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The hydroforming process of the aluminum alloy panel was simulated by the software DYNAFORM. The effects of process parameters (blank holder force, depth of panel and height of draw bead) on springback of the aluminum alloy were investigated. The max springback of the panel was analyzed by weighted scoring method. Then the process parameters were synthetically optimized for the max positive and negative springback. The results showed that the height of draw bead affects obviously the comprehensive springback of the panel. The optimization of the process parameters obtained by the orthogonal experiment can effectively reduce the max springback of the panel.

The static dent resistance performance of the aluminum alloy panel formed using viscous pressure forming (VPF) is studied by experimental methods. The successive load is used to cause the aluminum alloy panel dent in the static dent resistance test. The influence of the curvature radius and VPF process parameters on the static dent resistance performance is researched. Results show that the panel with the smaller radius has a larger stiffness and static dent resistance; the adequate drawing depth can optimum the static dent resistance performance of the double-curved panel and the drawbead also can increase the stiffness and static dent resistance.

Punching shear is a common failure mode occurring at the slab-column connection region of a reinforced concrete (RC) flat plate. Progressive collapse of RC flat plates poses a significant scientific question on the post punching behaviour of such a structural system. The challenge lies in the complex interactions amongst various internal actions including large unbalanced moments and shear forces. Existing numerical models are unable to differentiate the influence of each individual action within the connection region after punching occurs. Therefore, a new numerical model is required to model these actions individually as well as to evaluate their interrelationships. This paper thus aims to propose a numerical method to investigate the structural response of RC slab-column connections by using a micro model, based on a representative post punching failure experiment. In the micro model, concrete is simulated using solid elements whilst the reinforcement is modelled with truss elements. In this micro model, the constitutive laws and failure criteria of materials play a crucial role in describing the model’s structural behaviour. A typical structural response is discussed and a calibration method is established. Ultimately this study is expected to facilitate the development of an effective, yet simplified numerical model for future progressive collapse simulation of slab-column connections.

The temperature coefficient of the microwave dielectric ceramic materials is one of the important dielectric property parameters. A new method, which can detect the temperature coefficient of microwave dielectric ceramic material, is presented in this article. The test method and software buildup of the system are also introduced. The new system has the advantage in obtaining fast, reliable and high accuracy measurement performance.

This paper discussed the factors that affect the height of water fractured zone, and they were divided into primary and secondary factors, in order to construct a system that included factors that affect the height of water fractured zone. By using the BP neural network model, this paper chose the thickness of coal seam, roof lithology, tilt angle of coal seam, overburden hardness, working face length, advance speed and rock bulking to be the primary factors in order to simplify the model and accelerate speed. If the mining geological condition was clear, we could ignore the secondary factors. Prediction results showed that the simplified BP model could meet the accuracy of the height prediction of water fractured zone and the prediction method could provide technical guidance and a certain safety for coal mining under water.

With the wind farm data from the southeast coast this paper builds a two-stage combination forecasting model of output power based on data preprocessing which include filling up missing data and pre-decomposition. The first stage is a composite prediction of decomposed power sequence in which a time series and optimized BP neural network predict the general trend and the correlation of various factors respectively. The second stage is BP neural network with its input is the results of first stage. The effectiveness and accuracy of the two-stage combination model are verified by comparing the mean square error of the combination model and other models.

This system uses the MSP430F6638 and FPGA as the core, includes full bridge rectifier circuit, power factor correction circuit, Boost/Buck circuit and sample circuit. According to the sampling voltage and current value, The FPGA adjusts PWM wave duty ratio of power factor correction chip UC3854, completing single phase AC/DC conversion circuit with a voltage outer closed-loop and current inner closed-loop and active power factor correction (APFC). Test shows that the output voltage can stable in a setting value, with amplitude range ±0.05V, and when load’s impedance changes, this circuit can keep a small voltage adjustment rate and load adjustment rate. We use electronic parameter measurement device to measure the efficiency of AC/DC converter in a specified condition (voltage input Us=24V, current output Io=2A, voltage output Uo=36V), result demonstrates it’s a relatively ideal value. At the same time, under the control of UC3854, the power factor of alternating current input is 0.9734.And when we set the range of power factor between 0.8~1.0, The circuit can automatically adjust the power factor to track the set value.

