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In order to further improve the performance of node positioning system and intrusion tolerance in Wireless Sensor Network (WSN), taking advantage of the redundant information within multi-hop sensor networks, a secure location algorithm which based on node hops, consistence aggregation and gradient descent (HCAGD) was put forward in this paper. In which the ideology of Hop-based node positioning algorithm was used for getting reference positioning information; the gradient descent algorithm was used for position estimation.

In view of the LLC series resonant converter topology, it is well known as suitable for small and medium power application, the stabilization of output voltage and the environment of step-dowm. The scheme is proposed for a kind of the step-up DC/DC transformer based on LLC resonant full bridge. The detailed design method is given. The 3KW prototype is built. The experimental results show it has the characteristics of the constant current discharge, wide working frequency and high power desity, as well, the feasibility is verified.

In wireless sensor network, there are several links from one node to another, selecting the high quality link from the links is an important basic research. As a general algorithm, the typical link selection algorithm is usually used in selecting the high quality link, but the typical link selection algorithm needs lots of data packages as the testing samples. But the energy of a wireless sensor network is limited; therefore, the typical link selection algorithm is not suitable for wireless sensor network. The paper puts forward two new Bayesian link selection algorithms. Simulation results showed that the news algorithms have better performance than typical link selection algorithm in the case of small samples.

Cloud computing has a nature of dynamic, virtualization and opening since it made. All kinds of large-scale cloud security incidents makes frequent cloud environment safety has been questioned. In order to ensure the security of cloud environments, intrusion prevention technologies trusted computing ideas proposed by combining intrusion prevention framework model based on trusted computing environment under a cloud. The model departure from the principle of intrusion prevention, access to behavioral characteristics, and then gradually normalize these features determine the weight of each feature heavy user node's credibility after the draw. Then it use a variety of cloud cluster server engine to detect defense and integrated decision analysis and cluster analysis to make timely cloud fast, and change the traditional intrusion prevention for their own business, to detect the status of the defense lag for cloud users with the maximum safe limit intrusion prevention services, but also to ensure that the cloud can withstand attacks, so the cloud and cloud users bidirectional safety effects.

An integrated ramp generator is presented in this paper. For traditional implementations, the amplitude clamp is realized with zener diode to limit the output voltage to ±VZ, while the zener diode is not available for standard CMOS process. The transmission gate is utilized to make the output voltage in the determined range. The reference voltage is provided by a bandgap voltage reference with temperature compensation, which guarantees the temperature stabilization of the frequency of the ramp generator. The ramp generator was fabricated in a commercial CMOS process. The frequency of 44kHz is achieved under the power supply of 3.5V, and the frequency variation of 41kH to 46kHz with the power supply of 3.3V to 5V.

A multiplexer with split devices for high channel isolation was proposed in this paper. The multiplexer is the most essential circuitry for multi-channel video signal acquisition systems. In the multi-channel applications, high isolation performance is required basically for the efficient signal processing. The noise propagation between channels is unexpected. The split devices technique is employed in the design work. Redundant transistors are inserted between the split cells to realize the noise grounded. This multiplexer is simulated and verified in the commercial CMOS process, and the isolation of more than 70dB was achieved. It has been embedded in a multi-channel analog signal processing system.

Since numerous parts and various faults of CNC machine tool, the mapping model is proposed to represent the complex relationship between faults. Then some matrices are used to process the mappings model. Finally, the priority of the fault sources is sorted by the fault localization algorithm based on the matrix above. Besides, the case of ram feed system of CNC boring machine tools FB260 illustrates the performance of mapping model based on fault diagnosis.

Under the background of that NGN is coming into practice,the article uphold the scientific recognition spirit and external developing attitude to describe the distinct viewpoint about latest network development in two sides on different technology level. First,Based on the analysis of the key technical issue of the NGN,discover the essential substance of integration of the unified network,and point out the truth that the independent media-stream network ,not the integration network,to be the future one that lead the video service to the user in coming future. Following,starting from more fundamental position,the article state that the current technology architecture , which based on the point-to-point linear thoughts, has leads the network into a unbroken bottleneck. We must take a new and more society-suitable way,the face-to-face transfer architecture to fulfill revolution of the network communication technology.

