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排序方式: 共有133条查询结果,搜索用时 46 毫秒
1.
徐忠  娄昭 《世界地理研究》2004,13(3):25-29,49
当前,世界政治形势处于动荡催生调整,调整蕴含机遇,在单极与多极矛盾的碰撞与互动中,正在形成某种更有效的机制,培育更为成熟、理性竞争的意识,促使各主要大国为世界的持久和平与繁荣共同担负起应有的责任。因此,国家经济安全是世界各国都普遍关注的战略问题。本文首先总结了就当今世界政治发展的四个特点,并在分析国际形势新变化对中国经济安全影响的基础上,提出了维护我国经济安全的六点思考。  相似文献   
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李勇 《天文学报》2007,48(2):256-268
“干支回推法”是针对中国历史时期所特有的干支材料而设计的新天文年代学方法.以一组假设的材料为例,系统地给出了该方法的完整求解过程.指出该方法的优势在于准确高效,能有效地处理某些年代学难题.此外,除材料的公历日期外还能将当时的历法细节一同迭代解出.  相似文献   
4.
通过分析哲学和地图本质特征之间的关联,探讨了地图的哲学内涵及其在实现地图目的中起到的作用,尝试在通过地图认识世界、改造世界的探索道路上寻根溯源,从强化根基的角度使地图在新时代发挥更大的作用。  相似文献   
5.
Hoyt & Schatten (1998) claim that Simon Marius would have observed the sun from 1617 Jun 7 to 1618 Dec 31 (Gregorian calendar) all days, except three short gaps in 1618, but would never have detected a sunspot – based on a quotation from Marius in Wolf (1857), but mis‐interpreted by Hoyt & Schatten. Marius himself specified in early 1619 that for one and a half year... rather few or more often no spots could be detected... which was never observed before (Marius 1619). The generic statement by Marius can be interpreted such that the active day fraction was below 0.5 (but not zero) from fall 1617 to spring 1619 and that it was 1 before fall 1617 (since August 1611). Hoyt & Schatten cite Zinner (1952), who referred to Zinner (1942), where observing dates by Marius since 1611 are given but which were not used by Hoyt & Schatten. We present all relevant texts from Marius where he clearly stated that he observed many spots in different form on and since 1611 Aug 3 (Julian) = Aug 13 (Greg.) (on the first day together with Ahasverus Schmidnerus); 14 spots on 1612 May 30 (Julian) = Jun 9 (Greg.), which is consistent with drawings by Galilei and Jungius for that day, the latter is shown here for the first time; at least one spot on 1611 Oct 3 and/or 11 (Julian), i.e. Oct 13 and/or 21 (Greg.), when he changed his sunspot observing technique; he also mentioned that he has drawn sunspots for 1611 Nov 17 (Julian) = Nov 27 (Greg.); in addition to those clearly datable detections, there is evidence in the texts for regular observations. For all the information that can be compared to other observers, the data from Marius could be confirmed, so that his texts are highly credible. We also correct several shortcomings or apparent errors in the database by Hoyt & Schatten (1998) regarding 1612 (Harriot), 1615 (Saxonius, Tard´e), 1616 (Tard´e), 1617–1619 (Marius, Riccioli/Argoli), and Malapert (for 1618, 1620, and 1621). Furthermore, Schmidnerus, Cysat, David & Johann Fabricius, Tanner, Perovius, Argoli, and Wely are not mentioned as observers for 1611, 1612, 1618, 1620, and 1621 in Hoyt & Schatten. Marius and Schmidnerus are among the earliest datable telescopic sunspot observers (1611 Aug 3, Julian), namely after Harriot, the two Fabricius (father and son), Scheiner, and Cysat. Sunspots records by Malapert from 1618 to 1621 show that the last low‐latitude spot was seen in Dec 1620, while the first high‐latitude spots were noticed in June and Oct 1620, so that the Schwabe cycle turnover (minimum) took place around that time, which is also consistent with the sunspot trend mentioned by Marius and with naked‐eye spots and likely true aurorae. We consider discrepancies in the Hoyt & Schatten (1998) systematics, we compile the active day fractions for the 1610s, and we critically discuss very recent publications on Marius which include the following Maunder Minimum. Our work should be seen as a call to go back to the historical sources. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
6.
张旗 《甘肃地质》2022,(1):1-11
突现论是一个崭新的哲学理论,只有100多年的历史,但是,突现论已经崛起为复杂性系统的核心理论,成为近期哲学领域研究的热点之一。突现论认为,世界是由不同层级(或层次)构成的,不同层次按照事物的复杂程度不断提高划分的。世界基本上有三大层次,从低到高为物理、生命和心灵。突现论有4个特征:1,不同层次性质不同,高层次性质来源于低层次;2,突现具有不可预测的新颖性;3,不可还原性;4,高低层次之间存在因果关系。文中简要介绍了突现论的概念并探讨了突现论在变质岩、岩浆岩、矿床学以及地球演化研究中的可能的应用,希望能够对科学研究的进一步发展有利。  相似文献   
7.
