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The tensile strength, elognation and microstructure of alloy are respectively tested and observed after annealing treatment. The results show that the working rate the larger, the initial recrystallization temperature the lesser. The proper middle annealing process of Cu-Ag alloy with 80% deformation is 405°C×5h.

The tensile strength, elongation and microstructure of alloy are respectively tested and observed after annealing treatment. The results show that the working rate the larger, the initial recrystallization temperature the lesser. The proper middle annealing process of HSn88-1 alloy with 80% deformation is 460°C×5h.

In near space optical communication, the laser beam energy affects communication link distance directly, also laser beam quality affects the laser energy density, modulation efficiency, bit error rate (BER) of communication and other parameters. In this paper we have presented an experiment system of space optical communication, of which the transmitting power is 1w, modulation rate is 500 Mbps and link distance is 8 to 10 kilometers. Then the effects of optical fiber collimator, electro-optic modulator, optical antenna and other units on beam power loss, beam diameter, divergence angle and other parameters are analyzed. Last we put forward the way of increasing the laser transmitting distance and the optimization measure of system key unit.

The platform uses three-dimensional data modeling, visual simulation and spatial data storage to make the business of regulation center, operation and maintenance center and marketing and management center of Beijing Power grid implement visualized operation, and load the spatial information data, equipment data and operation data of Beijing power grid into the system platform, and the data is displayed with the form of graphic or image, which not only realizes managing space resource data in real three-dimensional scene, but also make the system operator to know the operation state of the system directly, and makes the control measures more effective. And the paper uses virtual reality technology to establish visual scene of ground to realize integrated visual display of power transformation, power transmission and power distribution, which not only makes the producers, managers and decision makers directly master the situation of production line in power station, but also realizes that producers and managers affiliate decision makers to formulate production plan.

The paper presents the first results of the Improved XCS in classification problems. We classify the classifiers into certain-right classifiers, certain-wrong classifiers and uncertain classifiers, and then analyze the difference between certain and uncertain classifiers. A new classifier attribute at is presented which denotes the ascending times of prediction error, the bad condition set is used to improve the robustness of the system. Several experiment results on binary and integral classification problems demonstrate the superior performance of the Improved XCS.

How to make good use of the limited energy to maximize the network life span is an important problem of the wireless sensor network. The life of WSN depends on the minimum of the residual energy of its nodes. A fair energy balance routing algorithm is proposed which uses the Ant Colony Optimization Algorithm (ACO) to balance the network energy distribution and extend the network life. The proposed algorithm utilizes the dynamic adaptability and optimization capabilities of the Ant Colony to get a tread off between the shortest path and the fair energy balance. Simulation results show that the proposed algorithm is good at balancing the energy, and it effectively extends the span of the network life.

In order to build WBAN devices and design WBANs, it is imperative to study the characteristics of WBAN channel and model the channel accurately. WBAN channel models are so different from the traditional mobile channel models and there are few publications on them. In this paper, we studied the statistic characteristics of the WBAN channel based on the IEEE 802.15.6 models. We focus on body surface nodes to external nodes, simulated the path loss models on 820 MHz and 2.36 GHz at both LOS and NLOS situations. We also used the Gauss model to fit the statistic results of the path loss and obtained coefficients of Gauss model.

Due to the special demand of energy control and balancing the energy of nodes in wireless sensor networks，multipath routing based on ant colony system(MACS)was proposed. The algorithm utilizes the self-organization，self-adaptability and dynamic optimization capabilities of the ant colony to find the optimal routing and suboptimal routing from sources to Sink．Simulation results show the algorithm balances energy consumption of nodes and extends network lifetime effectively．

Nodes in wireless sensor network have limited power supply and wireless channels between them are sensitive to interference. In order to make good use of the limited energy, a routing algorithm is proposed which uses the Ant Colony Optimization Algorithm to balance the load of the network and extend the network life, the proposed algorithm utilizes the dynamic adaptability and optimization capabilities of the ant colony to get the optimum route between the cluster heads．Simulation results show the feasibility and effectiveness of this algorithm．

The study of the characteristics of WBAN channel model is crucial, due to the fact that it is an important step to design wireless body area network (WBAN). WBAN channel models are so different from the traditional mobile channel models and there are few publications on them. In this paper, we studied the statistic characteristics of the WBAN channel based on the IEEE 802.15.6 models. We focus on body surface to body surface circumstance, simulated the path loss models on 400, 600 and 800MHz and studied the statistic characteristics of the path loss models. Finally, we used the Guass model to fit the statistic results of the path loss and obtained coefficients of Gauss model .