Traveling wave in transit, wave head is easy to produce distortion and affected by environmental interference, so accurately measuring the head of traveling wave singularity occurrence time become extremely difficult. The key to improve the precision of traveling wave detection is to accurately capture the happening time of wave head of singular points. Recently, traveling wave singularity detection usually use wavelet, EMD-HHT transform technique, but both have mixing phenomenon, affecting the accuracy of detection. In this paper, we propose a new method that use Duffing chaotic oscillator to suppress traveling wave interference signal. By Matlab simulation and it is proved that this method can effectively suppress noise singular point. Meanwhile, we propose an anti-mixing EEMD-HHT wave head detection technology. Through simulation experiment and field test, it is proved that, compared with EMD, EEMD can more accurately identify the traveling wave arrival time, detection accuracy increasing by 1.52%.

ECG waveform has becoming a new kind of Biometric signal for person identification recently. The identification procedure was based on the establishment of person's own ECG waveform template, one beat of ECG waveform was used as analysis data, 15 persons were involved in the study. In the paper, several algorithms are compared for their ability to identify person. The algorithms are coefficient threshold method and Euclidean distance threshold method, their measurement was based on linear distance. Hausdorff distance threshold method as a non linear distance was also compared. Except this, SWM(support vector machine) was also introduced to do the identification work. From the experimental results, Euclidean distance threshold method and the Hausdorff distance threshold method reached same level of identification, the acceptance rate is around 76.0%, the correlation coefficient threshold method reached 86.0%. As to the SVM, its acceptance rate near 96.0%. Although the amount of experiment data was relatively small, but the result give the researching in good promising and better prospecting.

A new dioscin-bonded silica gel stationary phase with natural active ingredient for high performance liquid chromatography was prepared by one-pot reaction method, using 1,6-diisocyanate as the spacer arm. The structure of new stationary phase was characterized by solid-state NMR techniques, infrared spectroscopy, elemental analysis, thermogravimetric analysis and scanning electron microscope. These results show that the dioscin has been bonded to the silicia gel. The resulting stationary phase containes 127.6 μmol/g dioscin ligand. The chromatographic performance of this new stationary phase was evaluated by different kinds of solute probes. The results illustrate that the new stationary phase has a typical reversed phase chromatographic property, meanwhile it could present various interactions with solutes. The HPLC fingerprint of PNS(Panax Notoginseng saponins) API(active pharmaceutical ingredient) on the dioscin-bonded silica gel stationary phase was established. The mobile phase was consisted of gradient acetonitrile and water. The detection wavelength was 203 nm, the column temperature was maintained at 35 degrees Celsius, the flow rate was 0.8ml/min and the injection volumn was 15 μL. The contents of the 5 co-possessing components were determined simultaneously. A new material for HPLC was made by natural product. The using of dioscin-bonded silica gel stationary phase provides a new idea in natural products research.

Electromagnetic radiation has become a great threat to human health. In this paper, ferrite and graphite were main absorbing agent, which were prepared to a new type of anti-electromagnetic radiation gypsum board. The results show that the microwave absorbing properties of ferrite/graphite mixed are better than with ferrite or graphite single-agent mixed. The gypsum board with the graphite content of 5wt% and the ferrite content of 25wt% has the best absorbing performance, The effective band width less than-5dB of the samples is 7.1311GHz, and the maximum absorption peak-18.467dB.

The surface morphologies, chemical composition, phase composition, compactness, thickness and the corrosion resistance of porous anodic films prepared in the sulfuric electrolyte with different additives at 35°C were investigated by XRD, FESEM, EDS, drop method in this paper. The additives are including organic acids, polyhydric alcohols and rare earth (REE) salts. It is indicated that a porously anodic film with about 20 nm holes in diameter can be obtained by additives into the sulfuric electrolyte. The main chemical compositions of the anodic films are Al, O elements, and a small amount of S. The film after boiling water sealing is composed of boehmite phase (Al2O3·H2O) and alumina (Al2O3). The corrosion resistance of the anodic film can be improved by the coupling effect of the additives. The mechanism is discussed.

