A note of caution when interpreting parameters of the distribution of excesses

In climatology and hydrology, univariate Extreme Value Theory has become a powerful tool to model the distribution of extreme events. The Generalized Pareto Distribution (GPD) is routinely applied to model excesses in space or time by letting the two GPD parameters depend on appropriate covariates. Two possible pitfalls of this strategy are the modeling and the interpretation of the scale and shape GPD parameters estimates which are often and incorrectly viewed as independent variables. In this note we first recall a statistical technique that makes the GPD estimates less correlated within a Maximum Likelihood (ML) estimation approach. In a second step we propose novel reparametrizations for two method-of-moments particularly popular in hydrology: the Probability Weighted Moment (PWM) method and its generalized version (GPWM). Finally these three inference methods (ML, PWM and GPWM) are compared and discussed with respect to the issue of correlations.     

浙江庆元古银坑硐群遗迹特征及价值评价

通过对庆元古银坑硐群遗迹的详细调查,查明了该硐群特征。遗迹区共有古矿硐群7处,其中4个规模较大的矿硐长度均在百米以上,最大矿硐共分3层进行开采,垂直落差百米以上。遗迹区内各种规格探采硐保存完整,探矿遗迹数量多,矿业遗迹类型丰富。通过对该遗迹区的价值评价,该矿硐群遗迹可达到国家级矿业遗迹标准。     

A value chain approach to crisis response system: the case of Qingdao

In this paper, we introduce a value chain approach, on the view of the value chain analytic in business management, to be the framework of a crisis response system serving for crisis management strategy in identifying risk sources, responding to unexpected events, and recovering from a shock. This system is not only a computer system but also a system of governmental emergency response mechanism and it is tremendous and complex. The system integrates and coordinates the correlative resources of emergency response units of the city. We consider the efficiency of the system. In addition, the run cost of the system also is taken into account. Based on this framework, the Qingdao’s practical situation is analyzed. As a result, a design proposal of the Qingdao’s crisis response system is put forward.     

地磁转换函数方法之典型震例及数模对比

转换函数零线等值图在2003年新疆伽师-巴楚M_L7.0地震前密集交汇, 震后开始发散, 进一步证实了地磁转换函数方法对预测地震的有效性。 同时, 为适应全国地磁台站的记录数据由模拟向数字化的转变, 对模拟数据和数字化数据从时间序列和转换函数计算结果两方面进行了对比, 为下一步使用数字化数据计算转换函数进行地震预测研究打下了基础。     

黄土高原春季降水对青藏高原感热异常的响应

利用1961—2000年黄土高原56站的春季降水和NCEP/NCAR再分析资料,采用SVD方法分析了黄土高原春季降水与青藏高原地面感热的关系。结果表明,黄土高原春季降水量与青藏高原地面感热的前两个模态代表了两场间的主要耦合特征,具有高度的时空相关。青藏高原感热对黄土高原降水影响最显著的区域在西部和南部、北部。前期高原感热场的第一、二模态对黄土高原春季干旱的预测具有指示意义。     

测井解释中煤层含气量评价方法对比研究

随着煤层气勘探的不断深入,对煤层含气量预测精度提出了更高的要求。基于煤层含气量测井响应特征,分析测井参数与含气量的相关性,提出MIV（Mean Impact Value）技术与LSSVM（Least Squares Support Vector Machine）结合的测井参数优选策略,优选最优测井参数作为网络建模的输入自变量组合,通过粒子群算法优化LSSVM网络核心参数,最后构建一套适用于煤层含气量预测的MIV-PSO-LSSVM模型。在此基础上,分别对比分析LSSVM、PSO-LSSVM、MIV-LSSVM和MIV-PSO-LSSVM模型对煤层含气量的预测性能,并与传统多元回归方法进行了对比,利用拟合优度和均方根误差对此5类模型进行评价。结果表明：PSO优化下的LSSVM模型预测精度得到有效提升,结合MIV方法优选测井参数可大幅度改善神经网络建模性能,MIV-PSO-LSSVM模型可实现煤层含气量高精度预测,为煤层气勘探及其储层评价提供新的技术支撑,且本研究的建模策略及思想可广泛应用于其他机器学习建模研究领域。     

