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1.
Damage models for natural hazards are used for decision making on reducing and transferring risk. The damage estimates from these models depend on many variables and their complex sometimes nonlinear relationships with the damage. In recent years, data‐driven modeling techniques have been used to capture those relationships. The available data to build such models are often limited. Therefore, in practice it is usually necessary to transfer models to a different context. In this article, we show that this implies the samples used to build the model are often not fully representative for the situation where they need to be applied on, which leads to a “sample selection bias.” In this article, we enhance data‐driven damage models by applying methods, not previously applied to damage modeling, to correct for this bias before the machine learning (ML) models are trained. We demonstrate this with case studies on flooding in Europe, and typhoon wind damage in the Philippines. Two sample selection bias correction methods from the ML literature are applied and one of these methods is also adjusted to our problem. These three methods are combined with stochastic generation of synthetic damage data. We demonstrate that for both case studies, the sample selection bias correction techniques reduce model errors, especially for the mean bias error this reduction can be larger than 30%. The novel combination with stochastic data generation seems to enhance these techniques. This shows that sample selection bias correction methods are beneficial for damage model transfer.  相似文献   
2.
南慧英 《北方论丛》2015,(5):104-109
1860年后,俄国远东地区出现大量亚洲移民,其中包括中国人、朝鲜人和日本人。日本人数量较少,主要进行捕鱼作业。中国人和朝鲜人则遍布俄国远东各个经济领域。虽然俄国政府对外来移民的政策几经调整,但在远东劳动力极度匮乏的情况下,中国人和朝鲜人在俄国各经济领域仍然得到广泛使用,中国人和朝鲜人不仅为俄国远东提供了廉价劳动力,也为远东地区经济发展,边区稳定做出了重要贡献。  相似文献   
3.
The debate on strategic spatial planning highlights the limitations of statutory land use planning in weighing up future options for spatial development, particularly in instances of rapid change. This paper draws on this debate in order to analyse planning institutions and practices in Finland. The case in point is the south-eastern border region where interdependencies with Russia, particularly shopping tourism, have created pressures on land use and led to contentious planning processes between regional and central levels of government. It is argued that, in the absence of cross-border spatial co-ordination, there is a need to establish links between regional land use planning and visions of spatial scenarios in the national context.  相似文献   
4.
20世纪20年代初期中苏建交谈判期间,苏俄从其自身国家安全利益出发,采取强行出兵外蒙追剿白匪和坚持长期驻军库伦的作法,来占有当时主权属于中国的外蒙古地区,在外蒙古问题上对华采取了大国沙文主义和民族利己主义政策.  相似文献   
5.
策略的选择关乎黑龙江省老工业基地改造的质量和效率,而老工业基地改造的关键在于运用高新技术促进产业结构的调整和产业技术的升级。俄罗斯是一个极具科技实力和潜力的国家,黑龙江省有着与俄科技合作的地缘优势、文化优势、人才优势以及历史和现实工作基础。因此,可以从与俄科技合作的视角探讨黑龙江省老工业基地改造的策略。应从战略高度审视利用与俄科技合作改造黑龙江省老工业基地,提升核心竞争力,走内涵式发展道路;重视软环境建设;分层规划;分组实施;重点支持若干领域,带动整体发展。  相似文献   
6.
从制度变迁的视角看俄罗斯的10年演变   总被引:1,自引:0,他引:1  
运用制度变迁的理论深入分析了俄罗斯变迁的动因和绩效 ,指出俄罗斯的制度变迁具有强制性、根本性、激进性和移植性四大特点。它虽然取得了局部成效 ,但付出了过高的成本和巨大的代价 ,并且没有开辟出一条新的发展道路 ,犯了理想主义错误。在制度变迁中应当辩证地对待本国的制度遗产 ,注重营造新制度运行的制度环境 ,努力开展制度创新。制度变迁是一个长期而又曲折的过程 ,俄罗斯正在努力进行新的探索  相似文献   
7.
Because of the inherent complexity of biological systems, there is often a choice between a number of apparently equally applicable physiologically based models to describe uptake and metabolism processes in toxicology or risk assessment. These models may fit the particular data sets of interest equally well, but may give quite different parameter estimates or predictions under different (extrapolated) conditions. Such competing models can be discriminated by a number of methods, including potential refutation by means of strategic experiments, and their ability to suitably incorporate all relevant physiological processes. For illustration, three currently used models for steady-state hepatic elimination--the venous equilibration model, the parallel tube model, and the distributed sinusoidal perfusion model--are reviewed and compared with particular reference to their application in the area of risk assessment. The ability of each of the models to describe and incorporate such physiological processes as protein binding, precursor-metabolite relations and hepatic zones of elimination, capillary recruitment, capillary heterogeneity, and intrahepatic shunting is discussed. Differences between the models in hepatic parameter estimation, extrapolation to different conditions, and interspecies scaling are discussed, and criteria for choosing one model over the others are presented. In this case, the distributed model provides the most general framework for describing physiological processes taking place in the liver, and has so far not been experimentally refuted, as have the other two models. These simpler models may, however, provide useful bounds on parameter estimates and on extrapolations and risk assessments.  相似文献   
8.
Russia’s role in ‘animation’ of the Kyoto Protocol was crucial. Its initial vacillation on ratification was predominantly due to political bargaining with the EU. Domestic economic rationales [i.e. impacts of emission trading and Joint Implementation (JI) projects] were important to a much lesser extent and environmental motives did not seem to play any role in the decision. Since the Protocol entered into force, there have been significant delays in complete establishment of policy implementation frameworks, which are necessary for Russia to start benefiting from JI and emission trading. Only recently, in 2007, have GHG inventories and a national registry been established and the responsibilities for implementation of the Protocol and JI among the government departments have been distributed only to a certain extent. Some constraints hindering JI projects, such as vague legislation, an unfavourable economic climate, lack of commitment to JI projects, corruption, xenophobia, state and agency ‘capture’ still remain.   相似文献   
9.
A quantitative criterion for ranking the different scenarios of nuclear and radiological terrorism has been developed. The aim of the model is not to predict terroristic events but only to indicate which scenario has the higher utility from the point of view of a terroristic organization in terms of balance between factors favoring and discouraging the attack, respectively. All these factors were quantified according to a scoring system that takes into account the logarithmic relationship between perceptions and stimuli. The criterion was applied to several scenarios, each of which was modeled in a simple but not trivial way in order to estimate the expected damage in terms of probable life losses from both radiative and nonradiative effects. The outcome from the ranking method indicates that the attractive scenario appears to be the detonation of a low yield improvised nuclear device in the metropolitan area of a major city.  相似文献   
10.
日本和俄罗斯作为能源互补的两个国家,本具备良好的合作潜力,但受历史、体制以及领土争端等因素的制约,两国关系一直徘徊不前。在全球化条件下,能源合作对双方的关系的确有某种积极的因素,然而,由于双方外交战略和本国具体情况所限,因此,能源对拉近两国之间的关系作用受到限制。但是,随着能源合作的快速发展,日俄经济合作程度偏低的状况迟早会得到解决。  相似文献   
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