In this paper, we propose a novel and efficient read-write optimization scheme for flash memory storage systems, we have named RWF: Read-Write FTL. In the proposed scheme, we effectively connect Logical Sector Number, Logical Block Number, Logical Page Number, Physical Page Number and Physical Block Number. RWF through uniting log blocks and physical blocks, all blocks can be used for servicing update requests. The invalid blocks could be reclaimed properly and intensively, it can avoid merging log blocks with physical blocks. At last, through the simulation test on RWF and the comparison with other schemes, which demonstrate the RWF can effectively solve data storage problems, and it greatly reduces erase count of flash devices and efficiency improves the performance of flash memory storage systems.

Digital video, as a kind of large-scale resource, plays an important role in internet’s multimedia resources. Resource consuming is one of the major issues for extracting data from digital video. However, if it is possible to know the outline of a video by browsing several pictures describing it, that will save us a huge amount of time. Up till now, it is not common for video processing system using cloud environment (except video transcoding system). This demo shows an extensible video processing system based on Apache Hadoop cloud environment. Our system utilizes FFmpeg video encoder and OpenCV graphic processor. The basic process of building a video abstracting system includes segmenting scene, followed by exacting representative key frame. The source files of that video stores in HDFS, while the information of segmentation and key frame stores in HBase. In this way, fast searching can be achieved.

Coaxial polyaniline/multiwalled carbon nanotubes (MWCNTs) nanocomposites were prepared by ultrasonic–assisted chemical oxidative polymerization of aniline monomers in hydrochloric acid solution, in which MWCNTs with minimal defects was used as a template. Redoping of hydrochloric acid was achieved after the as-prepared nanocomposites were treated by ammonia. The nanocomposites were characterized by field emission scanning electron microscopy, fourier transform infrared spectroscopy, thermogravimetric analysis and cyclic voltammetry, respectively. The results indicated that HCl doped nanocomposites were better than HCl redoped nanocomposites on the thermal stability and electrochemical properties.

The characterization in microstructure, morphology and oxidation behavior of three iron-based coatings by Supersonic Arc Spraying (HVAS), were investigated by XRD, FESEM, EDS and thermal exposure in furnace in this paper. It is indicated that the three coatings are typical layer and compact structure. The coatings are composed of Fe (s.s) phase and kinds of ferric oxides, chrome carbides and/ or intermetallic phase distributing along the interface of lamellar layers. More Cr and Ti, Al elements can alternate the diameter and morphologies of the holes, resulting from the formation of oxides, carbides and intermetallic phase. The results indicate that SXTiAlC coating shows the most excellent oxidation resistance with 2.70 mg·cm-2 in mass gain, while that are 88.08 mg·cm-2 and 16.64 mg·cm-2 after 100 h thermal exposure at 800°C for LX88A and SXHCrA coatings, respectively. The oxidation behavior is discussed.

The characteristics including surface morphology, phase constitution, thickness and the corrosion resistance of the porously anodic films prepared in the sulfuric electrolyte with different additives at 35°C were investigated by SEM, EDS, XRD and electrochemical polarization method in this paper. The additives are organic acids, polyhydric alcohols and rare earth (REE) salts. A porous anodic film with about 20 nm holes in diameter can be obtained by additives into the sulfuric electrolyte. The main chemical compositions of the anodic films are Al, O elements, and a small amount of S. The film after boiling water sealing is composed of boehmite (Al2O3·H2O) and alumina (Al2O3) phases. The compactness and the thickness of the anodic films can be improved by the coupling effect of the additives, which increases the corrosion resistance of the film. The effect of additives on morphologies and corrosion resistance is discussed.

In this paper, an activator protein was isolated and identified from crude protein of Botrytis Spp which was separated from the soil of the wheat field with the method of mycelium recycling, breaking and centrifuging,etc. The activator protein appeared a single band on SDS-PAGE whose molecular weight was about 42kD. At the same time, it had a preliminary activity test and investigated on this activator protein. This study indicated that this activator protein is able to promote wheat germination after the deal with it, especially when the density is 3μg/mL, the seed germination is the best. So it is proved that the plant activator protein has really the biological function of improving the wheat germination.

The current situation, domestic supportive policies and problems of photovoltaic generation technology are analyzed. According to the roof resources and solar illumination conditions in Shanghai, feasibility analysis of distributed roof photovoltaic generation technology is presented in angle of economic feasibility. The influence of generation price subsidies on the internal rate of return and payback period is obtained and finally raising advices to improve domestic photovoltaic generation technology.