This paper introduces an adaptive adjusting FIR filter’s parameters (LMS) method and presents a system recognition model based on the adaptive filter theory. The adaptive filter is directly with adjustable coefficient h (0),h (1),...h (N-1).The unknown system and FIR model have the same input sequence. The simulation result confirms the feasibility of the model.

Wireless sensor network has features such as the limited energy of nodes and poor processing ability. A framework for mobile agent-based data fusion is proposed,whose routing strategy was implemented by using approximation algorithm. The theoretical analysis and experimental results show that the proposed algorithm is superior to other intelligent algorithms in terms of the solutions.It proves that the proposed approach has obviously prolonged the network lifetime.

Equalization technology is important in WBAN channels for resolving ISI problem. However, traditional algorithms, such as LMS and RBF are not suitable to be applied in WBAN channel, due to the fact that channels of WBAN are particularly time variable and have severe multipath effect. In this study, we proposed a novel hybrid algorithm by combining NFN and RBFN algorithms. Experimental results show better performance compared to both NFN and RBFN algorithms in prediction problem in WBAN Channels.

Image feature extraction and classification is increasingly important in all sectors of the images system management. Aiming at the problems that applying Hu invariant moments to extract image feature computes large and too dimensions, this paper presented Harris corner invariant moments algorithm. This algorithm only calculates corner coordinates, so can reduce the corner matching dimensions. Combined with the SVM (Support Vector Machine) classification method, we conducted a classification for a large number of images, and the result shows that using this algorithm to extract invariant moments and classifying can achieve better classification accuracy.

0-20wt.% PEEK reinforced PTFE composites were prepared by a cold pressing-sintering method. The tribological properties and surface morphology of the transfer films were investigated via a MRH-3 friction and wear testing machine and scanning electron microscopy (SEM) respectively. Results show that the wear resistance of PTFE composite is improved more than 670 times with the addition of 20wt.% PEEK and the lowest friction coefficient is obtained with 5wt.% PEEK. Surface morphology shows that the transfer film formed on the counterface becomes more and more uniform and continuous with the addition of PEEK filler, frictional trace on the transfer film suggests that abrasive wear occurred during the sliding process.

With development of wireless Internet, the interworking of the third generation (3G) and wireless Local Area Network (WLAN) has become a focus research. Fusion of 3GWLAN has complementary advantages. The background and scheme of 3G and WLAN Fusion are discussed. The security of Fusion was analysed. Presents two security Fusion schemes has given. The first is called a loose coupling, The second is called close coupling. Two schemes are complement each other, realize the 3G and WLAN user unified management and 3G signing based on user WAPI security mechanism of WLAN access, and protect the user privacy.

Because the sense of place of residential district are more and more important, the designer will face the subject how to increase the sense of place of residential district. This article analyses of the factors that increasing the sense of place of the district in where people live and taking Chengdu Phoenix habitat Residential Area for example, and obtaining the factors of the sense of place in residential area to embody the emotion of "home" concept.

Walfisch - Bertoni model is used to predict the average signal field intensity of the main street. The model considers the path loss of the free space, diffraction loss along the path, and the influence of the height of the building. There are six City parameters in Walfisch - Bertoni model influence communication quality. In this paper, the researches about path loss and its characteristics is under the case of considering two city parameters at the same time. Facts have proved that this case is more close to the actual that the wireless signal propagation environment. This paper mainly researched the path loss, probability density function (PDF) and cumulative distribution function (CDF) of the path loss.

An accurate three-dimensional flow passage model of the compressor has been created; the stress distribution of the main flow channel has been obtained. The aerodynamic force was applied to the impeller blades. Three kinds of loads were applied to the main blades and splitter blades. Modal characteristics of the compressor blades have been intensively studied.

