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SiCp/Al composite is widely used in the aerospace, electronics and automobile industries due to its ultrahigh strength and wear resistance. Surface integrity in the machining process can be influenced by tool corner radius. A finite element model is developed by DEFORM-2D to study on the effect of tool corner radius on residual stresses, cutting force and temperature in machining SiCp/Al composite process. The results show the large corner radius can improve cutting force, but hardly influence cutting temperature. Meanwhile, value of residual stresses is influenced by tool corner radius, but distribution of residual stress is not. The larger corner radius is, the greater the curve fluctuation of residual stresses is. And the large tool corner radius can effectively improve surface residual compressive stress.

To improve medical pure magnesium corrosion and wear resistance, the advanced plasma implantation technology were used to implanted medical pure magnesium with nitrogen ions under certain conditions, obtaining a certain depth of nitrogen ion implantation layer, and to study the surface properties of the implantation layer. The sample after ion implanted, the surface morphology, phase composition were analyzed, and have electro chemical corrosion tests, friction and wear tests, the results showed that: pure magnesium by nitrogen ion implantation, can be obtained a surface organizations which whole flat, compact, no surface cracks and holes; the surface implantation layer mainly composed of Mg and MgO, also found a small amount of Mg3N2, which is also the main reason for corrosion and wear resistance improved; compared to pure magnesium base, nitrogen ion implantation (process conditions: implantation energy: 40KeV, implantation dose: 3×1017ions/cm2, control temperature: 200°C) improved the corrosion resistance of the sample, but not obvious, about 1.2%; however, the friction coefficient decreased significantly, approximately 61%, the amount of wear also reduced significantly, about 74%, this means that, its wear resistance has been improved significantly. This study provides a reference to improve the surface properties of pure magnesium and be learned to develop a more reasonable parameters for further study of medical pure magnesium by ion implantation of nitrogen.

China's existing polymer-modified cement based compounds for waterproofing material standards are used for the tensile strength test and elongation at break test as the test method to evaluate the performance of the product extension. The elongation only reflects the extension ability of product, but cannot indicate the crack bridging ability of the product. In engineering applications, there is a requirement for higher bridging cracks ability of the products. In this paper, 9 samples of polymer-modified cement based compounds for waterproofing material were tested. Crack bridging ability was tested under the standards and methods in DIN EN 14891:2013-07. Tensile strength and elongation at break were tested according to the standards and methods in GB23445:2009. The crack bridging ability test results are between 0 to 2.08mm, in which 5 of them meet the requirements of greater than 0.75mm according to DIN EN14891:2013-07.The tensile strength test results are between 1.13MPa to 3.19MPa, the elongation at break test results are between 4% to 350%.The results show that higher tensile strength and higher elongation at break will have good ability of crack bridging. Samples with better crack bridging ability are close to type III product according to GB23445-2009 which requires tensile strength ≥ 1.8MPa and elongation at break ≥ 30%. Crack bridging ability directly reflects the product’s ability of crack bridging, and is more in line with the actual requirements in engineering applications. It is recommended that the crack bridging ability test method should be adopted in the formulation of China polymer-modified cement compounds for waterproofing material standards.

A series of new alloys including Pt-Ir-M (M=Zr, Mo, Y) were invented in this study. The physical properties, electrical properties parameters and thermodynamics database of the alloys were established. The phase structure and composition were analyzed. The calculation results were verified by experiments. The influence of solidification rate to microstructures, morphology and grain size of Pt-Ir-M alloys were analyzed. According to First Principle, the electronic structures, bonding characters and energetic stability of the alloys were calculated, the calculate result indicated that Pt-Ir-Mo is formed more easily than Pt-Ir-Zr and Pt-Ir-Y, and the formed Pt-Ir-Mo is more stable than Pt-Ir-Zr and Pt-Ir-Y.

The PCE has a great relationship with the work function of conductors in organic and printed electronics devices. And organic photovoltaics require an electrode with a work function (WF) that is low enough to either facilitate the transport of electrons in and out of various optoelectronic devices or collect electrons from the lowest unoccupied molecular orbital (LUMO) of a given organic semiconductor. In inverted organic photovoltaics, the ITO is normally used as cathode to collect electrons .By using PDDA deposition, the surface work function of ITO can be decreased by 0.3 eV, which is able to improve the electrons transport and the PCE in OPV, as it has been proved that the surface electronic potential of ITO is very sensitive to the presence of self-assembled molecular layers.

