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961.
J. Henry Owusu 《The Professional geographer》2001,53(2):230-247
In 1983, Ghana embarked on a program of structural adjustment under the auspices of the World Bank and the International Monetary Fund, to resuscitate the economy and to foster development. This paper utilizes the Lagos Plan of Action, a comprehensive, continent‐wide effort and African‐led policy strategy for the economic development of the African continent, to examine the contribution of adjustment to the development of an integrated economy in Ghana. Adjustment is examined as a form of structural transformation, as evidenced by the emergent intranational (intra‐ and inter‐sectoral) and international linkages in the formal wood processing industry, a key sector with tremendous potential for such linkages. Intranationally, this study shows that, as in the pre‐adjustment years, inter‐sectoral linkages, although important, were not dynamic enough to play a significantly galvanizing role in the nation's economic development. However, intra‐sectorally, a dramatic expansion in lumber exports led to an unprecedented constriction in the traditional forward linkage between sawmills and downstream processors. This forced the latter to depend on the informal sector for inputs. Internationally, Ghanaian firms operated as subcontractors of convenience for firms overseas (particularly in Europe) via an expanded forward linkage, reflecting a new “colonial relationship” under the program. 相似文献
962.
Drew Lawrence J. Karlinger Michael R. Armstrong Thomas R. Moore Richard B. 《Natural Resources Research》1999,8(2):137-152
Exploratory variography was used to examine the spatial continuity of water–well yields in the Pinardville 7
Minute Quadrangle in southern New Hampshire and to link the variography to the characteristics of the fractured igneous and metamorphic rocks within the aquifer system. In addition to the analyses of variograms computed by using data from 939 wells, analyses were performed on subsets of the data that were stratified according to the level of yield and to five rock types. The stratification according to yield was defined by using the industry standard of a high-yield well that produces 40 gallons per minute or more. The stratification of the low-yield wells by rock type was defined by using the classification on the bedrock map for the State of New Hampshire. Although the variability is high in the low-yield wells, as indicated by the large nugget value, overall continuity ranges to 6000 feet in the fracture zones in which these wells have been drilled. This continuity is dominant in the northwesterly direction, as indicated by the directional variography. This result is consistent with the general trend in the larger tectonic configuration of the region. A lack of spatial correlation for 81 high-yield wells is consistent with the geologic interpretation that these wells occur in locally determined configurations of sheeting and steeply dipping fractures. Yield data in only three of the five rock types were sufficient for variography. Within these three, the dominant direction of the correlation structure ranged from northwesterly for the Massabesic Gneiss Complex to northeasterly for the Rangeley Formation to northerly for the Spaulding Granite, where the signature of the continuity in the low-yield wells is predominately attributed to the fracture system. 相似文献
963.
对地震活动性进行层次结构分析可划分出不同的地震区带,中国大陆的地震活动可分为9个地震区带,分析各个区带的地震活动性可作出某一活跃期强震发生主体地区的判别,对某一个地震区带的地震活动进行层次结构分析可作出地震危险区预测。用震源面投影图代替点投影的震中分布图可更合理地解释一个构造带上强震的发生过程,更清楚地勾画出未来强震的孕震范围。对强震破裂区闭锁段、背景空区、孕震空区的关系用实测震例进行了解释。 相似文献
964.
哈纳斯湖地区地貌与湖的成因 总被引:1,自引:0,他引:1
哈纳斯湖位于阿尔泰山深处,最大水深188.5m,平均水深122.1m。横断面具典型的箱形形态,在其底部存在现代活动地堑。湖盆的成因是强烈的构造断陷加上山谷冰川的创蚀及终碛垄的堰塞。随着终绩垄被出流下切,湖泊面积变小。 相似文献
965.
闽北政和地区晋宁期变质岩系的构造变形特征 总被引:2,自引:0,他引:2
通过宏观和微观构造的详细研究表明,政和地区变质岩石共经历了四期构造变形作用。其中,前三期构造变形作用发生于晋宁期,第四期构造变形作用为后期加里东运动叠加的产物,四期构造变形作用所形成的构造形迹各不相同。变质岩石的区域性面理是第二期构造变形作用形成的轴面叶理,不代表原始沉积层理的产状。 相似文献
966.