Along with the development of information technology, the Wireless Mesh Network gradually unfolded itself. This paper presents the development of Wireless Mesh Network, the existing research results and safety performance analysis.

Concrete pavement joints are an important part of the cement concrete pavement, and joints are the weak link of the concrete pavement. It is also one of the main causes of early diseases and failure of cement concrete pavement. This paper summarizes the outcome of the predecessors, introduces the research status of the joints, and analysis the joint destruction and its cause from the point of view of the stress.

This paper doing research on the technology of multiple virtual human’s rendering. With the problem of too much triangular patches needed to be rendering ,make improvement on the technology of instancing based on GPU and combinate the method of LOD, put forward the algorithm of large-scale animated virtual human rendering based on instancing. This algorithm reduces the communicating overhead between CPU and GPU, raises the efficiency of large-scale animated virtual human rendering.

A monomer 4,4'-bis(β-hydroxyethyl)biphenyl (2BP) was synthesized by the Williamson reaction from 2-chloroethanol and 4,4'-biphenol. Then, the novel dendritic liquid crystal macromolecule (DLCM) containing biphenyl structure was synthesized with 2BP and 1,3,5-benzenetrimethylacylchloride as monomers by dispersion method. The structures of 2BP and the DLCM were characterized by FT-IR and 1H-NMR. The thermal stabilities of he DLCM were measured by TGA and DSC. The results showed that the DLCM had good thermal stability and the DLCM may have a higher phase inversion temperature.

To achieve the security inte-gration of 3G and WAPI based WLAN, a USIM based certificate distribution protocol is proposed. Two security integration schemes, i.e, loosely coupled and tightly coupled, are presented, which unify user management of 3G security architecture and WAPI, and realize WAPI based network access for 3G subscribers and identity privacy protection. The entity authentication and anonymity of the certificate distribution protocol is analyzed in CK model, and the results show that the protocol is provably secure.

Liquefaction is one of the most important damages in pile foundation under earthquake. However, it is very difficult to analyze. Numerical simulation of pile-soil interaction considering saturated sand liquefaction under earthquake is conducted using OpenSees program. In this model, the soil is divided into soft clay soil and saturated sand, and the single pile is embedded in the soil. The results show that the pore water pressure rises and the soil liquefied as vibration time increases. With the nonlinear of the soil develop, the stiffness, bearing capacity and the acceleration response of the soil and the pile decrease, while the displacement response of the soil increases. Therefore, it is necessary to consider the soil liquefaction in the design and analysis in the engineering practice.

Modeling the radio channel has historically been one of the most difficult parts of mobile radio system design. Channel modeling is the basis for the high-level network planning process (antennae heights, frequency assignment, base station subsystem parameter set, network architecture, etc... ). In this contribution, we will compare two of the most important outdoor macro-cell models, COST 231-WI model and ECC-33 model with simulation and measurement. The measurement is taken in urban areas.

The regenerator of Stirling refrigerator is normally installed a contact sliding sealing ring, but if the sliding sealing ring working hour is overlong, it would cause wear heavily, and reduce the service life. This paper focus on resolving this problem: use a clearance seal device, which without leakage under the high pressure test, instead of the sliding sealing device. Meanwhile, use the clearance seal device would eliminate contact wear which would cause the leakage losses. Therefore it is fairly important to establish a theoretical model to imitate leakage process in the clearance seal device, analyze the factors which influence clearance seal, and find a solution to improve clearance seal in Stirling refrigerator.

The 1st, 2nd and 3rd generations of hydroxyl-terminated hyperbranched polyesters (HBPE-1, HBPE-2, and HBPE-3) were synthesized. A3rd generation hyperbranched polyester (HBPE-3) was used as original crosslinking agent to prepared hyperbranched waterborne polyurethane dispersions (HPU). FTIR spectra confirmed that this reaction really took place. The experimental data indicated that, compared with the linear one, the hyperbranched HPU aqueous dispersions exhibited lower viscosity, and larger particle size. For the hyperbranched HPU films, mechanical properties were obviously enhanced.