Research on the lightweight issue of DC-link is an important direction in modern AC drive electric locomotive. Canceling LC filter circuit is an important way to achieve the goal of lightweight. Therefore, this paper focuses on single-phase pulse rectifier without LC filter circuit. The generation mechanism of DC voltage ripple and network-side current harmonics in grid-side converter is derived. Then, aiming to eliminate the current harmonics, the N-order notch filter and PR controller are introduced to the double-loops controller. The loop of voltage outer controller with N-order notch filter can filter out the ripple of DC-side voltage effectively without affecting the dynamic performance of the controller system. Meanwhile, the loop of current inner controller with PR controller can achieve zero steady-state error control to both the fundamental and harmonic current, and can suppress the low order harmonics in the line current effectively. Analysis shows that replacing the original L2C2 filter circuit with software controller is feasible. Finally, the validity and effectiveness of the proposed scheme are verified in computer simulation.

Sustainable agricultural systems tend to have a positive effect on natural, social and human capital, while unsustainable ones feedback to deplete these assets, leaving fewer for future generations. Forage crop are critical to sustainable agriculture and contribute extensively to the world economy. Tremendous progress has been made in genetic transformation of forage and turf grasses in the past decade. The rapida dvancement of cellular and molecular biology and transgenic technology provides novel methods to accelerate and complement conventional breeding efforts. This review summarizes the latest advances of breeding forage crop and introduces the development of sustainable agriculture as well as perspectives the important role of breeding forage crop in development of sustainable agriculture in the future.

This paper calculated THI and K with GIS technology, and analyzed the tourism climate comfort level of East China based on the monthly average meteorological data of 30 years from 132 whether stations in East China. Results show that THI of East China decrease gradually from south to north, from low altitude to high altitude. The annual period of comfortable climate is longer when analyzed in terms of K rather than THI. The tourism climate comfortable period of East China shows significant regional difference, the maximum value distributed around Fujian province, and the minimum value distributed around Tai Mount in Shandong province. The predominant length of climate comfortable period in China is 5 months per year, while areas that have climate comfortable period for 10 months are most limited.

With the presentation of a fire accident caused by wire joint, this paper reveals the theory that large contact resistance at wire joint can induce high temperature, and eventually can cause fire. Through macro-examination and metallographic analysis about the melted marks of wire joint, it clarifies the formation mechanism of the melted marks, and the corresponding preventive measures which can prevent wire fires, provide a practical and reliable scientific basis to guarantee the safe operation of house power system.

When the wharf structure is completed, the temperature is different with the one at the usage period. The temperature difference will lead to the temperature strain, and create the lateral deformation and internal forces of the piles. Based on the assumption of the free temperature difference of beam-slab-system, the spatial simplified calculation model of the foundation pile and the stiff platform about the temperature stress in all-vertical-piled wharf is first proposed, the related calculation method is also given. The numerical example shows that the accuracy of this simplified method could meet the demand of preliminary design. In order to reduce the pile-top internal forces, the foundation piles should be arranged symmetrically. The pile-top internal forces are in direct proportion to the forth power of the pile diameter, with the increase of the pile diameter in all-vertical-piled wharf, the analysis of the temperature stress must be taken seriously.

Due to IGBT open-circuit fault of CRH2 EMU’s traction inverter, a method of its fault diagnosis with the three-phase current signals as detection objects is conducted. By applying the wavelet analysis, three-phase current signals are decomposed for four times. With the coefficients of each layer obtained, the energy values of layers are calculated as well as the vectors corresponding to failure modes. According to the vectors regarded as input and the expected output, a BP neural network is established. Through training the network, the parameters of network can be defined. In addition, to test and evaluate the performance of network, certain noise is added to the three-phase current signals. Simulation results show it is feasible for the fault diagnosis of traction inverter.

Thousands of tons of tar residue are gained as by-products in the production of toluene diisocyanate (TDI) using heavy solvent. It is very necessary to recycle the residue. In view of residue composition’s diversity, high purity isophthalic acid (IPA) was obtained as product by hydrolysis of diethyl isophthalate (DEIP) in the residue. Multiple factors which affected the yield of isophthalic acid were investigated. Suitable reaction conditions for industrial production were summarized: the tar residue was grinded to 100 mesh, mass ratio (NaOH: material) was 0.3:1, react in water for 3 hours at 90°C.

