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501.
有效的在线过程诊断是实现厌氧水处理工艺稳定运行的必要手段。基于在线监测数据,通过整合反应器气相液相重要参数,建构了一对新型状态评估指标,稳定性指标S以及辅助指标a。评估指标可以对厌氧反应器状态进行全面定量的诊断,也可以对过程潜在不稳定性进行早期预警。通过对厌氧反应器进行多种类型冲击实验(有机负荷、HRT、温度和毒物),测试了指标对各种冲击状态的响应,实验结果表明新型指标可以对反应器状态进行准确快速的在线诊断。作为诊断方法的核心,指标对厌氧工艺的过程评估具有高精度和高灵敏性,并且特别适用于智能化的在线诊断和自动控制。 相似文献
502.
破坏性地震发生后,快速高效地开展地震应急工作离不开地震应急技术的基础支撑。为进一步掌握我国地震应急技术现状,持续增强我国应急能力,通过梳理现阶段我国地震应急指挥、地震烈度调查与损失评估、地震现场流动监测3大技术系统,从技术构成、技术功能、存在问题等方面探讨我国现有地震应急技术。结果表明:现阶段我国的地震应急技术发展显著,但仍存在不足和薄弱环节,标准化、智能化、综合化或将成为新方向。 相似文献
503.
A central argument in the literature on employee voice is that speaking up at work carries image risk. Challenging this assumption, we propose that voice can in fact positively affect how employees are viewed by others, thereby enhancing their social status. Using theory on status attainment and the fundamental social perception dimensions of agency and communion, we suggest that employee voice will result in higher status evaluations by increasing the extent to which an employee is judged as confident/competent (agency) and other‐oriented/helpful (communion). We conducted a survey study and two experiments to test these hypotheses. The results supported our predictions. Employees who voiced were ascribed higher status than those who did not, and this effect was mediated by judgments of agency (in all three studies) and communion (in two studies). These results highlight the implications of voice behavior for status enhancement within organizations. 相似文献
504.
通过检索在国内外期刊发表的文献中关于我国河流、湖泊中氯胺酮(KET)的数据,评估其在地表水中的暴露水平,利用风险商(RQ)初步分析KET在我国部分地表水环境中的生态风险。结果表明,我国地表水中KET的检出率为20%~100%,最高检出值为420 ng/L,基于发育、繁殖和行为等慢性毒性数据推导出的预测无效应浓度(PNEC)为1.36×10-6mg/L;基于慢性毒性计算的风险商值为0.03~36.76,表明我国地表水中KET存在风险,其中台湾淡水河、金梅河和广东珠江具有高风险,而北方大部分河流潜在风险较低。 相似文献
505.
Medilanski E Chuan L Mosler HJ Schertenleib R Larsen TA 《Environmental management》2007,39(5):648-662
We conducted a study of the institutional barriers to introducing urine source separation in the urban area of Kunming, China.
On the basis of a stakeholder analysis, we constructed stakeholder diagrams showing the relative importance of decision-making
power and (positive) interest in the topic. A hypothetical decision-making process for the urban case was derived based on
a successful pilot project in a periurban area. All our results were evaluated by the stakeholders. We concluded that although
a number of primary stakeholders have a large interest in testing urine source separation also in an urban context, most of
the key stakeholders would be reluctant to this idea. However, the success in the periurban area showed that even a single,
well-received pilot project can trigger the process of broad dissemination of new technologies. Whereas the institutional
setting for such a pilot project is favorable in Kunming, a major challenge will be to adapt the technology to the demands
of an urban population. Methodologically, we developed an approach to corroborate a stakeholder analysis with the perception
of the stakeholders themselves. This is important not only in order to validate the analysis but also to bridge the theoretical
gap between stakeholder analysis and stakeholder involvement. We also show that in disagreement with the assumption of most
policy theories, local stakeholders consider informal decision pathways to be of great importance in actual policy-making. 相似文献
506.
Since 1949, China has witnessed four development stages of territorial planning. (1) In the 1950s the territorial planning got its start. (2) From the 1960s to 1970s territorial planning declined. (3) From, the 1980s to 1990s the first major tide of territorial planning began. (4) From the end of the 1990s to recent times the new round of territorial planning is under deliberation. Since 1998, the Ministry of Land and Resources has carried out some related work, especially in organizing pilot projects, and early research on the new round of national territorial planning. According to the need for economic and social development and the current conditions in China, it is the appropriate for China to carry out the new round of territorial planning. However, the government should correctly consider the correlations between territorial planning and other plan- nings, and take appropriate development action, e.g. stressing main points for the basis of overall planning, building a territorial planning system that coordinate with national conditions, strengthening research on various supportive measures of territorial planning, summarizing and upgrading experiences obtained in pilot projects, strengthening international exchange and training talented personnel. 相似文献
507.
