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Multiple-scale community of complex networks has attracted much attention. For the problem, previous methods can not investigate multiple-scale property of community. To address this, we propose a novel algorithm (h_LPA) to detect multiple-scale structure of community. The algorithm is a heuristic label propagation algorithm associated with spectral analysis of complex networks. Label updating strategy of h_LPA is combined with heuristic function from the perspective of networks dynamics. The heuristic function further improves the dynamic efficiency of h_LPA. Extensive tests on artificial networks and real world networks give excellent results.

In view of the current situation of being unable to simulate repair time in virtual maintenance simulation, decomposing the repair process to repair therblig layer, and the new concept of repair therblig standard time is introduced, then developing the repair therblig time auxiliary system used for Jack, which realizes the statistical product repair time in virtual environment. This method provides significant reference value for paralleling maintainability quantitative parameters verification in product development stage.

To analyze the machining performance of grinding machine and improve the quality of tooth surface, this paper proposes an integrated model of processing performance evaluation of computer numerical control gear grinding machine. Based on the gear profile grinding machine kinematics principles, the topology modification formulas of tooth surface were deduced. Calculated the process capability index according to experimental data and found that the tooth surface errors were followed normal distribution. The main reason of formation errors was analyzed by cause and effect diagram. Finally, the validity of this integrated model of processing performance evaluation is numerically demonstrated using CNC gear grinding machine.

In order to identify new words in huge Chinese corpus efficiently, this paper comes up with an algorithm based on ensemble methods. At first we perform Chinese word segmenting with Trie and build segment-tree. Then we select words pattern drawing method, frequency filtering, independent word probability and naive Bayes model to be sub-models of ensemble methods and train them independently. At last we integrate results from different sub-models with a multi-layer model. In experiment, this algorithm is proved to be quite fast as well as product precise and high-coverage results.

A new type of tidal unit-vertical shaft tubular turbine is designed with high efficiency, large flow rate and low water head ,which has large power under the 2~3 meters water head. According to the data of the being installed tidal units and principles of tubular turbine’s design, the high efficiency vertical shaft tubular turbine was designed under large discharge and low head, which was suitable for the tidal power station. The design also considered the requirements of turbine’s size and the details of flow through the whole flow passage were attained. The turbine’s property was predicted by the 3-d numerical simulation software on the whole flow passage. Moreover, the influences of vertical shaft’s sizes were analyzed. And the terminal of vertical shaft with or without transverse brace and longitudinal brace were analyzed to get the influence. Considering the hydraulic performance of various methods, the best guide vane opening was chosen. The results show that, the turbine unit has the best performance on efficiency, hydraulic loss, etc. with the guide vane opening 62°, meeting the power station’s design requirements. The results show that the optimal designed flow passage’s efficiency reaches up to 88.4%, the flow rate becomes much larger and the power reaches 174.63kW. Without partial vortex, the flow pattern is smooth through the whole passage also with lower hydraulic loss.

Set the alarm value in the condition monitoring system of hydropower unit to monitor unit state parameters, if the difference between the two values exceeds the safety threshold, the alarm works, it is an effective method. Now the state parameters alarm values are set up mainly for the stable operation area in the unit condition monitoring system, which were not suit for low load conditions and in the process of load. To realize the full condition dynamic alarm of hydroelectric generating units, they are two ways: (1), build unit state parameter prediction model, compared predict values with the measured values. (2), set the alarm line, when the measured value exceeds the alarm line, the alarm works,. These two methods are considered the working condition head and output .This paper introduces several different alarm line settings, such as line alarm, partition line alarm, dynamic alarm curve and dynamic alarm surface.

In order to effectively extract nonstationary and nonlinear fault signature of hydropower units’ signals, a new method, based on Hilbert–Huang transform (HHT), is proposed. This method is used to carry out EMD (Empirical Mode Decomposition) analysis and Hilbert transform of signals firstly and then extract Hilbert spectrum to provide a basis for signal feature extraction. The vibration signal of upper brackets in hydropower units has been put forward with experimental analysis. The results suggest that the EMD can decompose vibration components in different frequency domain, which has intuitive physical meaning. Moreover, Hilbert spectrum also has a good resolution in time domain and frequency domain. Thus, HHT can be used to depict the fault signals effectively and lay the foundation of the fault pattern recognition.

Water hydraulic components have been developed rapidly in recent years. However many problems such as low lubricity and leakage limited the performance of them, especially water proportional valves. A proportional valve- hydraulic cylinder system with tap water as working medium is chosen as object to investigate the performance of water hydraulic system. With regarding to the weaknesses of the selected 4/3 proportional valve including lag, dead zone and nonlinearity, an integral separation PI arithmetic based close-loop controller is developed. Experiments results verified the electro-hydraulic proportional system of fast response speed and high accuracy.

