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31.
从教学理论和课程模式方面对英语教学的后发优势进行研究,并详细探讨了后发优势对大学英语教学和学生语言交际能力提高的影响.一切从实际出发,发挥后发优势能促进教学各方面的创新和跨越式发展.  相似文献   
32.
BOOK REVIEWS     
Book Reviewed in this article: Main Street: Northeastern Oregon: The Founding and Development of Small Towns . Barbara Ruth Bailey . Food Politics: The Regional Conflict . David N. Balaam and Michael J. Carey , eds. The International Economy and Industrial Development: Trade and Investment in the Third World . R. Ballance , J. Ansari and H. Singer . Neighborhoods in Urban America . Ronald H. Bayor , ed. The English Heartland . By Robert Beckinsale and Monica Beckinsale . Regional Dimensions of Industrial Policy . Michael E. Bell and Paul S. Lande , eds. Tension Areas of the World . D. Gordon Bennett , ed. Latin America: an Introductory Survey . B. W. Blouet and O. M. Blouet , eds. Integration and Division: Geographical Perspectives on the Northern Ireland Problem . Frederick W. Boal and J. Neville H. Douglas , eds. Energy and Land Use . Robert W. Burchell and David Listokin , eds. Slopes and Weathering . Michael Clarke and John Small . Alaska's Rural Development . Peter G. Cornwall and Gerald Mc Beath , eds. The Politics of Park Design: A History of Urban Parks in America . Galen Cranz . World Congress on Land Policy, 1980, Proceedings . Matthew Cullen and Sharon Woolery , eds. Oregon Divided: A Regional Geography . Samuel N. Dicken and Emily F. Dicken . Urban Food Marketing and Third World Rural Development . T. Scarlett Epstein . South Africa: Spatial Frameworks for Development . T. J. D. Fair . Institutions and Geographical Patterns . Robin Flowerdew , ed. Industrialization of U.S. Agriculture, An Interpretive Atlas . Howard F. Gregor . Planning Theory: Prospects for the 1980s . Patsy Healy , Glen Mc Dougall and Michael J. Thomas , eds. Neighborhood Mobilization: Redevelopment and Response . Jeffrey R. Henig . The American Urban System: A Geographical Perspective . R. J. Johnston . Climate, History and the Modern World . Hubert H. Lamb . Climate and History: Studies in Past Climates and Their Impact on Man . T. M. L. Wigley , M. J. Ingram and G. Farmer . China: Railways and Agricultural Development, 1875–1935 . Ernest P. Liang . A Desirable Energy Future—A National Perspective . Robert S. Livingston , T. D. Anderson , T. M. Besmann , M. Olszewski , A. M. Perry , and C. D. West . Topothesia: Essays Presented to T. S. Ó Máille . B. S. Mac Aodha , ed. Transportation for the Poor: Research in Rural Mobility . Hal S. Maggied . Land Uses in American Cities . Harold M. Mayer and Charles R. Haves . Industrial Organisation and Location . Philip Mc Dermott and Michael Taylor . Human Adaptability: an Introduction to Ecological Anthropology . Emilio F. Moran . Regional Analysis and the New International Division of Labor . Frank Moulaert and Patricia W. Salinas , eds. The Nuclear War Atlas. Victoriaville, Quebec, Canada : Urbanization and Environmental Quality . Isao Orishimo . The Garden of Eden: The Botanic Garden and the Re-Creation of Paradise . John Prest . Earthfire, The Eruption of Mount St. Helens . Charles Rosenfeld and Robert Cooke . Contest for the South China Sea . Marwyn S. Samuels . The Future of the Wetlands: Assessing Visual-Cultural Values . Richard C. Smardon , ed. Tucson: the Life and Times of An American City. C. L. Sonnichsen . The Geography of Multinationals . Michael Taylor and Nigel Thrift , eds. Impact of Marine Pollution on Society . Virginia Tippie and Dana Kester . Reviving the Industrial City: the Politics of Urban Renewal in Lyon and Birmingham . Jerry A. Webman . Andean Reflections: Letters from Carl O. Sauer While on a South American Trip under a Grant from the Rockefeller Foundation, 1942 . Robert C. West , ed. Cartographic Drawing with Computers . P. Yoeli .  相似文献   
33.
马丽  龚忠杰  许堞 《地理科学进展》2022,41(9):1579-1591
粤港澳大湾区作为中国实施“双循环”战略、产业转型升级的先行区,将产业创新与产业优势有效融合才能实现产业的高质量发展。论文运用偏离—份额分析法、耦合协调度模型对粤港澳大湾区地级城市单元2000—2020年工业各行业的创新优势与产业优势的时空匹配关系进行研究,并重点关注了珠三角9市与港澳创新联系和产业优势的关系。研究发现:大湾区各城市创新的工业行业分布格局虽然不同,但均呈现向计算机通信和其他电子设备制造、仪器仪表制造等行业集中的趋势;同时各地市在计算机通信和其他电子设备制造、通用设备制造、专用设备制造、仪器仪表制造等行业具有产业优势,且与创新的融合度较高,但在交通运输设备制造、化学原料制品、纺织等优势行业的创新融合度较低;珠三角城市与港澳地区的创新联系不断加强,尤以广州、深圳两市的联系强度最高。最后,从促进大湾区融合创新、产创协同的角度提出政策建议。研究从实证角度为理解产业链创新链融合的空间和部门属性提供了理论与现实依据。  相似文献   
34.
Book Reviewed in this article:

