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41.
应用应力摩尔圆方法,探讨了断层能动度与构造应力方向和断层面几何特征的关系,并与断层活动速率对比分析,将断层失稳度定量化。最后结合地震时间逼近度,求出了断层地震危险度的定量指标,将理论模型应用于渭河盆地南缘断层,取得了较好效果。  相似文献   
42.
The concept of base-multiplier analysis is that export activities constitute the economic base of a region, whereas the other economic activities that sell their goods and services to the local residents grow or shrink depending on the performance of the base activities. These concepts, with origins extending at least as far back as the early 1900s, have reached maturity and are widely applied. The attractiveness of an economic base model (EBM) draws in its simplicity in expressing the power of demand in regional income determination. Extensive literature has grown up around the economic base theory, however, systematic publications concerning empirical application are scarce and focus mostly on the socio-economic dimension of the analyzed system. Such territorially oriented economic models are useful in a variety of decision making procedures; preparation of annual budgets, short-run market demand forecasting, longer-term growth strategies. The purpose of this article is to present a practical application of EBM to the geographical area of the Guadiana Estuary, on the south coast of Portugal. The interest of the EBM application in this case study includes its integration in a broader project that applies a Systems Approach Framework (SAF) towards Integrated Coastal Zone Management (ICZM). There are three pillars of sustainability considered here: social, ecological and economic, hence, the article not only describes EBM application but also how it has been use to demonstrate a chain of events resulting from the interaction between the ecological and the socio-economic sub systems of the area. The results obtained will probably raise the usual criticism to which the economic base model has been exposed previously; however it provides unequivocal evidence that a truly interdisciplinary approach to a given territorial target can be successfully shared with end users and the research community.  相似文献   
43.
The SAF (Systems Approach Framework) encompasses the ecological, social and economic components of coastal zones and aims to establish a permanent dialogue between scientists, stakeholders and policy makers working within European coastal zones for developing effective ICZM (Integrated Coastal Zone Management). The objective of the present study is to test the application of the SAF for defining eutrophication management options in the Ria Formosa, Portugal. Stakeholders were identified and the issue of eutrophication was agreed upon. Having defined the virtual system, the conceptual model of the Ria Formosa was developed. The formulation of the conceptual model into a mathematical model representing the ecological, social and economic components of the system is then discussed. The linking variable of the three components within the simulation model, as well as the scenarios to be run are then explored. The role of scientists as facilitators within the deliberation process is discussed, and a format by which the final output package could be disseminated is suggested. This case study demonstrates how the SAF could successfully be applied to the management of eutrophication in the Ria Formosa. It also suggests ways in which this approach may be adapted to address unique coastal systems with specific system characteristics.  相似文献   
44.
Geographers have become increasingly engaged with the notion of policy mobility. It is argued that in a globalised world policies have become more internationally mobile: we now live in an era of ‘fast policy’. Drawing on core concepts of mobility, neoliberalisation, and globalisation - and with a background primarily in geography and urban studies - policy mobility scholars have developed new ideas about how policies circulate internationally. In the process, however, theories of policy change developed within political science have been rather overlooked. In this paper it is shown how a political science theory with a shared interest in flows – the Multiple Streams Approach (MSA) – is complementary to policy mobilities scholarship. Two issues in particular are illuminated by the MSA: first, what constitutes policy, and, second, the role of the nation state in structuring the possibilities for, and timing of, policy change. In turn, policy mobilities scholarship highlights the different geographies of the multitude of objects, ideas, problems, processes, organisations, and regulations that constitute policy. It also raises questions about the validity of analytically separating politics from policy proposals, as advocated by the MSA. These issues are considered using the empirical case of smart electricity metering policy in Australia, in the period 2000–2015.  相似文献   
45.
This study examines the reorganization of formal coordination structures of a unique international public organization involved in marine governance in Europe, namely the structural reorganizations of the International Council for the Exploration of the Sea (ICES) between 1999 and 2009. The findings indicate that the reorganizations of ICES’ formal coordination structures were not driven primarily for reasons of efficiency, by clear and consistent goals, and by clear means-ends considerations for organizational design as proposed by rational perspectives in organization theory. Instead, the formal coordination structures have also been adapted to live up to changing expectations in the institutional environment, to modern management concepts in marine governance such as the Ecosystem Approach to Management (EAM), and to ensure the legitimacy of the organization. However, it is also found that institutional explanations alone are insufficient to comprehensively understand why the formal organizational structures of ICES were reorganized. Instrumental and cultural perspectives in organization theory as well as resource-dependence theory additionally add to understand how ICES responded to external demands and why organizational structures have been changed.  相似文献   
46.
A Comprehensive Model for Evaluating Coalbed Methane Reservoirs in China   总被引:3,自引:0,他引:3  
Coalbed methane reservoir (CBMR) evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and methods to evaluate CBMR. Based on the geological surveys, laboratory measurements and field works, a four-level analytic hierarchy process (AHP) model for CBMR evaluation is proposed. In this model, different weights are prioritized and assigned on the basis of three main criteria (including reservoir physical property, storage capacity and geological characteristics), 15 sub-criteria, and 18 technical alternatives; the later of which are discussed in detail. The model was applied to evaluate the CBMR of the Permo-Carboniferous coals in the Qinshui Basin, North China. This GIS-based fuzzy AHP comprehensive model can be used for the evaluation of CBMR of medium-high rank (mean maximum vitrinite reflectance 〉0.5 %) coal districts in China.  相似文献   
47.
分析了浙江天台-宁海地区嵊县组第3沉积层的孢粉样品11个,该层时代属晚中新世.其中,在宁海县黄泥塘村和大路下村各采集4个,天台县家湖村采集3个;样品岩性主要为浅灰色至灰褐色湖相沉积的泥岩至泥质粉砂岩,部分样品含较多硅藻土(采样地点分布范围29°8′~ 29°10′N,121°14′~121°16′E).经化学处理,除HNT-11,DLX-1和DLX-2以外,在其余8个样品中发现了丰富且保存完好的孢粉化石,共鉴定39个类群,归属23科,建立了以栎属(Quercus)—松属(Pinus)—禾本科(Poaceae)——菱属(Trapa)为主要特征的孢粉组合.结合同层位植物大化石记录,推论晚中新世天台-宁海及其周边地区的植被类型丰富,以具有一定垂直地带性的森林植被为主:自山麓向上,随海拔升高,由常绿阔叶林逐渐向常绿、落叶阔叶混交林以及落叶阔叶林过渡;研究区生长有松属(Pinus)及竹类植物,草本植物生长茂盛,并生长有一定量的蕨类植物;研究区内湖泊、池塘及沼泽等平静的淡水水体普遍存在,使得菱属等水生草本及盘星藻(Pediastrum)等淡水藻类广泛生长.该植被类型与现今浙江兼具一定垂直地带性的典型中亚热带常绿阔叶林较为相似.通过对当前孢粉组合应用共存分析法,定量重建了晚中新世研究区的8个古气候参数,即年平均气温(MAT) 17.0~ 18.5℃,年平均降水量(MAP) 979.0 ~1722.0mm,最热月平均气温(WMT) 26.5~28.4℃,最冷月平均气温(CMT) 3.3 ~ 7.7℃,平均最大月降水量(MMaP) 176.2~265.0mm,平均最小月降水量(MMiP)7.0~31.6mm,平均最热月降水量(MWP) 165.5~ 232.5mm以及气温年较差(DT) 18.2~ 21.5℃,表明晚中新世研究区的气候温暖湿润,同该区现代气候相近.  相似文献   
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