A novel polyaniline (PANI) coating doped with perchlorate ions was prepared on a stainless steel (SS) wire by a three-electrode system. Before electrodeposition, the SS wire was etched by hydrofluoric acid to enhance its surface roughness. The prepared PANI-coated fiber was used for solid-phase microextraction (SPME) of 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP) and triclosan (TCS) in water samples followed by high-performance chromatography with UV detection (HPLC-UV). The extraction procedure was optimized. The proposed SPME-HPLC-UV method provided a wide linear range. The limits of detection were 0.006 ng/mL for 2-CP, 0.005 ng/mL for 2,4-DCP and 0.04 ng/mL for TCS, respectively. It was successfully applied to the analysis of spiked surface water samples with the recoveries from 99.6% to 109%.

HCl doped Polyaniline (PANI)/multi–walled carbon nanotube (MWCNT) nanocomposites were first prepared by in–situ chemical polymerization of aniline monomers in the presence of MWCNTs with less structural defects, and then p–toluene sulfonic acid (TSA) doped PANI/MWCNT nanocomposites were obtained by a sequential doping–dedoping–redoping process. The morphology, microstructure, and thermal and electrochemical properties of the resulting nanocomposites were investigated by scanning electron microscopy, fournier infrared spectroscopy, thermal gravimetric analysis, and cyclic voltammetry, respectively. The effects of TSA as the secondary dopant on the microstructure and electrochemical properties were discussed. The results indicated that a significant improvement in the thermal stability could be achieved, while good electrochemical behavior could be remained.

When the bubble moves in the vicinity of a free surface, the movement will be affected by the buoyancy and the Bjerknes effect. Blake and Gibson proposed the criterion which determined the motion direction of the jet and the dynamics of bubble. They proposed the jet wouldn’t be formed in the condition that . Based on the potential flow theory, boundary element method (BEM) is used to calculate three typical examples in this paper in order to study the dynamics of the bubble under the combined action of the Bjerknes effect of the free surface and the buoyancy. It is found out during the analysis that the Blake criterion is applicable to predict the conditions that and .

To meet the technical demands of rapid assessment on small and medium earthquake damages, this paper presents the comprehensive disaster evaluation method of on-spot human-computer interaction survey and remote sensing image analysis based on the GIS technology support in the small and medium earthquakes. By making full use of the advantages of existing data, emphasizing on the automatical identification of the unique texture features of small earthquakes with a combination analysis on high resolution images gained from unmanned aerial vehicles (uav) and the seismic damages, the new method results in the rank distribution of earthquakes by gaining the experienced parameter of local small-medium earthquakes based on the analysis of regional characteristics of texture features of remote sensing images. It is concluded that the evaluation method is more accurate and efficient for small and medium earthquake rapid disaster assessment.

This study identified 19,831 publications to explore global trends of electronic commerce research during 1996-2012, based on all the subject categories of the SCIE and SSCI. A few significant global trends of EC research were revealed. First, proceedings papers and journal articles were the primary document types, contributing 12,200 and 6,707 publications respectively. Journal articles showed stable upward trends from 1996 to 2012. Second, the top three conferences contributed a 10.6% share of total proceedings papers and the top 20 journals published a 31.1% share of total journal articles. Third, “Computer Science Information Systems”, “Business” and “Computer Science Theory Methods” were the top three most popular subject categories.

Analyze and derive the relationship of each electrical quantity of the single-end fault location algorithm and present a fault location formula of two-end fault location algorithm. Through the simulation research of MATLAB/Simulink, when the fault occurs near in either end of the line, the ranging device near the fault point is adopted, fault distance can be measured with single-ended electrical quantities algorithm, when the fault occurred in near the midpoint of the line, two-end fault location algorithm is chosen to ensure the results’ accuracy higher.

