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Low impact toughness is the major obstacle to impede the applications of brittle ceramics such that a very small crack may induce catastrophic fracture of the bulk components. Thus, enhancing the impact toughness of ceramics is virtually important. It is generally accepted that weakening the interlayer binding strength of the laminated material is beneficial to the fracture toughness of the laminated ceramics. In this paper, alumina / silica layered composite ceramics were prepared by impregnating the alumina interlayers with silica sol, wherein the interlayer bonding strength was controlled by adjusting the sintering temperatures from 1000°C to 1600°C. Lowing sintering temperature warrants the weak interlayer bonding strength, which results in the occurrence of the multiple bending strength-strain curves and improve the material's fracture strain and impact toughness. Crack deflection along the weak interface layer is the main mechanism for the enhanced toughness and crack tolerance. When the sintering temperature decreases from 1600°C to 1200°C, impact toughness increases from 4.42 kJ/m2 to 6.95 kJ/m2, and fracture strain measured by three-point bending increases from 0.25% to 0.36%. Finite element software was used to simulate the differences in stress distribution.

Numerical control (NC) programming is the critical part for the NC manufacturing system. The NC manufacturing programming is the concentrated reflection of design of component-processing, which reflect directly the productive efficiency of NC manufacturing and the quality of products. This paper suggests that the Multi-agent as the theoretical basis and development platform to research the NC programming based on agent, in order to reach the autonomy of programming unit, the NC programming unit based agent as its the processing object, and self-organization of system. The NC programming based on Multi-agent can achieve the autonomy and functional maturation of each programming sub-unit, and can also achieve the coordination and cooperation among all the dependent units, therefore, the system processes the self-organization ability. One standard process template is created relay on this technology, in order to templatize and intelligentize the process flow and process data of NC manufacturing.

Power quality disturbance detection and identification is the prerequisite and basis for the power quality management and control. This paper presents a new power quality disturbance detection and classification method. Firstly, the time-time transform is applied to power quality disturbance signal analysis. According to spectrum analysis results of the diagonal elements of time-time transform matrix, a preliminary judge about whether the disturbance signal contains harmonics and inter harmonic was given. For disturbances with non-harmonics, based on time-time transform modulus matrix diagonal sequence, the beginning and ending time of the disturbance is located, and the disturbance amplitude is calculated. For the disturbances which contain harmonics, time-time transform is perform twice to get the row mean value curve and the column mean value curve, which are required by disturbance time location and amplitude measurement. Finally, disturbance classification had realized by using rule tree. Simulation results reveal that this method is very robust and adaptable, which can identify transient power quality disturbance with minor magnitude under noisy environment, and the recognition rate is satisfactory.

After the primary exploration of the preparation procedure of phenolic foam, we studied the modification of phenolic foam by graphene oxide. According to our researches we found that the influence of modifier to the percentage of close area was very little, but it can greatly decrease the thermal conductivity of phenolic foam. In this way, phenolic foam thermal conductivity can be reduced to 0.025 W/m.K.

Neutral un-effectual grounded system (NUGS) is widely used in Chinese medium voltage power distribution network. However, existing earthed fault location methods in NUGS are not satisfactory in practical application due to weak fault current and unstable arc. Based on analysis of spectrum characteristics of current signals in single-phase earthed fault feeder, this paper proposed an earthed fault location method based on support vector machine (SVM). Firstly, the zero sequence current signal was sampled, and its spectrum was gotten by discrete Fourier transform. Secondly, the three dimensional feature vector that constituted by fundament, harmonic, inter harmonic component, had been extracted as the input of SVM. Furthermore, the SVM was trained with the samples obtained by simulation under different fault distance, different fault resistance and different fault close angle. Finally, the earthed fault feeder is selected using the trained SVM. The simulation results indicate that the fault location by the presented method is more precise.

