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To verify and analyze the dynamics model of servomotor and improve the efficiency of modeling and analysis, we research system of modeling and simulation on kollmorgen AKM41H servomotor in SimScape. According to the driving principle and mathematical model of DC servomotor, Simulink combined with SimScape and Solidworks part will conduct Control system simulation and analysis. By analyzing the frequency curve, we know that dynamics model of Kollmorgen servomotor is accurate. Semi-physical simulation based on SimScape, the angle of motor shaft can be fast and accurate to get the prespecified value. Parameters of feedback control system are selected reasonably, adjust the motor shaft’s speed so that it reduces to zero band. Research shows that SimScape combined with Solidworks take semi-physical simulation experiment. It can support simulation that is different complex engineering project. Compared with the traditional simulation model is more practical and analysis and modeling is more efficiency.

In order to know the key factors of callus development on single cell clone, characteristics of physiology and biochemistry and morphological structure on two types of Alfalfa callus was studied. The results showed that the cell membrane permeability and malondialdehyde content was same on two types of callus; but, their soluble sugar content and peroxidase activity in cells was larger different, the soluble sugar content: soft callus > huge callus, and soft callus was 2.09 times of huge callus; peroxidase activity: huge callus > soft callus, and huge callus was 1.35 times of soft callus. Huge callus cells were larger, loosely arranged, cell vacuolization and cytoplasm was thinner than soft callus. However, soft callus cells were smaller, loosely arranged, cell vacuoles was smaller and cytoplasm was thicker than hug callus. Huge cells had the same membrane metabolic with soft cells, but soft cells had higher sugar accumulation than huge cells, and soft cells metabolism are vigorous, while huge cells are more aging.

Copy technique is one of the key technologies to ensure data safe and reliable on cloud storage. It is believed that research of copy technique plays an important role in the development and promotion of cloud storage. In this paper, the open source HDFS is used as a platform to analyze the features of copy management and the current problems on cloud storage. Considering the user variability on cloud storage, a dynamic copy redundancy strategy is given, which is based on file popularity. In this strategy, we calculate the current file popularity, which depends on different weights given by different access frequency

A method to analyze and detect the features of rotor and stator asymmetric faults for AC motor is put forward in this paper. After modeling the damaged asynchronous motor, stator’s three-phase current signals of the motor at normal status, as well as that with stator and rotor bar asymmetric faults, are simulated and analyzed qualitatively. In view of the shortcomings of Park’s vector transformation in the analyzing motor current signature, a method is put forward by combining it with signal amplitude demodulation. Based on this new method, the asymmetric features are expected to be extracted completely through the amplitude relative normalization and spectrum analysis. Finally, the availability of this method is verified by detecting and diagnosing the faults in actual AC motors.

With the rapid development of cloud computing, Security problems has become one of the major obstacle against it. In this paper, we present a hybrid encryption scheme based on the characteristics of RC5 and ECC encryption to deal with security issues caused by data residue in static storage and Save the storage space at the same time.

The manned spacecraft is a typically confined space in microgravity and it suffers severe fire risks. This paper studies on the distribution of the fire parameters in space-confined microgravity to find a more rational way to install the fire detectors. The experiments are carried out in the ground simulation experiment platform for fire based on the International Space Station. Based on the functional simulation principle, this paper maintainsGr(Grashof number) and increasesRe(Reynolds number) to simulate microgravity environment in such a full-scale platform. The results show that Fire Detector 5 on the center of the side wall and Fire Detector 7 on the corner of the ceiling are the best installing locations for smoke detection. And, temperature detection is not appropriate in manned spacecraft. Namely, the way to install the fire detectors in manned spacecraft should be different from that in normal gravity.

Data from sensor array are often arranged in three-dimension as sample × time × sensor. Traditional methods are mainly used for two-dimension data. When such methods are applied, some time-profile information will lost. To acquire the information of samples, sensors and times more exactly, parallel factor analysis (PARAFAC) is investigated to deal with three-way data array. Through the analysis and classification of three kinds of oil odor samples, the performance of PARAFAC in gas sensor array signal analysis is verified and validated.

Weather, industrial structure and power demand side management can affect the load, however, the power demand side management has the most direct influence on the change of load. This paper first introduces the purpose of the electric power demand side management, then it introduces the relationship between the load forecasting and the power demand side management, furthermore it respectively introduces a variety of load forecasting method according to the time distribution, finally it compares the advantages and disadvantages of load forecasting methods for each time distribution respectively, and this will provide a new basis for power grid planning.

