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In this paper, the TiAl/Ti laminated (MIL) composite was fabricated via hot-pack rolling of the as-forged Ti-43Al-9V-0.3Y (at.%) plates and commercial Ti6Al4V (wt.%) sheet at 1250°C and then annealed at 90°C for 6 hours. The composite was analyzed by XRD and SEM techniques, respectively. Results showed that the interface between Ti and TiAl in the composite was consisted of four different microstructure areas and the phase constitutions for each area were: area 1: acicular β-Ti and α2 phase; area 2: acicular α2 phase; area 3: acicular α2 phase and B2 matrix; and area 4: acicular γ, α2 phase and B2 matrix. The fracture toughness of the TiAl/Ti MIL composite was tested, showing that the KIC value was about 38.35MPa·m1/2 at room temperature and higher than that of the pure Ti-43Al-9V-0.3Y alloy, which had a value of about 24.72 MPa·m1/2. The possible toughening mechanism for the TiAl/Ti MIL composite was discussed.

The modeling and optimization of machine tool’s dynamic performance remains to be a grand challenge in machine tool design. In this paper. In order to identifying the concentrated modals of a horizontal machining center, a combined experiment modal analysis method is proposed. A FEA dynamic model accurate in frequency and mode shape is built and verified by comparing with EMA results. Based on the model the optimization of frame structure is made, Simulation results shows the optimized frame enhances the dynamic performance of machine tool.

The paper analyses the theory and practice about the construction waste recycling in a meticulous and deep going way based on reverse logistics combining with present social development circulation economy current situation,then brings forward the operation pattern about the construction waste recycling based on reverse logistics,on the basis of household electrical appliances and electronic products recycling reverse logistics model, this paper put forward the system model of the disposal of construction waste based on the recovery of the third party reverse logistics service providers.Also,the paper makes an explanation about the problem and measure into practice,and provides theory and practice for the construction waste recycling.

As to the problem of blind recognition for convolutional code, the existing recognitory methods’ principle and process are summarized, and they are simulated and analyzed with Matlab. Four methods are introduced for the recognition of generation polynomials, and the comparison of these methods shows that the Euclidean algorithm works better at low BER, while the method based Walsh-Hadamard transform has a better accuracy when BER is as high as 10-2.

This paper introduces the application of IOT technology in the communication room monitoring and asset management in Hubei electric power company, consists of the design of general construction, hierarchical structure and functions. Target for the effective management of communication room power and environment monitoring, communication resources and site operation, applying monitoring and communication features of IOT, to make fast and reasonable configuration of communication resources at benefit maximization, support for the information level of communication room operational & maintenance.

Double PWM welding power source can restrain the net side current harmonic. In order to suppress the transient when the intermediate DC link voltage fluctuation, generally adopt the method of increasing capacitor capacity, the disadvantages of this approach are: slow dynamic response, large volume, low service life, high cost of equipment. Therefore put forward a kind of double PWM welding power source based on feed-forward control power, using the power of feed-forward can effectively inhibit the intermediate DC link voltage fluctuation, based on the control method of the power system has a high power factor, good dynamic performance, simple and easy, good application prospect.

This paper accomplished a system of high-rise building’s fire monitoring system based on CAN bus. It is applied in avoiding the harm of leakage current , over current and short circuit, and protecting electric power distribution circuits and electrical equipment, thus to prevent the occurrence of electrical fire. The monitoring system can detect phase current signal and the leakage current signal, and can display real-time and alarm. It also can proceed network service and complete the distributed remote control and fault diagnosis. Practice shows that the system the characteristics of high precision, safe and reliable, low rate of false positives, easy operation and maintenance, etc .It can satisfy the demand of large high-rise building electrical fire.

Rapid prototyping technology can generate parts directly from the three-dimensional CAD entity data, hierarchical algorithm is a key link in rapid prototyping manufacture. In this paper, mainly used a hierarchical approach in RP equipment,for the study aimed at three commonly hierarchical algorithm (hierarchical algorithm based on STL model, direct sliced of CAD models, Smart Slice based on STL model) by Perspective, trying to provide a reference for the stratification algorithm of RP system by comparison of the three tiered approach,This paper argues that the Smart slicing algorithm based on STL model is more accurate stratification algorithm

In this paper, we proposed a scheme to reconstruct the synchronous scrambler placed after a direct sequence spreader. The scheme was first based on the assumption that the spreading code was known and then extended to the unknown situation. The reconstruction algorithm took advantage of the properties of spreading code that was used to spread the input information sequence. We got a property that helped to detect the multiples of the feedback polynomial. The simulation results proved the validity of the proposed algorithm.