A data acquisition and control system for a safety valve test bench with high pressure and large flow rate, was developed based on the host-slave architecture, which takes an Industrial Personal Computer (IPC) as host computer and a Programmable Automatic Controller (PAC) as salve computer. The hardware architecture and software design of this system were introduced in detail. This system was verified by the experiment, and the results indicate that it can fulfill the requirement of data acquisition and control with high speed and long distance. This study can provide reference for many automation control fields.

On account of low convergence of the traditional genetic algorithm in the late,a hybrid genetic algorithm based on conjugate gradient method and genetic algorithm is proposed.This hybrid algorithm takes advantage of Conjugate Gradient’s certainty, but also the use of genetic algorithms in order to avoid falling into local optimum, so it can quickly converge to the exact global optimal solution. Using Two test functions for testing, shows that performance of this hybrid genetic algorithm is better than single conjugate gradient method and genetic algorithm and have achieved good results.

This paper deals with the problem of braking process modeling. A subway train braking process simulation software is built, which composes of a GUI and a underlying model. The underlying model consists of a train model and a brake system model. The train model is simplified and built by assembling subcomponent element models of a railway vehicle. The brake system model is simplified and built based on experimental data in order to reduce computational effort. The GUI of the software can be use to input model parameters, display simulation results, and store simulation data. As a result of the simplifications of the modeling process, the developed software can perform real time simulation.

Silicon steel magnesium oxide is a coating material used for preparing oriented silicon steel. In this paper, The preparation methods of silicon steel magnesium oxide and research progress of high quality silicon steel magnesium oxide preparation technology were introduced. The use of abundant brine resources in the preparation of silicon steel magnesium oxide was prospected.

In view of poor accuracy and slow calculation of the traditional on-line handwriting signature verification, an on-line handwriting signature verification based on Early Abandon Dynamic Time Warping (EADTW) was designed and implemented after numerous researched. The training template followed the mechanism of benchmark signature, while the certification part adopted EADTW algorithm. The experimental results showed that compared with on-line handwritten signature system based on DTW (dynamic time warping), this new system not only greatly reduced cumbersome and repeated calculation, but also obviously improved the accuracy, The bigger the test sample is, the more obvious the advantage is.

With the rapid development and widespread use of Internet, readers, especially scientific researchers, depend more on Internet than on traditional library services for necessary information. The Web access of libraries has begun to lay more emphasis on digital reference and consultation services. More importantly, this new type of service is becoming the focus of many scholars research at home and abroad. In this paper, we design a library digital resources management system based on the semantic Web technology, and analyze the access control model in our system by the semantic Web.

In order to achieve the intelligent dissemination of remote sensing image, the primary task is to establish a suitable user profile. In this paper, we proposed a novel approach of modeling user demand preferences, and took into account the multiple interests and the time factors. And we presented some computing methods of feature preference including time, space, image parameters, etc. At last, the simulation example shows the feasibility and effectiveness of the designed user demand preference model.

The research status of high purity magnesium oxide preparation is introduced in this paper. First, process for preparing high purity MgO is summarized, the global and domestic production status of high purity magnesia is also described. Finally, the problems and disadvantages of current MgO preparation methods are concluded, also development direction of preparation method basing on brine utilization in the production of MgO is put forward.

In order to promote the comprehensive utilization of salt lake brine resources, magnesium carbonate tri-hydrate (MgCO3·3H2O) was synthetized by low-temperature hydrothermal technique using purified MgCl2-rich brine and ammonium hydrogen carbonate solution as raw materials, the orthogonal experimental as method. The morphology could be tuned by changing the operating parameters. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the structures and morphologies of the products. The results show that the optimum conditions are as follows : reaction temperature is 40-50°C, n (Mg2+):n (HCO3-)=1:2.2, pH value is 8.8-9.0, stirring speed is 130 r/min, aging time is 3h, reaction time is 70 min. Magnesium carbonate tri-hydrate synthetized is one-dimensional acicular with good settling performance. Average aspect ratio could up to 29.60.