The distributed computing framework of MapReduce has been widely used in big companies as a powerful tool for processing large scale of data. This paper will introduce the existing algorithms about MapReduce job scheduling and analyze the major two ones. It points out the defects of multi-task scheduling application on processing massive jobs and proposes a kind of multi-task cluster schedule algorithm MSBACO which is based on the ant colony optimization. The results of the experiments have proved its effectiveness and stability in heterogeneous environment.

Along with the expansion of power system, the rapid growth of load in power system and large capacity generators continuously going into operation, the increasing of short-circuit current level cause a serious threat to the security of the power system. The contradiction between high fault currents and limited circuit breaker interrupting capacity is prominent, in order to limit high short-circuit current, reduce the energy loss of traditional fault current limiter, and improve the limiting depth, this paper presents an new fault current limiter (FCL), and analysis its ability of limiting short current.

In order to meet new mode of operation in current Chinese electricity market, the paper puts forward the multi-objective optimization for plant-level load distribution based on economy and environment protection. It can balance the benefits between power plants and grids. While it can minimize coal consumption, reduce the emission of pollutants and make important effects on economy and environment. This paper proposes to calculate the sum cost of coal and sewage as the new model of objective function. Through the different weights on economy and environment, plants change the assigned load so as to make the objective function minimum and achieve the optimal load distribution. At the last we can get a optimal curve by simulation.

This paper mainly studies the generation mechanism of the power grid network loss and discusses Gauss - Seidel method, Newton-Raphson method,and PQ decomposition method of power network loss.

The new weapons and equipment of our military is endless, which is becoming more complicated and technical. And its updated speed is more quickly, price is more expensive, field equipment number is less and less. It is very important for the maintenance support of our armys equipment that Virtual reality technology is used in the army equipment for developing virtual maintenance training system. And it is important guarantee for cultivating qualified maintenance personnel. This article designs the simulation maintenance system to a certain type of equipment for the object based on VIRTOOLS. It provides effective solution for equipment maintenance. This paper studies and discusses the maintenance system structure system, the key technology and its realization methods.

A new self-expandable packer test-bed for performance testing is developed against many problems of self-expandable packer test-beds which are in existence during detection process, for instance, imitative open hole cannot be used to detect environments in the downhole, size of a specimen for detection is undersize, pressure in experiments is low and detailed data cannot be gathered in development phrase. The new test-bed makes autoclave a modular design, which can test various performance of a specimen in a high-pressure environment and match relevant replacement parts of autoclave with the purpose of doing a variety of experiments on specimens. In this way, many existing problems of test-bed during the experiments can be solved.

Fault indicator is widely used in distribution power network. Its number and installation location both affect the fault interruption time. This paper takes use of the immune algorithm to study the optimal installation number and installation location of fault indicator in distribution network so as to achieve the maximal benefit.

In the paper, we make a simple discussion to the heat meter verification process, this paper introduces the working principle of the infrared data communication, explains the advantages of using infrared communication, and explains the heat meter according to heat meter using infrared optical reading device data communication protocol the reading table data process, the analysis process in detail. Heat meter is expounded a good development trend of the application of infrared data communication.

This paper based on the idea of dynamic division of the load curve with the monotonicity of load curve and the PSO algorithm and gets the characteristics section. It fuses the sub-processes with the energy trajectory methods in order to describe the climbing peak and descending valley of the load curve closely, and characterizes the actual load curve. The multi-objective daily generation scheduling model is built based on the lowest cost of thermal power purchase of electricity and the lowest emissions of pollution gas. The optimal power flow based on combination of satisfaction degree and close degree are introduced to transform multi-objective into the single-objective optimization model. Decision makers can make interactive solution via adjusting goal satisfaction degree and close degree,so as to receive satisfactory results considering all aspects and make the daily generation scheduling based on energy-saving and environmental protection.

a new generation of single equipment and single network structure of intelligent substation is proposed in this paper on the basis of the current three layers two network smart substation, the key technology of this kind of new intelligent substation needs are also proposed in this paper, such as port mirroring, VLANs and IEEE1588. Examples of key technologies are presented,using industrial Ethernet switch, providing reference for engineering applications of new smart substation .