On the condition of protecting the critical load, it is necessary to restore the service of outage area without fault as soon as possible after the occurrence of fault in smart distribution system. A fast service restoration method is proposed for medium-voltage distribution system with distributed generations, which combines intentional islanding of DGs for network reconfiguration. Under the condition of safety limits, the out of service areas are achieved maximization of restoration, making full use of DGs. The whole process of restoration is regarded as a multi-stages decision problem, and divided into four stages. Compared to the existing algorithms, this method can effectively avoid the time-consuming and search results problems, and the simulation results are better. The effectiveness and practicality of the propose approach is demonstrated by simulations on a PG&E 69-nodes system with DGs.

With the rapid expansion of the grid, how to solve the security and stability of power system has become a hot problem. As a power system after a serious accident the necessary security measures, black-start programs are expected to play an extremely important role in reducing the loss of equipment and user outage and decreasing the outage time. The present paper proposes a series of advantages about distributed generator (DG) and raises evaluation indexes of DG in black-start. The fuzzy hierarchical model is built based on the general steps of fuzzy decision theory. According to the concept of triangular fuzzy number, considering the indexes of which the weight value is judged by means of trapezoidal fuzzy number complementary judgment matrix. Finally, by actually case anglicizing, the paper demonstrates the scientific nature, effective and easy to operate of the method. And a new decision-making method for the optimal DG start-up sequences based on fuzzy AHP is proposed.

The p-aminobenzensulfonate-phenol-formaldehyde (APF) condensate is synthesized and characterized by FTIR and TGA analyses. Its properties as drilling mud fluid loss reducer are studied with respect to fluid loss and particle size distribution. In addition, the effect of salt on properties of APF condensate was discussed. Test results show that the APF condensate not only possesses higher thermal stability than sulfomethylated phenolic resin (SMP), a commercial drilling mud additive, but also achieves good property of fluid loss control by reducing the permeability of filter cake; the fluid-loss controlling properties of APF condensate dropped with the increase of concentrations of NaCl.

The existing logistics management systems can not meet the needs of business change and reorganization. In view of this situation, put forward a logistics management system based on workflow. This system used logistics enterprises busyness process as the core, and organizes the logistics business by the workflow, improve the logistics management level and work efficiency. The system has characters of flexibility, scalability.

Proposed a extend design pattern, which oriented distributed environment. Design framework in which import some components, such as command bus, command executor. Design the structure class diagram of the pattern. Expatiated components’ specific function, and analyses the command execution process in the pattern. Based on the pattern, when developers design command classes, there is no need to consider how to sequence the command object and send it to server, and they don’t worry about receiving data from server and anti-serialize from the received data. Conclude that developers can use command pattern in a network transparent manner in accordance with the original way.

This paper introduced an optimization model to address dynamic speed control strategies for achieving network-wide speed harmonization. Genetic Algorithm (GA) was applied to search the optimal solution of the proposed model. During the search process, a computational fluid dynamics (CFD) based analytical model and microscopic traffic simulation VISSIM were applied to evaluate the performance of possible solutions. The proposed model can be used to determine the deployment of dynamic speed limits, the displayed speed limit, and the timing to change these speed limits. The proposed model was tested using VISSIM in an urban freeway network of about 12 miles long. Different simulation scenarios with varying AADT from 60,000 to 12,000 were tested. It was found that when properly implemented, dynamic speed control can improve traffic flow conditions, reduce congestion and emission, and enhance network throughput. For example, in the selected urban freeway network with the AADT of 80,000, the proposed dynamic speed control strategy can save 5% average travel time, reduce 9% of the vehicles with high collision risk and about 11% emission.

Analysis of the intelligent traffic service platform system structure and key technology of cloud computing, proposed mass sensing information processing scheme based on the intelligent traffic service platform. First the scheme proposed system architecture, designed a multiple functional unit modules of the system, through the combination of these functional unit can realize the configured service for tens of thousands of service and tenants. Then, the system adopts Hadoop open source framework for distributed computing. Finally, the system is realized in the intelligent transportation service.

nanosilica porous thermal insulating composites belong to super thermal insulations, which are prepared by dry molding technology. They have many advantages in comparison with aerogel such as easy preparation and good mechanical property. However, springback phenomenon is found in the process of molding. The springback is easy to lead to cracking of the samples, which directly affects applications of the composites. In order to solve this problem, steam curing method is introduced and the effects of steam curing medium and steam curing time on springback ratio are investigated. The results show that the springback ratio of composites is only 6.45% when water is selected as steam curing medium and the optimum steam curing time is 30 min.

