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1.
In 1996, the National Research Council's Committee on Risk Characterization argued convincingly for the implementation of more participatory approaches to improve policy making by incorporating a wide range of stakeholder values and concerns in policy decisions. Guidance about how to best carry out such an approach in an agency like NASA is less clear. To address this gap, this paper discusses how the use of a structured approach to involve expert and non-expert stakeholders in policy making can improve the quality of stakeholder involvement and resulting decisions for space policy making at NASA. Supporting this discussion are results from two recent experiments. One compared the quality and type of participants’ input in a conventional stakeholder workshop with that of a more structured participatory process. The results from this experiment showed that a structured decision approach leads to more thoughtful and better-informed decisions. A second experiment showed that structured, participatory decision processes can help to legitimize space policy decisions after they have been implemented, leading to future benefits for the space agency.  相似文献   

2.
The space sector has frequently been confronted with cost overruns, with a negative impact on its management reputation. There are many reasons for this effect, the main one being that space development contracts are unique and often do not allow proper cost benchmarking. On the other hand, tools have been developed to minimise this effect and it is important to train future space managers in applying such tools. In the International Space University, such methods are illustrated with workshops, which aim to be as close as possible to reality. This article will describe the different techniques, memo-technically called the 5C approach here, and develop the use of a computerised tool, PRICE, to support these techniques in the different phases of the projects.  相似文献   

3.
China's space technology has gradually improved from the early stages' introduction, absorption and re-innovation based on backward design to independent innovation based on forward design. It is necessary to develop a new approach of systems engineering to improve the quality and efficiency of space systems design considering the large number of original design problems expected in the future. Adopting Model-Based Systems Engineering(MBSE) and Digital Twin method are important development initiatives in the field of modern engineering design. In the initial phase of system design, it is necessary to generate firm system architecture models based on the needs of stakeholders. The quality of the system design in this phase has a great impact on the detailed design and implementation for the subsequent system, and also plays an important role in the performance, development progress and cost of the whole system. Through the collaboration of cross-professional teams, modeling and model execution, comparing the model execution with expected results, MBSE has enabled digital model-level verification and validation before test verification and validation based on physical products, thus improving the design exactness, completeness and greatly reducing design errors or defects. This paper explores the logical ideas behind modeling of system architectures in order to promote the adoption of MBSE in the field of space systems.  相似文献   

4.
Space systems play an important role in today's society by generating or transmitting information from source to sink(s). The acquisition of the space system is often justified by the type, quantity and quality of information provided or transmitted. This work posits that the value of a class of space systems derives from and can be assessed through the value of information these systems provide. To this effect, a Bayesian framework is developed to assess system value in which systems are viewed as information sources, and stakeholders as information recipients. Information has value to stakeholders as it helps to update their beliefs, enabling them to make decisions that can yield higher expected pay-offs than in the absence of information. This increase in expected pay-offs is ascribed to the value of the system. Based on this idea, a new metric, Value-of-Design (VOD), is introduced to quantify the value of a class of space systems with unpriced services. The Bayesian framework assesses the Value-of-Design for the space system by considering the impact of the information transmitted on the actions taken by stakeholders, and estimating the resulting pay-offs from these actions. The framework here developed is then applied to the case of an Earth Science satellite that provides hurricane information to oil rig operators in the Gulf of Mexico. Probability models of stakeholders’ beliefs, and economic models of pay-offs are developed and integrated with a spacecraft design tool. Results from the application point to clusters of payload instruments that yielded higher information value, and minimum information thresholds below which it is difficult to justify the acquisition of the system. Additionally, the system is analyzed in Cost-VOD trade space to provide program managers with additional insights into the coupling of a system's predicted value generation and its associated lifecycle cost.  相似文献   