To investigate progressive collapse behavior of reinforced concrete (RC) flat plate structures, a reliable and efficient numerical approach is developed in this study using spring connection modelling. This connection unit aims to simulate complicate punching shear behavior at critical regions surrounding the columns. Five springs are used as the connection elements: two for flexural and integrity steel bars and three for concrete contributions. The flexural and integrity steel bars embedded in the columns are modeled explicitly, which enables the model to present the structural behavior post punching shear failure. Bending and shear actions are represented by two concrete springs. The third concrete spring is assigned axial action property to restrain two end nodes of the connection on the model. In particular, the punching shear spring controls the connection unit when punching shear failure occurs. To apply the connection unit, the regions of slab-column connections are partitioned from the slab regions according to the critical shear surfaces. Then the connection unit links two corresponding nodes on the two edges formed from the partition. A physical experiment of a RC flat plate substructure under progressive collapse is simulated. Result comparison demonstrates that the numerical model has the capability to capture the structural behavior in progressive collapse. However, further improvement of the modelling technique is necessary to enhance numerical accuracy.

In this paper, we propose a novel and efficient flash translation layer scheme called BLTF: Block Link-Table FTL. In this proposed scheme, all blocks can be used for servicing update requests, so updates operation can be performed on any of the physical blocks, through uniting log blocks and physical blocks, it can avoid uneven erasing and low block utilization. The invalid blocks, in BLTF scheme, could be reclaimed properly and intensively, it can avoid merging log blocks with physical blocks. At last, the BLTF is tested by simulation, which demonstrates the BLTF can effectively solve data storage problems. Through comparison with other algorithms, we can know that the proposed BLTF greatly prolongs service life of flash devices and improves efficiency of blocks erasing operation.

This Currently, researches on formwork supporting system are mostly based on integrated stability, while the contribution of the cooperative bearing effects of the formwork supporting system and the concrete floor to the reliability of a structure is ignored. In this paper, the necessity of the existence of the formwork supporting system in the construction process of a structure’s roof boards is established by analyzing the cooperative effects of the formwork supporting system and the concrete floor of a subway transfer station under construction through double nonlinear numerical method.It is also concluded that flat paraboloid is the shape of the trend of the horizontal displacement of supporting formwork system under two-way load by using finite element analysis, and the open side of the paraboloid is opposite to the direction of the force, which is completely different to the decreasing trend from the top to the bottom of the horizontal displacement of the formwork supporting system under one-way load.

In order to the difficult forming sheet metal part with the vertical wall to be formed by the multi-stage incremental forming, the algorithm of the recognition and modify the difficult forming surface of the vertical wall is studied. The method for generation of the technological model for multi-stage incremental forming is also presented. The case studies show that the algorithm is feasibility.

In the article, the study focus on the computer aid finite element analysis of the rolled-steel pallet. The value of various parameters is determined by the force analysis according to the relevant standard in working condition of shock. Meshing the modal and defining the force and constraint are discussed before the simulation. The calculated value based on Ansys is very similar to the result in the actual situation, which proved that the computer aid analysis can be used in the rolled-steel pallet detection in order to decrease the cost and increase the accuracy.

Atherosclerosis is a risk factor of cardiovascular disease, aortic stiffness can be noninvasive estimated by measuring pulse wave velocity (PWV), and measuring PWV may help early detection of cardiovascular diseases. Therefore, a portable and easy-to-use prototype is developed for measuring PWV. This study acquires the data of pulse wave at two different arteries by two sensors. Then we can calculate the pulse wave transmitting time (PWTT) of the two pulse waves through extracting the feature points, respectively, and PWV can be obtained by the ratio of the distance between the two different measuring points and PWTT. In addition, a Bluetooth function is provided for data wireless transmission. Furthermore, a memorizer is embedded for long-time data storage so that the comparison of data becomes facilitated. Meanwhile, the data could be taken as an effective reference for the doctor to diagnose the illnesses. Experimental results show that the prototype is an easy use and portable PWV monitoring device for home use, and may help the doctor to analyze or diagnosis the cardiovascular diseases early.

Compared with vector control, direct torque control (DTC) spurned coupling idea and canceled circumgyration coordinates transform. By detecting motor’s stator voltage and current, along with calculating motor’s flux and torque in virtue of the instantaneous space vector theory, DTC controlled flux and torque directly according to the difference between the detecting value and design value. DTC also reduced calculation amount and overcomed the flaw that the system was disturbed by motor’s parameters easily, which were the problems in the vector control. On the basis approach mentioned above, this paper realized the system simulation using DTC. Simulation shows that asynchronous motor control has favorable ability of speed adjusting, short startup time, excellent stability.

