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In this work, supersonic biplanes of the Busemann concept have been analysed, focusing on the unsteady aerodynamic characteristic due to flow disturbance using Computational Fluid Dynamics (CFD) codes in viscous flow. Flow disturbance is modelled by sinusoidal pitch motion simulated by mesh morphing using radial basis functions (RBF) method. The results suggest that there are two flow patterns of the Busemann biplane: oblique wave sequences flow (Pattern A) and choke-flow (Pattern B) with higher wave drag. Unsteady aerodynamic disturbance represented by pitch motion may cause flow pattern transformation. We have also obtained that Pattern B is more stable than Pattern A and choke-flow cannot be eliminated even after returning to the initial flight attitude. Moreover, amplitudes and frequencies of sinusoidal pitch motion play important roles in flow pattern transformation and there exist critical amplitudes and frequencies.

For the non-stationary vibration signals of wind tower, using a new method based on KPCA to eliminate the interference of the vibration signal. After cancellation noise according to the method based on EMD, the vibration signals are decomposed and the vibration characteristics of the signals are finally extracted. The experimental analysis indicates that this method can provide an effective reference for the health detection of wind tower.

270V high voltage DC power supply system with grid of light weight, uninterrupted power supply and a two power density higher characteristic, in recent years become a hot research topic in domestic and international air supply system.[ To ensure the high voltage DC bus power quality, for the safe operation of the aircraft is very important. Single phase aeronautical static inverter as a typical aircraft power system load, the input current ripple of the serious pollution of the high voltage DC power supply. Therefore, the harmonic pollution problem of how to control the high voltage DC power supply system has been increasingly concerned aviation power researchers.

In this paper, a design scheme is proposed of security network card based on AM 1808 for an embedded system. In the card, embedded firewall, network security device, hard-disk protection and restoration, encryption machine and other network security products are integrated. According to practical needs, the function of embedded security network card is extended and reduced.

Solar energy is the inexhaustible,enewable Energy. The solar cell is the solar light energy into electricity. The unique advantages of solar cell. Potential, more than wind, hydro, geothermal energy, nuclear energy and other resources, is expected to become the main pillar of power supply in the future. This paper studies that the main parameters of monocrystalline crystal silicon solar battery: the junction depth and superficial concentrations influence on electrical characteristics of monocrystalline silicon solar battery. The result shows that for maximum efficiency, it is bound to get the largest possible open circuit voltage, short circuit current and fill factor of the product, therefore, it is necessary to control these two parameters, the junction depth and doping parameters. If the junction depth is constant, with the increased superficial doping concentration of monocrystalline silicon solar battery, the photoelectric conversion efficiency of the battery increases slowly at first and then rapidly decreases, and the deeper the junction depth is, the more obvious trend of the photoelectric conversion efficiency is.

The networks of interdependencies in large-scale Object Oriented software systems are complex, visualization and understand become the important issues for developer. We propose that topology structure can be imaged to network and better understood via core structure decomposition based on complex networks. The core structure analysis allows characterizing networks beyond the degree distribution and uncovering some potential characteristics, Such as structural hierarchies, centrality and evolution. We analyze the core structure of some popular open source software and discuss the differences and similarities, get some noticeable properties, the result show the method provides an interesting view helping to comprehend and evaluate system in development.

The traction infinitely variable transmission (TIVT) used in the power train of electric vehicles (EVS) was designed. Firstly, based on the analysis of basic structure and working principle, the mathematic models were established on the transmission ratio, slipping ratio, transferring torsion and transmission efficiency; Secondly, Transmission characteristics of the TIVT were analyzed and calculated using ADAMS software. The calculation results show that: the export torsion varies with sway angle of steer ring as the import torsion is fixed. The transmission efficiency of TIVT is large when the motion of driving parts is pure-rolling or the slipping ratio is less. The efficiency could be reached more than 99% by rational designing. Theoretically, the driving distance of EVS matched with TIVT could be increased.

The Beijing government is taking measures to remit traffic congestions by restriction based on the last digit on a license plate, which influences the characteristic of traffic flow. This paper first builds a model about traffic flow characteristic, including vehicle velocity, roadway reliability and traffic congestion recovery time. The paper also researches different pattern of vehicle velocity before and after the rail number restriction, analyzes the changing trend of road-mobility reliability with traffic demands, and calculates the pattern of traffic congestion recovery time between the restrictions. The result indicates that when traffic flow’s density is large, the vehicle’s velocity is increased to 180% of the original after the restriction; and the recovery time from congestion to smooth is decreased to 75.8% of the original; after taken the restriction measures, the road unblocked reliability in Peak hours is increased, and the traffic condition ameliorate evidently.

Measuring the complexity of a large-scale software system has been a urgent demand in software development practices. The traditional software metrics can hardly describe the structural complexity in modern software. As the complex networks theory has been used to study the software structure, we analyzed a great many software systems. The analyzing results reveal the parameters in complex networks can be used to represent property of software structure. And this paper introduces some efficient metrics and measuring methods based on basic parameters in complex networks. A practice example was described to demonstrate the effectiveness of the metrics.