In order to intrusion detection system functional analysis easily and adapted to changing requirement, object oriented modeling technology is applied in Packet Capture System. The system architecture is proposed first, functional analysis is given for it s components. Static model and dynamic model are separately founded by united modeling language. An analysis of the advantages of the system is placed in the end.

In order to improve the vehicle alone path finding way, put forward a kind of road navigation algorithm based on agent. First put forward the intelligent design method, and then the intelligent design is mapped to different kinds of the intelligent agents. And then expounds the function of operation control agent, agent, Lane agent and intersection agent needs to realize. Finally, based on these agents of the navigation algorithm is designed using Dijkstra algorithm.

As the world's biggest energy consumer and the world's first car production and marketing country, car exhaust emissions have become an important cause of serious environmental pollution. The paper calculates the life cycle costs of HEB, BEB, and CDB by the life cycle cost model considering the environmental benefits in the case of small public transportation system being the big scenarios. The paper takes the capital airport shuttle bus system as an example, analyzing applications of alternative energy in the system, thus providing evidence for applications of alternative energy in a small public transportation system, improving continuously the proportion of electric energy in the consumption of end-use energy, promoting social energy conservation and mitigating environmental pollution problems.

According to the requirements and characteristics of mobile Internet content security audit, designed and implemented the mobile Internet content security audit system. The system captured and processed data through a data acquisition proxy server for mobile user network access, and then set keywords by matching rules, finally carried out the content audit through the single mode and multi pattern matching algorithm.

In order to narrow the range of suspects and clear direction of investigation quickly, a smart stride characteristics test system was designed and development. The system design concept and concrete implementation of the key technologies such as image mosaic, PCA-based stride characteristics extraction and membership test were all introduced in detail. Actual stride characteristics test experiments show the effectiveness of the system.

Today, faced with the problem of international energy supply difficulties, due to the nuclear power’s fewer of its resources consumption, little environmental pollution and other advantages, it has become one of the essential pillars of the electricity supply. This paper analyzed from a comprehensive localization of nuclear power plants, then use the non-equidistant GM (1,1) model and the exponential regression model to predict the construction cost of nuclear power, and do the error analysis. The conclusion that by increasing the degree of localization of domestic nuclear power construction, which can effectively reduce the cost of building nuclear power plants conclusions.

The diagonal cracks in the web of box girder bridge which caused by excessive loss of vertical prestressed tensioning force are particularly common. In order to effectively detect the real force of the vertical prestressed rebars. Take the exposed section of the vertical prestressed rebar as an analysis entity, and take the rebar as a rigid body; the anchoring segment is simulated by an annular outrigger and an annular elastic support. When vertical pretress tension changes, the stiffness of elastic support and the vibration frequency also change accordingly, the change of the value of tensile force can be reflected by the vibration frequency. Combined with the model test data, the nonlinear elastic parameter model between the finish .deformed rebar vertical tensioning force T and the space elastic support stiffness K is established. The validity of the method was checked by extension test. The study indicate that this method is accurate, fast and convenient for engineering applications, can effectively improve the construction quality.

The adaptive fuzzy logic systems are constructed in this paper by utilizing the data information sampled from the inputs and outputs of unknown functions in the nonlinear systems controlled, and then output stable controller is synthesized for a class of uncertain nonlinear systems based on the universal approximation property of adaptive fuzzy logic systems. Finally, the simulation shows the validity of the method in this paper.

The results of the same modal analysis exhibit obvious diversity due to the different options of the finite element types and the modeling methods. Modal analysis was carried out on EMU aluminum alloy welded profile using finite element analysis, then mode shape and natural frequency of each model was abstracted, and then the results of simulation and experimental were contrastively analyzed. Based on these, a fast and reliable modeling method and a reasonable element type were obtained, which would be able to eliminate the blindness of the choice of modeling methods and element type, thus achieving a more reasonable theoretical analysis results that provide the reference for structure design and verification and the basis for improving the efficiency and precision of simulation analysis.