Background: Studies show that rapid access to high altitude, the body inevitably will be different degrees of injury, more significant damage to heart and lung [1 ~ 3]. The high altitude hypoxia on the lung tissue to adapt to structural changes and hypoxia inducible factor-1α (HIF-1α) expression of the study rarely reported. The experimental area for a short time brought by the near sea level to higher altitudes rat lung tissue by light, electron microscopy and the expression of hypoxia inducible factor-1α changes were studied.Objective: To observe the altitude hypoxia on the ultrastructure of lung tissue and the hypoxia inducible factor-la (HIF-1α) expression.Methods: 50 rats were randomly divided into 5 groups, namely group 1 d Golmud (altitude 2 700 m), 2 d Tanggula group (altitude 5 000 m), 3 d Nagqu group (altitude 4 500 m) and 30 d Nagqu group (altitude 4 500 m), the control group (in Xi'an, elevation 5 m). 4 time-consuming experimental animals 1 d from Xi'an to the Golmud, Qinghai (altitude 2 700 m), 2 d to the Tibetan Tanggula (altitude 5 000 m), 3 d to the Naqu (altitude 4500 m), 30 d in Tibet Nagqu. Light and electron microscopy of the lung tissue samples, Western Blot method to detect the lung tissue of hypoxia inducible factor-1α expression, RT-PCR method for detection of high altitude hypoxic group, lung tissue expression of hypoxia inducible factor-1αmRNA change. Results and Conclusions: Acute hypoxia 2d Tanggula microstructure and ultrastructure of lung tissue apparent high altitude pulmonary edema, and 30d after hypoxic Nagqu group after high altitude pulmonary edema was significantly reduced lung tissue Western blotting, not Canon See HIF-1α protein expression, RT-PCR detection of HIF-1αmRNA in the 30d Nagqu group, a certain amount of expression, the other three experimental groups HIF-1αmRNA expression was not significant (P> 0.05), 30d Nagqu group HIF-lamRNA expression was significantly higher In the control group (P

Objective To investigate the plateau plains of arginine vasopressin (AVP) gene polymorphism population and hypoxic adaptation in the relationship. Methods Polymerase chain reaction and restriction fragment length polymorphism method, the indigenous Tibetan population and plains Han Chinese AVP gene polymorphism detection and analysis of genotype and allele distribution. Results Showed that 150 cases of native Tibetans in +22959 sites GG, GT, TT distribution of genotype frequencies were 46%,50.1% and 3.3%, while the plain Han people 60. %, 37.3 %and 4.7%, the difference was statistically significant (P

The project Expo Axis is one of the landmark buildings of Expo Shanghai 2010, and its structural safety depends largely on the security of the six Sun Valleys, which are the important components of the Expo Axis. The simulation of the whole process of collapse and collision of the sun valley under earthquake action is conducted in this article. In the calculation multiple nonlinear factors are taken into account, such as material nonlinearity, large displacement effect, self-contact collision among the structure members, contact collision between the structure and the ground, etc. Through analyzing the results, a reasonable assessment of the structure of Sun Valley’s performance under the supper-large earthquake is given out. This method can also offer reference to other similar large-span steel single-layer lattice structure’s performance analysis.

Oxidation kinetic of a Zr55Cu30Al10Ni5 bulk metallic glass (BMG) and its crystalline counterpart were studied under dry artificial air (20% of O2 and 80% of N2) at 673 K by thermogravimetry analysis (TGA) method. According to TGA profiles, the oxidation kinetic in both amorphous and crystalline states followed a protective parabolic law. However, the oxidation rates for the amorphous alloy were obviously higher than those for the crystalline alloy. Pseudo-grazing incident X-Ray diffraction (GIXRD) has been carried out to identify the oxides nature and their crystalline structure. Tetragonal-ZrO2 dominated the oxide scale formed on both alloys (BMG and crystalline) at T = 673 K; meanwhile, a slight amount of Cu was detected on the oxide surface of studied BMG alloy. The atomic diffusion mechanism was investigated using a two-stage oxidation treatment to study oxide scale growth kinetics. The studied specimens were oxidized firstly under dry artificial air and then under 18O2 isotopic tracer gas for 1.5 hours respectively at 673 K. The evident solute penetration zone and ion diffusion characteristic through the oxide scale were determined by Cs+ secondary ion mass spectrometry (SIMS) depth profile. The results showed the mechanism of the oxide layer formation of both alloys was not only due to Oxygen ions diffusion from oxide surface to interior scale, but also to an outward diffusion of Zirconium ions from substrate to oxide layer and the ZrO2 oxide growth seemed to occur at the oxide/gas interface in our studied case.

