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1.
Scientific insights into what it means to manage on-farm trees by local farmers, is an essential step towards documenting local ecological knowledge for sustainable landscape management. A study was therefore conducted in the Kumawu Forest District in the Ashanti Region of Ghana to assess how farmers conceptualise on-farm tree management and develop local knowledge for it. Using a case study approach, data were collected through informal interviews and focus group discussions with 120 farmers drawn from 15 communities who were involved in the management of three cropping systems; cocoa, maize and cassava-cocoyam-plantain mix. It was observed that the farmers regard on-farm tree management as a continuous process which occurs in three phases of the farming cycle; land preparation, crop cultivation and fallow management. For each of the three phases, farmers are guided by specific principles that ensure enough light penetration in-between tree crowns in the land preparation phase, suitable spacing between trees and crops in the crop cultivation phase and adequate tree regeneration in the fallow phase. The decisions made during the selection of tree species, spacing of trees adjudged suitable for any particular cropping system and recruitment of saplings prior to the fallow phase of farming constitute tree management. Farmers develop tree management knowledge by studying the physical characteristics of species, matching them to ecological functions they could perform and how they are likely to respond to treatments meant to control or enhance their development. Species are then subjected to trial and recommended or otherwise.  相似文献   
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Recognizing that supervisor–subordinate dyads exist within a broader organizational hierarchy, we examine how the individual's role within the organizational hierarchy influences perceptions of abusive supervision. Specifically, we examine how supervisors' abusive behaviors are perceived by abusive supervisors' managers as well as abusive supervisors' subordinates. Drawing on role theory, we propose that these perceptions will differ. Further, we suggest that these differences will be reflected in different relationships between manager-rated abusive supervision and subordinate-rated abusive supervision and managers' evaluations of supervisor performance. Results from manager–supervisor–subordinate triads indicate differences between managers' and subordinates' view of abusive supervision. Further, managers' perceptions of abuse were related to supervisors' in-role performance, whereas subordinates' perceptions of abuse were related to workgroup performance. In Study 2, we replicate these findings and expand our investigation to an examination of supervisors' contextual performance. Additionally, we examine another contextual characteristic—aggressive climate—and demonstrate it influences how abusive supervision relates to managerial evaluations of supervisor performance. Future research and managerial implications are discussed.  相似文献   
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This paper analyses the contribution of virtue ethics, the study of good character traits, to the humanitarian context. It argues that a virtue ethics perspective paints a realistic picture of the use of ethical standards in morally complex circumstances. Virtuous relief workers can employ standards in their thinking, but they are also committed to professional excellence that goes beyond any formal code. The concept of virtue ethics places a stress on moral development, which can be facilitated by role models that impart modest and feasible ideals. However, virtue ethics cannot provide simple guidelines on how to resolve difficult situations. It is possible that two virtuous persons can disagree on what should be done in a particular instance. In addition, a virtue ethics perspective emphasises the need for both individuals and organisations to discuss the actual purpose of relief work in order to pinpoint the virtues of a good relief professional.  相似文献   
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目的为了更好地解决高超声速飞行器舵、翼前缘及头锥等气动热环境恶劣区域的热防护问题。方法采用主动式热疏导技术,以高温液态合金为工质,设计并制作具有主动式热疏导功能的尖化前缘金属试验模型(R=5 mm)。根据模型外尺寸设计加工一套石英灯仿形加热器和热流测试模型,开展地面热环境模拟试验。结果试件在前缘中心温度530℃左右时具有瞬态启动特性。前缘中心和大面积中心最大辐射热流密度分别为1000 kw/m^2和580 kw/m^2,试件在该环境中长时间受热状态下仍具有较好的热疏导能力。试验后试件无工质泄漏和结构破坏,具有一定的可重复使用性。结论可以此热疏导方式结合现有成熟热防护技术进一步开展工程设计与应用。  相似文献   
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污染场地是工业化发展的产物,中国的污染场地修复与管理尚处于起始阶段,如何实现国家层面对污染场地的有效监管是一个重要课题。在国家污染场地信息管理数据库框架基础上,提出了以流程管理(BPM)架构技术和业务流程引擎技术为基础构建支持跨平台和跨系统的数据采集、处理和分析的BPM运行平台,设定了污染场地管理的主要机构和相应主要角色,还设计了污染场地资料入库和分类评估的管理流程,以期为中国污染场地的计算机化和网络化监管平台建设提供参考和借鉴。  相似文献   
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介绍了侧吸导烟技术的技术背景,分析计算了焦炉装煤烟尘成分及含量,经对该技术的经济效益进行概算后显示,该技术可以有效改善焦炉区及周边环境,每年还可创造可观的经济效益,是一项值得研究推广的技术。  相似文献   
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《组织行为杂志》2017,38(5):650-670
We theorized and examined a Pygmalion perspective beyond those proposed in past studies in the relationship between transformational leadership and employee voice behavior. Specifically, we proposed that transformational leadership influences employee voice through leaders' voice expectation and employees' voice role perception (i.e., Pygmalion mechanism). We also theorized that personal identification with transformational leaders influences the extent to which employees internalize leaders' external voice expectation as their own voice role perception. In a time‐lagged field study, we found that leaders' voice expectation and employees' voice role perception (i.e., the Pygmalion process) mediate the relationship between transformational leadership and voice behavior. In addition, we found transformational leadership strengthens employees' personal identification with the leader, which in turn, as a moderator, amplifies the proposed Pygmalion process. Theoretical and practical implications are discussed. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
9.
Overqualification denotes situations in which job incumbents have higher qualifications than those required for the job. Drawing on the self‐regulatory perspective, we proposed that employees' perception of overqualification positively affects their proactive behavior through the mechanism of role‐breadth self‐efficacy and that this indirect effect is moderated by employees' goal orientations. We tested our hypotheses through two studies. In Study 1, we found that perceived overqualification had a positive indirect effect on employees' proactive behavior through role‐breadth self‐efficacy using a sample of 323 salespeople with a cross‐lagged panel design. In Study 2, the multi‐wave and multi‐source data from 302 teachers confirmed the indirect effect and indicated that performance goal orientation and learning goal orientation moderated the indirect relationship. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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