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Systems engineering principles in fisheries management may structure and improve the decision-making process. Sustainability in the fishing fleet is comprised of economic, environmental, and social dimensions. Even though the total system value may be constituted by economic factors and technical factors, non-market issues, such as environmental and social issues, have an increasingly important impact on the economic performance of a system or company. Life cycle cost (LCC) is related to the systems engineering process, because economic considerations are very important in the process of creating systems. LCC involves evaluation of all future costs related to the life cycle of a system. The main objective of this article is to discuss the usefulness of LCC as a method to enhance sustainable designs of fishing vessels for ship owners, and to improve the decision-bases for fisheries management.  相似文献   
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An interaction effect indicates that a relationship is contingent upon the values of another (moderator) variable. Thus, interaction effects describe conditions under which relationships change in strength and/or direction. Understanding interaction effects is essential for the advancement of the organizational sciences because they highlight a theory's boundary conditions. We describe procedures for estimating and interpreting interaction effects using moderated multiple regression (MMR). We distill the technical literature for a general readership of organizational science researchers and include specific best‐practice recommendations regarding actions researchers can take before and after data collection to improve the accuracy of MMR‐based conclusions regarding interaction effects. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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The West African Sahel is a harsh environment stressed by a fast-growing population and increasing pressure on the scarce natural resources. Agriculture is the main source of livelihood of the majority of the people living in the area. Increases in temperature and/or modifications in rainfall quantities and distribution will substantially impact on the natural resource on which agriculture depends. The vulnerability of livelihoods based on agriculture is increased and most likely exacerbate and accelerate the current ‘downward spiral’ of underdevelopment, poverty and environmental degradation. Notably, droughts, a short rainy season and/or very low rainfall will be felt by current systems. To cope with the difficult climatic situation, farm households have developed a range of strategies including selling of animals and on-farm diversification or specialization. At regional level, early warning systems including an operational agro-meteorological information system already provide farmers with crucial information. Substantial political, institutional and financial efforts at national and international level are indispensable for the sustenance of millions of lives. In terms of development, priority needs to be given to adaptation and implementation of comprehensive programs on water management and irrigation, desertification control, development of alternative sources of energy and the promotion of sustainable agricultural practices by farmers.  相似文献   
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Particulate matter (PM) has become a major research issue receiving increasing attention because of its significant negative impact on human health. There are main indicators that next to the morphological characteristics of the particle, also the chemical composition plays an important role in the adverse health effects of PM. In this context, the rather polar organic fraction of PM is expected to play a major role, and advanced analytical techniques are developed to improve the knowledge on the molecular composition of this fraction. One component class that deserves major attention consists of the oxygenated polycyclic aromatic hydrocarbons (PAHs). Those compounds are considered to be among the key compounds in PM toxicity. This paper presents a comprehensive review focusing on the analysis, fate and behavior of oxygenated PAHs in the atmosphere. The first part of the paper briefly introduces (i) the main sources and atmospheric pathways of oxygenated PAHs, (ii) available physical–chemical properties and (iii) their health effects. The second and main part of this paper gives a thorough discussion on the entire analytical sequence necessary to identify and quantify oxygenated PAHs on atmospheric PM. Special attention is given to critical parameters and innovations related to (i) sampling, (ii) sample preparation including both extraction and clean-up, and (iii) separation and detection. Third, the state-of-the-art knowledge about the atmospheric occurrence of oxygenated PAHs is discussed, including an extended overview of reported concentrations presented as a function of sampling season and geographical location. A clear seasonal effect is observed with the median of the oxygenated PAHs concentrations during winter being a factor of 3–4 higher than during summer. However, the oxygenated PAH/parent PAH ratio is about 20 times higher during summer, indicating the importance of photochemical activity in the atmosphere.  相似文献   
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There is a science‐practice gap in organizational behavior (OB) whereby entire bodies of scholarly knowledge are ignored by practitioners. We identify research needed to improve performance management practices that is likely to enhance the relevance of OB in the eyes of practitioners and thus help reduce the science‐practice gap. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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