Sequence detection is used in many algorithms and applications. Sequences are different depending on different demands. In the process of floating-point CORDIC coprocessor design,data are need to change from floating point format to fixed point format. This process is necessary to detect the number of consecutive zeros. We design the leading-zero-counting algorithm to achieve this function, and this conversion process is completed in a very fixed short time, to ensure the needs of the floating point CORDIC coprocessor.

In order to insure the consistent wave loads in hydrodynamic calculation and structural analysis, the treatment of nonlinear roll damping in roll motion, wave torsional moment and structural analysis are studied. The nonlinear roll damping moment is applied to the structural model by means of the equivalent nodal forces. Taking a supply ship and a FPSO as example, the calculation results show that the problem of torsional moment distribution divergent on the bow and the unbalanced structural model is improved greatly, which would be helpful to provide the reliable basis to design the structures.

In semantic Web, extensive reuse of existing large ontology is one of the central ideas of ontology engineering. Ontology extraction should return relative sub-ontology that covers some sub-vocabulary. The efficiency of the existing ontology extraction algorithm is relatively low when they try to get a suitable ontology module from ontology at run time. This paper proposed a kind of ontology module extraction method. Related concepts and criterions of ontology modules extraction are studied; data structures and identification and evaluation methods of ontology module extraction are discussed; preliminary experimental results and the corresponding analysis are also shown.

The paper presents a new array of oscillating wave energy converter, which is in accordance with nowadays’ research tendency of China: high power, high efficiency, high reliability and low cost. The paper gives the design scheme and design parameters of the new wave energy converter. It's composed of the wave energy converter unit, which can be assembled to arrays based on demand. Besides, the paper analyzes the power generation principle and advantages of the device. The research results could be a reference for wave energy’s exploration and utilization.

Waste printed circuit boards is one of the main electronic waste,which has serious pollution,it has valuable metal and nometal.So its processing method is a very complex problem.There are a variety of recovery methods since the birth of waste printed circuit boards,and the most widely used method is mechanical method,which is practical and avoids the problem of environmental pollution.This article describes the recovery process of mechanical method of recycling waste printed circuit boards and the equipment used, and summarizes the status quo of mechanical method of recycling waste printed circuit boards in China and abroad.

These are many factors that can influence the properties of alkali-activated slag cementitious material, such as the modulus and content of water glass, water-cement ratio, curing conditions, and so forth. The rules that how these factors affect setting time and strength of the material are systematically discussed in the paper. It is found that the setting time of the material depends on the concentration of alkaline ions in solution; The material will have the best strength when the modulus and content of water glass are 1.4 and 8%, respectively. The curing temperature increase will be helpful to compressive strength increase.

In order to help teachers to identify plagiarism in student assignment submissions among students’ Source code quickly and accurately, this paper discusses a measurement method of Source code similarity. In the proposed algorithm, firstly, both of token oriented edit distance (TD) and token oriented length of longest common subsequence (TLCSLen) is calculated; secondly, considering the TD and TLCSLen, a similarity calculation formula is given to measure similarity of Source code; Thirdly, a dynamic and variable similarity threshold is set to determine whether there is plagiarism between Source codes, which ensure a relatively reasonable judgment of plagiarism. This method has been applied to the university's programming course work online submission system and online examination system. Practical application results show that this method can identify similar Source code timely, effectively and accurately.

Virtual Power Plant (VPP) is recognized as essential for the successful implementation of smart grids, and information communication technology is enabling technology for VPP implementation. However, finding the most appropriate technology that can satisfy their future communication needs is still an unsolving issue for VPP. Focusing on the hierarchial VPP control model, and utilizing Ethernet Passive Optical Network (EPON) network technology, this paper has presented an EPON-based communication architecture for virtual power plant.