This paper is concerned with the analytical solution to lateral equivalent flexural rigidity for fiber-reinforced top-hat stiffened composite plate subjected to pure bending. The plate is divided into three parts consist of single-laminate, double-laminate and hat-laminate. After computing equivalent flexural rigidity of the three parts respectively, the overall rigidity is calculated based on the equality of relative rotation angle. An example has been adopted for analytical calculation and then been modeled by finite elements method. A comparison was made to verify the validity of analytical method.

The surface residual stress and integrity of workpiece have significant effects on the precision, the reliability and the fatigue life of the mechanical products. Since the most final surface integrity of workpiece depends on the grinding process mainly in engineering, this paper analyzed the surface residual stress of ground surface through the simulation works. Based on the finite element model and the thermal mechanical coupling field of the surface grinding for 45 steel was simulated and analyzed. The distribution of the residual stress and the effects of grinding parameters on residual stress were discussed. In addition, the measures for improving the residual stress in ground surface were put forward.

Novel biodegradable cellulose-based hydrogels were synthesized using a non-toxic crosslinker, polyethylene glycol diglycidyl ether (PEGDE). The effects of the crosslinker concentration and the ratio of sodium carboxymethyl cellulose (CMC) to cellulose were investigated. The results indicate that decreasing the amount of PEGDE and increasing the CMC to cellulose ratio resulted in better swelling. The 9:1 CMC/cellulose hydrogel with incorporating 3g of PEGDE had a swelling ratio of 230g/g. The synthesized hydrogels exhibited less swelling in NaCl solution due to a decrease in the osmotic pressure between the interior of the hydrogel network and the external immersion medium.

Two-axis differential speed control AGV was widely used in factory to carry cargo. AGV servo controller based on single DSP cannot meet the requirements of automatic loading goods, which greatly reduces the degree of automation. Software and hardware of three-axis AGV based on ARM9 and FPGA was discussed and designed to realize loading goods automatically, experimental results are also given.

Rural grid has large waste for its discontinuity in application. Li-ion battery, with feature such as small size, large power density, high single voltage, low self-discharge rate, low inner resistor and so on, has been applied in power storage system. The intelligent power storage system based on li-ion battery and super capacitor can effectively storage the extra power in the period of grid off-peak, and also could absorb the feedback energy when the velocity modulation system is braking, largely increases the use rate of energy storage.

Hybrid electric vehicle adopt hybrid electric power, can reduce the waster emission and energy consumption, which can solve the present problem of environmental pollution and energy consume. New type HEV based on composite electric power is proposed.To improve the performance of the system, Halbach PMSM is used instead of traditional PMSM, experimental results show its merits.

Much energy was created when hybrid electric vehicle braked down, Battery storage system can not absorb the energy efficiently due to its limitation, which caused energy waste. Regenerative braking system with super capacitor based on TMS320F2812 was brought forward in order to solve the problem, ADVSOR simulation results prove the system can improve battery’s performance and reduce engine emission pollution greatly.

With the increasing requirement on flattening the hierarchical structure of the military command networks, this paper studied the efficiency of the cross-level command style which is one of the most way to flatten current structure. We present a cross-level command model based on the tree network. According with it, we focused on two measurements, timeliness and invulnerability, to evaluate the command networks on different cross-level by the simulation experiments. Compared the results under two styles of attack strategies, the random attack and selecting attack, it showed that the new command networks with different cross-level are more efficient.

Halbach motor is a new type permanent magnet synchronous motor: unique permanent magnet structure makes its magnetic field unilateral and distributed sinusoidal, increases the magnetic density of air gap while decreases the magnetic density of rotor. It helps to raise the power density and efficiency of power, reduces the size of motor and the pulsating torque. The full-digital variable frequency adjustable speed AGV system with halbach motor based on the TMS320F2812 is designed, and its experiment result proves that it performed well and environment-friendly, saving the energy as well.

The fly ash of non grade with low activity can not be directly used in the cement concrete. After a lot of tests, several kinds of fly ash grinding excitation materials were chosen to be ground together with fly ash of non-grade and low activity. The studies show that three kinds of fly ash grinding excitation materials A, B, C can not only decrease the water demand ratio but also increase the activity index of the polished ash as well. All other indexes meet the requirements of technical specification standards for fly ash gradeI. Based on the effect of excitation activity and economic benefits, the fly ash grinding material B was chosen as the main active materials for the power plant to make excitation ash,the fly ash composite materials can be widely used in cement concrete with high activity index and great benefits, and the problems for the application of the long-term piled fly ash can also be solved .

