Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences最新文献_第2页

Heterogeneous nucleation and adsorption 非均相成核和吸附

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-03-15 DOI: 10.1098/rsta.2002.1137

B. Cantor

引用次数: 86

Control of nucleation in glass ceramics 玻璃陶瓷成核的控制

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-03-15 DOI: 10.1098/rsta.2002.1152

W. Höland, V. Rheinberger, M. Schweiger

引用次数: 149

Prediction of the 2001 Leonid activity and an assessment of the spacecraft impact hazard 2001年狮子座流星雨活动的预测和航天器撞击危险的评估

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-01-15 DOI: 10.1098/rsta.2002.1120

Michael Müller, N. Mcbride, S. Green, J. Zarnecki

{"title":"Prediction of the 2001 Leonid activity and an assessment of the spacecraft impact hazard","authors":"Michael Müller, N. Mcbride, S. Green, J. Zarnecki","doi":"10.1098/rsta.2002.1120","DOIUrl":"https://doi.org/10.1098/rsta.2002.1120","url":null,"abstract":"Different maxima in the Leonid activity observed in the same year can be identified as due to dust particles ejected during different perihelion passages of the parent comet, 55P/Tempel–Tuttle. This is because the ecliptic intersections of trajectories of particles that were ejected during different comet apparitions lie well separated in the ecliptic plane. For November 2001, we determine the ecliptic intersection points of particles originating from various apparitions of 55P/Tempel–Tuttle and thus predict the times of maximum Leonid activity. By comparing this year's configuration with the past, we also give an estimate of the flux that might be expected in 2001. As light flashes due to Leonid impacts on the Moon can be detected on Earth, we give the times of closest approaches of dust trails to the Moon. By comparing the predicted Leonid meteoroid flux on the Earth's atmosphere with the flux of sporadic meteoroids, we estimate that the hazard of a Leonid impact on a spacecraft in low–Earth orbit is low. However, the densest part of the Leonid trails will not reach Earth, but will cross the geo–stationary orbit (GEO) ring. The impact risk will reach its maximum for GEO satellites at longitudes between 35° and 160° W between 17.00 and 20.00 UT on 18 November 2001. While the overall risk of major damage is still relatively low, this period undoubtedly represents the greatest impact risk to spacecraft since the beginning of the space–age.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":"3 1","pages":"175 - 179"},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79919304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Autonomy, control, processing and dissemination: getting data to the scientists, affordably 自主、控制、处理和传播:以低廉的价格将数据提供给科学家

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-01-15 DOI: 10.1098/rsta.2002.1121

P. Norris

{"title":"Autonomy, control, processing and dissemination: getting data to the scientists, affordably","authors":"P. Norris","doi":"10.1098/rsta.2002.1121","DOIUrl":"https://doi.org/10.1098/rsta.2002.1121","url":null,"abstract":"A clear distinction is usually appropriate between the technologies and development processes for space–borne and ground–based functions. Limitations in the performance of space–borne computing, storage and dissemination facilities often preclude the use of non–space software technology. The key to affordability is the creation of international standards so that despite relatively high development costs, solutions can be reused across many missions and organizations. By contrast, ground–based functions can benefit from products developed for non–space applications. The challenge is to create an architecture that benefits from existing technology and meets the mission requirements. Optimizing the organizational arrangements for space missions is perhaps where the greatest savings can be made. A management structure that ensures that end users dominate the establishment of requirements leads to more affordable missions than one that is, say, technology driven. Industry implementation teams must include expertise in the scientific disciplines and mission objectives to ensure success. Geostationary–weather–satellite, space–science and satellite–navigation missions are used to illustrate these issues.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":"15 1","pages":"183 - 192"},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79712760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Orbital debris: a growing threat to space operations 轨道碎片:对太空运行的日益严重的威胁

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-01-15 DOI: 10.1098/rsta.2002.1118

R. Crowther

引用次数: 17

Space plasma influences on the Earth's atmosphere 空间等离子体对地球大气层的影响

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-01-15 DOI: 10.1098/rsta.2002.1114