Mega-sub controlled structure (MSCS) is a new structural configuration presented recently and has received widespread attention . To further improve the structural control effectiveness of MSCS, in this paper, a new hybrid control method is proposed which employ active control and adjust the stiffness of substructure together to form a huge hybrid controlled system based on the particular conformation characteristic of MSCS. The control law and dynamic equation to assembling parameter matrixes for the MSCS subjected to horizontal seismic excitation are presented. The result indicates that, compared with the corresponding status without actuators, the new structure employing hybrid control method proposed in this paper has the ability to develop a high level of response control effectiveness when subjected to seismic excitations and does significantly further reduce the responses of structure; a much better control effectiveness will be obtained after parameters optimization.

This paper presents a new method to detect fire and alarm in confined space based on electronic nose. Common confined space includes some distribution cabinet, machine room, warehouse, air cargo compartment and spacecraft cabin, etc. Combined with the characteristics of the confined space, a fire detection and alarm system is schematically designed. This system is based on electronic nose and is an aspirated configuration. With this system, this method adopts PNN as the recognition algorithm, and introduces steady status and warning time to the monitoring host. The CO, O2, CO2and temperature are taken into account as the input of the PNN to get the probability of fire. Compared with the normal methods, this method can detect fire more quickly, reduce the false and missing alarm rate and realize real-time online alarming.

A numerical study based on VOF model has been carried out to investigate the dynamics of water droplet impact on solid surface in microgravity in comparison with that in normal gravity to discuss the differences of the extinguishing mechanism of water mist in different gravity level. Water droplets with different initial diameters and impact velocities were considered. The simulated results show that the deformation process in microgravity lags behind that in normal gravity. And it was also found that Dmaxand spread velocities are smaller in microgravity as the potential energy decreases and the time taken for a liquid droplet to reach its maximum spread has no obvious regularity. Hence, the effect of cooling the fuel surface and diluting fuel vapour with water mist in microgravity may be not as good as that in normal gravity.The critical impact Weber number for water droplet breaking up in microgravity is lower than that in normal gravity as the reduction of the value of Bond number, which may result in diluting fuel vapour with water mist in microgravity being more effective than that in normal gravity in some case.

Recycled aggregate performance vary with different native concrete strength and use environment. Recycled fine aggregate was obtained after the primary concrete was broken and screened. According to Recycled coarse aggregate for concrete and mortar (GB/T 25176-2010), the physical properties of the different types of recycled fine aggregate were analyzed, in addition, determine the classification. The results shows that the properties of recycled fine aggregate all meet the level and they are vary by strengths of its maternal primary concrete and using environments. The overall performance of fine aggregate of high strength primary concrete is the best, followed by the low strength concrete and the moderate strength concrete.

Endoscopic surgery is increasing for minimally invasive treatment in recent years.But the conventional two-dimensional endoscope technique cannot provide three-dimensional information for surgeon. Lacking depth and other 3D information often made doctorshave to carry out the surgery depending heavily clinical experience.In response to the above described issues,this paper proposed a method based on improved SIFT algorithmto recover 3D structure information of the endoscopic environment, with the help of an optical tracking system which can provide the orientation of the camera in real time. The proposed approach is evaluated on sequence digital images gotten from an 1394 camera and the experimental results show that the proposed approach iseffective.

Automatic equipmenttransportation in the wild complex terrain circumstances is very important in rescue or military. In this paper, an accompanying system based on the identification and tracking of infrared LEDmarkers is proposed. This system avoidsthe defect that visible-light identification method has. In addition, this paper presents a Kalman filter to predict where infraredmarkers may appear in the nextframe imageto reduce the searchingarea of infrared markers, which remarkablyimproves the identificationspeed of infrared markers. The experimental results show that the algorithm proposed in this paper is effective and feasible.

Dynamic fracture of explosion containment vessels subjected to internal blast loads is the foundation for conducting safety assessment and failure analysis of explosion containment vessels. The experiments were carried out to investigate dynamic fracture characteristics of cylindrical steel shells subjected to internal blast loadings at the centers. The elastic-plastic response of cylindrical steel shells was conducted using nonlinear dynamic finite element analysis code LS-DYNA. The fracture mode and fracture mechanism of a cylindrical shell were specially studied through analysis of deformation， macrographs of fracture surface and elastic-plastic response. The results show that dynamical ductility deformations appear and the shear bands form when the cylindrical steel shell expands under internal blast loading. The cylindrical steel shell fractures preferentially along the shear bands due to its softening effect. The fracture mechanism is that the shear bands tear under tensile circumferential stress. The shear bands and the tensile circumferential stress dominate the final fracture mode. The fracture mode is of the ductile fracture.

