金刚石绳索取心钻进施工效率影响因素分析

采用技术经济学研究方法,对一些影响金刚石绳索取心钻进施工效率的钻探技术指标,如机械钻速、回次长度、起下钻速度、起钻间隔进行了分析和评价。通过了解这些因素在不同钻孔深度条件下对钻进施工效率影响作用的大小,可为钻探项目的设备、器具和钻进工艺方法选择提供依据。     

BOOK REVIEWS

Book Reviewed in this article: Rabat: Urban Apartheid in Morocco . Janet Abu -Lughod . Marketplaces in a Developing Country: The Case of Western Nigeria . Isaac Ayinde Adalemo . Farming Development and Space: A World Agricultural Geography . Bernd Andreae . Section and Party: A Political Geography of American Presidential Elections, from Andrew Jackson to Ronald Reagan . J. Clark Archer and Peter J. Taylor . Women and Space: Ground Rules and Social Maps . Shirley Ardener , ed. European Progress in Spatial Analysis . R. J. Bennett , ed. The Origins of Academic Geography in the United States . Brian W. Blouet Geographic Perspectives on Global Problems . Ronald Reed Boyce . Seasonal Dimensions to Rural Poverty . Robert Chambers , Richard Longhurst and Arnold Pacey eds. The New Nationalism and the Use of Common Spaces: Issues in Marine Pollution and the Exploitation of Antarctica . Jonathan I. Charney , ed. Communications Tomorrow: The Coming of the Information Society . Edward Cornish , ed. The Design of Suburbia . Arthur Edwards . Explorer on the Northern Plains: Lieutenant Gouverneur K. Warren's Preliminary Report of Explorations in Nebraska and Dakota in the Years 1855–56–57. With an Introduction by Frank N. Schubert . The Changing Climate: Responses of the Natural Flora and Fauna . Michael J. Ford . Essentials of Physical Geography . Robert E. Gabler , Robert J. Sager , Sheila Brazier , and Daniel L. Wise. The Road to Jaramillo . William Glen . Valued Environments . John R. Gold and Jacquelin Burgess , eds. Proximity and Preference: Problems in the Multidimensional Analysis of Large Data Sets . Reginald G. Golledge and John N. Rayner , eds. A Search for Common Ground . Peter Gould and Gunnar Olsson , eds. Geography: Its History and Concepts . Arild Holt -Jensen . A Population Geography . Huw R. Jones . The Human Mosaic: A Thematic Introduction to Cultural Geography, 3rd ed. Terry G. Jordan and Lester Rowntree . Urban Social Geography: An Introduction . Paul Knox . The Anatomy of Job Loss: The How, Why and Where of Employment Decline . Doreen Massey and Richard Meegan . The Information Society as Post-Industial Society . Yoneji Masuda . Map Librarianship, 2nd ed. Harold Nichols . India: Cultural Patterns and Processes . Allen G. Noble and Ashok K. Dutt , eds. The God that Limps: Science and Technology in the Eighties . Colin Norman . Geography: An Introductory Perspective . Robert E. Norris , Keith D. Harries and John D. Vitek . The Politics of Technology Assessment . David M. O'Brien and Donald A. Marchand . Ethnic Segregation in Cities . Ceri Peach , Vaughan Robinson and Susan Smith , eds. Churches and Church Membership in the United States, 1980 . Bernard Quinn , Herman Anderson , Martin Bradley , Paul Goetting and Peggy Shriver . Energy in Australia: Politics and Economics . Hugh Saddler . Development from Above or Below? The Dialectics of Regional Planning in Developing Countries . Walter B. Stóuhr and D. R. Fraser Taylor , eds. Human Impact on the Ecosystem . Joy Tivy and Greg O'Hare . Plants and People: Vegetation Change in North America . Thomas R. Vale . The Mapmakers: The Story of the Great Pioneers in Cartography from Antiquity to the Space Age . John Noble Wilford .     

征地区片综合地价与土地城市化的空间耦合分析——以北京市为例

基于征地区片综合地价分析土地价格与土地城市化的速率和强度的空间耦合关系,研究结果表明,在时间和空间尺度上,土地价格与土地城市化的速率和强度存在明显的相互关系,这一耦合作用形成了土地城市化在空间上的分异性状.作为与土地城市化存在空间耦合关系的土地价格可以作为引导土地城市化速度、强度和空间形态的有效调控手段.通过对土地价格的影响,可以引导土地城市化在空间上和时间上达成合理的演替趋向.     