Using value engineering to optimize flood forecasting and flood warning systems: Golestan and Golabdare watersheds in Iran as case studies

Flood occurrence has always been one of the most important natural phenomena, which is often associated with disaster. Consequently, flood forecasting (FF) and flood warning (FW) systems, as the most efficient non-structural measures in reducing flood loss and damage, are of prime importance. These systems are low cost and the time required for their implementation is relatively short. It is emphasized that for designing the components of these systems for various rivers, climatic conditions and geographical settings different methods are required. One of the major difficulties during implementing these systems in different projects is the fact that sometimes the main functions of these systems are ignored. Based on a systematic and practical approach and considering the components of these systems, it would be possible to extract the most essential key functions of the system and save time, effort and money by this way. For instance, in a small watershed with low concentration and small lead time, the main emphasis should be on predicting and monitoring weather conditions. In this article, different components of flood forecasting and flood warning systems have been introduced. Then analysis of the FF and FW system functions has been undertaken based on the value engineering (VE) technique. Utilizing a functional view based on function analysis system technique (FAST), the total trend of FF and FW functions has been identified. The systematic trend and holistic view of this technique have been used in optimizing FF and FW systems of the Golestan province and Golabdare watersheds in Iran as the case studies.     

Entangled exchange: Reconceptualising the characterisation and practice of bodily commodification

Richard Titmuss’ classical 1970 study of blood donation has provided a powerful conceptual model for characterising transactions involving human bodily materials. This now paradigmatic model suggests that such transactions are typically organised in accordance with one or other of two dichotomous, and mutually exclusive, modes of exchange: gifting or commodification. In this paper I utilise findings from my own and others’ empirical research to illustrate the range of complex, multiply constituted, and contested modes of commodification that now typically attend the exchange of human body parts and tissues of which Titmuss’ model can take no effective account. Drawing on work by Radin, Callon, and Miller I illustrate the complex justificatory work that those involved must perform to fit their lived experiences of tissue exchange into this now outmoded paradigm. I then consider how the protagonists themselves ontologise their practices and with what effects. In the second part of the paper I consider how neo-liberal ideologies and instruments are being employed to suborn a variety of highly differentiated and geographically distinct practices of bodily commodification to the ‘logic of the market’. I explore here what the operative effects of defining the global circulation of body parts and tissues as a new ‘economy’ might be. I then consider how, if at all, a market logic could ‘Value’ all those ‘calculations of interest’ and ‘values’ that underpin exchanges of human body parts and tissues in specific national, communal or institutional settings. I conclude by reflecting on the desirability or possibility of performing normative assessments of the ethicacy of highly geographically and culturally differentiated practices of bodily commodification.     

Family ties,preconceived images and trust: How local community defines market collaboration in the Dutch fish chain

Vertical chain collaboration is a strategy for customers’ value creation. However, Dutch fishermen are hardly participating in integrated value chains. While supply chain literature describes factors that contribute to successful chain partnerships, scarce research has been done on the dynamics of the sociocultural context for chain collaboration.In 10 semi-structured interviews, representatives of supply chain parties were asked for their perceptions on chain collaboration, trust, and the role of the local community. The interviews were directed at obtaining so-called ‘tacit’ knowledge, the non-spoken codified truths of social networks. Without generalizing, this research provides benchmarks to monitor how the different domains, laid out in this study, impact chain collaboration: community values, network participation and company competences. An overview is given of socio-economic factors blocking and enhancing chain collaboration at company and community level. Factors such as the strong bonding of family with business in tightly knit networks, a high level of social control, entrepreneurial autonomy, and loyalty as community norm hamper collaboration within the supply chain.Respondents’ discourse demonstrates that cultural codes and identity form the very core of the entrepreneur, driving rather than ‘embedding’ economic behavior. Kinship, religion and peer pressure determine ‘windows on the world’ when engaging in chain collaboration. Consequently, any analysis of economics that does not integrate sociological and psychological methodology is flawed from the outset.     

线性最小二乘问题的正则化方法

本文讨论一类求解线性最小二乘问题的正则化方法的可行性。给出两条较为实用的可行性检验准则,推广了经典的Greville定理。