This paper introduces a new, visualized approach for including all the geometric feature variations in the tolerance analysis of mechanical assemblies. It focuses on how to characterize geometric feature variations in vector-loop-based assembly tolerance models. The characterization will be used to help combine the effects of all variations within an assembly in order to perform tolerance analysis of mechanical assemblies by employing commercial 3D kinematic software (e.g. ADAMS). Equivalent variational modeling, based on TAKS method, has been developed for modeling variations in 3D mechanical assemblies. Create a library of Equivalent Variational Joints (EVJs) to allow inclusion all kinds of variations in analysis, and allow the kinematic model to include both geometric and dimensional variation in a velocity analysis. EVJ, for use in tolerance analysis, was developed for commonly used 3D kinematic joint types, and was implemented with examples to explain their use to form Equivalent Variational Mechanisms (EVMs).

The isothermal initial oxidation kinetics of Zr55Cu30Al10Ni5 bulk metallic glass in glassy state (lower than Tg = 685K) and in surpercooled liquid state (Tg = 685 K < T < Tx=774 K) is investigated under dry air by thermogravimetric method in short-term stage (for 1.5 hours). A protective parabolic law is followed in glassy state, except at 573 K where a linear law is followed. The self-limiting oxidation kinetics evolves from a short linear stage to a steady mild growth stage in supercooled liquid state at 723 K, which is induced mainly by crystallization and by the fast growth of dense scale. The growth of the scale is dominated by the formation of tetragonal-ZrO2 (t- ZrO2) in the range of 623 K - 673 K in glassy state for 1.5 hours. The activation energy of oxidation is mainly piloted by the diffusion of oxygen ions.

A novel azobenzene optically polymer (P-DA) was synthesized based on the azo chromophore molecule, chiral reagent L(-)-tartaric acid, acryloyl chloride and methacrylate. The P-DA was characterized by FT-IR, UV-Vis spectroscopy, 1H NMR, DSC and TGA. The P-DA had high thermal stability up to its glass-transition temperature (Tg) of 110 oC and 5 % heat weight loss temperature of 199 oC. The UV-induced trans/cis photoisomerization and reflex-isomerization behaviors were investigated. The results indicated that the P-DA solution could undergo photochromism after irradiated by 365 nm UV light. The optical parameters: refractive index (n), the dielectric constant (ε) and thermal volume expansion coefficient (β) of P-DA were obtained. The thermo-optic coefficients are one order of magnitude larger than those of the inorganic materials, such as SiO2 (1.1×10−5 oC -1 and LiNbO3 (4×10−5 oC -1) and was larger than the organic material such as polystyrene (-1.23×10-4 oC -1) and PMMA (-1.20×10-4 oC -1). The conclusion had a little significance to develop optical communication.

Manufacturing is a major driving force and an important pillar for national economic development .It is also an important source to create national income. The current logistics model of manufacturing and the low level of development in logistics industry significantly restricted the industry prosperity and development, and affected the overall strength of the supply chain. The paper firstly explains the relevant research about industrial linkage and coordination degree, and creatively forms development paths of industry linkage between manufacturing and logistics. Then, the paper takes the development situation of the manufacturing and the logistics industry during the period 2000 to 2008 in China as the research object. It builds an evaluation model about coordination of manufacturing and logistics industry linkage in MATLAB, and analyze the change of coordination degree about the manufacturing and logistics of linkage by SPSS. Finally, it concludes the results of the paper in this study.