A solvothermal method was developed to synthesize silicon carbide nanoflakes and nanowires through pyrolysis of polymethylsilane (PMS) at 550 °C in solution. Evidences from HRTEM, SAED, FTIR and XPS indicated that the products were amorphous nanostructures which mainly consisted of Si, C elements and trace amount O element. Owing to concrete quantum confinement effects, the unique nanostructures have strong photoluminescence centered at 410-430 nm under excitation wavelength of 350 nm

Firstly, taking into account the load forecasting error and uncertainty of wind power, the coal saving benefit and network loss of the reserve are combined into integrated coal consumption of thermal units. Then, the consistency constraints of reserve capacity are derived. On the basis of the work mentioned above, the optimal reserve distribution model for power system with large scale wind power integration is proposed. This model is used to compare the network loss, integrated coal consumption and the allocation of reserve before and after adding consistency constraints. Finally, simulation results on the IEEE-RTS24 system verify the effectiveness of the algorithm in solving reserve transfer between units, ensuring the fairness of market and providing a reference to dispatchers.

An optimal assignment algorithm of emergency power supply considering V2G is proposed with a necessary concern for its effect on society. Firstly, the comprehensive index weight coefficients are proposed according to the priority. Next, this paper establishes the network minimum total cost objective function based on constraints such as time and capacity limit, using symmetric triangular fuzzy numbers to simulate the uncertainties in emergency logistics on the condition that ensuring the normal work of EV in next day which is used to search for the best logistics path. Finally the optimal algorithm of emergency power supply is developed based on genetic algorithm. The model and algorithm are proved by a numerical example, and the study helps to reduce the investment and operating cost of power system and improve the ability of urban electric network in emergency situation.

Gram scale multi-layer graphene grown on polycrystalline SiC microspheres were prepared by continuously preparation method in argon through chemical vapor deposition process using liquid polysilacarbosilane as raw material. The observation of products obtained at different temperature confirmed the growth is temperature dependent process. The method could be developed to synthesis hybrid nanostructures based on multi-layer graphene grown on polycrystalline SiC microspheres.

Lithium iron phosphate particles were synthesized with supercritical water as a reaction medium, and the effects of temperature and pressure on particle purity and size were examined. A flow-through reactor was designed and set up with a SUS316L stainless steel material, and a large yield could be obtained with no preheated water involved. The products were recovered and characterized by X-Ray Diffration (XRD), Laser Particle Analyzer (LPA), and Scanning Electron Microscopy (SEM). Particles with an average size of 500nm could be obtained continuously.

This paper focuses on the design and application of the composite submarine cable online monitoring system based on Brillouin optical time domain analysis (BOTDA). It introduces two concepts of the system: the BOTDA technology and the finite element modeling method. Using ideas of modular design, the team developed the PC software on LabWindows/CVI. At the end of the paper, it describes the application of the online monitoring system, and then analyzes the data returned from the system.

With the prevalence of credit system, the stipulation of “academic warning” is written into the teaching management constitution by more colleges and universities. However, the present research in this stipulation is only limited to the simulation of multivariate normal distribution. This paper aims to improve the current setting of academic warning through Monte Carlo simulation of multivariate Copula functions, and to calculate more reasonable academic warning credit line. The result demonstrates that the accuracy is significantly improved, therefore, this approach can provide a new train of thought and universal method for colleges and universities to set specific standards.

Simulation method was applied to study the fouling behavior during the Micro-filtration of Semi-conductor wastewater. In the numerical model, concentration dependent physical properties such as suspension viscosity, density and generalized particle transport diffusivity were considered. The mechanism of suspension transition from liquid phase to gel phase was adopted to characterize the formation of membrane fouling. Fouling resistance distribution along the membrane surface was obtained from the simulation. The results revealed the mass transfer character in the concentration boundary layer and its influence on the formation of membrane fouling. Agreement between the simulation and the experiment results demonstrated the applicability of this numerical method in evaluating membrane fouling during Micro-filtration.

Small gasoline-powered generator is more widely used in an emergency, camping, disaster relief and other occasions. This paper describes a digital generator based on TMS320F28027 solutions. The program uses 2000 series Piccolo A as the master chip to control the work of the entire generator. It has the stable output waveform and better dynamic response at different loads, and it can provide reliable over voltage, over current protection.