PVP/[Sr (NO3)2+Mg (NO3)2+TEOS+Eu (NO3)2+Dy (NO3)2] composite nanofibers were prepared via electrospinning, the effect of different electrospinning parameters on the composite nanofibers morphology were investigated. The results revealed that diameter of the composite nanofibers increased at first and then decreased with the increasing of voltage, and the properties of the spinning solution (viscosity and surface tension) increased gradually, but the conductivity decreased at first and then increased with the increasing of PVP content. SEM analysis indicated that its easy to get a good morphological and uniform composite nanofibers when the voltage was 13 ~ 15 kv, inorganic salt content was 5% ~ 6%, and concentration of PVP was 15%.

With the rapid development of the information age, computer software develops toward systematization and complication. In application areas such as commerce, finance and medical treatment,the performance of software is attracting more and more attention which even becomes one of the important factors to determine whether users are willing to use a piece of software. Currently, static checking tools are mostly designed to check the code errors but pay little attention to the performance problems. In order to detect the defects in source code that may cause performance problems, this paper designs and achieves a performance testing tool based on static analysis method. The experiments of detecting several open source projects using our testing tool demonstrate that it can quickly find the defects in source code with high accuracy rate. The result of defection removing shows that it can significantly reduce the memory consumption of software, and it can effectively improve software performance.

This paper aims at establishing the empirical equations of the qualitative relationship between the inspection periods of the grinder rods eccentric wear of the rod-pumped well and its influencing factors and putting a hypothetical test of it to find out the scientific evidences for the solutions to the eccentric wear wells on the basis of multi-linear regression equation.

This paper makes a strength verification of the chief components of a new hydraulic motor to find out that the design of this new motor meets every standard and this finding will lay a solid theoretical ground for relative experiments.

One-degree-of-freedom ten-bar mechanism is a novel mechanism designed to clear loose debris for the search and rescue robot, which involves only one motor to generate the sweep motion. This paper established the kinematic model for the mechanism. The effects of the adjustable parameters on the tips trajectory are analyzed. From the results, a set of optimal parameters are obtained.

For the presence of high energy consumption and high emission in ceramic production, combining with the energy-saving and emission reduction targets of the National Twelfth Five-Year Plan, the advantages of oxygen-enriched combustion relative to normal combustion are analyzed. Concerning the new scheme of the internal burner distribution and new requirements made by combustion control method, the application of oxygen-enriched combustion technology in ceramic roller kiln is studied. The architecture and internal burner distribution scheme of ceramic roller kiln are improved in this study, and a novel combustion control method for oxygen-enriched combustion is used in the combustion experiment. Experimental results show that, with oxygen-enriched combustion, it can achieve complete combustion of the fuel, the flame characteristics conform the firing process requirements, and reduction of NOx emissions with proper O2 concentration.

Magnesium hydroxide is an environmental friendly flame retardant with high flame retardancy and low smoke non-toxic characteristics. In this paper, the flame retardant effects of magnesium hydroxide was introduced, the production application and technology experiment of magnesium hydroxide flame retardant was studied. Meanwhile, the development trend of magnesium hydroxide flame retardant prepared from concentrated seawater or brine in China was analyzed.

The research status of crystallization process and crystallizer of gypsum is introduced in this paper. Progress in 3D mathematical simulation of crystallizer based on Fluent is summarized, and the application of the 3D model in the construction and optimization analysis is also described. Furthermore, the prospect of Fluent applied in the design and optimization of gypsum crystallizer is introduced. Finally, the potential and prospect of Fluent basing on the 3D mathematical simulation of crystallizer in the production of gypsum is put forward.

Amine-functionalized mesporous silicas ((referred as NH2MS)) were synthesized by grafting with ethylenediamine. The obtained materials have been characterized by N2 adsorption desorption measurement (BET). Adsorption behaviors of the adsorbent for lead (containing effects factors, kinetics, isotherms, thermodynamics) were investigated. The result indicated that the obtained particles possessed mesoporous structrure. The Pb (II) adsorption isotherm and kinetic data fit Freundlich model and the pseudo second-order kinetic model respectively. the adsorption of Pb (II) onto NH2-MS was an enothermic nature.

