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1.
Developments in remote-sensing technology have prompted suggestions that the news media could soon make routine use of newsgathering from space. A satellite system dedicated to this purpose (a ‘Mediasat’) could supply critical information. Government policy makers, however, fear that the media's use of such technology could affect national security, foreign relations and personal privacy. This article assesses US government policy on current and future newsgathering from space, and the technical potential for a Mediasat system. The authors raise doubts about the commercial viability of Mediasat, and point out that existing media sources already provide information on news stories. They conclude that concerns over the use of data from space will have to be met on a case-by-case basis as the media gain experience, using the same criteria now applied to balance the right of freedom of information with the need for national security.  相似文献   

2.
In this Viewpoint — an edited version of a statement made to the US House Committee on Science's Subcommittee on Space and Aeronautics' hearing on ‘US launch strategy’ — the President of Arianespace, Inc analyses the overriding importance of US government policies and executive decisions on the shaping and behavior of the international market in commercial space launch services. Chief among these is the overruling of commercial imperatives by foreign policy and national security interests and the consequent regular intervention of the US government in launch decisions. The ability of Arianespace successfully to compete in a market severely distorted as a result of these interventions, including the encouragement of joint ventures between US and Russian or Ukrainian companies, is explained.  相似文献   

3.
Management of health problems in limited resource environments, including spaceflight, faces challenges in both available equipment and personnel. The medical support for spaceflight outside Low Earth Orbit is still being defined; ultrasound (US) imaging is a candidate since trials on the International Space Station (ISS) prove that this highly informative modality performs very well in spaceflight. Considering existing estimates, authors find that US could be useful in most potential medical problems, as a powerful factor to mitigate risks and protect mission. Using outcome-oriented approach, an intuitive and adaptive US image catalog is being developed that can couple with just-in-time training methods already in use, to allow non-expert crew to autonomously acquire and interpret US data for research or diagnosis.The first objective of this work is to summarize the experience in providing imaging expertise from a central location in real time, enabling data collection by a minimally trained operator onsite. In previous investigations, just-in-time training was combined with real-time expert guidance to allow non-physician astronauts to perform over 80 h of complex US examinations on ISS, including abdominal, cardiovascular, ocular, musculoskeletal, dental/sinus, and thoracic exams. The analysis of these events shows that non-physician crew-members, after minimal training, can perform complex, quality US examinations. These training and guidance methods were also adapted for terrestrial use in professional sporting venues, the Olympic Games, and for austere locations including Mt. Everest.The second objective is to introduce a new imaging support system under development that is based on a digital catalog of existing sample images, complete with image recognition and acquisition logic and technique, and interactive multimedia reference tools, to guide and support autonomous acquisition, and possibly interpretation, of images without real-time link with a human expert. In other words, we are attempting to replace, to the extent possible, expert guidance by guidance from a digital information resource. This is a next logical phase of the authors’ sustained effort to make US imaging available to sites lacking proper expertise. This effort will benefit NASA as the agency plans to develop future human exploration programs requiring increased medical autonomy. The new system will be readily adaptable to terrestrial medicine including emergency, rural, and military applications.  相似文献   

4.
This paper examines the debate within the USA over how to meet the perceived competition from the successful European Ariane launcher and the loss of US market share for space launch services that it represented. In particular, it explores the origins of the 1983 Reagan Administration policy to turn over expendable launch vehicle production and operation to private industry. The Administration's other decisions to: (1) use the Space Shuttle to fly all government payloads, and (2) allow NASA to market Space Shuttle services commercially, conflicted with this commercialization policy. These policies effectively caused US industry to delay entry into the international competition for launch services until after the loss of the Space Shuttle Challenger in January 1986.  相似文献   

5.
The agreement by the USA and Cocom to allow the export of US-built satellites for launch on Chinese launchers raised the national subsidy issue. The international commercial launch market is multinational and highly competitive; launch suppliers have accused each other of being unfairly subsdized. Currently the US government is engaged in various negotiations to establish a ‘level playing field’. A clear study of the subsidy issue is essential. This article examines some of the charges and the current situation associated with each country and suggests a possible approach for the USA to remain competitive in the international commercial launch market.  相似文献   