Structural pattern of eastern Himalayan syntaxis in Namjagbarwa and its formation process 总被引:20,自引:4,他引:16
ZHANG Jinjiang Jl Jianqing ZHONG Dalai DING Lin & HE Shundong. Department of Geology Peking University Beijing China . Institute of Geology Geophysics Chinese Academy of Sciences Beijing China Correspondence should be addressed to Zhang Jinjiang 《中国科学D辑(英文版)》2004,47(2):138-150
The structural pattern of the eastern Himalayan syntaxis in Namjagbarwa consists of two series of structures with different styles. One series compiles the earlier ductile contrac-tional and lateral-slip deformation system, formed by nearly north-south shortening within the syntaxis, left-lateral and right-lateral slipping along its western and eastern boundaries respectively. They were possibly produced by the indentation of the Indian continent into Asian continent after India-Asia collision. The peak deformation-metamorphic ages in these structures are 62-60 Ma, -23 Ma and -13 Ma. The other series is composed of ductile-brittle normal faults distributing concentrically and dipping toward the outsides of Namjagbarwa Peak. They were probably the collapse structures caused by rapid uplift in a later time and the beginning ages for the normal faulting are about 7.3-6.3 Ma. 相似文献
967.
Shen Bing 《中国地理科学(英文版)》2004,14(2):97-103
While China’s economic growth has been impressive since 1978, regional disparity in terms of provincial per capita GDP has
been increasing. On the other hand, this rapid but uneven growth was accompanied by China’s deepening openness and structural
reforms including the development of non-state-owned enterprises (non-SOEs) and fiscal decentralization. Based on quantitative
analyses, this paper tries to explore the features of regional disparity in China and the relationships between regional growth
and China’s openness and economic structure reforms in the period from 1981 to 2000. The paper finds that the catching-up
of the coastal region to the initially rich provinces, which are mainly located in inland areas, brought about a convergence
of the growth pattern across provinces in the 1980s. The subsequent divergence in the provincial growth rates between the
coast and the interior generated an enlarging regional disparity in China in the 1990s. The ever-faster growth in the coastal
region was benefited by China’s openness and the development of non-state-owned enterprises. The development of non-state-owned
enterprises underlies the higher operational efficiency in the coastal region. Additionally, with the insignificant regression
results, fiscal decentralization was observed to facilitate faster growth in the coast region. The findings justify the initiative
of the "West Region Development Strategy" and offer some policy implications for China.
Biography: SHEN Bing (1966–), female, a native of Hebei Province, associate professor, specialized in regional economy and
urban development. E-mail: shenbing@mx.cei.gov.cn 相似文献
968.
Larry?A.?FahnestockEmail author Richard?Sause James?M.?Ricles Le-Wu?Lu 《地震工程与工程振动(英文版)》2003,2(2):255-268
Accurate estimates of ductility demands on buckling-restrained braced frames (BRBFs) are crucial to performance-based design of BRBFs. An analytical study on the seismic behavior of BRBFs has been conducted at the ATLSS Center, Lehigh University to prepare for an upcoming experimental program. The analysis program DRAIN-2DX was used to model a one-bay, four-story prototype BRBF including material and geometric nonlinearities. The bucklingrestrained brace (BRB) model incorporates both isotropic and kinematic hardening. Nonlinear static pushover and timehistory analyses were performed on the prototype BRBF. Performance objectives for the BRBs were defined and uscd to evaluate thc time-history analysis results. Particular emphasis was placed on global ductility demands and ductility demands oa the BRBs. These demands were compared with anticipated ductility capacities. The analysis results, along with results from similar previous studics, are used to evaluate the BRBF design provisions that have been recommended for codification in the United States. Thc results show that BRB maximum ductility demands can be as high as 20 to 25. These demands significantly exceed those anticipated by the BRBF recommended provisions. Results from the static pushover and timehistory analyses are used to demonstrate why the ductility demands exceed those anticipated by the recommended provisions.The BRB qualification testing protocol contained in the BRBF recommended provisions is shown to be inadequate because it requires only a maximum ductility demand of at most 7.5. Modifications to the testing protocol are recommended. 相似文献
969.
初论造山带古地理学 总被引:21,自引:2,他引:19
造山带古地理学属构造古地理学 ,是造山带地层学的姐妹学科 ,其核心是活动论构造观。简述了造山带古地理学的形成和内涵 ,重点讨论了地质记录已发生移位、歪曲和混杂的造山带地区 (或经造山作用改造的克拉通地区 )正确地进行构造—古地理重建的三个问题 :一是不能用“将今论古”的方法恢复地史期间的隆起区和堆积区 ,地史期间的物源区并非一成不变 ,要充分认识物源供应的多样性和多重性 ;二是沉积相带的展布受区域构造应力场及基底构造格局控制 ,要特别重视边缘相及其物源区的研究 ;三是辨析原生沉积盆地与构造盆地 ,对盆地进行正确的构造复位是古地理重建的基础。 相似文献
970.
甘肃金塔煤田构造分析 总被引:2,自引:0,他引:2
甘肃金塔及其所在的河西地区均是煤炭资源严重缺乏的地区。区内尽管煤点出露较多,但在深部煤层常常缺失或尖灭,针对这一现象,本文从构造单元划分人手,运用板块构造学的分析方法对本区的构造活动史进行了简明的阐述,断陷盆地成为本区赋煤的主要构造。 相似文献