Grid-enabled vehicles (GEVs) can draw and store energy from the power grid to support their propulsion systems as well as feed back power to the grid via power converters. They are regarded as one of the most effective tools to address environmental and energy issues. This paper provides an overview of wirless communication networks that support the GEVs application. More specifically, the operation modes of Grid-to-Vehicle and Vehicle-to-Grid are described, and representative wireless communication technologies which may be adopted for the premise networks and field area networks/neighborhood area networks (FAN/NAN) are discussed.

When confirming the partial factors in design formulas by the probability-based limit states design method (PLSDM), the structural coefficient can determined by two methods. On one hand, the structural coefficient is determined by the engineering experience calibration method, which is calculated by decomposition of the safety coefficient in the former specifications SD144-85. On the other hand, it can be determined by the probability analysis method and optimization calculation based on the target reliability index resulted from reliability calibration analysis. The appropriate value is finally determined by synthesizing results of the two methods.

The Smart Grid uses two-way flows of electricity and information to create a widely distributed automated energy delivery network, and Vehicle-to-Grid (V2G) and Virtual Power Plant (VPP) are two innovative smart grid applications. This survey focuses on V2G implementation through VPPs. First, the concept of V2G and its architectures are introduced. Then VPP, a new power plant concept and its corresponding control methods are described. Finally, implementation strategies of V2G through VPPs are categorized.

A method is presented for determining the pouring point location of concrete pump truck. The method does not change the structure of the concrete pump truck, only need to replace the hydraulic cylinders of booms with the hydraulic cylinders with displacement senor, and the displacement sensors are mounted in the inside of the hydraulic cylinders and do not need any extra protection. The relationship formulas between the contraction and expansion amounts of the hydraulic cylinders and the pouring point location are derived and programmed to input into a data processing unit. The contraction and expansion amounts of the hydraulic cylinders are timely acquired and inputted into the data processing unit, then the pouring point location can be displayed in real-time on the screen of radio controller, and the workers can quickly and accurately locate the pouring point of the concrete pump truck to poured point.

Direct Digital Synthesizer （DDS） is a new theory starting from the conceptual phase required for the direct synthesis of waveforms, This system in the FPGA chip and D/A conversion circuit, filter circuit, amplitude amplification circuit and power amplifier circuit's support to achieve a meet scheduled targets multiple waveform output.

With the substantial investment from government and enterprises, the community information system is playing a more and more important role in citizens’ life. It is therefore important to measure the usage intention of CIS system from the different perspectives. By using theory of planned behavior, this paper wants to derive useful variables to address the problem of the low usage intention of CIS by citizens. The primary purpose of this study was to examine beliefs contributing to the public’s intention behavior to use community information system in their daily life. The secondary purpose was to investigate the efficacy of the decomposition of planned behavior model for such behaviors.

Modeled on data quality evaluating methodology, a standardized real-time rule framework is proposed. The framework is accurate and reliable for estimating aerospace experiment tracking information. By converting all the rule evaluating results that consisted of time-delay, error, range and etc. to a uniform questionable data count format, the framework presents an algorithm that takes both tracking source and station into account based on questionable data statistics for quantified information quality evaluating. The quantitative quality evaluation of measurement information problem can be solved via the proposed framework.

Multi-frequency receivers rely on GNSS to achieve high-precision positioning, high sensitivity and other functions. GNSS signal frequencies are widely distributed around 1.1GHz to 1.6GHz. Good performance RF front-end receiver will provide high-quality acquisition and tracking environment, reducing the SER to ensure CNR. RF sampling technique is widely used in software radio for its simple structure, flexible configuration, and other advantages, but rarely used in satellite navigation, because the high signal carrier frequency and sampling rate, down-conversion based on RF sampling becomes a big challenge. So, to solve the problems of widely distributed we design three signal bands, using different local oscillator to implement signal down-conversion; to solve the problems of high sampling rate, we propose a down-conversion program of using a cascade of CIC filter’s ployphase and FIR compensation filter. Through the simulation of MATLAB after tracking tests, analysis of CNR and other indicators of programs. Ultimately, we implement the program with Verilog language on the multi-frequency GNSS receiver. The results show that this scheme can achieve digital down-conversion and stable performance of tracking loop with less consumption of resources.