6.
The recent interest in the use of ultrasound (US) to detect pneumothoraces after acute trauma in North America was initially driven by an operational space medicine concern. Astronauts aboard the International Space Station (ISS) are at risk for pneumothoraces, and US is the only potential medical imaging available. Pneumothoraces are common following trauma, and are a preventable cause of death, as most are treatable with relatively simple interventions. While pneumothoraces are optimally diagnosed clinically, they are more often inapparent even on supine chest radiographs (CXR) with recent series reporting a greater than 50% rate of occult pneumothoraces. In the course of basic scientific investigations in a conventional and parabolic flight laboratory, investigators familiarized themselves with the sonographic features of both pneumothoraces and normal pulmonary ventilation. By examining the visceral–parietal pleural interface (VPPI) with US, investigators became confident in diagnosing pneumothoraces. This knowledge was subsequently translated into practice at an American and a Canadian trauma center. The sonographic examination was found to be more accurate and sensitive than CXR (US 96% and 100% versus US 74% and 36%) in specific circumstances. Initial studies have also suggested that detecting the US features of pleural pulmonary ventilation in the left lung field may offer the ability to exclude serious endotracheal tube malpositions such as right mainstem and esophageal intubations. Applied thoracic US is an example of a clinically useful space medicine spin-off that is improving health care on earth.  相似文献   

7.
国有企业产权问题是国有企业公司制改革的核心.要做到产权明晰,必须正确认识法人财产权与股权的性质,把国家作为投资者对国有企业享有的股权与国有企业享有的法人财产所有权分开,改变传统的国有企业财产属于国家所有、国有企业是国家附属物的状况,赋予其独立的市场主体地位,使其得以独立地参与市场竞争.  相似文献   

8.
北京一号小卫星及其数据应用   总被引:7,自引:0,他引:7  
结合小卫星技术介绍了北京一号高性能对地观测小卫星计划和项目进展情况,综述了北京一号系统的主要组成和性能,并结合其数据特点,介绍北京一号遥感影像的示范应用和重点应用,探讨、分析了其更广泛的应用领域和良好的市场前景。  相似文献   

9.
Roland Deschamps, Secretary General of Arianespace, discusses the evolution of the Ariane family of launchers and the creation of Arianespace to market and manage Ariane production and launch services. Tha launcher market is analysed and the advantages of Ariane compared to the US Shuttle are identified.  相似文献   

10.
Has the current US space policy improved the USA's overall strategic position? Does it affect favorably international partnerships? These questions are examined in terms of security, political economy, and influence. In today's context, where there are more space players, more options, more potential for unintended consequences, and higher stakes, unilateral action is more limited in its effectiveness than in earlier times. Surveying current US space policy, it is not clear that data-driven, analytically based decisions are being made to affect positively national independence, innovation, market creation, and international perceptions of the USA as a trustworthy partner. More promising are the steps taken to bolster a predictable space operational environment and economic competitiveness. Ultimately, in order to achieve American excellence and leadership, a ‘closed loop’ on the policy system is needed, to gauge regularly and systematically whether the US is achieving the desired national outcomes.  相似文献   

11.
Space Policy is here reprinting edited extracts from two reports — one French, one American — which aim to forecast the market for space applications and launch services over the next 10 and 15 years respectively. Euroconsult 1986 edition of The World Space Industry Survey: Ten-Year Outlook gives a country-by-country analysis of policies and programmes; an evaluation of markets for space applications and a forecast of the market for launch systems. The Report on the 1986 Outside Users Payload Model, prepared by Battelle, Columbus Division, for the US National Aeronautics and Space Administration, provides an estimate of demand for launch services for payloads in a range of mission categories flown by countries outside the Soviet bloc. Using different starting points and methodologies, the two reports nevertheless draw convincingly similar conclusions.  相似文献   

12.
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   

13.
《Acta Astronautica》2009,64(11-12):1312-1317
This paper attempts to search the lost fragments from the near-synchronous US TitanIIIC transtage explosion of February 21, 1992, known as the second major fragmentation of a TitanIIIC transtage. This breakup was accidentally observed by the Maui GEODSS sensor, and then a total of 23 objects were reported from the breakup, no orbital data on any fragments has been generated by the SSN. In order to evaluate the debris cloud orbital evolution, we demonstrate the actual US TitanIIIC transtage explosion by using breakup model and orbit propagator. The perturbing accelerations, considered in this analysis are the non-spherical part of the Earth's gravitational attraction, the gravitational attraction due to the Sun and Moon, and the solar radiation pressure effects. Finally, we will present a search strategy based on distribution of the right ascension of the ascending node about the catalogued objects and the debris particles from the US TitanIIIC transtage explosion.  相似文献   