利用探索式空间数据解析北京城市空间经济发展模式

城市经济空间结构是城市研究和城市规划基本内容之一。利用其探索式空间数据分析方法,根据1949-2004年企业登记就业数据在邮政区尺度上对北京市1949年以来城市空间经济发展进行了探讨。基于空间邻近矩阵和不同距离矩阵的Global Moran'sI和Local Moran'sI都表明解放后市区并没有明显的经济集聚,50多年来空间经济发展模式几乎都是以市区为核心集聚式发展;尽管郊区一些重要乡镇呈现出发展势头,但几乎没有和周边地区形成互动关系,而是和市中心或其它地区保持较强的联系。分析还表明,北京地区经济的空间相互作用在计划经济时代大体在60km以内,市场经济时代(1983-2002年)提高到75km。北京经济空间模式经历了以下6个阶段:①1957-1982年,中心集中发展;②1983-1987年,沿京津廊道空间组织;③1988-1992年,北部为主的城市中心发展;④1993-1997年,城市中心集中扩张模式;⑤1998-2002年,城市中心填充发展;⑥2002-2004年,出现了城市空心化结构态势,空间经济组织面临新一轮重组。     

从水的载体功能看西北地区经济发展与水资源配置

从水的载体功能的原理出发,分析了西北水资源的特征,探讨了西北地区经济发展与水资源配置问题及对策。当前西北地区经济发展已造成水资源的高负荷状态,资源开发利用若仍然保持现有的方式和结构,无疑会产生更加严重的生态问题。基于此,分别提出了西北地区水资源高负荷的解决对策,以增加水的承载力,从而维持水的载体功能的基本平衡。     

Examining Risk in Mineral Exploration

Successful mineral exploration strategy requires identification of some of the risk sources and considering them in the decision-making process so that controllable risk can be reduced. Risk is defined as chance of failure or loss. Exploration is an economic activity involving risk and uncertainty, so risk also must be defined in an economic context. Risk reduction can be addressed in three fundamental ways: (1) increasing the number of examinations; (2) increasing success probabilities; and (3) changing success probabilities per test by learning. These provide the framework for examining exploration risk. First, the number of prospects examined is increased, such as by joint venturing, thereby reducing chance of gambler's ruin. Second, success probability is increased by exploring for deposit types more likely to be economic, such as those with a high proportion of world-class deposits. For example, in looking for 100+ ton (>3 million oz) Au deposits, porphyry Cu-Au, or epithermal quartz alunite Au types require examining fewer deposits than Comstock epithermal vein and most other deposit types. For porphyry copper exploration, a strong positive relationship between area of sulfide minerals and deposits' contained Cu can be used to reduce exploration risk by only examining large sulfide systems. In some situations, success probabilities can be increased by examining certain geologic environments. Only 8% of kuroko massive sulfide deposits are world class, but success chances can be increased to about 15% by looking in settings containing sediments and rhyolitic rocks. It is possible to reduce risk of loss during mining by sequentially developing and expanding a mine—thus reducing capital exposed at early stages and reducing present value of risked capital. Because this strategy is easier to apply in some deposit types than in others, the strategy can affect deposit types sought. Third, risk is reduced by using prior information and by changing the independence of trials assumption, that is, by learning. Bayes' formula is used to change the probability of existence of the deposit sought on the basis of successive exploration stages. Perhaps the most important way to reduce exploration risk is to employ personnel with the appropriate experience and yet who are learning.     

Discussion on Nontraditional Mineral Resources

INTRODUCTIONMineral resources is nonrenewable.L imited traditionalmineral resources have been gradually used up,resulting inthe shortage of mineral resources for future economic develop-ment.On the other hand,the emerging industries demand formore mineral resources.All of these questions are focused onhow to find and develop adequate resources so as to satisfy theneeds of social and economic developm ent in the world.Theway to solution to these questions is that nontraditional re-sources …     

空间经济学研究的相关进展与评述

空间经济学是近年来世界经济学和地理学领域研究的热点,本文从历史发展的角度,阐述了比较优势和贸易理论、区位理论、新经济地理理论对空间经济学的主要贡献及观点。可持续发展条件下的空间均衡对空间经济学提出新的理论要求,为此,空间经济学研究应从传统经济目标转向经济、社会、环境综合效用最大化的目标,建立空间异质下的空间均衡的系统分析框架,生态空间分布及其与经济活动开发空间的合理配置理论,使理论模型更为逼近现实,提高理论的解释力。     

气候变化影响及其适应的经济学评估——英国"斯特恩报告"关键内容解读

分析了英国尼古拉斯·斯特恩领导完成的"从经济学角度看气候变化"报告的主要内容,并从科学基础、气候变化中的经济学问题、减排行动的政策与经济因素、适应行动的效益分析以及全球合作应对气候的意义等5个方面对报告的主要内容、立场和结论进行了介绍.报告认为,气候变化是不争的事实,如果人类按照目前的模式继续发展下去,到21世纪末,全球温度可能会升高2～3℃以上,这将会造成全球经济的GDP比重下挫5%～10%,而贫穷国家则会超过10%.如果现在即采取措施,在2050年前把温室气体浓度控制在450×10-6～550×10-6的水平上,减排的成本大约仅占GDP的1%.报告提出,要建立长期稳定的碳价格政策、低碳技术发展政策、消除阻碍减排行动的障碍因素,保证温室气体减排行动的有效实施.全球合作和以适应为目标的气候行动目前在经济上是可行的,并有利于气候目标的实现.