Balancing with the influence coefficient method can eliminate rotor unbalance effectively and briefly which usually causes mechanical vibration. But the accuracy of this method is susceptible to operating condition and the structure of mechanical equipments will leads to unstable equilibrium outcomes. The theoretical study of the influence coefficient balancing method can find that the solution process of balancing weight does not involve the mechanical nature of unbalance vibration, and therefore it will be subject to greater interference of equation’s ill-conditioned characteristics. By introducing the modal superposition, vibration mode function can be linked with the influence coefficients to establish the relationship between counter weight location parameters and ill-conditioned equations. The simulation results of multiple-blade rotor shows that positions of balancing weight will exert great influence on ill-conditioned characteristics. So the position parameters should be chosen in front of balancing service reasonably.

Recently, with the rapid development of the Internet industry, wireless sensor network technology has received much attention of researchers both at home and abroad. Wireless sensor network node has become one of the basic researches of wireless sensor network. Because there are many problems to be solved, such as a balance of power, transmission efficiency, routing mechanism, cost control and node management, it also has always been the hot spot of the researchers. Wireless sensor network applications, such as navigation guides, object recognition, object positioning all require information service based on location, so wireless sensor network positioning technology is the precondition of the application implementation.

With the continuous expansion of the grid size, the number of checkpoints metering device is also increased workload and difficulty inspectors also increasing, to carry out verification and monitoring of remote metering devices mark significant. Discusses the remote calibration and monitoring system principle, function and application metering device at checkpoints, and also describes the configuration and functions of the system back-office support software, scientifically demonstrated the remote meter error, PT secondary circuit drop, CT and secondary circuit admittance verification and monitoring of significance.

The purpose of this research is to get the static mechanical distribution of the hybrid robot and provide the basis for its structural optimization. In this paper, the parallel manipulator which is suffered the maximum force of the robot is studied according to the statics analysis theory of space mechanism. The position distribution of extreme stress and extreme strain on the key components which is suffered the maximum driving force is obtained by the simulation of finite element analysis, then the strength of the existing structure is checked, laying the foundation for structural optimization.

On the basis of the characteristics of the shock pulse GPR echo signal and by using the principle of clock distribution control parallel data acquisition, we realize the high-speed data acquisition with low-speed parallel ADC device. The system consists of part of the signal input module, signal conditioning module, clock distribution module, data acquisition module and FPGA control module. The design with Simple circuit, level of clarity and good stability. It has practical significance and provides some reference to designers of other high-speed A/D conversion.

Bio-absorption has an unparalleled advantage over other traditional methods in removing and recycling heavy metal ions from waste water. Consequently, it has a promising future. In this paper, the traditional methods and the bio-sorption method via which heavy metals are removed from waste water are compared to summarize the mechanism of bio-sorption, the types of bio-sorbent, the factors that can influence bio-sorption and the state of its application in waste water treatment .

A vibration signal acquisition system was designed based virtual instrument technology. The process and principle design of structure vibration signal acquisition system based on LabVIEW software and CompactRIO hardware were discussed in detail. Finally, system test was conducted by a three story steel frame structure. And the test results were compared with traditional instruments system. The experiment showed that the data acquisition system of structure vibration signal which based on CompactRIO is precise and reliable in measurement results, and can realize multi channel synchronous data acquisition, storage, and support the real-time online data filtering and spectrum analysis and so on.Compared with the traditional platforms, the system proposed in the paper has short development cycle, low cost, user-defined functions, rugged, portable and other advantages. It can be widely used in complex and special building environment, so it will have a broad application prospect in the field of SHM.

Both of architecture and landscape are complexes of technology and art. Steel structure’s excellent mechanics performance and aesthetic characteristics make its application in modern architecture and landscape design increasingly. This paper analyses the intrinsic relevance of aesthetics and structure, and expound the application of steel structure on the aesthetic characteristics of architecture and landscape, also analyses related cases. The research results will provide reference for steel structure aesthetic characteristics analysis.

In dam seepage line monitoring process, dam saturation line "inverted siphon" phenomenon appeared. In order to study the time effect, indoor model test were done. The dam seepage line rules and conditions were determined. The results show that when the reservoir water level dips, the dam seepage line with the decreasing of the water level will drop. But the changing has lagged far behind. Hysteresis and permeability dam, seepage path length, the upstream water level and other factors related to the rate of decline.