In this paper, a novel image classification method, incorporating active learning and semi-supervised learning (SSL), is proposed. In this method, two classifiers are needed where one is trained by labeled data and some unlabeled data, while the other one is trained only by labeled data. Specifically, in each round, two classifiers iterate to select useful examples in contention for user query. Then we compute the label changing rate for every unlabeled example in each classifier. Those examples in which the label changing rate is zero and the label in the two classifiers is the same are selected to add into the training data of the first classifier. Our experimental results show that our method significantly reduced the need of labeled examples, while at the same time reducing classification error compared with widely used image classification algorithms.

Speech signal can be effect by the external interruption in the process of flight simulation, which results in the deteriorated speech processing performance in flight simulation system. To solve the problem, speech enhancement module has been developed using the spectral subtraction algorithm based on the flight simulation system developed by the research team. The module will improve the recognition rates and provide advanced anti-jam capabilities for the speech processing performance of the flight simulation system. The feasibility and validity of this speech enhancement module is validated by processing the interrupted speech signal. The work in this paper has laid foundation for the application of the speech enhancement technology in flight simulation system.

The solar blind NLOS ultraviolet Ad-hoc network communication bases on atmosphere scatter and absorption. An algorithm of channel sharing for the solar blind NLOS ultraviolet Ad-Hoc network is proposed to avoid conflict. The conflict nodes in the network are colorized based on the hybrid genetic algorithm, and then the network has a higher spatial reuse. The Simulation results show the algorithm of high-speed efficiency, thus having a better engineering practicability.

The acoustic emission signal of pipeline leakage is characterized by nonlinear and non-stationary. It is not feasible to extract the leakage feature signal in traditional signal processing methods. The leak locations can be detected by employing the improved empirical mode decomposition (EMD) to decompose the acoustic emission signal into several intrinsic mode functions (IMF), choosing IMFs containing leakage characteristics to be reconstructed, and doing correlation analysis. Experimental results show that the positioning accuracy of leakage detection is improved obviously.

This paper describes the use of one of the Matlab toolbox dynamic simulation tool Simulink simulation methods, and improve simulation speed, the simulation results analysis conducted in-depth elaboration. Also describes the use of SIMULINK simulation tools to achieve automatic control system modeling, analysis and design, simulation methods and Simulink-based video and image processing module sets into visualization, modular modeling idea.

Clarify the properties of derived design and complement design. The properties of Abstract: The definitions of derived design and complementary design are given. The method of constructing disjoint (13,4,1) design is proposed. The entire procedure of constructing (14,3,1) design ,(26,13,8,4,2) design and (13,9,6) design is also presented completely. 15 disjoint (13,4,1) design , 15 disjoint (13,9,6) design and 7 disjoint (26,13,8,4,2) design are obtained. The number of disjoint (13, 4, 1) design is proved.

The emphasis of this paper is to research dynamic characteristic of giant magnetostrictive actuator (GMA). First, a prototype of GMA driving by a Φ5×40mm GMM rod (Terfenol-D) is made and the experimental test-bench is set, the optimal pre-pressure of GMA is 129N, and GMA can made 39.5μm strain with 218N output force under 5A current. Then, the energy of electrical, magnetic and mechanical of GMA is studied, equivalent circuit of energy conversion is summarized. At last, dynamic characteristic of GMA is measured, and hysteresis of strain under high frequency is tested. The results show that the resonant frequency of GMA is 1200Hz, and the magnetostriction coupling coefficient up to 0.572. The output strain of GMA increase with the frequency increasing before resonant frequency, and GMA has max output strain (49μm) under 1A current at 1200Hz.

The basic concept of constructing the Steiner triple systems of order is described. The detinition of edges matrix of the complete graph is given. A method of constructing Steiner triple system of order is proposed. The errtire procedure of constructing Steiner triple systems of orderand is presented respectively, The enumeration problem of Steiner triple systems of order is discussed [1-1.

This paper describes the basic concept of constructing Steiner triple system of order and gives the definition edge matrix of a complete graph. It proposes a method of constructing Steiner triple system of order. The entire procedure of constructing Steiner triple system of order .It discusses the enumeration problem of Steiner triple system.