Main Street: Northeastern Oregon: The Founding and Development of Small Towns. Barbara Ruth Bailey.

Food Politics: The Regional Conflict. David N. Balaam and Michael J. Carey, eds.

The International Economy and Industrial Development: Trade and Investment in the Third World. R. Ballance, J. Ansari and H. Singer.

Neighborhoods in Urban America. Ronald H. Bayor, ed.

The English Heartland. By Robert Beckinsale and Monica Beckinsale.

Regional Dimensions of Industrial Policy. Michael E. Bell and Paul S. Lande, eds.

Tension Areas of the World. D. Gordon Bennett, ed.

Latin America: an Introductory Survey. B. W. Blouet and O. M. Blouet, eds.

Integration and Division: Geographical Perspectives on the Northern Ireland Problem. Frederick W. Boal and J. Neville H. Douglas, eds.

Energy and Land Use. Robert W. Burchell and David Listokin, eds.

Slopes and Weathering. Michael Clarke and John Small.

Alaska's Rural Development. Peter G. Cornwall and Gerald McBeath, eds.

The Politics of Park Design: A History of Urban Parks in America. Galen Cranz.

World Congress on Land Policy, 1980, Proceedings. Matthew Cullen and Sharon Woolery, eds.

Oregon Divided: A Regional Geography. Samuel N. Dicken and Emily F. Dicken.

Urban Food Marketing and Third World Rural Development. T. Scarlett Epstein.

South Africa: Spatial Frameworks for Development. T. J. D. Fair.

Institutions and Geographical Patterns. Robin Flowerdew, ed.

Industrialization of U.S. Agriculture, An Interpretive Atlas. Howard F. Gregor.

Planning Theory: Prospects for the 1980s. Patsy Healy, Glen McDougall and Michael J. Thomas, eds.

Neighborhood Mobilization: Redevelopment and Response. Jeffrey R. Henig.

The American Urban System: A Geographical Perspective. R. J. Johnston.

Climate, History and the Modern World. Hubert H. Lamb.

Climate and History: Studies in Past Climates and Their Impact on Man. T. M. L. Wigley, M. J. Ingram and G. Farmer.

China: Railways and Agricultural Development, 1875–1935. Ernest P. Liang.

A Desirable Energy Future—A National Perspective. Robert S. Livingston, T. D. Anderson, T. M. Besmann, M. Olszewski, A. M. Perry, and C. D. West.

Topothesia: Essays Presented to T. S. Ó Máille. B. S. Mac Aodha, ed.

Transportation for the Poor: Research in Rural Mobility. Hal S. Maggied.

Land Uses in American Cities. Harold M. Mayer and Charles R. Haves.

Industrial Organisation and Location. Philip McDermott and Michael Taylor.

Human Adaptability: an Introduction to Ecological Anthropology. Emilio F. Moran.

Regional Analysis and the New International Division of Labor. Frank Moulaert and Patricia W. Salinas, eds.

The Nuclear War Atlas. Victoriaville, Quebec, Canada:

Urbanization and Environmental Quality. Isao Orishimo.

The Garden of Eden: The Botanic Garden and the Re-Creation of Paradise. John Prest.

Earthfire, The Eruption of Mount St. Helens. Charles Rosenfeld and Robert Cooke.

Contest for the South China Sea. Marwyn S. Samuels.

The Future of the Wetlands: Assessing Visual-Cultural Values. Richard C. Smardon, ed.

Tucson: the Life and Times of An American City. C. L. Sonnichsen.

The Geography of Multinationals. Michael Taylor and Nigel Thrift, eds.

Impact of Marine Pollution on Society. Virginia Tippie and Dana Kester.

Reviving the Industrial City: the Politics of Urban Renewal in Lyon and Birmingham. Jerry A. Webman.

Andean Reflections: Letters from Carl O. Sauer While on a South American Trip under a Grant from the Rockefeller Foundation, 1942. Robert C. West, ed.