To resolve the problem of no guidance about how to set the values of numerical meta-parameters and difficulty to achieve optimization of Deep Boltzmann Machines, genetic algorithms are used to develop an automatic optimizing method named GA-RBMs (Genetic Algorithm-Restricted Boltzmann Machines) for this model’s aided design. Based on the Restricted Boltzmann Machines’ features and evaluation function, a genetic algorithm is designed and realizes the global search of satisfied structure. We also initialize the network’s weights to determine the number of visible units and hidden units. The experiments were conducted on MNIST digits handwritten datasets. The results proved that this optimization reduced the dimension of visible units and improved the performance of feature extracted by Deep Boltzmann Machines. The network optimized has good generalization performance and meets the demand of Deep Boltzmann Machines’ aided design.

The local approximation method exhibits many advantage features and it is popular to a broad class of structural optimization problems. In this paper, both the mathematical modeling and case study of the local approximation method were studied. The theoretical analysis indicates that the primary optimization problem can be replaced with a sequence of explicit approximate problems by using the local approximation method. The explicit subproblems are convex and separable, which can be solved efficiently by using a dual method approach. The topology optimization of a guide rail design is then solved to testify the proposed method, which has been coded by Altair OptiStruct. The optimized design of a widely used guide rail with an “I” shape cross section is obtained and compared with the original design. The numerical results have shown that the local approximation method can effectively solve the structure optimization problems, especially the ones with hundreds of design variables or constraints.

Through the classical molecular dynamics, the melting properties of the the tungsten and aluminum mixed clusters are explored. By using simulated annealing the structure of the mixed cluster is obtained. It is found that the Al atoms tend to locate on the surface of the clusters. The melting behaviors of the clusters are analyzed in detail by the atom-resolved Lindemann index. The curves of Lindemann index show that the melting process of the can experience three steps which is not common in the melting process of the nanoclusters.

To achieve real-time monitoring for new type of robot motion state, the testing software of robot motion characteristics is studied in this article, based on Linux system, using Qt software compiling. First of all, the new robot prototype and test hardware system are introduced; secondly, the real-time testing curve of displacement, velocity and acceleration are compiled by fitting of the measured data, on the Linux operating system platform, using Qt programming; finally, the testing software run, and its accuracy is verified by experiment.

Road safety from various environmental disasters has gained much attention during construction project. Global warming has changed the weather patterns, such as regional torrential rains, heavy snow, and severe cold, and these irregular weather changes have brought huge amount of physical and human damages. In winter season, road freezing caused by snow or icing condition has increased the traffic accidents: traffic mortality is larger in winter than other seasons. In this paper, snow melting mechanism on road pavement by solar radiation and the effect of shadow and temperature is analyzed. Also, numerical analysis on snow melting is performed to provide the guideline of road design considering the solar radiation in an effort of mitigating the road freezing and reducing the traffic accidents in winter.

An ensemble consists of a set of independently trained classifiers whose predictions are combined when classifying novel instances. Previous research has shown that an ensemble as a whole is often more accurate than any of the single classifiers in the ensemble. Boosting-BAN classifier is considered stronger than Boosting-MultiTAN on noise-free data. However, there are strong empirical indications that Boosting-MultiTAN is much more robust than Boosting-BAN in noisy settings. For this reason, in this paper we built an ensemble using a voting methodology of Boosting-BAN and Boosting-MultiTAN ensembles with 10 sub-classifiers in each one. We performed a comparison with Boosting-BAN and Boosting-MultiTAN ensembles with 25 sub-classifiers on standard benchmark datasets and the proposed technique was the most accurate.

Surface and subsurface defects of optics are of major concern in improving laser induced damage threshold. SiO2single layers were fabricated by physical vapor deposition and sol-gel technique on fused silica substrates. HF acid etching and ultrasonic cleaning process are used to investigate the effect of surface and subsurface defects of substrates on the laser induced damage threshold (1-on-1, 8 ns at 355nm). Experimental data are then fitted with the Gaussian model of threshold distribution, which permits to discriminate different kinds of defects and extract their densities and threshold distribution. The interpretation of these data is further discussed according to their cleaning and fabrication method.