Most of our knowledge about the Sun's activity cycle arises from sunspot observations over the last centuries since telescopes have been used for astronomy. The German astronomer Gustav Spörer observed almost daily the Sun from 1861 until the beginning of 1894 and assembled a 33‐year collection of sunspot data covering a total of 445 solar rotation periods. These sunspot drawings were carefully placed on an equidistant grid of heliographic longitude and latitude for each rotation period, which were then copied to copper plates for a lithographic reproduction of the drawings in astronomical journals. In this article, we describe in detail the process of capturing these data as digital images, correcting for various effects of the aging print materials, and preparing the data for contemporary scientific analysis based on advanced image processing techniques. With the processed data we create a butterfly diagram aggregating sunspot areas, and we present methods to measure the size of sunspots (umbra and penumbra) and to determine tilt angles of active regions. A probability density function of the sunspot area is computed, which conforms to contemporary data after rescaling. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
8.
The strong 14C increase in the year AD 774/5 detected in one German and two Japanese trees was recently suggested to have been caused by an impact of a comet onto Earth and a deposition of large amounts of 14C into the atmosphere (Liu et al. 2014). The authors supported their claim using a report of a historic Chinese observation of a comet ostensibly colliding with Earth's atmosphere in AD 773 January. We show here that the Chinese text presented by those authors is not an original historic text, but that it is comprised of several different sources. Moreover, the translation presented in Liu et al. is misleading and inaccurate. We give the exact Chinese wordings and our English translations. According to the original sources, the Chinese observed a comet in mid January 773, but they report neither a collision nor a large coma, just a long tail. Also, there is no report in any of the source texts about “dust rain in the daytime” as claimed by Liu et al. (2014), but simply a normal dust storm. Ho (1962) reports sightings of this comet in China on AD 773 Jan 15 and/or 17 and in Japan on AD 773 Jan 20 (Ho 1962). At the relevant historic time, the Chinese held that comets were produced within the Earth's atmosphere, so that it would have been impossible for them to report a “collision” of a comet with Earth's atmosphere. The translation and conclusions made by Liu et al. (2014) are not supported by the historical record. Therefore, postulating a sudden increase in 14C in corals off the Chinese coast precisely in mid January 773 (Liu et al. 2014) is not justified given just the 230Th dating for AD 783 ± 14. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
9.
BOOK REVIEWS     
Books reviewed in this article: Aerial Photography and Remote Sensing Aerial photography and image interpretation for Resource Management . DAVID P. PAINE . Analytical Models and Techniques Spatial Processes Models and Applications A. D. CLIFF AND J. K. ORD Quantitative and Statistical Approaches to Geography: A Practical Manual JOHN A. MATTHEWS . Cartography and Maps Map Data Processing . HERBERT FREEMAN AND GOFFREDO G. PIERONI , eds. Computer-assisted Cartography: Principles and Prospects, 1982 . MARK S. MONMONIER . Cultural Navajo Architecture: Forms, History, Distributions . STEPHEN C. JETT AND VIRGINIA E . SPENCER . Rational Landscapes and Humanistic Geography . EDWARD RELPH . Economic The Structure and Control of a State Economy . W. L. L'ESPERANCE . Economic Geography . JAMES O. WHEELER AND PETER O. MULLER . The Myth of the Family Farm: Agribusiness Dominance of U.S. Agriculture . INGOLF VOCELER . Libya: The Experience of Oil . J. A. ALLEN . Geography of Public Finance, Welfare Under Fiscal Federalism and local Government Finance . ROBERT BENNETT . Environmental Management, Resources, and Systems Mountains and Man . LARRY W. PRICE . Environmental Geology . DONALD R. COATES . An Introduction to Environmental Systems . G. H. DURY . The Environment: Chinese and American Views . Edited by LAURENCE J. C. MA AND ALLEN G. NOBLE . Land Use in America . RICHARD H. JACKSON . Medical Conceptual and Methodological Issues in Medical Geography . MELINDA S. MEADE (ed.). Philosophy and Geographic Thought Birds in Egg/Eggs in Bird . GUNNAR OLSSON . PhysicaI Climatology: Selected Applications . J. E. OLIVER . Geomorphological Techniques . ANDREW GOUDIE (ed.). Political Politics, Geography and Behaviour . RICHARD MUIR AND RONAN PADDISON . The State of the World Atlas . MICHAEL KIDRON AND RONALD SECAL . Population The Population of the South . DUDLEY L. POSTON , JR . AND ROBERT H. WELLER , eds. Regional Latin America: Economic Development and Regional Differentiation . ARTHUR MORRIS . Developing the Amazon . EMILIO F. MORAN . Western Europe: A Systematic Human Geography . BRIAN W. ILBERY . Settlement Systems in Sparsely Settled Regions: The United States and Australia . RICHARD E. LONSDALEAND JOHN H. HOLMES , eds. African Perspectives: The Economic Geography of Nine African States . HARM DE BUJ AND ESMOND MARTIN , eds. Rural Nonmetropolitan America in Transition . AMOS H. HAWLEY AND SARA MILLS MAZIE , eds. Social Crime and Environment . R. NORMAN DAVIDSON . The Ghetto: Readings with Interpretations . JOE T. DARDEN , ed. Urban Urban Problems and Planning in the Developed World . MICHAEL PACIONE (ed.) Problems and Planning in Third World Cities . Edited by MICHAEL PACIONE . The City in West Europe . D. BURTENSHAW , M. BATEMAN , AND C. J. ASHWORTH .  相似文献   
10.
