The basic approach of protecting people from being hurt or killed in an accident is to improve crashworthiness of vehicles. This paper starts with discussing theories and methods for vehicle passive safety design, which included experiential methods, analytic methods, multi-body dynamics methods, crash test methods and the finite element method. Emphasis will be paid to the basic FEM theories and algorithms of impact problems. Topics discussed include the governing equation, element discretization, hourglass control, time integration, material model, shell element algorithms and contact-impact algorithms. For more reliable simulation results, this paper then conducts study on how to accurately get material model parameters by combining the FEM method with experimental method, and develops relevant material test machine and parameter calculating software. Based on that, basic typical impact simulation and test validation study are conducted. On the basis of the above work, the paper studies the thin-shell structures'crashworthiness, which was affected by the following factors: spot-weld features, shell thickness, cross-section and pre-deformation. As to vehicle parts'crashworthiness, the paper conducts simulation study of designing energy-absorbing steering system and adaptive airbag system. A practical energy-absorbing steering wheel is designed as an example. In further depth research, the paper suggests several inverse quantificational methods for vehicle crashworthiness design based on the ideal crash characteristics. The above theories and methods are applied with good results through several practical vehicles' crashworthiness design and improvement.

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A theoretical model is built to investigate the simulation of the infrared characteristic of the metal structure with the PCM false target.Structure parameters of the PCM false target that suit for the simulation are investigated numerically.According to the results,further request on the improvement of the thermal conductivity of PCM is presented.An experimental platform is built and the numerical model is validated experimentally.Three key thermal characteristic components of the false tank(barbette,wheel and front armor plate) are manufactured and tested,and good results are obtained.A method for the thermal conductivity enhancing of PCM by using aluminum fins is studied,the influence of the structure parameters of PCM plates to the simulation effects are investigated numerically,and the reasonable configuration parameters of the PCM plates used to simulate the steel plates of different thickness are obtained.In the study of the application of heat convection method in IR false target,a passive infrared simulation system is designed to simulate the infrared characteristic of metal constructions.The system is made up of pipe-plate,pump,receiver,and working fluid.

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The passive beam delivery system in the superficially-placed tumor therapy terminal at Heavy Ion Research Facility in Lanzhou, which includes two orthogonal dipole magnets as scanning system, a motor-driven energy degrader as range-shifter, series of ridge filters as range modulator and a multileaf collimator, is introduced in detail.

詳細介紹了蘭州重離子研究裝置淺層腫瘤重離子治療終端的被動式束流配送系統(tǒng)，對該束流配送系統(tǒng)重要組成部件及其整體的性能進行了實驗驗證亚洲午夜久久久。

The structure of the boron gravity-injection system which is compared with other external similar systems is presented. Its extrusive character in its structure design shows that it plays an important role in the development process of passive driven system.

介紹了重力注硼系統(tǒng)的結構YY6080午夜福利理论中文，并與國外設計進行了對比分析，指出了重力注硼系統(tǒng)在結構設計上的突出優(yōu)勢及在非能動系統(tǒng)發(fā)展過程中的重要地位超碰图片。

Like reforming outside the system in our country,we research the economic development in the minority region outside the system,that is winding out the minority factor.after the latent capacity of extensive increasing gives play to,the minority factor becomes impassable furtherly in the economic development of minority region,because it can not solute the problem that how to mix the minority factor with the problem of the economic development in minority region,the academic circle sinks into the passive condition of application and countermeasure study,adapt to this learning dilemma,the minority region is at a late-developing stage,ignoring the minority factor imitating simply the development and industrial model of the developed region is a fairly universal selection of economic development, Adapt to the selection.,On the development policy in the minority region,A high premium comes to be placed on the tilting of the policy and helping of the economic things.

與我國體制外改革相類似天堂资源最新版网页，長期以來我們對民族地區(qū)的經(jīng)濟發(fā)展也是"體制外"及繞開民族因素進行的，這種發(fā)展模式在粗放增長的潛力得到發(fā)揮之后欧美A性交，民族因素成為民族地區(qū)經(jīng)濟進一步發(fā)展不可逾越的因素影音先锋av强奸乱伦，由于無法解決如何融合民族因素和民族地區(qū)經(jīng)濟發(fā)展的問題，學術界陷入應用研究和對策研究的被動局面黄色网站在线观看18。

Television tracking system is a kind of passive image recognizing and tracking equipment. It can separate the targets form the field, certain their position, estimate their movement trend and realize the real-time tracking of the targets, at complicated background and according to standard television system type.

電視跟蹤雷達是一種被動式成像跟蹤設備欧美一级a欧美一级A，能在比較復雜的背景下按照標準的電視制式，提取與分離視場內的目標在线观看精品国产福利AV，確定目標位置日韩毛片无码一级观看免费，估計目標運動趨勢，實現(xiàn)對目標的實時跟蹤人人弄人人玩人人搡。

In order to measure the passive network's conduction automatically, a network conduction instrumentation based on FPGA technology was designed and implemented according to the design principle of Virtual Instrument. System adopted FPGA technology building a digital flat-top to imitatively produce the high quality sine signal. Under the control of C8051MCU, measurement, calculation and display of the port network's conduction were automatic implementation. Furthermore, the system has the function of frequency step measurement.

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In the experimental work, application of proportional controller to active vibration control incorporated with passive vibration isolator to suppress its resonant oscillation of natural frequency is studied in this project. Vibration acceleration acquired from accelerator is inputted to controller as feedback signal. The processed signal from controller is transmitted to voice coil actuator to control vibration. Firstly, based on the theoretical equations which govern the system vibration, the physical mechanism of active control in total system is studied.

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Methods By active surveillance system, and passive surveillance system (the reporting system of legally determined infectious diseases), surveilling influenza epidemiologically, etiologically, serologically and molecular epidemiologically.

通過主動監(jiān)測系統(tǒng)和被動監(jiān)測，對流感進行流行病學欧美日韩综合自拍小说网站、病原學国产网站自拍、血清學和分子流行病學監(jiān)測。

The feasibility of the two proposed methods is verified by computer simulation.4黄免费视频色、A single receiving station passive radar system framework based on Software Defined Radio is proposed. Receiving directly signal, scatted signal use an array antenna simultaneously in the radar system. Therefore, the hardware structure of the system is simplified, Maneuvering and Flexible design are improved.

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