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For the interference fit joint of massive flywheel assembly, Studies the reasonable amount of interference and its heating temperature options. Analysis the advantages and disadvantages of various assembly way, reasonable assembly method is proposed, Designed the corresponding assembly tooling , Use the cone positioning and the method of hydraulic push to ensure the higher precision alignment, Provides a reasonable reference for interference fit joint method for the flywheel .

JiTT (Just-in-Time Teaching) is a teaching method which emerged at the end of 20thcentury in America, whose core is “web-based active and interactive learning”. By introducing the essential features and the theoretical basis, this article emphasizes on the application of JiTT in English reading class. Three steps of JiTT are presented in this article.

To guarantee the QoS of the various traffics and take good advantage of the network resource, the QoS routing protocol based on resource optimization is proposed. By the network state information dynamic update and the QoS routing optimization model design, the QoS routing protocol can provide the optimal path for real-time traffic, broadband traffic and best effort traffic in time with low control message cost. Simulation shown that, compared to the traditional shortest path routing, the QoS routing can satisfy the demand of traffics and can improve the network performance.

In allusion to the grid structure and operation characteristics of the microgrid, in this paper a static voltage stability index for microgrid was deduced based on the existence of the power flow. The index has taken the node voltage into account and is free from the influence of the grids R/X; besides, it has a smaller error for it has no network loss equivalent during its deduction. Then one 13-node microgrid system was established to validate the deduced index, finally the index was used to analyze the influence of distributed sources including the PV, PI, P-Q(V) node types as well as heir locations and capacities on the static voltage stability of microgrid.

Using the analytical and numerical approaches, the nonlinear dynamic behaviors in the vicinity of a compound critical point are studied for a rectangular symmetric cross-ply laminated composite plate with a parametric excitation. The geometric nonlinearity and nonlinear damping are included in the governing equations of motion in this model. Normal form theory, bifurcation and stability theory are used to find closed form solutions for equilibria and periodic motions. Stability conditions of these solutions are obtained explicitly and critical boundaries along which incipient and secondary leading to 2-D tori are also derived. Finally, numerical results are presented to confirm these analytical predictions.

Electrochemical micro machining is a critical micro machining technology. The purpose of this paper is to study the effect of ethylenediaminetetraacetic acid (EDTA) complex electrolyte in electrochemical micro machining (ECM) of stainless steel. The micro machining of stainless steel is difficult by electrochemical machining, especially in machining deep micro holes, because of an oxide layer formed on the surface. In this paper, ECM of stainless steel in EDTA complex electrolyte was researched. The influence of electrochemical machining parameters such as pulse duration, electrolyte composition to machine stainless steel was investigated. The results showed that EDTA can enhance the stability of electrochemical machining and the electrolyte is eco-friendly.

To investigate the effects of the metallurgical route on the defects in mc-Si, various metallurgical routes were conducted. Dislocation formation and the resistivity of the mc-Si were also studied. The results showed that high inhomogeneity in dislocation distribution within individual grains and paralleled tacking faults could be observed when the ingot was grown by using the feedstock prepared by adopting the sequence of slag treatment, acid leaching and vacuum refining. Different grains have various dislocation density, which was showed in ingot grown by utilizing the feedstock prepared by adopting the sequence of vacuum refining, slag treatment and acid leaching, tacking faults could also be seen, as well as some dislocation clusters. The resistivity of this two ingots was detected at various height by using the a 4-point probe silicon tester, it was expected that the resistivity of these two ingots has the same tendency of the change, and the value of the resistivity of the ingot obtained using the previous technology was relatively higher than that of the ingot obtained using the latter technology.

The proportional modification parameters are useful for compensating the tooth form errors of spiral bevel gears. Based on the mathematical model for calculating the machine setting parameters and according to the relative position relationship between cutter and workpiece, the formulae for calculating the second-order proportional modification parameters for gears manufactured by spread blade method was deduced by the curvature and normal vector at calculation point. The proportional modification parameters can make the lengthwise curvature or profile curvature or lengthwise twist curvature of the concave and convex flank produce uniform change or difference change. The formulae is verified by experiment on CNC spiral bevel gear grinding machine and M&M sigma 7 gear measuring center.

The passengers' luggage checking not noly often make the airport staff embarrassed, but also not easy to locate accurately, which often affects passenger evacuation and causes unnecessary disputes. Most of the airport use fixed manual sorting or the technology of barcode, using these methods, however, which greatly affect the quality of services at the airport. This paper presents a system based on radio frequency identification technology (RFID) to achieve luggage matching automatically. In the system,RFID luggage tags will be attached to the target luggage, and the RFID tags which match with the target luggage will be built into a special boarding cards. Only the two RFID tags matching, passengers can freely leave the door in the exit. In order to solve the problem of overcrowding in the luggage claim, this paper proposes to install the LED prompt lights and luggage tracking devices in the U-shaped turntable to improve the accuracy of the luggage claiming. The system provides a new method for airport luggage positioning and management, which be proved of high efficiency, low error rate with some advanced and practical.

Aircraft in flight, such as supercooled water droplets encountered icing conditions suitable for the external environment, the relevant parts of the body will freeze, making the aircraft's aerodynamic performance deterioration, severe endanger flight safety, in addition, the aircraft parked in the open winter months , there will be icing, you need to clean up before takeoff. We should grasp the mechanism of aircraft icing, environmental factors and easy to freeze parts of the body. This paper presents a simulation using the wind tunnel icing device icing wind tunnel simulations can reproduce the real situation of aircraft icing, for guiding practice and got good results.