5.
This article explores the use of scenario analysis as a methodology to rigorously analyze potential space futures, particularly with respect to space security challenges, in the context of rapid and uncertain change across several dimensions of human space activities. The successful use of scenario analysis in other (e.g. corporate and military) sectors is described and results of an initial scenario analysis workshop are presented. Scenario analysis is recommended as a promising approach to evaluating the long-term consequences of various policy choices in the context of uncertainty, and as a process well-suited to fostering communication and building consensual knowledge among diverse stakeholders.  相似文献   

6.
A. McLean  A. Swankie 《Space Policy》1998,14(2):107-114
Helios is the only example of a multilateral collaborative military space effort currently being pursued within Europe. As such, a unique tripartite project, the first generation of the programme has had significant successes, even though the project has been faced with severe spending constraints and hindered by political obstacles. Helios 2, on the other hand, is not faring quite as well. Plagued by problems, the project has been in effect grounded indefinitely by German reluctance and inability to finance their share of the proposed three satellites. This paper assesses the origins and development of the Helios programme, and the difficulties facing the second generation of this satellite system.  相似文献   

7.
空间可展开天线结构研究进展   总被引:20,自引:3,他引:20  
扼要综述了空间可展开天线结构的发展及目前的国际动态,叙述了空间可展开天线结构、设计及分析中的主要研究课题及其目前的进展。指出“把多体动力学与有限元法相结合的综合动力学建模法”、“辩识模型后,用预测控制和优化的思想进行展开过程控制”、“用多约束优化法调整网状天线反射面形状精度”等是适合我国目前状况的较好方法。  相似文献   

8.
With the beginning of space era, a new branch of medicine has arisen and has been developing along with human exploration of outer space. And even though space medicine mainly faces the same problems as traditional medicine--cosmonauts health care and their high efficiency--this branch, has its own features, associated with the unusual factors of space flight, of which weightlessness is the major one. During the development of manned cosmonautics (duration of a human stay in space has reached already 438 days), methods of cosmonauts medical support and monitoring of their condition have been developed, knowledge of human possibilities and methods of process of organism adaptation to various and frequently severe conditions of external environment have increased. All this led to the fact that nowadays space medicine can become useful for improvement of human health care not only in space but also on the Earth. Moreover, the problem of implementation of cosmonautics achievements, and in particular of space medicine, in practice of public health care presents one of the most important issues concerning human health care. It is also connected with public opinion which is more and more concerned about the efficiency of significant expenses on space activities, especially lately. People often are set by the questions: what has space given, what fruits has space research provided to mankind, which results of this research can be used on the Earth already today for improvement of their life, for discussion of many difficult earthly problems? In terms of using cosmonautics possibilities, its achievements for health care and treatment, it is possible to define a few branches, in which purposeful studies are carried out.  相似文献   

9.
Satellite services benefit civil society by helping tackle challenges such as climate change, the digital divide, etc. They have the potential to deliver concrete benefits to European society through innovative services supporting economic, societal and environmental policies. Such benefits can trigger increased public support for space in Europe. However, this potential has yet to be achieved. This paper argues that technological bias, the diversity of interests and initiatives among stakeholders and their individual actions do not always serve their collective objective to ensure wide diffusion of satellite services. It draws on theories of diffusion of innovation and on its authors' participatory work with the space and the user communities and at their interface in an effort to help diffuse satellite services within civil society. One of the major causes of insufficient service diffusion is the weakness of the interface between the space and user communities; some of factors that currently contribute to this state of affairs are the space community's over-reliance on publicly financed, technical demonstration projects as solutions to service diffusion; insufficient coordination by public authorities of innovation policies and programmes with other public policies and objectives; and an insufficient integration of satellite services within users' culture, traditional tools and services. The discussion allows for conclusions to be drawn on how the system of stakeholders could function better in order for satellite services to be successfully diffused in Europe.  相似文献   