Integrated starter alternator damper (ISAD) system requires motor: high-efficient, high-power density, low-ripple torque. Halbach motor is a new type of PMSM: unique permanent magnet structure makes motor have a sinusoidal magnetic field, can increase magnetic flux density of air gap and decrease magnetic flux density of rotor, which could enhance the power density and efficiency of motor as well as reduce its size. Software of Halbach motor design is given, also with the finite element analysis software with ANSYS language. Experiment proves the advantage of Halbach motor in ISAD system.

The surface of polypropylene (PP) nonwovens was modified by low-temperature plasma technology. Three factors influencing the plasma treatment, i.e. current, time and distance between nozzle and fabric surface, were studied by single factor experiments. The effect of hydrophilic modification of PP nonwovens was evaluated with water absorption. The variation of water absorption of PP nonwovens after plasma treatment was tested. The experimental results show that the plasma treatment can improve the water absorbability of PP nonwovens. The water absorbability increases with the increasing current, but decreases with the increasing distance from nozzle to fabric surface. With the increase of time, the water absorbability increases firstly then decreases.

Aiming at the imaging tasks scheduling problem on high-altitude airship under static conditions, some major constraints are analyzed and described, the constraint satisfaction model is constructed based on two optimization objectives: maximizing the task benefit, and minimizing the energy consumption. According to the characteristics of our model, an improved NSGA-II algorithm is proposed. Finally, the efficiency and feasibility of our improved model are verified in an experimental simulation, the application results and comparison analysis show that the proposed algorithm is effective and feasible.

This thesis is focused on the catalyst of ionic liquids. Firstly, chloroaluminate ionic liquid consisting of triethylaminia hydrochloride and anhydrous A1C13 was prepared, and its catalytic performance on the alkylation of benzene with 1-bromobutane was studied experimentally. The composition of the system was analyzed using gas chromatogram. The effect of such influencing factors were investigated as the constitute of ionic liquid,the dosage of catalyst, the mole ratio of benzene to 1-bromobutane, temperature,reaction time,the regeneration approach of the used ionic liquid catalyst. The results suggested that it helps to increase the conversion of propylene and the selectivity of 1-butylbenzene by increasing the mole fraction of AlCl3 in the ionic liquid, the amount of catalyst, the mole ratio of benzene to 1-butylbenzene, reaction time and by reducing reaction temperature. At optimal conditions of 66.7% of mole fraction of AlCl3 in the ionic liquid, l0wt% of catalyst with respect to benzene, 10:1 of mole ratio of benzene to 1-bromobutane and 313 .15K, both conversion of 1-bromobutane and selectivity of butylbenzene can reach 96.6% in 20 minutes. The activity of the catalyst can be basically remained after eight times reused. For the used ionic liquid, its catalytic activity can be partially recovered via adding some extra AlCl3 notwithstanding less satisfactory. The catalyst performance of ionic liquids on the esterification of ethanol with ethanonic acid was studied.

The whole optimization control and health maintenance of air compressor fleet system in coal mine is the current key problems urgently to be solved in pneumatic system application. The test system of wireless condition monitoring and control for air Compressor fleet is setup and the hardware structure of test system is put forward. Overall energy efficiency and piecewise energy efficiency concept of air compressor fleet system is proposed in this paper. The overall efficiency and the energy-saving potential of compressed gas supplying system are quantified by the method of Capacity on Demand. Network optimization control algorithm for the air compressor fleet system is proposed for the better management of the compressed air system.

Due to the merits of small size, high power density, high voltage, low self-discharge and low resistance, li-ion battery can replace traditional power battery and be used in AGV system. Over-voltage and low-voltage protection circuit, temperature protection circuit, equalizer circuit, self-locked circuit and voltage display circuit are designed; Equalization circuit can keep consistency of each cell used in the system; Self-locked circuit can make the system much more stability while the display circuit can ahcive the information of the power system. Experiments prove the effectiveness of these designs.