The digital imaging technology based on underwater laser line-scanning is one of the developing and effective technologies for underwater electro-optical imaging. According to the requirements of ocean salvages, rescues and marine resources explorations, the technical features of the digital imaging system are analyzed comprehensively, the structural characteristics are discussed and the hardware components are introduced. The design gives the supports to develop the digital imaging system using underwater laser line-scanning technology and has great significance for application.

Sensorless control system for Permanent magnet synchronous motor (PMSM) has been widely used in many areas for its simple installing and easy realizing advantages. This paper mainly analysis sensorless control system of PMSM, estimate the angel of rotor and speed based on flux observation initially, PLL and state observer were used to obtain the accurate angle. Use Simulation toolbox design of MATLAB to implement the simulation of control system and analyze the simulation results. The results verify the correctness and feasibility flux observation method that used in paper.

Viscose fibers (VF) are widely used because of its good bio-compatibility and the adsorbent performance. In this paper, adsorbent fibers were obtained via wet spinning method with the mixed solution of activated carbon dispersion and viscose. The characterization of activated carbon/viscose fibers (ACVF) were evaluated by infrared spectroscopy (IR) scanning electron microscope (SEM) and Thermo gravimetric (TG). The results showed that activated carbon had already doped to the viscose. Benzene adsorbent performance research indicates that the adsorbent capacity of ACVFis better than VF.

Equipment retirement is one of critical links in for total life management, and is an important content. There are urgent problems that should be settled, how in the limited time to broaden the disposal channels and methods of retired equipment, dispose well the centrally retired equipment, fully act as value, and come true the best comprehensive benefits of politics, military affairs and economy. In the paper, with the rules of scientificalness, integrity, operability, qualitative and quantitative, it evaluates relative the ratio of effective and cost in accordance with the theory of value engineering, constructs the evaluation model of equipment retirement disposal benefits based on the Forced Decision Method of value engineering theory, sequences the disposal concept by calculating the value coefficients of every concept, thus it makes for producing the diversified scientific disposal management system of retired equipment, plays fully the value of retired equipment, and comes true the best comprehensive benefits of politics, military affairs and economy.

Experiments have shown that initial voids may exist in the manufacturing processes of pure aluminum, which adversely affect its mechanical properties. In this study, the process of plastic deformation around voids in pure aluminum was examined at atomic scale through molecular dynamics (MD) simulation. The Modified Embedded Atom Method (MEAM) was employed to characterize the atomic interactions in the pure aluminum with two voids. The calculation results revealed that the interaction of two voids endures three phases when the interval of the voids is increased: void coalescence, void coactions followed by the formation of a stress shield zone, and interaction vanishing. The critical parameters of the interval for the three phases were defined as well in this work. It was observed that crack initiated and further propagated near the voids along the slip systems of FCC crystal, which eventually caused structural failure. Meanwhile, the evolution of micro structure in the crack propagation process was investigated by means of Common Neighbor Analysis (CNA). The results showed that the phase transformation occurred near the voids during loading process.

A pairwise key pre-distribution scheme based on OKS and grids for wireless sensor networks is proposed. This strategy divides the sensor area into square cells and logical groups and distributes key information by employing the OKS scheme. This scheme effectively reduces storage cost, saves battery energy, has good network connectivity, and provides flexible security grades.

In economic development, resource has become increasingly important and the problem of how to allocate resource reasonably has become a hot issue..This paper proposes a new resource allocation mode based on DEA models taking into account production efficiency, input-output elasticity, potential production capacity. We put forwards a new weighted cross-efficiency calculation formula and a new resource allocation weights calculation formula. From the numerical example, the result is satisfactory.

For a long time, settings complexity makes the settings remote modification technology is difficult to be applied on the relay protective devices effectively. To solve the key technical problems of relay protective devices settings remote modification, this paper makes an in-depth research of setting group remote control model. The setting group remote control model based on protective relaying and fault information system is proposed with the setting group services mapping between IEC61850 and IEC60870-5-103. The setting group remote control models working mechanism is deeply analysed via the setting group views. Base on the analysis, an enhanced control flow and task block method are provided to avoid the edit setting group data being changed abnormally, which improves the reliability of setting group remote control remarkably. The setting group remote control model introduced in this paper is applied successfully and its reliability is approved.

