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161.
162.
In order to investigate the role of functional groups present in humic acid(s) (HA) during complex formation, water soluble complexes between HA isolated from soil and metals (Pb, Ca, As, Ni, Cr, Co, Cu, Cd, Fe, Mn, Mg and Zn) were prepared and subjected to infrared (IR) spectroscopy. the IR data revealed the involvement of the - OH group of humic acid in complex formation with all metals except copper and arsenic, whereas the - COOH group of HA was found to be the preferred site of binding for all the metals. the significance of findings in relation to detoxification of environmental pollutants is discussed in this paper.  相似文献   
163.
The governance of knowledge is a crucial element of ecosystem-based management (EBM) and is deemed important for its effectiveness. In this paper we analyze from an empirical perspective how the governance of knowledge in different EBM practices is organized and with what consequences. Based upon four different case studies – all derived from the Wadden Sea – which resemble different contexts (in terms of available knowledge and level of conflict) we reconstruct four different ways of knowledge governance. These four approaches are labeled the database, the alignment, the assessment and the holistic approach. These approaches differ in how the interaction between knowledge production and decision-making is organized. They show different degrees of success, partly related to the extent to which they fit in the context in which they are applied. Understanding the differences in contexts in which knowledge for EBM has to be organized, can help decision-makers to apply the most suitable way of knowledge governance in their specific case. In cases of low conflict and high knowledge capacity a more static, one-directional way of knowledge governance can suffice, while in more complex contexts a holistic approach seems to be necessary.  相似文献   
164.
165.
Recent research suggests that monitoring key events in social, economic, cultural and political systems may provide more timely, frequent, and reliable warnings of impending famine than monitoring physical processes alone. But empirical data on early warning distress signals in these arenas are slim. Based on anthropological investigations in a southern Volta Noire community of Burkina Faso (formerly Upper Volta) during the drought of 1983–1984, this paper outlines a variety of possible early warning signals in disposal systems for staple foodgrains - the nutritional “bottom line” for farmers and herders in the West African savannah. Pre-famine distress signals in five broad categories are discussed: changes in marketing patterns, non-market exchanges, dietary practices, utilization of agricultural and pastoral labour, and ideological and sociopolitical behaviours. Data consist of both quantitative and qualitative comparisons of cereal disposals in these categories between 1983 and preceding years.  相似文献   
166.
Modern work is frequently characterized by jobs where adaptive performance (AP) is crucial for employees to succeed in light of new or altered task demands. This recognition has fueled growing interest in AP as a dimension of workplace performance. To this point, however, research on AP has evolved from disparate perspectives and methods, resulting in fragmentation and a less than coherent knowledge base. This paper presents a comprehensive review of research studies regarding the nomological network of individual AP. In doing so, we synthesize the current knowledge base surrounding correlates of AP, elucidate current ambiguities, and suggest directions for future research efforts. We conclude that although the extant AP literature has amassed a critical body of studies linking various predictors to successful AP outcomes, much remains unknown, most critically regarding the implications of different methods of assessing AP, the effects of different types of changes in the task environment, the process of AP, and the steps organizations can take to foster AP among their employees. We hope that our synthesis and analysis paves the way for efforts to address these important questions. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
167.
根据矿井风流调节的具体要求,合理选择矿用空气幕的型号是应用矿用空气幕技术的关键。在分析矿用空气幕选型依据及原理的基础上,应用矿井通风三维仿真系统软件模拟矿用空气幕运行的效果,来研究确定矿用空气幕的选型参数及影响因素。结果表明,应用矿井通风三维仿真系统软件所选择的矿用空气幕与理论推导的计算结果一致,此方法能够最大限度地反映矿山实际情况,具有直观、高效等特点。  相似文献   
168.
Adaptive co-management and learning are paramount for integrated flood risk management. Relevant literature focuses on adaptation at the level of physical and societal systems. The level of projects and programmes is largely overlooked, but they comprise interventions that adapt our physical systems and they provide opportunities for learning to contribute to transitions of societal systems. This paper aims to increase understanding on how learning takes place and can be stimulated within a programme. The mixed-method case study of Room for the River, a €2.3 billion programme for flood risk management, shows that a programme can be organised using various governance arrangements to stimulate learning and be a means for adaptive co-management to deliver upon environmental objectives.  相似文献   
169.
In the last two decades, several serious accidents at large-scale technological systems that have had grave consequences, such as that at Bhopal, have primarily been attributed to human error. However, further investigations have revealed that humans are not the primary cause of these accidents, but have inherited the problems and difficulties of working with complex systems created by engineers. The operators have to comprehend malfunctions in real time, respond quickly, and make rapid decisions to return operational units to normal conditions, but under these circumstances, the mental workload of operators rises sharply, and a mental workload that is too high increases the rate of error. Therefore, cognivitive human features such as situation awareness (SA)—one of the most important prerequisite for decision-making—should be considered and analyzed appropriately. This paper applys the SA Error Taxonomy methodology to analyze the role of SA in three different accidents: (1) A runaway chemical reaction at Institute, West Virginia killing two employees, injuring eight people, and requiring the evacuation of more than 40,000 residents adjacent to the facility, (2) The ignition of a vapor cloud at Bellwood, Illinois that killed one person, injured two employees, and caused significant business interruption, and (3) An explosion at Ontario, California injuring four workers and caused extensive damage to the facility. In addition, the paper presents certain requirements for cognitive operator support system development and operator training under abnormal situations to promote operators’ SA in the process industry.  相似文献   
170.
Adaptation takes place in both private and public sectors, or as an interrelation between the two, and often under the realm of public regulation. Thispaper uses the Swedish and the Norwegian electricity grid sector, as providers of a vital public good under strict public regulation, to analyse reforms' effects on adaptive capacity in this area. The paper shows that transformational changes in both sectors during the 1990s shifted both the formal organisational structure (rules and regulations), as well as the organisational culture, in the direction of economic efficiency. These two dimensions individually reduced adaptive capacity to climate change, although differently in the two countries. However, the formal structure and organisational culture also yielded substantial influence on each other. This leads to the conclusion that when designing public regulations and implementing reforms, organisational culture must be considered in the design. Also the paper contests previous findings in the literature by showing that under given conditions there exist some substitution between the two dimensions in influencing adaptive capacity, implying that both dimensions should be included when analysing adaptation since analysing them in isolation is likely to lead to wrong conclusions.  相似文献   
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