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991.
In this study, ten bioenergy crop rotations (corn, corn-stover, sorghum, soybean, corn-soybean, corn-soybean-canola, corn-stover-soybean, miscanthus, switchgrass, and sorghum-soybean) were selected based on local stakeholder (economically motivated) and regulator (environmentally motivated) preferences. These crops were implemented on diverse landscapes (agricultural, marginal, and agricultural plus marginal lands) one at time for 17 years using a SWAT model of the Saginaw River Watershed in Michigan. The bioenergy crops were evaluated based on 100 percent, 50 percent, and zero percent weight assigned to both stakeholders’ and regulators’ preferences using analytic hierarchy process (AHP), an optimization and decision-making technique that aims to satisfy multiple conflicting objectives. The corn-soybean-canola rotation was selected in all landscapes based on economic benefits (stakeholders’ preferences). Meanwhile, perennial grasses (miscanthus and switchgrass) were selected based on environmental benefits (regulators’ preferences), because they maintain permanent cover, require fewer inputs than traditional row crops, and are less management intensive. When implementing bioenergy crops on marginal lands, pollution generation greatly increased at the field level, indicating that these lands are likely not viable for bioenergy crop production to meet potential future renewable energy demand.  相似文献   
992.
Landscape is defined by the European Landscape Convention as “an area perceived by people, whose character is the result of the action and interaction of natural and/or human factors”. Many efforts have been devoted in addressing the core concepts on which this definition roots: perception and interaction of men and nature, but when coming to large (continental) scale assessments, the latter prevail on the former.This paper aims at presenting a framework for a measurable landscape awareness indicator as a key link to the public demand for a specific type of landscape: the agricultural landscape. This is a necessary effort to complement more physically based assessments, which include as well the impact of human activities on landscapes.The analysis is carried out at different levels of governance: EU and regional, using an example from the Alentejo region in Portugal and EU wide databases, and addresses conceptual and practical questions: what type of societal landscape awareness can be monitored and by whom (e.g., individuals, specific social groups, society as a whole); what are the landscape dimensions that should be assessed; what are the limitations imposed by data-related constraints. By applying the methodology to build composite indicators to map landscape societal awareness, the paper shows the regional and local meaning of indicator approaches developed at European level, presents developments for downscaling to regional level, while introducing the social component to support sound policy development for European rural landscapes.  相似文献   
993.
本文在对食品机械安全卫生设计问题研究过程中,立足于实际工作情况,从自身工作经验角度出发,分析食品机械安全卫生设计的相关内容,重点从食品加工和机械安全方面出发,探讨其设计的基本内容。  相似文献   
994.
995.
Researchers have spent substantial effort to identify factors influencing pesticide use intensity. However, few studies have compared the relative importance of these factors. This study examines four categories of factors that potentially influence farmers’ pesticide use decisions by evaluating incentivized experiment data, farm survey data, and remote sensing data in China. Our results suggest that land diversification has the largest effect on farmers’ pesticide use. Compared with the most rice-intensive landscape type, less rice-intensive systems cause farmers to spray less on middle rice. Heavy pesticide use intensity is associated with land fragmentation as small-scale farms still dominate crop production. Farmers’ integrated pest management knowledge has significant effects on pesticide use. We also find that loss and ambiguity preferences, rather than risk preferences, are more likely to affect pesticide use intensity.  相似文献   
996.
民办高校党务干部队伍作为学校党建工作实施者,其队伍状况在很大程度上将直接影到党建工作质量和水平,进而影响到人才培养质量。目前民办高校党务干部队伍普遍存在队伍结构失衡,党务干部身兼多职,重业务知识学习,轻理论武装,重专业技能培训轻党务能力提升等状况。要改善现状,必须做到:一是加强制度建设,狠抓贯彻落实,争取上层支持;二是加强业务培训,鼓励开展党建工作研究;三是加强党建工作信息化建设,打造符合时代需求的党务干部队伍;四是引进激励措施,提高工作积极性。  相似文献   
997.
项目的价值工程方法是一种以实现项目利益相关各方最高满意度的创造性活动,在规划设计阶段,价值工程对项目价值有决定性的影响。因此,在项目前期,应积极应用价值工程的方法进行多方案的比选分析,以达到项目价值的最大化目的。  相似文献   
998.
We present a novel lens on the presence and impact of qualified foreign institutional investors (QFII) in top shareholdings of the non-financial domestically listed Chinese ‘A’ share firms. The initial results suggest that the presence of a QFII as a top shareholder in these companies is associated with their better performance, using both Tobin’s Q and ROA as the performance measures. Our models include variables representing corporate governance mechanisms, foreign legal person shares, a proxy for international affiliations and a number of time-variant firm characteristics. Economically, the coefficient of impact on the market measure is the more significant, while the effect of having a QFII in top shareholdings on both performance measures is empirically significant. Previously, studies have often ignored the potential for reverse causality beyond using lagged regressors. This is problematic. Therefore, we follow up with a 2SLS instrumental variables and system GMM model to further mitigate this potential and find the empirical relationship holds. Contrary to earlier work on QFIIs and governance post-implementation of the QFII scheme, the findings from our models suggest that the presence of a QFII top shareholder augments market performance holding equal existing corporate governance mechanisms and other controls.  相似文献   
999.
This study uses the structure–conduct–performance framework to examine the structure and efficiency of small and medium enterprises in the informal metal manufacturing sector in Zimbabwe. Small and medium enterprises provide a lifeline to the country's resource-poor farmers, whose numbers increased exponentially after the agrarian reform in 2000. The study utilises nationally representative, enterprise-level data from five major towns (Harare, Chitungwiza, Bulawayo, Mutare and Rusape) in Zimbabwe. Various performance measures are applied at the industry level to assess efficiency, profitability and competitiveness; these include the Herfindahl–Hirschman index, concentration ratios, average yearly profits and Tobin's q ratio. The results indicate that small and medium enterprises in Zimbabwe are modestly efficient, profitable and competitive. These findings highlight the need to integrate informal metal fabrication activities into Zimbabwe's national economic development plans.  相似文献   
1000.
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