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161.
产品的设计色彩与人的情感心理 总被引:4,自引:0,他引:4
刘涛 《沈阳航空工业学院学报》2000,17(4):84-86
本文讨论了色彩在工业设计中的应用,并通过色彩构成的色相,明度,纯度等概念的探讨,说明了不同的色彩给人以不同的感觉,产生不同的情绪,并进一步说明了色彩在产品设计上的作用与人的心理情感的关系。 相似文献
162.
Judith Lapierre Stphane Bouchard Thibault Martin Michel Perreault 《Acta Astronautica》2009,64(11-12):1304-1313
A simulation for flight of international crew on space station took place in Moscow from July 1999 to April 2000 (SFINCS) at the State Biomedical Institute of Russia (IBMP) isolation chambers. Objectives of this study were to identify concepts of psychosocial adaptation and of social interactions to develop an explanation of the transcultural group performance. Method: constructivist epistemology with grounded theory research and fourth generation evaluation were used. Data on processes and interactions were gathered during 110 days of confinement as a subject and extended to 240 days as an outside scientist. Results indicate that coping is influenced by usual coping strategies and coping behaviors inside. Several stresses and human factor issues were identified altering well being and performance inside the chambers. Enabling and limiting forces are discussed. A theory on transcultural group performance is proposed. Issues are raised that appear critical to selection, training and group performance. 相似文献
163.
刘国华 《郑州航空工业管理学院学报(管理科学版)》2003,21(1):48-50,66
根据社会发展对档案工作的客观要求以及档案工作自身生存、发展的需要,对影响档案信息深层次加工的因素进行了分析,提出了关于档案信息进行深层次加工的对策。 相似文献
164.
统筹图中求有关参数的权关联矩阵算法 总被引:7,自引:1,他引:6
给出一个求统筹图中有关参数的数值算法,证明了算法的理论依据,并举例说明算法的应用。 相似文献
165.
深入认识翼型动态失速,结合有效流动控制手段,对解决直升机、风力机桨叶等动态失速引起的高阻力、大低头力矩等气动问题具有重要意义。本文首先介绍了翼型动态失速的流场特点和危害,进而分析了缩减频率、雷诺数、马赫数以及翼型型面等参数对动态失速的影响,并在此基础上总结了常见的动态失速流动控制方法及其研究进展。等离子体气动激励易于产生快速、可控的宽频带气动激励,在动态失速控制领域具有潜力,本文着重介绍了等离子体气动激励动态失速控制的概念和流动控制原理,总结了近来年等离子体激励在翼型动态失速控制上的进展。 相似文献
166.
固定网格技术避免了沿结构边界繁琐的网格划分过程,在复杂几何结构分析时具有很大优势。建模精度和分析精度是采用固定网格进行结构分析的两大难题。文中针对固定网格分析中的建模精度问题,提出了一种由CAD模型至分析模型的快速转换方法,首先将CAD模型采用边界描述,然后通过射线交点法来区分固定网格中单元的属性,并借助四叉树/八叉树技术实现对边界网格的细分。最后采用加权B样条有限胞元法来保证CAD模型在固定网格中的分析精度。本文建立了一种由结构CAD模型至固定网格仿真分析的设计框架,数值算例表明了该方法的有效性。 相似文献
167.
《中国航空学报》2021,34(5):466-484
Turbocharging is an efficient approach for addressing power reduction and oil consumption increase in aviation piston engines during high-altitude flights. However, a turbocharger significantly increases the complexity of a power system, and its considerably complex matching relation with the engine results in a coupling of failure modes. Conventional analytical methods are hard to identify failure-inducing factors. Consequently, safety issues are becoming increasingly prominent. This study focuses on methods for identifying failure-inducing factors. A whole-machine system model is established and validated through experimentation. The response surface method is employed to further abstract the system simulation model to a surrogate model (average error: ~ 3%) in order to reduce the computational cost while ensuring accuracy. On this basis, an improved Correspondence Analysis (CA)-Polar Angle (PA)-based Classification (PAC) is proposed to identify the key factors affecting the failure mode of turbochargers. This identification method is based on the row profile coordinates G varying with the numerical deviations of the key factors, and is capable of effectively identifying the key factors affecting the failure. In a validation example, this method identifies the diameter of the exhaust valve (e2) as the primary factor affecting the safety margin for each work boundary. 相似文献
168.
In this paper, the problem of moving target localization from Bistatic Range(BR) and Bistatic Range Rate(BRR) measurements in a Multiple-Input Multiple-Output(MIMO) radar system having widely separated antennas is investigated. We consider a practically motivated scenario,where the accurate knowledge of transmitter and receiver locations is not known and only the nominal values are available for processing. With the transmitter and receiver location uncertainties,which are usually neglected in MIMO radar systems by prior studies, taken into account in the measurement model, we develop a novel algebraic solution to reduce the estimation error for moving target localization. The proposed algorithm is based on the pseudolinear set of equations and two-step weighted least squares estimation. The Cramer-Rao Lower Bound(CRLB) is derived in the presence of transmitter and receiver location uncertainties. Theoretical accuracy analysis demonstrates that the proposed solution attains the CRLB, and numerical examples show that the proposed solution achieves significant performance improvement over the existing algorithms. 相似文献
169.
针对卫星电源系统短路故障导致母线电压跌落、业务中断甚至整星失效的问题,分别采用电路模型和数学模型的方法对短路后母线电压的暂态特性进行分析,指出故障持续过程经历母线电容放电、太阳电池阵动作、放电调节器动作、蓄电池经二极管直接供电这4个阶段,分析了各阶段母线电压的暂态响应及转换条件。随后,研究了发生稳态电压跌落的条件及其影响因素。针对航天器通常使用的快速熔断器保护,分析了母线电压跌落受熔断I~2T、短路通路阻抗、蓄电池内阻、蓄电池开路电压的影响程度。依据暂态特性的分析,提出接地优化方法以及蓄电池开路电压、短路通路阻抗和欠压保护点的配合设计方法,使得短路暂态过程母线电压跌落程度满足系统关键单机运行的需求。 相似文献
170.
《中国航空学报》2020,33(10):2620-2632
The gears in aero-engines perform energy and motion transfer between the High-Pressure Rotor (HPR) and accessories. Firstly, an occurred fault with radial cracks in the driven gear disk was diagnosed as High Cycle Fatigue (HCF) failure through necessary examinations. Analysis of fault tree and test signals indicated that the fracture was relevant to the swing vibration of the driven gear excited by the unbalance excitation on HPR. Secondly, a corresponding mechanism model was established, in which the gear meshing effect was considered, with lateral and swing vibration mode. The Governing Equations (GEs) and the Finite Element Model (FEM) were established and verified. Then, the modal shapes, harmonic response, and transient response were analyzed, indicating that the swing vibration of the driven gear could be significantly excited by the unbalance on HPR, which induced the cracks in the driven gear disk to extend radially. Furthermore, influences of factors on the unbalance response were obtained, in which the unbalance response appeared local minimum points and maximum points. Meanwhile, 1# and 2# bearing stiffness had rather significant influences on the response. Thus it is efficient to modify them to achieve vibration control. 相似文献