10.
Julie Abou Yehia   《Space Policy》2008,24(2):113-115
An initiative was undertaken by the European Space Policy Institute (ESPI) on 10–11 December 2007 to shed new light on the various threats to long-term sustainability on Earth using an interdisciplinary approach. The main objective of this conference was to analyse how space could be a tool for prediction, management or mitigation of threats and risks in six sectors (environment, security, mobility, knowledge, resources and energy) defined by ESPI as the main areas for sustainability. For each sector, one (non-space) speaker from a think-tank covering the respective sector and two speakers from the space sector exchanged views and ideas in order to identify common needs for action to ensure sustainability in the field. Such a dialogue between sector specialist and space experts permitted a detailed examination of the way space has become a crucial tool in solving a variety of today's problems. It also identified areas where space applications could better respond to sectoral and future challenges.  相似文献   

11.
《Acta Astronautica》2010,67(11-12):1625-1632
Excellent essays have been recently published on the profitability and the future of space tourism. This paper is intended to supplement the considerations in this field and emphasizes the further potential evolution of commercial personal spaceflights. Indeed, based upon work done at the International Space University (ISU) the oligopolistic character of suborbital space tourism has been linked to marketing and product life cycle (PLC) considerations and has led to the thesis that space tourism as a profitable sector will require a follow-on strategy. Orbital space tourism, on one hand, could become an extension of the PLC but, on the other hand, it is assumed that point-to-point (P2P) commercial space transport will become the long term sustainable market. Without ignoring technical challenges, this paper will mainly concentrate on marketing and commercial aspects of personal spaceflight.  相似文献   

12.
The present investigation is focused on the solution of a dynamic inverse problem which is concerned with the assessment of damage in large space structures by means of measured vibration data. This inverse problem has been presented as an optimization problem and has been solved through the use of the conjugate gradient method with the adjoint equation, also called the variational approach. When a high number of damaged elements has to be found and these elements are also severely damaged, it is shown that the use of an additional method is necessary in order to provide a better initial guess for the conjugate gradient method. A stochastic method, represented by the genetic algorithm method, has been chosen because it provides robust search in complex spaces and also reduces the chance of converging to local optima. The application of this hybrid approach showed that better results can be achieved, although the computational time for the application analyzed here could increase. The damage estimation has been evaluated using noiseless and noisy synthetic experimental data, and the reported results are concerned with a space truss structure.  相似文献   

13.
The international community is entering an era of shared global utilities from space and is increasingly reliant on space systems and activities that support a myriad of applications and utilities on Earth. A growing number of states are seeking to develop or extend their space capabilities. At the same time, a variety of non-state actors are also extending their involvement in space activities. The United Nations is the principal inter-governmental forum to deal with various space issues of global importance. Moreover, the United Nations system itself has become increasingly reliant on space systems for its day-to-day operations. In order for the United Nations to play its necessary role in the space arena, it will need to be supported by a space policy. A United Nations space policy would provide over-arching guidance on space activities for UN stakeholders in the space arena; it would inform UN participation in space activities and would promote improved coordination and cooperative governance of outer space activities. A world without a common UN space policy will not be able to respond to the challenges of the rapidly evolving space arena in the 21st century.  相似文献   

14.
The space programme of the former USSR has been in disarray since the disintegration of the Soviet empire and it faces formidable economic and political problems. Attempts are being made, however, to formalize a programme for the Commonwealth of Independent States (CIS) and a Russian space agency has been established. A senior Russian scientist here gives his personal view of the past, present and future of his country's space activities. He emphasizes the need to take advantage of new opportunities for cooperation, argues for the lifting of US restrictions on technology transfer and stresses the importance of space technology in monitoring environmental problems. This should remain a top priority.  相似文献   

15.
为同时兼顾千米量级尺度空间太阳能电站聚光系统的在轨发射安装难度、光学收集效率、稳定性及结构工艺等多方面的因素,提出采用基于球面正多面体的经纬线划分法模块化构建球形聚光器。该方法不仅可实现基础划分单元分布均匀、规格种类少,降低在轨构建与运载发射难度。而且只要合理控制弧高等分数和基础划分单元的口径就可以同时保证聚光系统的光学收集效率。理论与仿真结果显示,当弧高等分数为24时,该划分法共有25种基础单元件,整个球面被分成5762块。并且此时模块化构建的实际球形聚光器的光学收集效率与理想球面相比基本保持不变,解决了太阳能电站聚光系统设计中存在的关键问题。  相似文献   