Aircraft in flight, such as supercooled water droplets encountered icing conditions suitable for the external environment, the relevant parts of the body will freeze, making the aircraft's aerodynamic performance deterioration, severe endanger flight safety, in addition, the aircraft parked in the open winter months , there will be icing, you need to clean up before takeoff. We should grasp the mechanism of aircraft icing, environmental factors and easy to freeze parts of the body. This paper presents a simulation using the wind tunnel icing device icing wind tunnel simulations can reproduce the real situation of aircraft icing, for guiding practice and got good results.

Helicopter lift system aerodynamic design is the key to success helicopter design technology. Currently helicopter lift system has complex structure, fuel consumption, low efficiency and many other issues, which greatly limits its potential to play, so the research of new efficient, simple and practical helicopter lift system is imminent. In this paper, a new kind of helicopter-lift device, combined with the whole structure, the specific presentation of the entire lift device works and ways of working. Based on 2D N-S equations and Spalart-Allmaras turbulence model, the device numerical simulation of two-dimensional aerodynamic characteristics. The results showed that: The lift device is feasible, can be applied to the helicopter technology. The results can lift device is designed for the helicopter to provide certain technical reference.

In ship pitch balance system, serious flow impact and water hammer occur because of the turning on and off of valve during the procedure of water-shift. Flow area of the ball valve used most on ship was derived, and mathematical models of pressure lost before and after valve were formulated. Besides, considering the fact of water-shift balance system, an AMESim model was established based on improved traditional throttle model. And the validity of AMESim model was ascertained by comparing simulation results of stable pressure before and after valve with calculated values from mathematical models. Then, with the AMESim model, impact characteristics of water-shift pipeline were investigated when adopting various valve switch rules, length of pipelines before and after valve and using an accumulator in system. From that, methods to reduce pipeline impact were proposed, which make good references for noise control of ship pitch balance system.

The building energy consumption is one of three in China's energy consumption, the detection and monitoring for energy consumption of building is the basis for the work of building energy efficiency. This article describes a perception, monitoring and management system of building energy consumption based on Internet of Things technology architecture, in the system, various energy instrumentation is installed inside the building and measurement all kinds of energy consumption data in the perception layer, collection daterminal data connected to the RS485 bus access gateway for data transmission via Ethernet or mobile communication network in the network layer and transport layer, deal with the statistical analysis of the energy consumption data in the application layer. The system has been successfully applied to more than 50 large-scale public building to implement energy consumption monitoring and management, and the support of the underlying data for building energy efficiency.

Using the analytical and numerical approaches, the nonlinear dynamic behaviors in the vicinity of a compound critical point are studied for a simply supported functionally graded materials (FGMs) rectangular plate. Normal form theory, bifurcation and stability theory are used to find closed form solutions for equilibria and periodic motions. Stability conditions of these solutions are obtained explicitly and critical boundaries are also derived. Finally, numerical results are presented to confirm the analytical predictions

According to the characteristics of AVS video data, a RTP encapsulation method based on frame type is proposed. When the video data is encapsulated by the RTP protocol, different types of video data such as sequence header, sequence end, I frame, P frame and B frame are encapsulated with different method. Under the limit of maximum transmission unit (MTU), sequence headers, sequence ends and I frames are encapsulated individually to reduce the packet length and protect the important data. While multiple P frames and B frames are encapsulated into one RTP packet to reduce the quantity of the RTP packets and decrease the overload of link. Simulation results show that, compared to the frame-based encapsulation method, the proposed method can reduce the packet loss rate of the video data effectively and improve the quality of video service.

The proportional modification parameters are useful for compensating the tooth form errors of spiral bevel gears. Based on the mathematical model for calculating the machine setting parameters and according to the relative position relationship between cutter and workpiece, the formulae for calculating the second-order proportional modification parameters for gears manufactured by spread blade method was deduced by the curvature and normal vector at calculation point. The proportional modification parameters can make the lengthwise curvature or profile curvature or lengthwise twist curvature of the concave and convex flank produce uniform change or difference change. The formulae is verified by experiment on CNC spiral bevel gear grinding machine and M&M sigma 7 gear measuring center.

The emergence of wireless packet-switched networks such as Universal Mobile Telecommunications System (UMTS), and wireless local area networks (WLANs) can provide voice, data, and video services for users. In this paper, we propose a network selection scheme in the wireless heterogeneous networks based on the traffic differentiation, conversational class, interactive class, streaming class, and background class. Simulation results demonstrate that the proposed network scheme can decide the optimal network to handoff according to the traffic class.

The aim of this study is to get a better understanding of Micro Flat-Wire Roll Forming Technology. There are three methods for Mirco flat-wire forming, i.e., drawing, extrusion, and rolling. Without replacing the equipment, rolling method only demands to adjust the relative roll gap between the pressure and the wire deformation that it can produce different specifications of mirco flat-wire. The rolling equipment was introduced and can be divided into three parts, the mechanism section, the control part and the wire-locating device. Furthermore, the rolling process parameters were summarized as well. The effect of rolling amount and rolling speed on the wire surface quality was also discussed.