This paper presents a low-voltage differential operational transconductance amplifier (OTA) with enhanced DC gain and slew-rate. Based on the current mirror OTA topology, the optimization techniques are discussed in this work. The proposed structure achieves enhanced DC gain, unit gain frequency (UGF) and slew-rate (SR) with adding four devices. The design of the OTA is described with theory analysis. The OTA operates at the power supply of 1.8V. Simulation results for 0.18μm standard CMOS technology show that the DC gain increases from 60.6dB to 65dB, the UGF is optimized from 2.5MHz to 4.3MHz, the SR is enhanced from 0.88 V/μs to 4.8 V/μs with close power consumption dramatically.

In this study, the methods for combining statistical energy analysis (SEA) and the finite element method (FEM) for the vibration analysis of structures are studied. Using the two methods simultaneously isnt entirely extend a primarily low frequency method, the finite element method, and high frequency method, SEA, to the mid frequency region are addressed. This approach is intended to extend the frequency range for a FEM based vibration analysis . A new finite element elementl for elevated slab ballastless track is proposed in which the new model can be used for modeling the track structural constituents of elevated slab ballastless track. Using finite element method and Hamilton theory, the coupled equation of vehicle-track-bridge can be established. In calculating example, both the rail displacement induced by single four-layer beam model. Specifically, it showed that the method yields very good result and high performance in the numerical example of previous research.

According to the problem that the existing radar signal feature cannot effectively express and analysis its characteristic, a description method of radar emitter signal feature based on improved kernel density estimation is proposed. This improved kernel density estimation algorithm combine the selection of fixed window and variable window's width to achieve the window's width automatic adjustment value between the different estimation points based on the sample distribution. Then the probability density curve using kernel density estimation algorithm as radar emitter signal parameters characteristics stored into database.

According to the problem that the existing radar signal recognition method cannot effectively identify the radar signal, a new recognition method based on kernel density estimation is proposed. First using kernel density estimation gets the probability density curve of radar emitter signal parameters, then storing the cures into database as the characteristics, in the end a radar emitter signal recognition algorithm based on template matching is proposed.

The passive direction finding cross localization has got great achievement and has been widely used in military and civilian fields. Currently, the researches on passive localization have focused on AOA, TDOA and FDOA. In our system, the passive direction finding cross localization is more effective and useful. We use two UAVs to locate a single source. We apply the geometric method to analysis positioning accuracy. In order to study the performance of a passive direction finding cross localization, MATLAB is used to simulate the result. Finally, the simulation results and performance analysis provide operational technical principle for such a system.

With the continuous advance of mobile Internet applications and deepening of the mobile node based multicast applications are rapidly expanding, which prompted about IP multicast technology moves towards greater efficiency requires rapid expansion. This detailed analysis of the current source mobile support the technical characteristics of the pros and cons of various options, from mobile multicast nature of the fundamental dilemma facing the Institute and gives a general conclusion. Meanwhile, according to the technical characteristics of the mobile anchor point MAP, as a starting point, the initial build a more comprehensive source mobile multicast algorithm, given the basic principles and operation points, so show a good efficacy with, the extension movement of multicast frame shape.

The probability distribution of the filament number of each cocoon layer (FNCL) in the raw silk by fixed number of cocoons reeling process was discussed. The probability distribution and statistic characteristic in stable reeling state were given. Computer simulation of reeling process was undertaken to verify the applicability and theoretical results. The model of stochastic process and the analysis results possess universality.

The extensive use of plastic film has caused serious environmental pollution. In this paper, the fully degradable cotton mulching film was produced from waste cotton fiber by wet papermaking process. The breaking strength, tearing strength, degradation rate, transparency, air and moisture permeability of the cotton film samples were tested and analyzed. The results show that the cotton mulching film has better mechanical properties, light transmittance, and excellent degradation characteristics.

