AN EARLY WARNING SYSTEM FOR DROUGHT MANAGEMENT USING THE PALMER DROUGHT INDEX1

ABSTRACT: The Palmer Drought Severity Index (PDSI) is used in a non-homogeneous Markov chain model to characterize the stochastic behavior of drought. Based on this characterization an early warning system in the form of a decision tree enumerating all possible sequences of drought progression is proposed for drought management. Besides yielding probabilities of occurrence of different drought severity classes, the method associates a secondary measure in terms of likely cumulative precipitation deficit to provide timely guidance in deciding drought mitigation actions. The proposed method is particularly useful for water availability task forces in various states for issuing drought warnings in advance. The applicability of the technique is illustrated for the Tidewater climatic division of Virginia.     

环境价值链分析在钢铁行业的应用

提出一种环境价值链分析方法,以英国钢铁物流为例进行环境价值链分析,并对我国钢铁行业价值链问题进行分析,结果发现:价值链分析是一种有活力的方法,在探索经济-环境交界面的多种方法中,是物流分析和生命周期分析的一种有利的补充,很有可能被广泛应用。     

Economic Growth and Marine Biodiversity: Influence of Human Social Structure on Decline of Marine Trophic Levels

Abstract:  We assessed the effects of economic growth, urbanization, and human population size on marine biodiversity. We used the mean trophic level (MTL) of marine catch as an indicator of marine biodiversity and conducted cross-national time-series analyses (1960–2003) of 102 nations to investigate human social influences on fish catch and trends in MTL. We constructed path models to examine direct and indirect effects relating to marine catch and MTL. Nations' MTLs declined with increased economic growth, increased urbanization, and increased population size, in part because of associated increased catch. These findings contradict the environmental Kuznets curve hypothesis, which claims that economic modernization will reduce human impact on the environment. To make informed decisions on issues of marine resource management, policy makers, nonprofit entities, and professional societies must recognize the need to include social analyses in overall conservation-research strategies. The challenge is to utilize the socioeconomic and ecological research in the service of a comprehensive marine-conservation movement.     

Efficient implementation of the Metropolis-Hastings algorithm,with application to the Cormack–Jolly–Seber model

Judicious choice of candidate generating distributions improves efficiency of the Metropolis-Hastings algorithm. In Bayesian applications, it is sometimes possible to identify an approximation to the target posterior distribution; this approximate posterior distribution is a good choice for candidate generation. These observations are applied to analysis of the Cormack–Jolly–Seber model and its extensions.     

食品工业废渣以发酵技术生产菌体蛋白饲料的研究

为了将食品工业废渣中可被微生物利用的营养物质构成蛋白质的微生物菌体,采用以固态发酵法生产蛋白饲料。试验结果表明,通过组合菌株,在2t规模的发酵池里进行连续培养,较佳的控制工艺条件是：培养温度30℃,培养基初始水份65％,培养时间80h,产品的菌体蛋白达到了30％以上,粗纤维含量下降60％以下,废渣中灰分降低了30％以上,钙和磷分别提高了70％和205倍,并含有丰富的纤维素酶,提高了食品工业废渣的利用价值。     

餐厨垃圾水热炭化产物分配规律及液固产物特性研究

以实采餐厨垃圾为对象,探究了3种反应强度("温和"180℃-1h、"中等"220℃-2h和"剧烈"260℃-4h)下餐厨垃圾水热炭化三相产物分配规律及液固产物特性.结果表明,反应强度显著影响产物分配.随反应强度提升,固相产物(水热炭)产率先上升后下降;液相产物(炭化液)产率先降低后趋于稳定;而气相产物产率持续上升.但无...     

用于废水处理系统中目标酵母动态解析的绿色荧光蛋白基因质粒构建

绿色荧光蛋白(green fluorescent protein,GFP)可用于研究复合微生物体系中特定目标功能菌的特性及动态变化,本研究为确立用于解析酵母细胞在混合酵母废水处理系统中的动态特性的GFP技术体系奠定了基础.将gfp基因克隆到酵母载体pACT-URA3中,再用构建的重组质粒转化宿主菌大肠杆菌(Escherichia coli JMl09),扩增得到含gfp的重组质粒,荧光显微镜照片显示gfp基因在大肠杆菌内得到了表达,但表达程度不高;电泳图谱及聚合酶链反应结果表明,含gfp基因的质粒不是以游离的形式存在,而可能是以某种特殊的形式和细胞染色体发生了相互作用.     

微生物群落对氨胁迫响应的宏基因组学研究

为探析厌氧消化微生物群落对氨胁迫的响应,在串联批次实验中引入氨氮(TAN)胁迫,结合宏基因组学分析,研究了不同TAN浓度下,厌氧消化系统的过程参数、群落结构/组成及其功能基因/代谢途径的响应.结果显示,TAN为3000mg/L时,系统性能逐步优化;TAN为6000mg/L时,甲烷产率逐步下降,并伴随着丙酸、丁酸积累.从...     

宠物食品加工废水处理工程实例

介绍了水解 接触氧化 气浮工艺在宠物食品加工废水中的应用。实践表明 ,在进水CODCr、BOD5和SS分别为 2 5 0 0mg/L、1 6 0 0mg/L和 2 5 0mg/L的情况下 ,出水的CODCr、BOD5和SS分别为 70mg/L、1 5mg/L和 4 0mg/L ,达到了《污水综合排放标准》(GB8978 96 )一级标准。经过 1年半的运行表明 ,该工艺具有运行稳定性好、处理效率高、操作管理方便的优点。     

商业综合体灾害链风险评估研究

为了对商业综合体灾害链进行风险研究,基于链式风险评估模型的建模方法,构建商业综合体灾害链风险评估模型,并应用复杂网络结构对商业综合体灾害链的演化过程进行表征,综合灾害事件的致灾率、灾害损失程度、灾害链的脆弱度3个指标得到每条灾害链的风险度量值,最后以泸州摩尔玛商场爆炸事件为实例进行评估,辨识出每条灾害链的风险值。研究结果表明:该模型与实际情况具有较高的吻合性,为商业综合体次生或衍生灾害的防控提供了可靠的理论依据。