508.
Different criteria have been proposed for the rapid ecological evaluation of wooded areas. It is difficult, however, to determine the criteria most likely to yield results similar to those that would be obtained through detailed surveys and exhaustive evaluation. In order to identify such synthetic criteria, data from a detailed evaluation of Montreal Urban Community woodlots were studied with the help of multivariate analysis. This detailed evaluation was undertaken at two levels—woodlot unit and the woodlots themselves—using 16 different criteria.At the woodlot unit level, area and abundance indices of shade intolerant species in the tree layer could be used as synthetic criteria, while at the woodlot level the ecological value of the constituent units stand out as the first synthetic criterion. These results are compared with criteria proposed in the literature, and the use of multivariate analysis in ecological evaluation is briefly discussed. 相似文献
509.
Daniel B. Fitzgerald David R. Smith David C. Culver Daniel Feller Daniel W. Fong Jeff Hajenga Matthew L. Niemiller Daniel C. Nolfi Wil D. Orndorff Barbara Douglas Kelly O. Maloney John A. Young 《Conservation biology》2021,35(5):1627-1638
Many questions relevant to conservation decision-making are characterized by extreme uncertainty due to lack of empirical data and complexity of the underlying ecologic processes, leading to a rapid increase in the use of structured protocols to elicit expert knowledge. Published ecologic applications often employ a modified Delphi method, where experts provide judgments anonymously and mathematical aggregation techniques are used to combine judgments. The Sheffield elicitation framework (SHELF) differs in its behavioral approach to synthesizing individual judgments into a fully specified probability distribution for an unknown quantity. We used the SHELF protocol remotely to assess extinction risk of three subterranean aquatic species that are being considered for listing under the U.S. Endangered Species Act. We provided experts an empirical threat assessment for each known locality over a video conference and recorded judgments on the probability of population persistence over four generations with online submission forms and R-shiny apps available through the SHELF package. Despite large uncertainty for all populations, there were key differences between species’ risk of extirpation based on spatial variation in dominant threats, local land use and management practices, and species’ microhabitat. The resulting probability distributions provided decision makers with a full picture of uncertainty that was consistent with the probabilistic nature of risk assessments. Discussion among experts during SHELF's behavioral aggregation stage clearly documented dominant threats (e.g., development, timber harvest, animal agriculture, and cave visitation) and their interactions with local cave geology and species’ habitat. Our virtual implementation of the SHELF protocol demonstrated the flexibility of the approach for conservation applications operating on budgets and time lines that can limit in-person meetings of geographically dispersed experts. 相似文献
510.
Basic Principles and Ecological Consequences of Altered Flow Regimes for Aquatic Biodiversity 总被引:42,自引:2,他引:42
The flow regime is regarded by many aquatic ecologists to be the key driver of river and floodplain wetland ecosystems. We
have focused this literature review around four key principles to highlight the important mechanisms that link hydrology and
aquatic biodiversity and to illustrate the consequent impacts of altered flow regimes: Firstly, flow is a major determinant
of physical habitat in streams, which in turn is a major determinant of biotic composition; Secondly, aquatic species have
evolved life history strategies primarily in direct response to the natural flow regimes; Thirdly, maintenance of natural
patterns of longitudinal and lateral connectivity is essential to the viability of populations of many riverine species; Finally,
the invasion and success of exotic and introduced species in rivers is facilitated by the alteration of flow regimes. The
impacts of flow change are manifest across broad taxonomic groups including riverine plants, invertebrates, and fish. Despite
growing recognition of these relationships, ecologists still struggle to predict and quantify biotic responses to altered
flow regimes. One obvious difficulty is the ability to distinguish the direct effects of modified flow regimes from impacts
associated with land-use change that often accompanies water resource development. Currently, evidence about how rivers function
in relation to flow regime and the flows that aquatic organisms need exists largely as a series of untested hypotheses. To
overcome these problems, aquatic science needs to move quickly into a manipulative or experimental phase, preferably with
the aims of restoration and measuring ecosystem response. 相似文献