New yellow phosphors, Eu2+ and Zn2+ co-activated Sr3Al2O5Cl2, were prepared by solid state reaction technique, and their photoluminescent properties were investigated. Sr2.6Al2O5Cl2:0.20Eu2+, 0.20Zn2+ shows broadened the excitation band in near UV range and intense yellow emission under 400 nm light excitation by introducing into Zn2+. The single yellow light-emitting diodes were fabricated by combining InGaN-chips with Sr2.8Al2O5Cl2: 0.20Eu2+ and Sr2.6Al2O5Cl2:0.20Eu2+, 0.20Zn2+, intense yellow light can be observed by naked eyes from the yellow LEDs. Hence, the phosphor Sr2.6Al2O5Cl2:0.20Eu2+, 0.20Zn2+ may be applied in fabrication of phosphor-converted light-emitting diodes.

With the rapid development of air transportation industry, many air traffic controllers are facing overload, which brings potential danger to the flight safety. In order to reduce the workload of air traffic controllers, this paper studies sector optimum partition of terminal airspace. Firstly, airspace topology structure is built to describe the relation of key way points, legs and air routes. Power polygon divides the terminal airspace into several units, the workload of each way point can be calculated. Then the sector optimum partition mathematical model is built. A kind of permutation and combination algorithm is used to recombine the units, the objective function value of each unit is regarded as optimization function, and the optimal solution can be worked out in combination with the Particle Swarm Optimization. At last, an example of Beijing Terminal Airspace sector optimum is given, which shows Particle Swarm Optimization is an effective method to be applied into sector optimum partition based on way points workload.

With the speedy development of Auto-industry, CAN-BUS technology is becoming more and more mature day after day. This paper makes a study of the application of CAN-BUS technology in lighting control systems and failure finding model while making an analysis of the characteristics of the application of CAN-BUS technology in Auto-motive Network which paves way for the further studies of CAN-BUS technology.

In order to reduce air traffic controller workload, optimized terminal sector partition was studied. The terminal way point capacity evaluation model was built, power polygon divided the terminal area into several units according to the vital way points, each unit workload could be calculated by the European method “RAMS”, and the sector optimum mathematical model was built. One improved ant colony optimization was adopted to solve the model. At last, an example of one terminal airspace sector partition was given. The results show it is an effective method to be applied into sector optimum partition based on way points.

The path planning relates to the safe movement and navigation of the Autonomous Underwater Vehicles (AUV). This paper discusses the way of real-time path planning for autonomous underwater vehicle based on tracking control lyapunov function. The simulation conducted on H300 illustrates the effectiveness of proposed method.

Building the model of assembly system in virtual environment, analyzing and evaluating assembly system performance by use of system simulating technology, can optimize parameter and configuration of assembly system ahead of production plan in order to optimize production process and improve production efficiency. An example is given to illustrate the process of modeling and simulating the engine assembly system based on the FactoryPrograms software.

The use of electromagnetic relief valve with high pressure and large flow rate in hydraulic system is usually easy to bring vibration and noise issues, especially while water or high water based fluid (HWBF) is used as the fluid medium. In this paper, a HWBF electromagnetic relief valve with a cushion valve was presented and its simulation model was built based on AMESim software. Through simulation, it is found that the cushion valve can significantly reduce the peak pressure gradient of the electromagnetic relief valve during unloading process compared with that without a cushion valve. This research provides a new solution for solving the vibration and noise issues of a hydraulic system with electromagnetic relief valve.

A constant temperature range of the heating system plays an important role in the thermosonic bonding process. Heating block will provide enough heat for the heating system. In the paper, the thermal model of heating block and heating system were calculated by finite element method, and then some important conclusions were obtained. The change of temperature and thermal stress of block with the reference value of x and y was obtained. And an optimal structure of block for right temperature was built. The temperature distribution, thermal displacement and thermal stress distribution of the heating block and heating system were disclosed. The relevant change trends of temperature and thermal stress under the different load of temperature were investigated. These results can help improve the reliability of the heating system used in the thermosonic bonding process.

