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271.
概念汽车与汽车设计的发展和创新 总被引:5,自引:0,他引:5
唐书民 《沈阳航空工业学院学报》2002,19(2):77-78
本文从概念汽车设计中的文化和科的角度,论述了概念汽车的设计对汽车工业发展的影响和作用。 相似文献
272.
在对月球采样返回任务需求及探测器系统任务剖面进行分析的基础上,设计并研制了一种轻量化、大负载、高精度、宽采样范围月球采样机械臂系统。该系统主要由4自由度机械臂及两种不同采样形式的末端采样器组成,可对不同指定区域浅层月壤进行铲、挖、浅钻等多形式采集。在综合考虑机械臂系统器上布局的基础上,基于运动学模型对采样机械臂的可达采样区域进行仿真分析,提出采样机械臂月面采样策略。基于等尺寸着陆器模拟平台,开展了针对3种不同密实度模拟月壤的采样试验,采样试验结果表明在可达采样空间内,采样机械臂对不同密实度月壤均具有较好的适应性,最大采样深度可达30 mm,最大单次采样量可达270 g,单次采样时间小于2 min。 相似文献
273.
Space science missions are increasingly challenged today: in ambition, by increasingly sophisticated hypotheses tested; in development, by the increasing complexity of advanced technologies; in budgeting, by the decline of flagship-class mission opportunities; in management, by expectations for breakthrough science despite a risk-averse programmatic climate; and in planning, by increasing competition for scarce resources. How are the space-science missions of tomorrow being formulated? The paper describes the JPL Innovation Foundry, created in 2011, to respond to this evolving context. The Foundry integrates methods, tools, and experts that span the mission concept lifecycle. Grounded in JPL's heritage of missions, flight instruments, mission proposals, and concept innovation, the Foundry seeks to provide continuity of support and cost-effective, on-call access to the right domain experts at the right time, as science definition teams and Principal Investigators mature mission ideas from “cocktail napkin” to PDR. The Foundry blends JPL capabilities in proposal development and concurrent engineering, including Team X, with new approaches for open-ended concept exploration in earlier, cost-constrained phases, and with ongoing research and technology projects. It applies complexity and cost models, project-formulation lessons learned, and strategy analyses appropriate to each level of concept maturity. The Foundry is organizationally integrated with JPL formulation program offices; staffed by JPL's line organizations for engineering, science, and costing; and overseen by senior Laboratory leaders to assure experienced coordination and review. Incubation of each concept is tailored depending on its maturity and proposal history, and its highest-leverage modeling and analysis needs. 相似文献
274.
科研管理创新的必由之路——并行工程 总被引:1,自引:0,他引:1
讨论国有企业存在的弊病;介绍并行工程的定义、要素和结构;论述科研管理体制创新的必要性。研究表明,企业必须进行流程再造,改造成“学习型组织”,实现“能本管理“,在型号研制中采用“并行工程”。才能在激烈的市场竞争中立于不败之地。 相似文献
275.
K. J. Seidensticker D. Möhlmann I. Apathy W. Schmidt K. Thiel W. Arnold H.-H. Fischer M. Kretschmer D. Madlener A. Péter R. Trautner S. Schieke 《Space Science Reviews》2007,128(1-4):301-337
SESAME is an instrument complex built in international co-operation and carried by the Rosetta lander Philae intended to land
on comet 67P/Churyumov-Gerasimenko in 2014. The main goals of this instrument suite are to measure mechanical and electrical
properties of the cometary surface and the shallow subsurface as well as of the particles emitted from the cometary surface.
Most of the sensors are mounted within the six soles of the landing gear feet in order to provide good contact with or proximity
to the cometary surface. The measuring principles, instrument designs, technical layout, operational concepts and the results
from the first in-flight measurements are described. We conclude with comments on the consequences of the last minute change
of the target comet and how to improve and to preserve the knowledge during the long-duration Rosetta mission. 相似文献
276.
计算机及其网络的使用使教育进入了信息化的时代。网络媒体使学校教育和社会教育发生很大的改变。通过对网络媒体的教育手段、教育形式、教育内容及教育后果的考察和研究,认为信息化教育存在巨大隐忧,应该通过加强人文教育来重构教育理念,消除信息化教育带来的负面影响。 相似文献
277.
The Faculty of Engineering at The University of Nottingham, UK, has developed interdisciplinary, hands-on workshops for primary schools that introduce space technology, its relevance to everyday life and the importance of science, technology, engineering and maths. The workshop activities for 7–11 year olds highlight the roles that space and satellite technology play in observing and monitoring the Earth's biosphere as well as being vital to communications in the modern digital world. The programme also provides links to ‘how science works’, the environment and citizenship and uses pixel art through the medium of digital photography to demonstrate the importance of maths in a novel and unconventional manner.The interactive programme of activities provides learners with an opportunity to meet ‘real’ scientists and engineers, with one of the key messages from the day being that anyone can become involved in science and engineering whatever their ability or subject of interest. The methodology introduces the role of scientists and engineers using space technology themes, but it could easily be adapted for use with any inspirational topic.Analysis of learners’ perceptions of science, technology, engineering and maths before and after participating in ENGage showed very positive and significant changes in their attitudes to these subjects and an increase in the number of children thinking they would be interested and capable in pursuing a career in science and engineering. This paper provides an overview of the activities, the methodology, the evaluation process and results. 相似文献
278.
Hans J. Haubold Werner R. Balogh 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009,43(12):1854-1862
Since 1991 the United Nations Office for Outer Space Affairs has been conducting a series of workshops on basic space science under its United Nations Programme on Space Applications. Up to 2004 the workshops focussed on capacity building efforts in basic space science, in particular for the benefit of developing countries. From 2005 onwards the workshops and their related activities contributed to the celebration of the International Heliophysical Year 2007. Together these activities and workshops constitute the United Nations Basic Space Science Initiative of the United Nations Office for Outer Space Affairs. This paper reflects on the achievements and outcomes of the Initiative and informs about considerations for its future evolution. 相似文献
279.
Sample return is an essential component of solar system exploration. Samples provide a unique data set that is critical for understanding formation and evolution of our solar system. This uniqueness is based on the scale of observations, precision of measurements, the ability to modify experiments as logic and technology dictate, and the ability to use instruments free of the constraints on mass, power, reliability, and data rate of flight instruments. Advances in analytical capabilities in recent years enable fundamental measurements to be made on extremely small samples, greatly reducing mass constraints on robotic sample return spacecraft. Sample studies provide irreplaceable ground truth for remotely-sensed data on planetary surfaces and fit within a variety of architectures for human exploration of the solar system. 相似文献
280.
本文论述了大学生科技竞赛活动对学校网络工程专业实践教学改革的促进作用。结合网络工程专业的教学实践,提出了重视科技竞赛,促进实践教学改革,提高学生学习兴趣和积极性的一些思路和做法。 相似文献