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32.
A method of technologic audit for technical re-equipment of enterprises is considered. The method developed is intended to verify technological solutions of projects of technical re-equipment of enterprises according to indicators of productivity.  相似文献   
33.
Real values of parameters for a space vehicle and its steering devices are specified by using the motion parameters measured in flight based on solving the differential equations of motion.  相似文献   
34.
The calculation of the design parameters of lifting airscrew systems with fixed and tilted rotor, including the investigation of the operation schemes of actuators for the propeller control system, is carried out.  相似文献   
35.
Safety factors of the Ansat helicopter main rotor blade are determined in the root section at various flight modes with taking into account the possible damages.  相似文献   
36.
The Magnetospheric Multiscale (MMS) mission will provide measurement capabilities, which will exceed those of earlier and even contemporary missions by orders of magnitude. MMS will, for the first time, be able to measure directly and with sufficient resolution key features of the magnetic reconnection process, down to the critical electron scales, which need to be resolved to understand how reconnection works. Owing to the complexity and extremely high spatial resolution required, no prior measurements exist, which could be employed to guide the definition of measurement requirements, and consequently set essential parameters for mission planning and execution. Insight into expected details of the reconnection process could hence only been obtained from theory and modern kinetic modeling. This situation was recognized early on by MMS leadership, which supported the formation of a fully integrated Theory and Modeling Team (TMT). The TMT participated in all aspects of mission planning, from the proposal stage to individual aspects of instrument performance characteristics. It provided and continues to provide to the mission the latest insights regarding the kinetic physics of magnetic reconnection, as well as associated particle acceleration and turbulence, assuring that, to the best of modern knowledge, the mission is prepared to resolve the inner workings of the magnetic reconnection process. The present paper provides a summary of key recent results or reconnection research by TMT members.  相似文献   
37.
力举"优裕、才智与环境"三大元素,围绕2010年上海世博会主题"城市,让生活更美好!",芬兰国家馆的设计,以其突出和未来实现"更美好生活"的理念而独树一帜。  相似文献   
38.
研究了射流方式对工具电极和工件之间的间隙中流场的影响,建立了相应的工作液和粉末微粒运动方程,提出并采用了新型射流方式,降低了加工件的表面粗糙度数值。  相似文献   
39.
基于CAPPFramework的智能化CAPP技术   总被引:5,自引:2,他引:5  
结合航空CIMS工程中飞机结构件集成化CAD/CAPP/CAM项目的研究开发 ,在CAPPFramework系统的基础上 ,深入研究了面向对象工艺知识处理技术、综合智能化技术等 ,进行智能化CAPP的应用与开发 ,实现了飞机结构件数控工艺的自动化设计 ,实现了信息集成和工艺设计与管理的一体化。  相似文献   
40.
Global ena Image Simulations   总被引:2,自引:0,他引:2  
Fok  M.-C.  Moore  T.E.  Wilson  G.R.  Perez  J.D.  Zhang  X.X.  Brandt  P. C:Son  Mitchell  D.G.  Roelof  E.C.  Jahn  J.-M.  Pollock  C.J.  Wolf  R.A. 《Space Science Reviews》2003,109(1-4):77-103
The energetic neutral atom (ENA) images obtained by the ISEE and POLAR satellites pointed the way toward global imaging of the magnetospheric plasmas. The Imager for Magnetopause to Aurora Global Exploration (IMAGE) is the first mission to dedicate multiple neutral atom imagers: HENA, MENA and LENA, to monitor the ion distributions in high-, medium- and low-energy ranges, respectively. Since the start of science operation, HENA, MENA and LENA have been continuously sending down images of the ring current, ionospheric outflow, and magnetosheath enhancements from high pressure solar wind. To unfold multiple-dimensional (equal or greater than 3) plasma distributions from 2-dimensional images is not a trivial task. Comparison with simulated ENA images from a modeled ion distribution provides an important basis for interpretation of features in the observed images. Another approach is to develop image inversion methods to extract ion information from ENA images. Simulation studies have successfully reproduced and explained energetic ion drift dynamics, the transition from open to closed drift paths, and the magnetosheath response to extreme solar wind conditions. On the other hand, HENA has observed storm-time ion enhancement on the nightside toward dawn that differs from simple concepts but can be explained using more sophisticated models. LENA images from perigee passes reveal unexpected characteristics that now can be interpreted as evidence for a transient superthermal exospheric component that is gravitationally-influenced if not bound. In this paper, we will report ENA simulations performed during several IMAGE observed events. These simulations provide insight and explanations to the ENA features that were not readily understandable previously.  相似文献   
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