14.
The export market for space technology, goods and services is still in its infancy, but trends indicate definite economic growth in prospect. Private companies are increasingly keen to find a foothold or increase their share in the ever widening market. National goverments are undertaking a variety of measures to help and encourage them in the export of space technology. Competition for the older US producers is sharpening from foreign firms. Political conflict is arising based on this competition and on the potential dual use of some space technologies for civilian and military purposes. The main Western industrialized countries have recently agreed on common Guidelines to control the export of launcher technology that could be used for delivering nuclear weapons. The ‘Guidelines for Sensitive Missile-Relevant Transfer’ will affect the export of much space technology and equipment.  相似文献   

15.
This paper attempts to search the lost fragments from the near-synchronous US TitanIIIC transtage explosion of February 21, 1992, known as the second major fragmentation of a TitanIIIC transtage. This breakup was accidentally observed by the Maui GEODSS sensor, and then a total of 23 objects were reported from the breakup, no orbital data on any fragments has been generated by the SSN. In order to evaluate the debris cloud orbital evolution, we demonstrate the actual US TitanIIIC transtage explosion by using breakup model and orbit propagator. The perturbing accelerations, considered in this analysis are the non-spherical part of the Earth's gravitational attraction, the gravitational attraction due to the Sun and Moon, and the solar radiation pressure effects. Finally, we will present a search strategy based on distribution of the right ascension of the ascending node about the catalogued objects and the debris particles from the US TitanIIIC transtage explosion.  相似文献   

16.
会计的首要目标是为企业的经营决策提供有用的信息,会计信息公开是适应市场经济发展要求,顺应会计的国际化要求,符合内外部使用者的利益要求,同时也满足企业自身发展的要求的必然,会计信息公开制度的建立和完善是会计发展的趋势,尽管存在着多方面的不足,更多的是需要我们去发现和解决问题,完善和规范我国的会计体系。本文主要从两方面入手:一是确保企业公开的会计信息真实、可靠,前几个途径正是从这点入手的;二是投资者必须能识别和使用会计信息。  相似文献   

17.
会计的首要目标是为企业的经营决策提供有用的信息,会计信息公开是适应市场经济发展要求,顺应会计的国际化要求,符合内外部使用者的利益要求,同时也满足企业自身发展的要求的必然,会计信息公开制度的建立和完善是会计发展的趋势,尽管存在着多方面的不足,更多的是需要我们去发现和解决问题,完善和规范我国的会计体系。本文主要从两方面入手...  相似文献   

18.
Rather than aiming at overall preemenence in space, as in the past, it is important for the USA now to specify goals and objectives for its space programme. In the space transportation market, the USA faces long-term competition. Planned properly, the Space Shuttle, Space Station and transfer stages can be used as a unique transport system, forcing other suppliers to compete on US terms. Such a total transport service system could also include ELV support. In entering into international space agreements, the government must take into account the objective of maintaining the competitiveness of the US commercial sector.  相似文献   

19.
This paper discusses whether current international and national regulation of remote sensing activities achieves a true balance between proprietary interests of producers of remote sensing data and information and the needs of the community in accessing that data and information. By subjecting remote sensing data to general copyright restrictions that are often coupled with exclusive licences, irrespective of type or use of data and/or information, the development of important secondary information markets could be negatively hampered. In the long run, over-regulating access to space data may prove counter-productive in the information age. Using examples of different modes of information dissemination currently being practised, the paper highlights the balances to be drawn between legal issues of private ownership of data and information and public good interests. It concludes with suggestions for a more coherent regulatory approach.  相似文献   

20.
针对可见光和SAR图像融合,提出了一种基于跨模态差分感知和注意力机制的交互融合(TDPAM Fusion)算法,能有效保留可见光图像中的纹理结构和SAR图像的细节信息。首先,采用跨模态差分感知融合(Cross-Modal Differential Perception Fusion,CMDAF)模块提取图像的互补信息,避免真值缺失并提高融合精度。其次,通过坐标注意力机制(Coordinate Attention,CA)提高特征提取的准确性和效率,增强语义信息的集成。最后通过交互融合算法(Interactive Fusion Module,IFM)将特征自适应融合。设计了相应的大型基准数据集,用于网络模型的训练和测试。实验结果表明:TDPAM Fusion融合算法可以获得包含清晰SAR信息的高质量可见光图像。此外,融合算法将互信息(Mutual Information,MI)、空间频率(Spatial Frequency,SF)、视觉保真度(Visual Fidelity,VIF)和相关系数(Correlation Coefficient,CC)等关键指标,分别提高了约6.41%、10.36%、14.25%和4.74%。  相似文献   

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