This paper studies the design and use of spare parts and system management module, and designed a development model based on B/S architecture. System using MVC framework, using AJAX pages, data and business separation and a series of advanced technologies developed for the management of spare parts. System design mainly uses high-performance UNIX system database server and a set of easy to maintain Windows Server2003 system as an application server, middleware using open source Tomcat, database using the Oracle database, ensure the system's high availability and high cost. The function module is based on B/S model include: procurement module, inventory management module, allocation management module, quota management module statistics query module and module-based information management and system maintenance module, the system message announcement. Spare parts management system and the advantages are analyzed to prove that the system is capable of successful application.

Analyzed of GPSR routing algorithms in networks, and applied it to path selection algorithm of traffic guidance system. Then improved it combined with the road congestion information, introduce congestion distance factor, saving travel time.

Clouding computing and virtualization technology have brought immense effects to software organizations including software testing region. At the same time the method and related technology will be changed a lot. Some concepts, structures and characters are described in this paper. Software testing should be regarded as a service. Four typical patterns of cloud testing and the relations among them are showed in the paper. Combined with the virtualization technology, the frame of TaaS (Testing as a Service) is defined too. In the meantime, cloud testing and traditional software testing is compared with each other. At last, the main research contents about software testing in virtualization environment are summarized.

Using self-designed 30cm×30cm gas explosion experiment pipe and data acquisition system, we found Fe-Ni foam metal suppresses better gas explosion. We analyzed mechanism of suppressing gas explosion from material characteristics,. The three-dimensional holing-through structure of foam metal can quench exploding flame and decline exploding shock wave. Foam metal material has dual advantages of material and structure which can suppress transmission of fire and shock wave. Effect on different parameters of Fe-Ni foam metal materials was contrasted from declining overpressure and flame temperature, and suitable Fe-Ni form metal was optimized for engineering application.

For marine water pollution problems, According to the phenomenon that the refractive index of the seawater will change after been polluted .we designed a new fiber optical sensor, and completed a marine pollution monitoring automatic warning system with the sensor. One S (single mode)-M (multimode)-S-M-S structural optical fiber sensor based on the theory of M-Z Interference was made. Due to de refractive index of the fiber cladding will be affected by the environmental solution. We can determine the relationship between the movement of interference spectrum and the refractive index of the solution. With a center wavelength of 1553nm fiber Bragg grating and a coupler to obtain the change of the intensity of the light, then though the specific circuit, we can change the light intensity into the voltage values. Then enter the computer through the acquisition card, real-time reporting of environmental refractive index size, and according to the software set threshold alarms. The refractive index in the range of 1.330-1.390, the system of measurement error is less than 1%.

This thesis analyses the problems that exist in the fields of fiber-sensor experiment, and real-time draw the diagram of creating a flat about optics-intervene, using computer and camera to replace the traditional observation which are with the eyes to calculate the number of the moving stripes, and using the combination of temperature sensor and computer to replace the traditional thermometer. At the same time, the computer can collect the temperature and the number of moving stripes, and real-time draw the diagram of the temperature and the number of stripes, or draw the relationship of the tension and the number of moving stripes. Experimental results show that the system is stable and reliable, as well as having an age-feeling much more.

Aiming at the growing red tide, we designed a simply red tide predication device which is intended to measure the content of red tide alga in seawater. We make use of Chlorophyll A’s spectrum characteristic, which is in the red tide alga. Then combined with narrow spectrum of LED, high photon-electron efficiency and high response rate of PIN diode, different idea, we designed a circuit to amplify, acquire, process the optoelectronic signal and put the warning information on PC. We can know the accurate content of red tide alga in seawater in real time by monitoring the content of Chlorophyll A. This device has the advantages of high sensitivity, low cost and easy to operate .etc.