This paper mainly studies the change rules of interior ballistic performance under different loaded conditions, especially the maximum pressure and the muzzle velocity. There are six parameters affect the performance. The results show that, changing one of the all parameters, the maximum pressure and velocity will be increased with the increase of propellant shape coefficient χ; increased with the charge increases; increased as the propellant force increases; decreased with the chamber volume becoming bigger; increased with the engraving pressure increases; the maximum pressure increases while the velocity decreases with the mass of the projectile increases. In order to improve the interior ballistic performance, these loaded conditions must be paid attention.

In order to assemble and layout of various irregular stamping parts, the paper proposed a new kind of algorithm combining CHNN and genetic algorithm. It built models for irregular parts, and these irregular parts were processed by using the surrounding rectangle methods and graphic composition. The paper used AutoCAD as a develop studio, and discussed CHNN and its mapping to layout and optimize the weight of CHNN by genetic algorithm. The core program adopted VB program language and developed the intelligent layout system. Sample analysis shows the results that the system has good man-machine interfaces, interactive features, high speed and quality retention of solution.

One type of spatial new parallel mechanism with two degree of freedom is proposed.. The position and velocity analytic equation are constructed based on the coordinate transformations. Finally, the singular configuration of the tilter is analyzed by the forward and the inverse Jacobian matrix.

By means of self-organizing clustering, a new color-based image retrieval method is proposed in the paper. According to the colors’ distributing information in the image, every pixel is assigned a weighing value and thus the initial number of clustering can be confirmed. Therefore, those weighed pixels are clustered and the dominant colors’ statistical features are acquired. Based on the dominant colors spread in the image, the colors’ moment features are extracted to present their spatial features simultaneously. Therefore, the whole image’s content can be expressed from general statistic to partial distributing by the two kinds of features. The experiments verify the method mentioned above more efficiently than those ways based on color histogram

This paper proposed a type of new parallel tilter with four degrees-of-freedom, whose moving platform has three rotations and one translation. The coordinate transformation is adopted to establish the position and velocity kinematics equation of the tilter. Simulation result indicated that the moving platform can move according to the set law by modifying the displacement of the piston rod in active limb.

Superparamagnetic iron oxide (SPIO) nanoparticles were used more and more universally in biomedical research recently. In order to develop a suitable immuno-magnetic probe which can be applied in antigen-antibody based immunoassay, such as tumor marker or cardiovascular marker detection, SPIO capped by dextran was synthesized with chemical coprecipitation method. With sodium periodate method, hydroxyl groups of dextran were oxidated to aldehyde groups, thus conjugated with antibodies by covalent bonds. Western blot pattern illustrated that structure integrity of the most antibodies was kept well, harmful influence given by oxidation of conjugation was very finite. Both immune reactivity and antigenicity of antibodies in the SPIO based immunoprobes were retained effectively. This probe has a potentially application in SPIO based novel suspension array for its superparamagnetic property that can be separated under gradient magnetic field.

The machining characteristics of SiC/Al composite using wire electro discharge machining (WEDM) were investigated in this study. Material cutting speed and surface roughness value were adopted to evaluate the machinability. Peak current, pulse on time, pulse duration and working voltage were selected as the input variables to investigate the machining performance. Effects of input variables on the cutting speed and surface roughness were experimentally tested. Peak current, pulse on time and working voltage were confirmed to have positive effects on cutting speed and surface roughness value. Whereas the cutting speed and surface roughness value decrease with the increase of pulse duration.

A new SLAM measurement model based on omni-directional vision and odometer is proposed in this paper. A virtual stereo vision composed of an omni-directional vision sensor and an odometer. Scale Invariant Feature Transform is used to extract stable and available vision features from the omni-images. The 3-D locations of these features are initialized by the pixel coordinates and the odometer data by stereo projection, and the locations will be corrected during the SLAM process when they are observed again. It is demonstrated that the new model can make a good accuracy with FastSLAM algorithm, and the accuracy is greatly improved corresponding to the classical vision sensor.

The combination of metal cutting theory, computer technology and expert knowledge was used to study the use of knowledge-based engineering (KBE) for cutting large containers. This report includes information on the acquirement, expression, and inference and management of KBE. The structure of the KBE system was established by selecting the principles of processing parameters and optimizing the model of machining data and by using the method of expressing knowledge of combining producing type with frame type and by using the software SQL server 2000. The inferential mechanism of every functional module in the system was realized by applying the software, VC++ 6.0. The KBE technology will help technicians to share expert knowledge and experience, and to optimize cutting parameters to intellectualize cutting design and machining.