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1.
The authors conduct the experimental study and optimal computing for the condenser of automobile air conditioner. The especially the properties of heat transfer and flow at the side of air when using shutter fin. The authors the influence of several combinations of fin's geometry parameter to heat transfer and flow resistance. The maximal heat transfer is used as a criterion relation to select the fin's geometry parameters in the same facing air area of condenser. Furthermore, a program is designed to conduct optimal computing, and the computing results are basically consistent with experimental results. It shows that the optimal method is reasonable and the results can be applied to engineering practice.  相似文献   

2.
Taking into the feature of computer computing method, using Stress solution of elasticity theory and according to different method of solving of system of second order ordinary differential equations , this article provides two numerical value computing method as for the stress and deformation of the turbine impeller which is within the scope of elasticity . One combines the initial value computing method of system of ordinary differential equations (Runge-Kutta Method) with optimization method, another combines the boundary value computing method of system of ordinary differential equations difference method-with optimization method and three points interpolation method . The proposed method can eliminate the deficiencies of Secondary Calculation method and is particularly suited for programmable computer-based solution . The sample show that results gotten by two methods is nearly equal to the precise results,so they are practicable. They completes the quick and precise calculating of stress and deformation . They have some general meaning , large commonality and the project employing value.  相似文献   

3.
The parallel operation mechanism of 13 Bit lattice gas automata model, which can quickly compute and include more sites, is presented. Via coding and computing for particles of sites by bit, the parallel computing is achieved by transfering the particles propagation and collision into its backup and reloading. This mechanism can simulate correctly and validly some fluid motion with complex geometry boundary, such as flow through coke porous media. [WT5HZ]  相似文献   

4.
The exact computing of house architectural area and apportionment of area is strongly related to the actual interests of people. If it is done manually,there are many problem such as longer time spending, more workload, requiring detailed verification, nonstandard calculating report. Using ActiveX automation and ADO techniques, the house architectural area computing and plotting system was developed under Autocad R14 environment with VB 6.0 and Access database in order to solve above problem. The developed system can automatically compute house architectural area and apportionment of area for each floor of each building and can print the related data report and drawing. The system works well in many departments of house measurement. Several key technical problem of the system are discussed.  相似文献   

5.
针对重力式U型桥台背土相互作用,结合现行抗震规范,提出了4种分析模型及其力学本构关系和计算式。采用非线性时程法对比研究了某在建高墩双薄壁连续刚构桥的桥台背土相互作用效应。结果表明:只有弹簧模型可以求得与精细模型基本一致的高阶弹性模态;在纵桥向,滚轴模型和支座模型的结果都比精细模型小,弹簧模型相对精细模型的计算误差最小,关键内力误差不超过20%;在横桥向,支座模型的内力最接近精细模型,而弹簧模型和滚轴模型的结果都偏保守;桥台刚度对关键地震内力的影响幅度低于10%,而桥台有效参与质量的影响幅度也低于15%。综合考虑分析精度和计算成本,弹簧模型在抗震设计中更值得推荐。  相似文献   

6.
Tower structures are important device in the chemical equipment. They were lifted up by pulled down shearlegs. Tower structures' load is complex and changeful within lifting up. It is multifarious to analyze and to compute. At present, because people always adopts experiential or static analyzing and computing, one neglects changed circumstance and can adopt irrationally kinds of measures. It leads to break down tower structures and be lost in lifting up. This paper deduces computing formulae of danger case and provides basis for design for technics of lifting up according to analyze movement.  相似文献   

