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141.
小行星俘获(ACR)任务是美国Keck空间研究中心发起的一项深空探测任务。该任务计划选定一颗近地小行星,通过口袋式抓捕系统对其实施抓捕,并于2025年左右将其带回近月空间。文章介绍了ACR任务的内容和系统设计,具体包括:航天器总体构型、抓捕分系统、探测识别分系统和控制与推进分系统;对小行星抓捕的目标探测与识别、旋转匹配、抓捕、消旋、轨道转移等核心操作。基于ACR任务,提出了空间目标俘获技术的需求与应用、抓捕航天器系统设计的启示;基于我国目前的技术研究情况,总结分析了发展空间目标俘获任务所需的关键技术,如大功率柔性太阳翼、长时间大范围轨道机动、目标探测与识别、快速机动、目标抓捕与消旋。  相似文献   
142.
Financial pressures are forcing organizations to minimize operations costs. Although the easiest way to achieve this goal is simply to reduce operational requirements, often this is not possible. Therefore, automation must be employed. This paper discusses the system trade-offs that must be performed to maximize the impact of automation efforts. The discussion begins with the development of generic automation guidelines. Since many automation issues are program-specific, the paper addresses the application of these principles to operation of the ORBCOMM satellite constellation. This example demonstrates how automation can be used to produce a highly efficient satellite operations system.  相似文献   
143.
随着航空电子系统综合化程度的不断提高,对数据总线的通信能力提出了更高的要求,此需求对于具备较高信息收集能力的特种飞机任务电子系统来说尤为突出.本文提出了一种基于航空全双工交换式以太网(AFDX)的特种飞机任务电子系统构建思路,并对其进行了分析与验证.  相似文献   
144.
无人机自主控制等级及其系统结构研究   总被引:7,自引:1,他引:6  
陈宗基  魏金钟  王英勋  周锐 《航空学报》2011,32(6):1075-1083
正确制定无人机(UAV)自主控制等级,有利于了解中国无人机所处的自主控制水平,也有利于为中国无人机自主控制技术的发展提供正确的指导方向.鉴于无人机自主控制等级应该是由无人机代替有人驾驶飞机所能完成的驾驶员的智能行为等级这一认识,从人类智能活动的机理分析,给出了人类的智能控制行为等级.然后,在深入分析美国无人机自主控制等...  相似文献   
145.
Sample return from small solar system objects is playing an increasingly important part in solar system exploration. Critical to such missions is a robust, simple, and economic sample collector. We have developed a collector such as this for near-Earth asteroid sample return missions that we have termed the Touch-and-Go Impregnable Pad (TGIP). The collector utilizes a silicone substrate that is pushed into the dust and gravel surface layer of the asteroid. As part of a systematic evaluation of the TGIP, we have investigated the resilience of this substrate to ionizing radiations. Several miniature versions of the collector, containing typically ∼3 g of the collection substrate, were exposed to 0.564 MeV beta particles from a 90Sr source and a 6 MeV electron beam in a linear accelerator to simulate the wide range of energies of solar and galactic ionizing radiation. Various radiation levels up to eight times greater than expected on a six-year asteroid mission (in the case of beta radiation) and 50 times greater than expected (in the case of the 6 MeV electron radiation) were administered to the substrate. After irradiation, the efficiency of the substrate in collecting samples of mock regolith was compared with that of collectors that had not been irradiated. No difference beyond experimental uncertainty was observed and we suggest that the operational TGIP will not be affected adversely by radiation doses expected during a typical six-year inner solar system mission.  相似文献   
146.
The human exploration of multiple deep space destinations (e.g. Cis-Lunar, NEAs), in view of the final challenge of sending astronauts to Mars, represents a current and consistent study domain especially in terms of its possible scenarios and mission architectures assessments, as proved by the numerous on-going activities about this topic and moreover by the global exploration roadmap. After exploring and analysing different possible solutions to identify the most flexible path, a detailed characterisation of several Design Reference Missions (DRMs) represents a necessity in order to evaluate the feasibility and affordability of deep space exploration missions, specifically in terms of enabling technological capabilities.The study presented in this paper was aimed at defining an evolutionary scenario for deep space exploration in the next 30 years with the final goal of sending astronauts on the surface of Mars by the end of 2030 decade. Different destinations were considered as targets to build the human exploration scenario, with particular attention to Earth–Moon Lagrangian points, NEA and Moon. For all the destinations selected as part of the exploration scenario, the assessment and characterisation of the relative Design Reference Missions were performed. Specifically they were defined in terms of strategies, architectures and mission elements. All the analyses were based on a pure technical approach with the objective of evaluating the feasibility of a long term strategy for capabilities achievement and technological development to enable future space exploration.This paper describes the process that was followed within the study, focusing on the adopted methodology, and reports the major obtained results, in terms of scenario and mission analysis.  相似文献   
147.
针对多目标多任务的深空探测轨道优化设计问题,基于以太阳为主引力体的二体模型,采用电推进小推力系统,提出了将目标行星的探测方式、探测顺序、发射窗口同时进行全局优化的解决方案.依此建立小推力轨道优化设计算法模型,利用微分进化算法进行全局一体化优化设计,得出多目标多任务的一体化深空探测轨道.通过与相同条件下其他设计方法的结果比对分析得出:基于小推力推进方式并采用微分进化算法进行优化的轨道优化设计方案,在多目标多任务深空轨道一体化设计问题上具有可行性及应用价值.  相似文献   
148.
介绍了飞机的飞行品质评估典型任务,初步建立了飞行员行为特性数学模型以及飞行品质自动评定专家知识库,开发了基于试飞员模型的飞行品质评定软件的设计与实现;在六自由度动基座飞行模拟器上,针对某高教机电传飞控系统进行了飞行模拟器部分典型任务的飞行品质自动评估,其评估结果与飞行员评估结果基本吻合.该技术应用于飞控系统控制律设计、优化中,能提高设计效率,节约主观评定的时间,是客观飞行品质评定的有力补充.  相似文献   
149.
《中国航空学报》2020,33(3):965-977
Accurate and highly efficient approaches to obtain mission opportunities are still the goals of mission planners of interplanetary explorations. The search for launch opportunities not only determines the specified launch window of the mission but also presents the performance requirements for the interplanetary probe and its launch vehicle. An effective method, namely the two-dimensional launch window method, is developed from a completely new perspective to determine all the launch opportunities of the mission in this research. For a fixed launch time, the method to determine all the time windows in the dimension of Time-of-Flight (TOF) is firstly proposed and these time windows represent all the launch opportunities for the given launch time. And then, the two-dimensional launch window method is proposed, which computes the time windows in both the launch time and TOF dimensions to achieve all launch opportunities of the mission. Numerical examples are provided to demonstrate the accuracy and high efficiency of the method. Compared with the widely-used pock-chop plot method, the proposed method reduces the computational time by two orders of magnitude for the same search precision, and thus is especially suitable for the cases involving rapid, high-precision, and/or large-scale searches for mission opportunities.  相似文献   
150.
对于载人地月转移任务,应急返回轨道是航天员安全返回地球的保障。针对载人混合轨道地月转移对安全性要求高的特点,基于载人地月混合轨道,提出了3种一次脉冲的应急返回轨道,即直接返回、即刻机动绕月返回及绕月后机动返回等模式。研究了不同时刻发生故障后,利用3种应急模式返回地球的转移时间和速度增量等特性,研究了载人地月转移全过程出现故障后的应急方式,总结了3种应急模式的应用特点及优劣,可为载人月球探测任务顶层任务分析与设计提供参考。  相似文献   
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