BOOK REVIEWS     
Books reviewed in this article: Aerial Photography and Remote Sensing. Terrain Analysis and Remote Sensing . JOHN R. G. TOWNSHEND , ed. Environmental Data Use in Computer-assisted Data Handling Systems: The Results of a Survey of Applications in the Pacific Northwest States . KENNETH E. GORDON . Applied Land Use: A Spatial Approach . JOHN F. LOUNSBURY , LAWRENCE M. SOMMERS , AND EDWARD A. FERNALD , eds. The Second Battle of New Orleans: A History of the Vieux Carre Riverfront-Expressway Controversy . RICHARD O. BAUMBACH , JR. AND WILLIAM E. BORAH . Cultural Environmental Archaeology . MYRA SHACKLEY . The Immoral landscape: Female Prostitution in Western Societies . RICHARD SYMANSKI . life Among the Poor in Cairo . UNNI WIKAN , translated by Ann Henning. Women, Work and Property in Northwest India . URSULA SHARMA . The Domestication of Women: Discrimination in Developing Societies . BARBARA ROGERS Economic Optimization in Locational and Transport Analysis . A. G. WILSON , J. D. COELHO , S. M. MACGILL , H. C. W. L. WILLIAMS . New Tools for Economic Development: The Enterprise Zone, Development Bank, and RFC . GEORGE STERNLIEB AND DAVID LISTOKIN , eds. Regional Wage Inflation . R. L. MARTIN , ed. Finding A Place For Energy-Siting Coal Conversion Facilities . FRANK J. CALZONETTI WITH MARK S. ECKERT . Environmental Management, Resources, and Systems Environmentalism. Second Edition . T. O'RIORDAN . Countryside Conservation . BRYN GREEN . Medical Spatial Diffusion: An Historical Geography of Epidemics in an Island Community . A. D. CLIFF , P. HAGGETT , J. K. ORD , AND G. R. VERSEY . Philosophy and Geographic Thought Order and Skepticism: Human Geography and the Dialectic of Science . RICHARD SZYMANSKI AND JOHN A. AGNEW . Measurement of Subjective Phenomena . D. F. JOHNSTON , ed. Conceptions of Space in Social Thought: A Geographic Perspective . ROBERT DAVID SACK . The Association of American Geographers: The First Seventy-five Years: 1904-1979 . PRESTON E. JAMES AND GEOFFREY J. MARTIN . The Life and Thought of Isaiah Bowman . GEOFFREY J. MARTIN . Physical River Basin Planning: Theory and Practice . SURANJIT K. SAHA AND CHRISTOPHER J. BARROW , eds. Soils and landforms: An Integration of Ceomorphology and Pedology . A. I. GERRARD Climatic Change and Society. Consequences of Increasing Atmospheric Carbon Dioxide . WILLIAM W. KELLOGG AND ROBERT SCHWARE . Political Political Redistrictings and Geographic Theory . RICHARD L. MORRILL . Population Studies in Spanish American Population History: Dell Plain Latin American Studies NO. 8 . DAVID J. ROBINSON , ed. Population Redistribution in the Midwest . CURTIS C. ROSEMAN , ANDREW J. SOFRANKO , AND JAMES D. WILLIAMS , eds. Geographical Perspectives on the Elderly . A. M. WARNES , ed. Regional Perspective On the American South . MERLE BLACK AND JOHN SHELTON REED , eds. The Prairies and Plains: Prospects for the 80s . JOHN R. ROGGE , ed. Rural Rural Settlement in an Urban World . MICHAEL BUNCE . Social Accident at Three Mile Island: The Human Dimensions . DAVID L. SILLS , C. P. WOLF , AND VIVIEN B. SHELANSKI , eds. The American Small Town: Twentieth-Century Place Images . JOHN JAKLE . Urban A House of My Own . SUSAN LOBO . The City: Patterns and Processes in the Urban Ecosystem . CHRISTOPHER H. EXLINE , GARY L. PETERS , AND ROBERT P. LARKIN . Movement in Cities . P. W. DANIELS AND A. M. WARNES . Urbanization and Urban Planning in Capitalist Society . MICHAEL DEAR AND ALLEN J. SCOT , eds.  相似文献   
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