A type of closed-loop system model for capacitive MEMS accelerometer, with simple working clock , is presented in this paper. After establishing the force-feedback model and disgussing the magnitude of the feedback voltage, the readout interface IC for closed-loop detection is designed and the layout area of the ciruit is only 1435×2543 um2. Post simulation results indicated that the circuit has large detection range, high accuracy and linearity, giving evidence for the validity of our model.

A multi-objective optimization method was advanced to make the drag and structure mass minimum of horizontal stabilizer based the precondition of meeting flying qualities. After the optimization, the longitudinal stability reduced, the longitudinal control performance increase. This method has referential meaning for the design of horizontal stabilizer for Mini-UVA.

Seismic inversion methods include constrained sparse pulse inversion and band limit inversion, etc. Although resolution of the seismic inversion results is higher than seismic data, it does not identify thin interbedding sand body and confirm the development of reservoirs. In this paper, in A block of Indonesia adopted geostatistical inversion in reservoir prediction, which is a method of seismic inversion combining geological statistics simulation and seismic inversion. This inversion method can establish various 3D geological model with the same probability of rock properties and lithology and it obey all seismic, logging and geological data. Using statistical regularity and seismic inversion technique we can obtain more fine reservoir model and finally reach the purpose of identification of single thin sand layer.

The grinding heat directly affected workpiece surface in the grinding process and it might produce some defects such as crack and burn. Meanwhile wear debris generated in the grinding process could easily embed grinding wheel blowhole and caused clogging and passivation. So it was particular important to avoid defects and improve the grinding workpiece surface integrity effectively. This paper established an incompressible turbulent fluid spray model based on the study of the existing airflow and the grinding fluid distribution in the grinding zone. Then according to different grinding fluid supply parameters established the two-phase gas liquid spray flow model by using CFD(computational fluid dynamics), simulated and calculated the model, compared the mass flow rate of the grinding fluid flow field with different spray distances, heights, speeds and spray angles in the grinding zone and determined the most reasonable spraying jet position. At the last, through researching on the workpiece surface integrity experiment, it provided an experimental basis to determine the most suitable spray jet position and verify the rationality of supply parameters selection.

The typical characteristic of stoning band coal seams is of multi-layers and low permeability, so fractured vertical well is usually used in the CBM development of this kind of coal seams. As far as the reservoir simulation of vertical fractured CBM wells is concerned, the fracture characterization technique is of great importance. Taking the vertical fractured pilots in F coal measures of Bowen Basin in Australia as an example, this paper will illustrate the application of fracture characterization technique in reservoir simulation. Its highlight is to scientifically characterize the shape of hydraulic fractures and quantitatively describe the reservoir permeability improvement after fracturing through “MULTX” of grid conductivity with Tartan grid model, thereby determining key parameters for the reservoir simulation of fractured vertical wells and providing a scientific basis for establishing CBM development plan and forecasting ultimate recoverable reserves.

The complexity of geological conditions results in ambiguity and uncertainty when interpreting geological data, bring difficulties to geological modeling, so quantitative evaluation of uncertainty of various geological parameters is important to establish accurate geological modeling. M coalbed methane field in eastern Australia was selected as an example to explain this process. The parameters and these uncertainty ranges were discussed firstly. And then, the impacts on calculated reserves of parameter uncertainty were analyzed. A better effect was attained in M coalbed methane field with this method.

Silicon carbide substrate has been widely used in semiconductor lighting (LED), integrated circuit and microelectronic, optoelectronic devices. According to the former study, a series of the fixed abrasive lapping platen has been developed. The material removal rate (MRR), surface roughness and surface flatness of lapping SiC single crystal substrate (0001) C surface are studied using fixed abrasive lapping. Compared with the results of the free abrasive lapping, the surface flatness of SiC single crystal substrate (0001) C surface after lapping with the fixed abrasive lapping is better than that of the free abrasive lapping, the MRR of lapping with the fixed abrasive lapping platen is higher than that of the free abrasive lapping and the surface roughness (Ra) of lapping with the fixed abrasive lapping is lower than that of the free abrasive lapping. The study results show that there are some scratches on the sample surface after lapping with the fixed abrasive lapping. There are some hills and pits on the sample surface after lapping with the free abrasive, but without scratches. The height difference of the surface profile lapping with the free abrasive is much larger than that of fixed abrasive lapping. The research results can provide a reference for studying the fixed abrasive lapping platen, the lapping process and lapping mechanism.