7.
Texture of apple fruit originates from anatomic traits related to cell wall architecture and is one of its most important quality characteristics, thus there is the desire to better understand the different factors which contribute to apple texture. Here we present a novel approach based on the simultaneous profiling of the mechanical and acoustic response of the flesh tissue to compression, using a texture analyzer coupled with an acoustic device. The methodology was applied to a 86 different apple cultivars, measured after two months postharvest cold storage and characterised by 16 acoustic and mechanical parameters. Statistical treatment of the data with principal component analysis (PCA) allowed for the identification of three groups of variables, the mechanical ones being clearly distinguished from the acoustic ones. Moreover, the distribution of the apple cultivars in the multivariate PCA plot allowed characterisation of the cultivars according to their textural performance. Each cultivar was analyzed also with non-destructive vis/NIR spectroscopy in order to determine impartially the ripening stage. Sensory evaluation by panellists was performed on a selected group of cultivars and sensory data correlated with the acoustic-mechanical data. The results demonstrate the good performance of our combined acoustic-mechanical strategy in measuring apple crispness as it is perceived by human senses.  相似文献   

8.
Intrusion detection system is an essential component of network security protection mechanisms. Most intrusion detection system can not adapt the variation of network environment. Aiming at this problem, an adaptive strategy that composed of condition space and strategy space is proposed. The condition space describes the network environment and the strategy space describes the strategy. There is an exclusive strategy corresponds to a certain environment state in condition space. On the base of the adaptive strategy, an adaptive intrusion detection system based on agent and data mining is designed. The simulation experiments indicate that the adaptive strategy is effective.  相似文献   

9.
According to the especial mechanical properties of bio-soft tissue materials, we design a mechanical test system of bio-soft tissue moterials which is controlled by microcomputer and can execute the post-processing for bio-soft tissue materials. The system can solve better the problems of reliability and accuracy appearing in the test of the mechanical properties for bio-soft tissue materials,and the test is convenient as well as speedy,and provides an effective experimental means for the study of biomechanics.  相似文献   

10.
The efficiency of the steel pushing V belt continuously variable transmission is an important factor for weighing CVT performance.Based on the mechanical analysis,by synthetically considering the effect of the viscosity lubricant on the power loss of CVT, the calculation formulae of efficiency have been found. The calculation simulationof efficiency is done, qetting two efficiency trend charts. One is efficiency with torque and rotational speed variation .The other is efficienccy with torque and ratio variation. The two charts have a guiding function in formulating matching and a control strategy and in an efficiency experiment.  相似文献   

11.
The objectives of this review are to analyse the potential of bioenergy crops development in European agriculture and to identify research objectives based on transformation technologies. Bioenergy is the chemical energy stored in organic material, which can be directly converted into useful energy sources by biological, mechanical or thermochemical processes. The substitution of food crops with energy crops and the demand for agricultural raw materials for liquid biofuel production will affect agriculture over the next decade and possibly beyond. It is expected that both second-generation biofuel production technology and energy crops used will be more efficient than first-generation. Nonetheless, there are still technical limitations for crop growth and fuel production from second-generation technology. In general, many of the crops that could supply the raw materials for second-generation biofuels are largely undomesticated and are in the first stages of development and management. The development of specific crops dedicated to energy has been proposed as a strategy to produce energy without affecting food security and the environment. The research seeks to develop enzymatic systems for the cost-efficient decomposition of cellulose into its molecular sugar components, which can then be fermented to produce ethanol. This biorefinery of crops into multiple products, including energy, chemical products and materials, will augment the overall value of the biomass. Clearly, multidisciplinary research is necessary to address sustainable biofuel production.  相似文献   

12.
Nonlinear thermophysics parameters are considered in ansys finite element software, so it can be used to compute temperature in the quenching. The temperature field in quenching process of 45 steel part is simulated by ansys finite element software, and the relationship between temperature of part and quenching time is obtained. Simulation result is correspondent with real process, this method has quick computing speed, and it can optimize quenching technology and select quenching bath. The most of all,this method can supply the temperature condition in computation of thermal stress and residual stress of quenching process.  相似文献   

