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41.
An interval-parameter multi-stage stochastic programming model for water resources management under uncertainty 总被引:1,自引:0,他引:1
In this study, an interval-parameter multi-stage stochastic linear programming (IMSLP) method has been developed for water resources decision making under uncertainty. The IMSLP is a hybrid methodology of inexact optimization and multi-stage stochastic programming. It has three major advantages in comparison to the other optimization techniques. Firstly, it extends upon the existing multi-stage stochastic programming method by allowing uncertainties expressed as probability density functions and discrete intervals to be effectively incorporated within the optimization framework. Secondly, penalties are exercised with recourse against any infeasibility, which permits in-depth analyses of various policy scenarios that are associated with different levels of economic consequences when the promised water-allocation targets are violated. Thirdly, it cannot only handle uncertainties through constructing a set of scenarios that is representative for the universe of possible outcomes, but also reflect dynamic features of the system conditions through transactions at discrete points in time over the planning horizon. The developed IMSLP method is applied to a hypothetical case study of water resources management. The results are helpful for water resources managers in not only making decisions of water allocation but also gaining insight into the tradeoffs between environmental and economic objectives. 相似文献
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43.
One of the main concerns of the Common Fisheries Policy (CFP) lies in guaranteeing consistency among the different implemented actions. The main concern is establishing a relationship between the levels of compliance with the Multi-annual Guidance Programme (MAGP), the adoption of total allowable catches (TACs), and the levels of compliance with rules by producers. 相似文献
44.
The assessment of sustainable development is a relatively recent advent in policy and the evaluation of industry structural adjustments. Although the elements of economic and environmental assessment have been relatively well developed and accepted, the effective inclusion of ‘social’ aspects in assessments of sustainable development are still being grappled with. 相似文献
46.
针对心内复杂结构,本文结合三维虚拟内窥镜技术和二维常规观测截面功能,开发了双源CT心脏图像的显示系统。用户可以在本系统内以自动和交互式的两种方式观测心内结构。自动方式,对造影剂增强的数据部分进行基于欧式距离的三维骨架化得到规划路径,光线投射法根据已算出的欧式跳过空白区域,减少了绘制计算量;交互方式,用户可以随时从内窥镜视角切换到当前视点所在的任意截面,便于进行二维和三维的结构和病理综合分析。而且,本系统根据规划路径自动检测标准四腔切面,改善临床检查的效率。本系统采用基于CUDA的体绘制技术有效实现了对心内解剖结构更加直观的观测,便于心脏疾病的诊断和治疗。 相似文献
47.
Small-scale marine fisheries policy in Vietnam 总被引:1,自引:0,他引:1
Vietnam's marine fisheries are considered to be small scale and are concentrated in coastal near-shore waters. This has resulted in heavy pressure on near-shore fisheries resources. Near-shore fisheries are considered by fishers and the government to be over-exploited, causing hardship for many coastal communities. This paper reviews and analyzes changes in policy towards small-scale fisheries in Vietnam over the last two decades. The primary issues facing the small-scale fisheries in Vietnam are to restructure the near-shore fisheries and to address over-capacity. Recommended actions include improved fisheries statistics, resources for provincial fisheries staff, and a coordinated and integrated approach involving a mixed strategy of resource management; resource restoration; economic and community development; and new governance arrangements. 相似文献
48.
The live reef fish for food trade is a highly significant fishery that provides income for many coastal communities in the Asia-Pacific region but faces challenges relating to sustainability. This paper draws attention to the large gaps that exist between policy and practice in the live reef fish for food trade in Palawan, Philippines. While many policies have been introduced over many years, effective implementation remains a challenge. We show how the implementation of successive sets of policies has been hindered by three broadly inter-related features of the local social landscape: the capacity of government institutions and legal frameworks to implement regulations, the distinctive culture of fisheries governance in the Philippines, and the perspectives and practices of local fishers themselves. By focusing on the gaps between policy and practice, we highlight the ongoing need to examine more explicitly the ways in which local contexts shape the effectiveness of implementation, enforcement and policy more generally. 相似文献
49.
学科树视角下地理学和建筑学人居环境研究比较 总被引:1,自引:0,他引:1
本文从学科树视角比较分析地理学和建筑学的人居环境研究进展。首先,梳理研究脉络,指出两个学科具有相同的“树根”(即五大系统和五大层次)、“树干”(即九大主题和八大尺度)和“树枝”(即33个研究领域),以及相异的“树叶”(即各领域数量迥异的研究成果)。其次,比较研究成果特点,发现两个学科成果差异明显,表现为在适宜性等6个二级主题上,地理学成果较多,建筑学成果较少;在规划等6个二级主题和建筑尺度上,建筑学成果较多,地理学成果较少;在空间格局等12个二级主题和城市等6个尺度上,两个学科成果均较多,但侧重点不同;在行为二级主题和全球尺度上,两个学科成果均较少,但侧重点不同。最后,剖析学科成果差异的生成逻辑,并展望未来进路。学科成果差异的逻辑起点是学科门类差异,逻辑链条是“学科门类—学科特性—研究主体—研究偏好—研究范式—研究成果”的差异传导机制,其中研究范式差异是链条中的重要环节。未来人居环境研究应促进框架延伸化、主题展拓化、尺度统筹化、数据多源化、方法混合化等范式提升,同时回应全球化、美好人居、突发事件、跨学科等现实需求。 相似文献
50.
B.P.Singh 《地学前缘(英文版)》2013,4(2):199-212
The Paleogene succession of the Himalayan foreland basin is immensely important as it preserves evidence of India-Asia collision and related records of the Himalayan orogenesis. In this paper, the depositional regime of the Paleogene succession of the Himalayan foreland basin and variations in composition of the hinterland at different stages of the basin developments are presented. The Paleogene succession of the western Himalayan foreland basin developed in two stages, i.e. syn-collisional stage and post-collisional stage. At the onset, chert breccia containing fragments derived from the hanging walls of faults and reworked bauxite developed as a result of erosion of the forebulge. The overlying early Eocene succession possibly deposited in a coastal system, where carbonates represent barriers and shales represent lagoons. Up-section, the middle Eocene marl beds likely deposited on a tidal flat. The late Eocene/Oligocene basal Murree beds, containing tidal bundles, indicate that a mixed or semi-diurnal tidal system deposited the sediments and the sedimentation took place in a tide-dominated estuary. In the higher-up, the succession likely deposited in a river-dominated estuary or in meandering rivers. In the beginning of the basin evolution, the sediments were derived from the Precambrian basement or from the metasediments/volcanic rocks possessing terrains of the south. The early and middle Eocene (54.7–41.3 Ma) succession of the embryonic foreland possibly developed from the sediments derived from the Trans-Himalayan schists and phyllites and Indus ophiolite of the north during syn-collisional stage. The detrital minerals especially the lithic fragments and the heavy minerals suggest the provenance for the late Eocene/Oligocene sequences to be from the recycled orogenic belt of the Higher Himalaya, Tethyan Himalaya and the Indus-suture zone from the north during post-collisional stage. This is also supported by the paleocurrent measurements those suggest main flows directed towards southeast, south and east with minor variations. This implies that the river system stabilized later than 41 Ma and the Higher Himalaya attained sufficient height around this time. The chemical composition of the sandstones and mudstones occurring in the early foreland basin sequences are intermediate between the active and passive continental margins and/or same as the passive continental margins. The sedimentary succession of this basin has sustained a temperature of about 200 °C and undergone a burial depth of about 6 km. 相似文献