Carbonate rock fractures can be automatically interpreted with ant tracking technology based on ant track algorithm. Application by using ant tracking technology in the carbonate reservoir fracture interpretation and reliability verification with FMI fractures shows that ant tracking technology can not only interpret fractures good on plane and profile, but also has a good reliability.

Coal bed methane (CBM) is a kind of natural gas that generated from coal and disseminated organic matters during the stage of diagenesis and coalification, which mainly composed of methane and hosted in coal seam by free, adsorbed, and dissolved forms. Genetic, reservoir type and occurrence condition in CBM are different from traditional reservoir. And the high-produced development wells in CBM aiming to drill more coal seams with high quality therefore needs to be analyzed in the methods that are different from traditional reservoir. 3 important factors including the study on correlation and elevation depth of coal seam roof and floor in section and areal by using well-seismic ties, outcrop boundary based on coal mine data and distributions of CBM reservoir properties in 3D model are needed for high-produced development well analyze in CBM. Application in Australia CBM project shows this methodology is very successful for the development well design with high production.

Based on the analysis of coring, logging and experimental data, fine evaluation on Fort Copper Coal Measures (FCCM) of Early Permian Blackwater Group in north Bowen Basin of Australia has been done. FCCM is a potential coal measure. Eight coal seams exist in FCCM. Laterally, they develop steadily. Seams of FCCM characterize interbedding with partings, high ash content, high gas content and mediate-low permeability. The content of partings, which are groups of siltstone, mudstone and tuff, ranges from 15% to 55%. The cumulative thickness of pure coal ranges from 40 to 60 m. The ash content ranges from 20% to 70%, averaging 45%. Coal seams gas content is as high as 7% to 15%, benefitting from the dense rock block effect on the top and bottom, as well as the interplayers. The permeability ranges from 0.1 to 10 mD laterally. Parameters above show FCCM has good developing potential. Western slope of Nebo syncline is suggested as the favorable area, considering its good developing factors such as shallow buried depth of coal seams, relatively high permeability and effective gas preserve environment. Meanwhile, gas in partings can be considered in collaborative development strategy. Developing gas along with ash will be the focus of future development evaluation.

In this paper, we choose the data of 24 capital cities of Chinese Mainland, with information on PM2.5 and the meteorological conditions, using the Mixed Effects Model to analysis the Pollution Characteristics and Influence Factors of PM2.5 in Chinese main capital city. The results show that the PM2.5 level has a significant seasonal characteristic; the level of PM2.5 in winter is higher than that in spring. And the weather conditions also have significant effects on the PM2.5 level.

In this paper, the liquid distributor performance for the falling film evaporation process was tested, and the relationship between the liquid height and flow rate were studied in the experiment. The results showed that the liquid height of liquid distributor is proportional to flow, liquid distributing hole diameter and flow, but inversely proportional to liquid distribution aperture. Overflow may be present at a high flow.

In recent years, with the BIM technology application matures in the field of construction engineering in our country，BIM is becoming more and more widely applied in the field of building water supply and drainage design, the effects of it is becoming more and more profound. In view of this, in this paper, the application of BIM technology in building water supply and drainage engineering design, as well as the present problems of the BIM are analyzed.

CuNiCoBe alloy and CuCoBe alloy were cast by the vacuum inductive melting technique, and were heat treated under certain parameters. By using optical microscope, sclerometer and conductivity meter, the properties of two alloys were investigated after heat treatment. Experimental results show that the process of 980 °C for solid solution and three hours of aging at 450 °C is the best heat treatment for CuCoBe alloy, while 960 °C is the best solid solution treatment temperature for CuNiCoBe alloy with the same aging measures. Ni is beneficial to improve the hardness and conductivity of alloys, and CuNiCoBe alloy has better strength, hardness and conductivity than CuCoBe alloy at different temperatures, and two alloys all have a conductivity mutation increase near 450 °C. CuNiCoBe alloy and CuCoBe alloy soften respectively at 464 °C and 471 °C.