13.
Magnetorheological materials are a class of smart materials whose reological properties may be rapidly varied by application of magnetic field. By a simple mechanical mold, a visco-plastic model for the materials is developed. It is shown that the model can describe the variation of the mechanical properties for the Magnetorheological materials in the different magnetic field. The result is shown that the model can characterize the mechanical properties of Magnetorheological Materials in plastic and viscous variation.  相似文献   

14.
改进遗传算法在饲料配方设计中的应用   总被引:1,自引:1,他引:0  
针对现有饲料配方软件的局限性,以白绒山羊饲料配方为例,提出一种基于改进遗传算法的求解方法。与标准遗传算法相比,采用随机联赛选择替代轮盘赌模型,优化了选择策略;采用不同的随机数交叉和高斯变异,改进了交叉算子与变异算子。测试结果表明,该方法具有良好的运算效率,拓宽了搜索空间,提高了对重点区域的搜索能力,降低了成本,为复杂问题的优化提供了一种新的思路。  相似文献   

15.
Radial Basis Function Neural Networks(RBF NN) are frequently used for regression prediction.But kernel matrix computation for high dimensional data source demands heavy computing power.To shorten computing time,the paper designs a parallel algorithm to compute the kernel function matrix of RBF NN and applies it to the prediction of converter re-vanadium modeling.The paper then implements the algorithm on a cluster of computing workstations using MPI.Finally,experiment is done with the practical data to study the speedups and accuracy of the algorithm.  相似文献   

16.
A new method of computing the cutter specifications and machine settings for the manufacture of spiral bevel and hypoid gears is studied. And a software system which includes the program models of new and old methods is developed. The system can perform the computations such as blank dimensions,cutting and grinding settings,tooth contact analysis and under cut check of SGM,SFM,SGT,SFT,HGM,HFM,HGT,HFT cutting methods. The new method can allow the user to give the position and length of contact pattern,the direction of contact path and the relative anglar acceleration. The system can be easily operated.  相似文献   

17.
The purpose of a parallel hybrid electric vehicle(PHEV) is for the best energy distribution between internal-combustion engine(ICE) and electric motor though the appropriate control strategy.It can not only keep the advantage of the ultra-low emission of electric vehicles(EV),but also take advantages of the hyperbaric energy of ICE.Simulation model for PHEV is built based on CRUISE,an auxiliary control strategy is designed,and then parameter simulation study on the control strategy is performed.The simulation results show that according to the different control requirements,the vehicle performance can be improved by adjusting!the corresponding control parameters.  相似文献   

18.
A method of constructing GPS-based positioning services system by means of JAVA technology is introduced in this paper. The position data, which are sent from GPS satellites, are received by GPS receiving terminal and are analyzed by mobile computing client developed on J2ME in accordance with the differential GPS algorithm. The client submits special position querying information to position server in way of wireless GPRS network. After computing and data querying, the server developed by J2EE returns results to the mobile device. Then, the mobile computing client displays the position map or carries out further processing. All of these form a highly precise location-based services system.  相似文献   

19.
A strategy for induction motor control based on the grade of errors is developed to improve the performance of hybrid vehicle drive system. The stator flux error, electric magnetic torque error and flux position angle are used as control variables, and rules for the switching states are chosen according to the errors and the principle of the Direct Torquc Control. This strategy improves efficiently the electric magnetic torque response of the system. The result of simulation shows that this strategy is an ideal control strategy of hybrid vehicle, which can make the motor generate the electric magnetic torque efficiently, steadily and quickly.  相似文献   

20.
This paper presented the principle and combinations of the mechanical transimssion test-bed with mechanical closed cycle and electric closed cycle. This system is composed of variable velocity driver, motor, generator, inverter and computer. It can be used both in mechanical closed cycle test-bed and electric ciooed cycle test-bed. The test-bed can keep a realting monitoring over the system and control the rotational speed and torque by computer. It can also simulate the real work condition of the test and to do the test. In this paper,the diminishable magnetization velocity modulation,invertiable control,the test data and curve,and the inverting efficiency as well as control scheme and presented.  相似文献   

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