A novel polyelectrolyte (PLJY) was synthesized based on the azobenzene chromophore containing functional groups (-C=C-) and α-methacrylic acid by radical polymerization. The PLJY was characterized by FT-IR and UV-vis spectroscopy. The thermal property was characterized using the differential scanning calorimeter (DSC). The glass transition temperatures (Tg) was 179.1 oC and showed that the PLJY had excellent thermal stability. Influences of pH values on the UV-Vis absorption spectra of PLJY were studied and polyelectrolyte solution had good pH-sensitivity and H-aggregation behavior. The photoresponsive and thermochromism behaviors were investigated for the azo polyelectrolyte PLJY solution or film. By 256 nm excitation wavelength, the PLJY solution or film appeared photo responsive behavior. At high temperature, the PLJY solution had thermochromic behavior. These results showed that the polyelectrolyte had potential applications in optical information storage and optical switch.

A comprehensive tolerancing system is presented with its design principle, system architecture and key functions. The following functional modules, automatic generation of dimension chain, equivalent variational mechanism (EVM) modeling and visualized 3D tolerance analysis, are described in detail. Design intent is expressed by assembly tolerance specifications, which may be added to the model and used in computing predicted quality levels. A comprehensive method, based on equivalent replacement, has been developed for modeling variations in 3D mechanical assemblies. The models are constructed of common engineering elements: dimension chain, kinematic joints, assembly datums, dimensional and geometric feature tolerances, and assembly tolerance limits. The method is consistent with engineering design practice and is well suited for integration with commercial CAD systems. To make the tolerancing system robust and efficient, new functionalities are added to well-known CAD software and simulation environment. Tested by many samples, this system shows good robustness and practicability.

A novel azobenzene polyelectrolyte (ABAPE) was synthesized based on chromophore 4-(4’-nitrophenylazo) naphthol (NPAN), epoxychloropropane and α-methacrylic acid. The ABAPE was characterized by FT-IR and UV-vis spectroscopy. The aggregation behaviors of ABAPE were investigated based on different pH values by the UV-vis spectroscopy. The isomerization behavior of the ABAPE in DMAC solution was studied by 256 nm UV irradiation light. Attenuated total reflection (ATR) method was adopted and carried out the measurement of refractive index of the thin film. The thermo-optic coefficient (dn/dT) was -2.9228×10-4°C-1 and was bigger than inorganic materials such as silica glass, zinc silicate glass, borosilicate glass and the organic materials of polystyrene and PMMA. These results showed that the polyelectrolyte could be used to carry out optical storage and thermo-optic switch.

The isothermal oxidation behavior of Zr58Nb3Cu16Ni13Al10 bulk metallic glass (BMG) under dry air in the glassy state and the supercooled liquid state (SLS) was studied by the thermogravimetric method. The oxidation rate and thickness growth speed in the SLS were both hugely higher than in the glassy state. The oxidation kinetics of BMG in both states for 1.5 hours was different, the parabolic law was followed in the glassy state at 300°C and 350°C, contrarily the linear law was followed in SLS at 400 °C. After the oxidation for 126 hours in SLS, the oxidation kinetics possessed two stages, the linear stage and the parabolic stage. The diffusion of the Cu2+ ion and CuZr intermetallic alloys were detected by GIXRD.

The corrosion properties of Mg-Al-Sr alloy was characterized with comparison to AZ91D alloy. With the addition of Mg-Sr master alloy, the grain size of Mg alloy refined and the corrosion resistance was improved. The experimental results indicated that the formation of small amount of Al4Sr phase was favorable to improve the corrosion resistance. However, with the increase of Al4Sr stripy phase, the area ratio of cathode to anode will increase, resulting in the decrease of corrosion resistance potential.

Mg-Sr alloy was prepared by the vacuum synchronous reduction method at a temperature of 1100°C. The phase composition of the reaction product and slag was analyzed by XRD. Results showed that Mg17Sr2 and α-Mg were formed in the product while Ca2SiO4 and Sr2SiO4 existed in the slag. DSC-TG curves obtained from thermal analysis of the reduction process indicated that vacuum was an essential condition in the preparation of Mg-Sr alloy by synchronous thermal reduction method when temperature was below 1200°C.