Theoretical studies have shown that the generation of the hydraulic fractures reduces or even reverses the stress anisotropy near the fractures and results in increasing the complexity of fractures. A finite element model was established in which the pore pressure elements were used to simulate the behavior of porous media and the pore pressure cohesive elements were adopted to catch the characters of hydraulic fractures. A special fracturing manner was adopted to create complicated fracture networks by reducing or even reversing the stress anisotropy between fractures. The geometries of hydraulic fractures, strains, stresses, pore pressure distributions and fluid pressures within the fractures are obtained. The results of the model are fit well with the corresponding theoretical data. The simulation results show that the stress anisotropy is reduced by the generation of the hydraulic fractures, multiple parallel transverse fractures of horizontal well even reverse the stress anisotropy in some place of the reservoir. The simulation results validate the feasibility of the theoretical studies and the expected complex network fractures could be created by adopting special fracturing manner.

Micromouse is a small autonomous robot, which must navigate itself through an unknown maze from the start to the destination, the main challenge for micromouse is to solve the maze and find the optimum path. Detailed design of best-path finder was given. According to the different dash mode combination, dash path of micromouse in complex maze was analyzed. Motion command generator is developed to generate list of the motion commands in order to guide the robot dash from the start to its destination.

Photovoltaic (PV) generation is widely used to solve energy shortage and environment problem. Since the output current of the solar cell will change with the sunlight irradiation, the power of the solar cells are not stable, so there is a need of a storage equipment connected to the PV system. With the characteristics of high efficient energy storage and quick response of the power exchange, the superconducting magnetic energy storage (SMES) can be used to meet the balance between the grid and the PV. A SMES and PV subsystem are connected together with the DC bus, which have less power electronics elements and can control power quality efficiently than linked with the AC bus. This hybrid system is composed of a DC/AC converter on the grid side, a DC/DC converter with the PV arrays, and a DC chopper with the superconducting magnet. A detailed model of the hybrid system is built with MATLAB/SIMULINK. Simulation results with and without SMES connected to the grid-connected photovoltaic system are presented, compared, and analyzed. The results of simulation demonstrate that the SMES system can maintain the DC bus as a constant value which can contribute to the stability and reliability of the grid-connected PV system.

In recent years, advanced small nuclear power reactors, namely small modular reactors (SMRs), gained widespread attention. In areas where energy can’t be provided by large scale reactors and the nuclear power plants with large scale reactors can’t compete with the non-nuclear power plant technology, SMRs, as a versatile distributed integrated energy source, which result in expanding peaceful applications of nuclear energy, have enormous potential. This article describes the characteristics and analyzes prospects and challenges of SMRs.

The nuclear safety became the more important after the Fukushima accident. The development of nuclear safety culture is one of the most effective methods to improve the safety. Also the assessment shows the level of the nuclear safety culture. The nuclear safety assessment model is described. The assessment model was described from its time and space, and it was also discussed from macro and micro levels. The internal and external environment parameters are considered and the assessment of different levels of safety culture is described. According to established principles of nuclear safety culture, the selection rules of the different levels evaluation indicators of nuclear safety culture are discussed too. And it is pointed that the assessment of nuclear safety culture is a long time project and an integrated system.

Nowadays, the strained-Si technology has been used to maintain the momentum of semiconductor scaling due to its enhancement performance result from the higher mobility. In this paper, the influence of ionizing impurity scattering, acoustic phonon scattering and intervalley scattering to strained-Si (101) material is discussed.In addition, a calculation of the electron mobility in Strained-Si (101) material is made using the average momentum relaxation time method described in Ref [1]. The results show that the electron mobility increases gradually for both [001] and [100] orientations while for [010] orientation increases rapidly with the increasing Ge fraction x.[1]

The Alfresco development tool, which includes Apache Tomcat, MySQL and WebService, is an open platform for building a functional database system in a Java website. In order to improve the enterprises’ management efficiency in specialized industrial townships, a micro-information system based on Alfresco development tool has been proposed. In the construction of the micro-information system, Alfresco database exhibits great superiority in network database architecture, data query with Lucene search engine, data management and data security. In this paper, the general design ideas, functions, key technologies and realization methods of the Alfresco database are introduced.

The reactor pressure vessel is an unchangeable component of the light water reactor. To some extent, the life of the pressure vessel depends on the fast neutron fluence. In addition, the fast neutron fluence is an important parameter for radiation protection. So, the fast neutron fluence is one of the main parameters which should be verifying calculated by the reviewers. The verifying calculation of the fast neutron fluence of one reactor pressure vessel is presented in this paper, and the standard deviation between the verifying and designing calculations is lower than 10%. The reasons for the deviation are discussed.