Different styles (invariable amplitude, sweep frequency, amplitude modulation) of continuous wave irradiation experiments are done on a certain radio fuze, and the failure regularity are summarized. The accidental explosion reasons are generally illuminated, and the failure mechanism under different irradiation conditions are particular analyzed. Finally, the failure regularity and mechanism of different irradiation conditions are compared. The results show that different electromagnetic environment will have different effects on the same fuze, and the failure regularity and mechanism are also different.

One of the function of digital painting images is to let the image simulation the painting style of artist,while to generate artistic image which has a vivid artistic effect.However,the manipulation process is complicated,cumbersome and means of a single. It can not let the non-professional personnel to master simply and easily. This article embarks from the common painting style technique and theory, using the photoshop, Illustrator CS4 software to process the paths,color gradation and the lightness, using the image color statistics and transformation simulation, and through the way of copying images to identify four different application techniques of painting style. Experiments prove that the methods and means can be simple, rapid, realistic to achieve the painting art effect.

Dissolved gas analysis (DGA) in oil is an important method for transformer fault diagnosis. This paper use random forest parallelization algorithm to analysis the dissolved gases in transformer oil. This method can achieve a fast parallel fault diagnosis for power equipment. Experimental results of the diagnosis of parallelization of random forest algorithm with DGA samples show that this algorithm not only can improve the accuracy of fault diagnosis, and more appropriate for dealing with huge amounts of data, but also can meet the smart grid requirements for fast fault diagnosis for power transformer. And this result also verifies the feasibility and effectiveness of the algorithm.

The fluctuation is an important factor that limits large-scale integration of wind power into power grid. In order to improve penetration level of wind power, the EVs based on V2G are considered to participate in regulating wind power while considering charge-discharge characteristics of EV battery. Thus, in this paper, an optimized EV charge-discharge control model is proposed to reduce output fluctuation of wind power. The Monte-Carlo method is used to simulate the stochastic wind speed based on Weibull probability density function. Finally, Genetic Algorithm (GA) is adopted to solve the problem. Results indicate that the EVs based on V2G can reduce the wind power fluctuation level to some extent, absorbing the wind power surplus and compensating the of wind power shortage.

Based on modal strain energy method, the paper discusses viscoelastic free layer damping sheet, establishes the finite element model of it and obtains the natural frequencies and loss factor. Then the paper calculates the loss factor of viscoelastic free layer damping structure with engineering empirical formula, and compares the result with that obtained by finite element method. By comparing the two results, it indicates that the finite element method is effective in analyzing this kind of problems.

Gear transmission is one of the most important mechanical transmissions. It is widely used because of its high efficiency, compact structure, stable transmission ratio, etc. In general, the failure of gear transmission is mainly due to the failure of tooth. Tooth broken main failure mode of gear tooth is mainly due to the role of the tooth root bending fatigue. So, researching both tooth root bending fatigue strength and tooth surface contact fatigue strength are of great significance for the guarantee of gear life. Basing on romax this paper chooses a gear-bearing-rotor system as the research background to conduct parameter sensitivity analysis of gear contact and simulate the changes of tooth root bending stress and contact lines position in the whole meshing process of gear pair.

Tolerance analysis plays an important role at the stage of product design and has great influences on the assembly quality and manufacturing costs. A positioning mechanism composed of two parts with cylindrical and planar junction is chosen for studying the influences of datum precedence on functional tolerance analysis. For different cases, the tolerance specification is specified with ISO tolerance language and the analysis line method is applied to obtain the analytical expression between the possible displacement on functional feature and geometric deviation on each part. The results for different datum precedence are summarized in this paper.

Referring to the requirements of national standards in residual voltage test of electrical products quality inspection, the methods, requirements and calibrations of residual voltage test were discussed. Mainly the problems of affecting accuracy at the time of the test voltage were analyzed, and the specific solutions were put forward.

The water immersion technique is conducted to increase the surface area of the triple base propellant. In order to investigate the influence of water erosion on triple base propellants, the SEM and material tester were used to observe the surface texture and test the mechanical property at different temperature .The result shows that the effect of water erosion on structure is superficial, the erosion depth is about 50~150 μm after 60 minutes,which does not impact the interior structure. The tests of mechanical property indicate that the mechanical property declines with the time of water erosion increasing, the decrease at room temperature is less than the decrease at high and low temperature.