Cartographic Drawing with Computers. P. Yoeli.  相似文献   
35.
地理国情普查是一项全新的事业,许多环节和方法需要探索和研究。随着云计算技术的发展和广泛应用,在云计算支持下利用云平台开展地理国情普查十分必要。但在云计算环境下,数据存放导致可信度和信任边界受到质疑,面临着合规检查和存放位置风险及数据公开运行、未被有效隔离引来的风险等诸多挑战。云计算在安全性方面具有信誉信用、数据同构、运行管理、网络容灾等独特优势,以及数据安全、高可用性能力、安全人才等深层次优势。当然,将云计算理念和方法引入地理国情普查要有一个过程,许多问题需要探讨和解决。相信随着各项技术的进步,云计算将会更好地服务于地理国情普查监测工作。  相似文献   
36.
Large numbers of rotifer eggs from sediment resting egg banks may hatch simultaneously under appropriate conditions;therefore,natural populations are likely to be multiclonal in a growing season.A recent field investigation showed that subordinate and ephemeral clones were able to establish populations in an environment with several strongly dominant clone populations.However,it was not clear how the subordinate populations maintained their growth under these conditions where the crowding signal would induce high levels of sexual reproduction in the dominant clone populations.In the present study,we conducted a continuous passage to 60 generations for new populations at three different temperatures(15°C,25°C,and 35°C).These populations emerged from resting eggs produced by a clone population.At the first,30th,and 60th generations,the populations were sampled and fitness was assayed using the life-table method.We found a significant short-term fitness advantage for populations newly emerged from resting eggs produced by a clone population of the rotifer Brachionus calyciflorus,followed by a significant decrease in relative fitness with long-term continuous passage.Our results suggested that the early shortterm fitness advantage was important for later-hatched and subordinate clone populations in an environment with multiple sympatric clones.The early short-term fitness might also promote the coexistence of sympatric clones because it could help to offset the cost of early sexual reproduction.  相似文献   
37.
利用31a(1979—2009)气候月平均的海平面气压(SLP)资料,提出1种与北半球中高纬度环流转变相适应的分季法。并根据这个客观分季方法,通过SEOF分析,发现大气环流主模态的季节演变有着典型的北极涛动(AO)空间结构,其时间系数在1990年代中期发生转型。500hPa上纬向波的涡度有着南北反位相的分布特征,冬季正涡度的区域对应着气旋性环流,其覆盖范围广,而夏季正涡度区域更偏北,可见AO在冬季增强,夏季减弱。北半球SLP异常的EOF分解第一模态为北极涛动(AO),第二模态是偶极异常(DA);将这2个模态称之为北半球中高纬度大气环流异常的优势模态。通过计算优势模态与海冰面积的超前滞后相关性,发现AO依然是控制海冰变化的前期大气环流异常的模态,而DA则可能是海冰快速变化后期大气环流的主导模态。  相似文献   
38.
甘肃省水土资源空间分布与组合评价   总被引:3,自引:1,他引:2  
以甘肃省的四个区域:陇南区、甘南高原区、河西走廊区、陇东和陇中黄土高原区,根据其水土资源空间分布与组合的统一性、一致性、连续性,建立了与以往不同的数学模型,并用此模型对甘肃省四个区域水土资源的空间分布和组合进行量化分析、评价,并得出了各个区域水土资源总量的综合优势度并对其进行了对比、分析。在充分发挥四大区水土资源组合潜在价值,体现水土资源组合特色优势的前提下,利用综合优势度对四大区进行评价,为甘肃省经济可持续发展提供科学的参考。  相似文献   
39.
全液压动力头钻机的改进建议   总被引:2,自引:1,他引:1       下载免费PDF全文
通过对全液压动力头钻机的使用,肯定了其优越性。通过与立轴式钻机施工相对比,找出全液压钻机在实际应用中存在的不足和对其改进的建议。  相似文献   
40.
虚拟水战略优势度及其评价   总被引:3,自引:0,他引:3  
邹君  杨玉蓉  毛德华 《冰川冻土》2009,31(3):565-570
基于对虚拟水战略内涵以及虚拟水战略背景对我国不同区域经济社会发展影响认识上的差异,特提出虚拟水战略优势度的概念,用以量度区域虚拟水战略实施的适宜性以及虚拟水战略背景对区域经济社会生态等的影响程度.分析了虚拟水战略优势度的概念内涵及其影响因素,从水资源供给、非农水资源需求、水资源管理和农业发展4个方面构建了包含12个具体指标的综合定量评价指标体系,对我国31个省级行政区虚拟水战略优势度进行了定量评价.结果表明:我国虚拟水战略优势度存在显著的区域差异,而且,优势度等级存在"两头多,中间少"的结构特点和"东部高、西部低","南部和北部高、中间低"的带状空间分布规律.其中北方4省市和东南8省区优势度最大,是全球虚拟水战略背景对其影响最为深远的区域,也是我国虚拟水研究及虚拟水战略实践的关键区域.  相似文献   
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