Broken rules of cylindrical steel shell subjected to internal blast loads is the foundation for conducting safety assessment and failure analysis of explosion containment vessels. The experiments were carried out broken rules of the cylindrical steel shells subjected to internal blast loadings at the centers. The elastic-plastic response of cylindrical steel shells was conducted using nonlinear dynamic finite element analysis code LS-DYNA. The results show that the deformation was’t a discrepancy in the explosion center of the cylindrical steel shell in same space, and the deformation descended slower along with thickness augmentation in the end of explosion center. The radial stress、hoop stress and axial stress was a discrepancy in the thickness way of cylindrical steel shell of explosion center The most leading cause of destructivity of cylindrical steel shell was that inner wall bearing normal stress and exterior wall bearing tensile stress; the hoop stress was broken more than axial stress cylindrical steel shell. The whole process was presenting hoop fractured and axial growth.

To input rational customer requirements into engineering design process more effectively and improve product design quality and market response efficiency, this paper focuses on the interaction between market analysis and engineering design decision for the modular product. While many researchers have successful evaluated and optimized the design schemes, few, if any, have provided a bridge the customer selection and firms product development decision. After a review of the literature we introduce the flow of user-engineering design interaction including both maximize the utility of customer and the profit of the firm. On the user and market analysis flow, customer requirements are defined according to the target market, then the customer selection possibility link to the product attributes by utility function. Accordingly, the alternatives are corresponding to the module different product, and then using decision support problem method to search the optimal design parameters. Two design domains can share the design information and realize the cooperative design process by computer computing platform.

The green supply chain management, as a new model of modern management, aims to achieve the goal of the sustainable development of social economy and promote the core competitiveness of enterprises. This paper shall begin with the connotation of supply chain management, then the ways to implement green supply chain management shall be elaborated respectively: promoting environmental legislation, developing cluster supply chain network and eco-industrial park, establishing platform of network information system, cultivating market environment of green consumption, changing environmental conception and cultivating green enterprise culture, re-engineering business process and encouraging green technological innovation, establishing strategic cooperation and constructing performance of evaluation system and generally participating in and inspiring green supply chain management.

According to the fire burning features, this paper proposes a low-power fire detection algorithm under complex background. In this algorithm, adaptive statistical background features are used as the basis for background suppression to remove the background image effectively and local accumulation area method is used to eliminate interference and identify areas of fire flames. The algorithm solves a difficult problem that low-power fire detection in video sequences which exists in complex background and low SNR is difficult to get. The experimentation results show that under the condition that the image resolution is 400 × 300, the algorithm proposed in this paper can identify the flame within 100 pixels with algorithm response time less than 7s, recognition rate more than 90% and false positive rate less than 10%.

Aiming at the filature of titanium plates and screws after defective mandible reconstruction surgery, a method named Finite Element Analysis （FEA）was conducted in this paper through FEA software Abaqus with which a 3D model of defective mandible was established. The mandible 3D model was input into the Magics and remeshed. The mandible model was output in the format of .inp file from the Magics and import to Abaqus for converting from triangular meshes to tetrahedral meshes. The tetrahedral meshes totally had 71057 tetrahedral elements and 10720 nodes. The boundary constraints of the mandible 3D model were arranged. The force was applied separately in the direction of vertical, 15° and 30° with the occluding plane (teeth force range when occluding) to analyze the force. The mandible 3D model was established and prepared to be done a biomechanical analysis.

Aiming at a clinical case of a 52-year-old male patient, the patient’s mandible will be 3 Dimensional (3D) reconstructed and the surgery will be planed. This patient who suffered from mandibular tumor needed to undergo surgery. This study used a Toshiba 64-row Spiral CT to scan patient’s maxilla and mandible. 368 layers consecutive maxillary and mandibular CT images which scanning slice thickness is 1mm were obtained. The original images which format were DICOM were import to Mimics. After decided the bone threshold value the contour lines of every layers were extracted. Every image was passed the processing steps of edge division, selective editing, filling holes, wiping off redundant data and 3D reconstruction. After these steps the 3D geometric model of maxilla and mandible was obtained. The dimension of mandibular tumor and accurate location of the removal part were determined. These steps provide accurate original data for the manufacture of mandibular Rapid Prototyping (RP) model.