Neil Arnold

引用次数: 1

A novel method for achieving SAR imaging by means of a microsatellite constellation 利用微卫星星座实现SAR成像的新方法

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-01-15 DOI: 10.1098/rsta.2002.1106

O. S. Mitchell, C. Underwood

{"title":"A novel method for achieving SAR imaging by means of a microsatellite constellation","authors":"O. S. Mitchell, C. Underwood","doi":"10.1098/rsta.2002.1106","DOIUrl":"https://doi.org/10.1098/rsta.2002.1106","url":null,"abstract":"The current emphasis in the satellite industry is on replacing large satellite platforms with one or more smaller satellites, built at lower cost, yet able to accomplish similar mission objectives. However, it is recognized that such small satellites pose severe constraints on payload volume, mass and power. Thus, the power constraint of synthetic–aperture–radar (SAR) imaging is such that a microsatellite would seem inappropriate. The primary reason for the high–transmit–power requirement is that traditional SAR systems collect the backscatter. Thus, if the forward–scattered element is collected, then the resultant reduction in transmit–power could make it feasible for installation on a microsatellite. Based upon this principle, a novel method by which two microsatellites ‘fly’ in a specific formation to accomplish an SAR imaging mission, bistatically, is proposed. The satellites view a swath of 30 km (chosen to limit the amount of data), at a ground resolution of 30 m, from an altitude of 700 km. The transmitting satellite will be the ‘master’, with the receiver satellite ‘slaved’ off it for synchronization. Applications to a polar–ice–monitoring mission are discussed.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":"1 1","pages":"45 - 49"},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75925891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of magnetometer data using wavelet transforms 用小波变换分析磁强计数据

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-01-15 DOI: 10.1098/rsta.2002.1115

J. M. Rees, Christopher R. Wilford, R. Moffett, Z. Dent, I. Mann

引用次数: 4

In-orbit results from the SNAP-1 nanosatellite and its future potential SNAP-1纳米卫星的在轨结果及其未来潜力

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-01-15 DOI: 10.1098/rsta.2002.1123

C. Underwood, G. Richardson, J. Savignol

{"title":"In-orbit results from the SNAP-1 nanosatellite and its future potential","authors":"C. Underwood, G. Richardson, J. Savignol","doi":"10.1098/rsta.2002.1123","DOIUrl":"https://doi.org/10.1098/rsta.2002.1123","url":null,"abstract":"It is now feasible to construct highly capable ‘nanosatellites’ (i.e. sub–10 kg satellites) to provide cost–effective and rapid–response orbiting test vehicles for advanced space missions and technologies. The UK's first nanosatellite, SNAP–1—designed and built by Surrey Space Centre (SSC) and Surrey Satellite Technology Ltd (SSTL) staff — is an example of such a test vehicle: in this case, built with the primary objective of demonstrating that a sophisticated, fully agile nanosatellite can be constructed rapidly, and at very low cost, using an extension of the modular–COTS–based design philosophy pioneered by SSC for its microsatellites. SNAP–1 was successfully launched into orbit on 28 June 2000 from the Plesetsk Cosmodrome on board a Russian Cosmos rocket. It flew alongside a Russian Cospas–Sarsat satellite called Nadezhda, and an SSTL–built Chinese microsatellite, called Tsinghua–1. The first year of operations has been highly successful, with SNAP–1 becoming the first nanosatellite to have demonstrated full attitude and orbit control, via its miniature momentum–wheel–based attitude control system and its butane–propellant–based propulsion system. This paper reviews the initial results of the SNAP–1 mission.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":"4 1","pages":"199 - 203"},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88807228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 33

Solar–wind–magnetosphere–ionosphere interactions in the Earth's plasma environment 地球等离子体环境中的太阳风-磁层-电离层相互作用

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences Pub Date : 2003-01-15 DOI: 10.1098/rsta.2002.1112

S. Cowley, J. Davies, A. Grocott, H. Khan, M. Lester, K. McWilliams, S. Milan, G. Provan, P. Sandholt, J. Wild, T. Yeoman

引用次数: 30