This paper makes use of the method of computational fluid dynamics (CFD) to group the Hydraulic muffler of network grid and makes a fluidic analysis of the rectangular wave input signal of the hydraulic muffler without intubation noise absorption effect. The result manifests that the employment of CFD simulation technology to hydraulic muffler can provide evident theoretical support for further development and study of hydraulic muffler, and is possible to lay a foundation for continuous studies of the hydraulic muffler.

The IDEF0 method can comprehensively and clearly describe the production line design data streams, the material streams and the relationship among the function activities, may guarantee the standard design and lay the solid foundation for the system implementation smoothly. Using the IDEF0 method to describe the function of the production line design flow, it can satisfy this complex large-scale system analysis and design request. It aims at optimizing the manufacturing of automotive parts to be more scientific and consecutive.

This paper is aimed to reach such a conclusion that the result gained from the analysis of the micro-vibration of coupled-pendulums made by optimal control theory is as consistent and effective as with that from other approaches, by the virtue of writing out the Lagrange equation of the micro-vibration of coupled-pendulums with the external force and analyzing the system by using control theories.

Based on 2-D PFC, non-circular particle with direction was constructed and specimens with different distribution of long axis orientation were established. Loads were applied in vertical direction. Changes of fabric such as the long axis orientation, particle contact direction and particle contact force in the process of loading were analyzed. It was shown that the larger angle of the loading direction and the long axis orientation, the greater strength of specimen and more anisotropic. It was proved by the numerical analysis that tendency of particle contact stress direction is the micro – mechanics reasons of soil’s anisotropy under loading.

In order to study the two-phase flow field in the SLG continuous powder surface modifying machine for non-metallic material, which have been widely used in the powder engineering of China, a three-dimensional CFD model is developed to make the numerical simulations of the inner gas-particle flow field based on the industrial SLG-3/600 type modifying machine. By the help of the Fluent software, the gas velocity field, pressure field, particle concentration field and moving trace of the two-phase flow field are obtained. The simulation results indicate that these fields are distributed non-uniformly in the SLG modifying machine. Besides, a shortcut phenomenon is observed during the moving of the particles. The numerical simulations can not only depict the flow characteristics inside the SLG modifying machine, but also present useful reference to the mechanism study and optimal design to further improve its structure and working parameters in the future.

Safety valves play very important role in protecting the safety of hydraulic support in coal mine. However, its development is greatly limited by the corresponding test bench for the dynamic experiment. In this paper, an experimental system for testing the dynamic performance of the safety valve with rated pressure up to 50MPa and rated flow rate up to 2000L/min, is introduced. Based on AMEsim software, modeling and simulation on the designed system is carried out. Some parameters of the system are also analyzed and their influences to the tested valve’s dynamic performance are obtained by simulation. It is found that the designed system, which adopting the combination of a piston and a plunger cylindersas well as accumulators, can fulfill the demands of the relevant standard. Among all the investigated factors, both the volume and pre-charged gas pressure of the accumulators have optimum values matching with the other parameters of the system. The stroke of the plunger cylinder, the rated flow rates of the cartridge valve and its pilot control valve, are required to be higher than a certain value to avoid negative effects on the dynamic performance of the tested valve. The research presented in this paper is helpful to the design of the test system.

We present the design and fabrication of metamaterials, and investigated the normalized power transmission properties of four metamaterials at different frequency in terahertz regime. We compared the power transmission performances of four types of metamaterials microstructures, and analyzed their transmission differences.

A hybrid method combining FE and SEA was recently presented for predicting the steady-state response of vibro-acoustic systems. The new method is presented for the analysis of complex dynamic systems which is based on partitioning the system degrees of freedom into a ‘‘global’’ set and a ‘‘local’’ set. The global equations of motion are formulated and solved by using the finite element method (FEM).The local equations of motion are formulated and solved by using statistical energy analysis (SEA). The power input from the global degrees of freedom. This paper deduces the theory for the beam element , and Train-Ballastless Track-Bridge System provides an application, and it showed that the method yields very good results .