web mining algorithms stays in low level compared with some developed countries. This paper first discusses two major web mining algorithms: the Association Rules algorithm and Clustering Analysis, and then analyzes the application of web mining algorithm in tourism e-commerce. It concludes that web mining algorithms can help tourism e-commerce to improve web design, increase online sales and provide better personalized services for web users.

In order to improve the accuracy of the pump flow control system,With the application of hydromechanics:the actual flow of the pump is restricted by head,the mathematical model of the fluid flow control system is established.Through the analysis, which obtained three kinds of unit step response curve of the pump flow control when it is under the condition that without using the PID,using the PID and using the BP neural network combined with the PID control. It is concluded that the efficiency of using the BP neural network combined with the PID is much better, Which can improve the pump flow control system's accuracy.

This paper carries research on the method of smooth method of Brushless DC Motor. Brushless DC motor applied in human skeleton booster is required to switch frequently among four-quadrant operation states of forward rotation, backward rotation, electro motion and braking control. Basically, this switch is expected to be soft. That means it is unexpected that motor comes about the phenomenon of impact of great force, speed mutation and so on. According to the requirement, the paper presents the design of driving circuit of brushless DC motor and put forward a corresponding control method. In the end, the paper proved the correct of this method by using simulation and experimental data.

Linearlinking polystyrene nanospheres (LPSs) with uniform size dispersion were synthesized by the emulsifier-free emulsion polymerization method. And with the adding of divinylbenzene (DVB) crosslinking polystyrene nanospheres (CPSs) was also prepared. It was found out that the partical size of prepared nanospheres changed with the continuous increment of added DVB. The sulfonation of resultant polystyrene nanospheres yielded solids with sulfonic acid groups. The relationship between nanospheres material structure and attached acid groups was investigated in detail. It was observed that the amount of added DVB is the main factor which can affect the amount and thermal stability of attached sulfonic acid groups. The catalytic performance of resultant solid acid catalysts was evaluated through the esterification reaction of methanol with acetic acid. Moreover, the prepared sulfonated polystyrene nanospheres show higher acetic acid conversion than the commercial one, therefore the sulfonated nanospheres could be an excellent potential replacement for liquid acid catalyst.

A low-power consumption heat meter with long-distance communication was designed based on MSP430F413 and TDC-GP2. The new flow measurement circuit and correction method were introduced in detail, which improved the accuracy of the heat meter effectively. In order to reduce the power consumption, the running time of the CPU was minimized, the floating-point operation was avoided, and the communication circuit was designed specially. The experiments showed the design is valid.

The transmutation target of nuclear waste material has been fabrication by a powder metallurgy method by using Alumina as the matrix and CNTs as reinforcement. The effect of different nanotube contents on the fracture toughness and the bending strength was investigation. The results showed the fracture toughness and the bending strength of composites increased with increasing CNTs mass fraction when the content of CNTs was less than 1.5%. However, when the contents of CNTs greater than 1.5%, the fracture toughness and the bending strength of composites decreased as the content of CNTs increased. Possible mechanisms are discussed in detail in the paper.

This paper introduces several methods of soft start of belt conveyor, Through the analysis of all kinds of soft start mode, the prospects of development of soft start device of belt conveyor, and through the comparison of several commonly used start speed curve, the reasonable start speed curve, pointed out the direction for the research of soft start device of belt conveyor.

In view of the difficulty in the selection of technological parameter in power-mixed pulse electrochemical polishing, a scheme based on neural network for the selection of technological parameter was put forward. The model of Surface toughness Forecasting was established. After being compared with experiment data, it was found that the experiment results and expected results share much similarity. It indicates that the system is able to predict the roughness of surface accurately under a given condition. Therefore, it can cast some light to practical power-mixed pulse lectrochemical polishing.