Path planning is a key factor in intelligent transportation vehicle navigation system, compared to a variety of advantages and disadvantages of the path planning optimization algorithm. According obstacle distribution characteristics similar characteristics to the grid circuit resistor, proposed a Circuit Map path planning algorithm. The city's roads each segment was mapped to the circuit network, and the resistance of the resistor were mapped to with the Weighted sum of road length and width, and traffic density. This can be achieved by solving the circuit that intelligent transportation systems path planning and navigation services.

In order to guarantee the special vehicle capacity, quality of service protocol in computer network is referred, travel characteristics of special vehicle is analyzed. Put forward the special vehicle operation control scheme based on agent, analyzes the functions of each agent and collaborative way. Finally on the basis of this design the special vehicle priority security algorithm.

It designed a simple system device which can detect the concentration of melamine in pure milk in this paper. Using the visible-near infrared light source to irradiate melamine-contained milk solution, the reflection spectra would have obvious change at the wavelength of 500 nm with the increasing concentration of melamine in pure milk, and the reflection spectra are nearly overlapped at the wavelength of 1000 nm. Based on this principle, combined with the photoelectric technology and computer technology, collecting light at 500nm is used to determine the concentration of melamine, and collecting light at 1000nm is used to eliminate the Interference of other ingredients in milk. The experimental result shows that, when the concentration of melamine is not less than 3 , the relative error produced by the device is less than 1%. And the device can quickly detect whether the milk containing melamine in real-time and accurately show the concentration of melamine, which make the device have strong practicability.

To investigate the effects of grinding media size on the grinding kinetics of cassiterite-polymetallic sulfide ores, the ball grinding media with diameters of 25mm, 30mm, 35mm and 40mm were studied in a laboratory ball mill. The results showed that the coarse and fine particles obeyed the first-order grinding kinetics laws in the process of grinding and the ball grinding media with 35mm diameter had a significant advantage on grinding up the coarse particles and controlling the generation of fine particles, which could provide theoretical guidance for practical production so that the grinding effects would be improved effectively and the problem of cassiterite over-grinding would also be settled very well.

Nanometer materials are widely used in the modification of polymer materials such as polypropylene because of its unique performance. nanocomposite material,which expended the application field of polymer ,is a kind of new composite materials with high performance ratio and widely application prospect .This paper adopted the surface-initiated technology to coat and modify the surface of nanosilica,which solved the problem of the agglomeration and interface compatibility of the nanometer particles and improved its dispersion in the acrylic acid,then prepared SiO2/PAA nanocomposite .The composite was characterized by infrared spectrum and transmission electron microscopy (TEM) ,etc.The research results showed that the nanocomposite prepared by in-situ polymerization technology had higher toughness ,strength and more excellent comprehensive performance.

In recent years, recovering zinc from low grade oxidized zinc ore has been a matter of discussion. In this paper, the investigation for recovering zinc and iron from gossan ores was carried out. In generally, the conventional physical separation methods, such as flotation, gravity separation and magnetic separation, were used to treat the low grade ore, and flotation is the most commonly used method for beneficiation and pretreatment of oxidized zinc minerals. However, gravity separation and magnetic separation are used to deal with the gossan ores because of the special zinc oxide ore bearing iron 40.2% in this study. The effects of grinding fineness and magnetic intensity were investigated, respectively. The results show that the grade of zinc and iron increase slightly, and the best result is that the grade of zinc and iron are 13.35% and 40.25%, the recovery of zinc and iron are 53.45% and 52.19%.

The normal mode helical antenna (NMHA) is widely selected on RFID and wireless communication applications and often placed in a dielectric material for protection and miniaurization design. In this paper, the effects of dielectric materials with finite dimension on resonant frequency and impedance characteristics of embedded small NMHA were investigated. Three parameters related to the dielectric material were considered. Significant results were obtained by varying each one of these electrical dielectric parameters. It provides an effective guidance for designers to tune the antenna to desirable complex impedance when surroundded dielectric materials are employed.

The grinding kinetics are strongly affected by the grinding media size and style, in order to improve the grinding efficiency and solve the over-grinding problem of cassiterite in the process of grinding in cassiterite-polymetallic sulfide ores plant. A unique double-sphere grinding media has been designed and the grinding kinetics of this media with different diameters for grinding products of different size fractions have been investigated in this paper.