16.
The mission's success fully depends on the Payload Operations conducted during the space flight. The Ground Team has to be trained to assist the Space Crew, to replan the cosmonaut's activities when contingengies occurr onboard and to change or cancel Payload activities when required. In order to act efficiently during the mission, the Ground Team must be prepared in advance of the flight and able to operate special tools for tracking the mission's progress, anticipating problems and taking decisions in realtime.

This document sets out the approach for conducting such a preparation for Ground Operation. It will be focused on the Altaïr mission performed in July 1993 onboard the Russian Mir space station.  相似文献   


17.
The EVA space suit development in Europe   总被引:1,自引:0,他引:1  
The progress of the European EVA space suit predevelopment activities has resulted in an improved technical reference concept, which will form the basis for a start of the Phase C/D development work in 1992. Technology development work over the last 2 years has resulted in a considerable amount of test data and a better understanding of the characteristics and behaviour of individual parts of the space suit system, in particular in the areas of suits' mobility and life support functions. This information has enabled a consolidation of certain design features on the one hand, but also led to the challenging of some of the design solutions on the other hand. While working towards an improved situation with respect to the main design drivers mass and cost, the technical concept has been improved with respect to functional safety and ease of handling, taking the evolving Hermes spaceplane requirements into consideration. Necessary hardware and functional redundancies have been implemented taking the operational scenario with Hermes and Columbus servicing into consideration. This paper presents the latest design status of the European EVA space suit concept, with particular emphasis on crew safety, comfort and productivity, in the frame of the predevelopment work for the European Space Agency.  相似文献   

18.
Preventing the weaponization of outer space is one of the most relevant issues of the current space law debate. In recent years discussions on this issue have significantly increased in international fora, such as the UN Conference on Disarmament and the COPUOS. While it has not been possible to arrive at an agreed solution on how to efficiently deal with the problem of possible weaponization of outer space so far, several valuable proposals have been put forward. China and Russia, on the one side, and the European Union, on the other, have taken the lead in this respect. While the former have submitted a proposal for a draft treaty on the demilitarization of outer space, known as the PPWT, the latter has issued a Draft Code of Conduct for Outer Space Activities. Despite the differences between the two proposals, this paper proposes the development of a Chinese, Russian and European common approach aimed at preventing the weaponization of outer space. Although such a goal is undoubtedly challenging, some political and legal factors may enable such cooperation in the not-too-distant future.  相似文献   

19.
The exciting challenge of building a permanent space station has been taken up by the USA, and participation in its development has been offered to the USA's allies. European countries are faced with the dilemma of whether to cooperate or to try to develop an autonomous approach. This article discusses the opportunities for Europe in participating closely in the US project — particularly in providing pressurized modules based on the Columbus programme — and argues that it is an opportunity not to be missed.  相似文献   

20.
空间站大型伸展机构的运动稳定性分析   总被引:4,自引:0,他引:4  
从空间站大型伸展机构的运动特点和系统动力学方程出发,着重分析了该系统的稳定性判据。这一问题又可分为五个方面:姿态-伸展-振动耦合系统的分析方法,复杂大系统的分解集结方法,时滞系统和滞后系统的稳定性问题,Stick-Ship运动对系统对系统稳定性的影响,非线性非定常系数稳定性的一般解。其中还对接触、摩擦、碰撞问题,变拓扑系统,非光滑动力学系统等进行了专门的研究,分析了Lyapunov指数方法在这些特殊系统中的适应性。本文对空间站大型伸展机构的稳定性问题进行了较全面的分析,指出了目前在处理这类复杂大系统时存在的一些难点问题,为其设计和研制工作提出了理论基础。  相似文献   

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