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71.
针对不同评价指标对决策结果影响权重多样性的问题,建立多属性决策模型对平台主尺度方案进行优化决策。基于自升式平台主体设计参数数据库,采用BP人工神经网络建立平台主尺寸关键参数多变量预测模型,在此基础上开展主尺度方案正交优化设计。将桩腿屈服强度、屈曲稳性、整体抗倾稳性作为平台安全适用性评估准则,进一步运用多属性决策理论,建立基于信息熵的自升式平台主尺度方案决策方法。研究结果表明,BP人工神经网络预测模型具有较高的预测精度;多属性决策模型可以将平台结构安全适用性定量评估引入方案决策过程中,而且综合考虑了不同评价指标对平台主尺度设计方案的影响程度及敏感性;最终,对SD-400自升式平台主尺度进行优化决策,验证了该方法的工程适用性。  相似文献   
72.
Effective climate policy will consist of mitigation and adaptation implemented simultaneously in a policy portfolio to reduce the risks of climate change. Previous studies of the tradeoffs between mitigation and adaptation have implicitly framed the problem deterministically, choosing the optimal paths for all time. Because climate change is a long-term problem with significant uncertainties and opportunities to learn and revise, critical tradeoffs between mitigation and adaptation in the near-term have not been considered. We propose a new framework for considering the portfolio of mitigation and adaptation that explicitly treats the problem as a multi-stage decision under uncertainty. In this context, there are additional benefits to near-term investments if they reduce uncertainty and lead to improved future decisions. Two particular features are fundamental to understanding the relevant tradeoffs between mitigation and adaptation: (1) strategy dynamics over time in reducing climate damages, and (2) strategy dynamics under uncertainty and potential for learning. Our framework strengthens the argument for disaggregating adaption as has been proposed by others. We present three stylized classes of adaptation investment types as a conceptual framework: short-lived “flow” spending, committed “stock” investment, and lower capacity “option” stock with the capability of future upgrading. In the context of sequential decision under uncertainty, these subtypes of adaptation have important tradeoffs among them and with mitigation. We argue that given the large policy uncertainty that we face currently, explicitly considering adaptation “option” investments is a valuable component of a near-term policy response that can balance between the flexible flow and committed stock approaches, as it allows for the delay of costly stock investments while at the same time allowing for lower-cost risk management of future damages.  相似文献   
73.
Although failures and successes in fisheries management are related to decision making processes, these are rarely analyzed in detail and even less often following quantitative or semi-quantitative approaches. Herein, we study the decision making process for Chile's most important fisheries using a binary decision model. This model evaluates the probability that an annual total allowable catch (TAC) will or will not be modified by the National Fisheries Council (NFC) based on biological, economic, and social factors. We also analyze some aspects of individual voting, particularly whether the members vote against or abstain from voting on the proposed TAC and if they prioritize resource conservation objectives. Our results indicate that the risk of over exploitation for many important stocks in Chile is aggravated by failures at the decision making level: the scientifically recommended TACs for those fisheries that generate higher levels of employment and have greater economic value are normally increased. This analysis shows that the NFC has clearly prioritized short-term economic and social objectives over resource conservation goals. We discuss the need to adjust the composition and functioning of the NFC in order to ensure long-term sustainability of the fisheries.  相似文献   
74.
在分析人工造浆阶段和风动造浆阶段原理及优缺点的基础上,开发研制出射流式水泥液制造器。通过对该设备主要构成部分结构的介绍,说明了其工作原理和使用方法。焦煤集团九里山矿14101工作面和古汉山矿11092(西)工作面的堵水实践证明,该设备的堵水率为100%,不仅可以提高注浆的速度及质量,降低劳动强度,改善注浆工地环境条件,而且具有价格便宜、设备安装简便、操作简单、容易维护,不受场地、注浆量大小、注浆点远近的限制等优点。  相似文献   
75.
The paper presents a comprehensive multi-objective hydrodynamic optimisation procedure and its application to the early design of a floating liquefied natural gas (LNG) terminal for improved seakeeping and wave attenuation characteristics on its lee side. Genetic algorithms are used to find the Pareto optima designs followed by multi-objective decision making procedures to select the optimum design among them. The paper addresses the definition of the relevant optimisation problem and the set-up and interface of relevant software tools, presents results of systematic studies with respect to the minimisation of the motion responses and wave elevation on the leeward side of free-floating terminals and concludes with analysis and critical review of the obtained results and their impact on terminal design.  相似文献   
76.
GIS和SDSS在高速公路选线之中的应用   总被引:6,自引:1,他引:6  
贾永刚  广红等 《地球科学》2001,26(6):653-656
以地理信息系统(GIS)和空间决策支持系统(SDSS)技术为基础,以地理信息系统工具CITYSTAR为平台,以VB为开发工具,在高速公路选线理论的指导下并考虑选线工作中的实际问题,对如何把GIS和SDSS应用到高速公路选线中进行了探讨,并以青岛、黄岛、灵山卫、南岭等环胶州湾地区为研究对象,初步设计出了高速公路选线决策支持系统。  相似文献   
77.
关于福建印支运动性质的讨论   总被引:1,自引:0,他引:1  
福建印支期强烈的抬升和伸展现象的地质事实已为广大地质工作者所公认,从抬升造陆作用,褶皱造山作用两探讨了印支运动的性质,认为鲆支运行的褶皱造山特征不明显,而隆升造陆特征显著。  相似文献   
78.
稻麦农业气象决策服务系统   总被引:1,自引:0,他引:1       下载免费PDF全文
RWAMDSS具有作物产量预报、作物气候评价、作物生长模拟、作物田间诊断专家系统等功能,是一个较为完整的农业气象决策服务系统。文章详细介绍了它的设计原理、结构及功能特点。  相似文献   
79.
刘洪春 《探矿工程》2005,32(5):41-43
CSF-40型薄壁防渗墙造墙机是在CSF-30型基础上重大升级改进推出的。主要介绍了其改进重点、关键部分及其特点、整机的技术性能指标、实际应用效果和推广应用建议等。  相似文献   
80.
基于3DS MAX的城市小区3维图的制作   总被引:5,自引:1,他引:5  
依据3DSMAX软件制作城市3维图的原理与方法,利用某一城市小区2维平面图的矢量数据,制作了城市小区3维图。重A介绍了基于3DSMAX环境的城市小区3维图的制作过程、制作工艺、建筑物的立体建模、材质贴图、灯光设置等关键技术。  相似文献   
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