According to salt rock creep test data and strain variation regulation of a salt mine, salt rock creep parameters are obtained based on Burgers creep model fitting. Statistical study of the probability distribution of the salt rock Burgers model creep parameters is carried out by K-S, A-D and C-M test method, from which probability model for each creep parameters is obtained. To achieve the purpose of determining the optimal probability model for each creep parameters, considering the acceptable level of various test method to different hypothesis probability model, the author put forward the comprehensive optimal acceptance criteria on the basis of limited comparison method, the correctness of which is proved by test result.

In Hubei Province in China, About 15%-40% yield of Burley tobacco losses caused by mildew during air-curing period for High humidity and low temperature. In this paper, active solar utility system was first applied to condition temperature and humidity in the air-curing process. Forced convection solar collectors, natural convection solar collectors and air circulates system were applied in the solar Burley barns. The results showed that: The cost of the system was about 1226 ¥ per drying barn, but it could quickly increase the temperature and reduce the relative humidity of the barn, and the quality and yield were raised. The collector efficiency was about 18.8-24.9%. The average temperature of barn could be improved to 3-4 °Ceven in rainy days. The quality of upper and middle tobacco was enhanced by 11% to 13%; Yields increased by 18% to 23%; The income per acre added 371-392¥; the average income of tobacco increased from 10.49 to 10.87 ¥ per kilograms .

In order to research the injury of pedestrian collided with microbus windshield, the finite element model of pedestrian and windshield are established based on the characteristics of pedestrian collision with microbus windshield in traffic accident to simulate the collision process by ANSYS/LS-DYNA. In the condition of different impact velocities, HIC, TTI and stress intensity of pedestrian are studied in simulation test. The results illustrate that with the impact velocitys increasing the original impact energy, stress intensity, acceleration, HIC, and TTI increase. Also, the collision time is prolonged. Collision in head, the head of pedestrian would suffer serious injury with more than 29 km/h impact velocity. The chest would suffer serious injury with more than 25 km/h impact velocity in condition of colliding on chest.

The aim is to improve the convergence of the algorithm, and increase the population diversity. Adaptively particles of groups fallen into local optimum is adjusted in order to realize global optimal. by judging groups spatial location of concentration and fitness variance. At the same time, the global factors are adjusted dynamically with the action of the current particle fitness. Four typical function optimization problems are drawn into simulation experiment. The results show that the improved particle swarm optimization algorithm is convergent, robust and accurate.

In this paper, a series of novel halogen compounds, melamine halogen acid salts were directly synthesized by melamine and halogen acid in water phase. The chemical structures of melamine halogen acid salts were characterized by Fourier-transform infrared spectroscopy (FT-IR), elemental analysis and1H-NMR. Meanwhile, the thermal properties of compounds were investigated by thermogravimetric analysis (TGA). The TGA results showed that melamine halogen acid salts had good thermostability during polymer processing. Futhermore, limiting oxygen index (LOI) and vertical burning test were used to study the flame retardant properties of composites blended by melamine halogen acid salts and polymer. The results revealed good flame retardancy that flame retardant polyethylene with 2 wt% melamine hydrobromide in total 8 wt% flame retardants got LOI value of 29.7% and reached UL 94 V-0 rating.

In order to develop realistic water resources strategy, we initially analyze the situation of water resources in the United States which present a significant regional difference. Then on the basis of previous studies, we propose the cost formulas of water storage, movement and desalinization. By analyzing the practical application, along with pros and cons of the above three solutions accordingly, we consider that a comprehensive utilization of these measures will be the best water strategy for America to solve the water shortage problem. Later we apply the conclusion to a case study of Southern California, we propose an optimization model which aims to minimize the total cost of the water strategy, and then use Lingo to solve the problem. Results show that 5.946 billion cubic meters of water by transferring is the best way to make up for the water use gap in 2025 and the total cost is 2.94 billion dollars. Finally, we summarize the strengths and weaknesses of our paper. What needs to be emphasized is that our model can also be adapted into the analysis of other states, which shows great flexibility.