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91.
Scenario‐based and scenario‐neutral impacts assessment approaches provide complementary information about how climate change‐driven effects on streamflow may change the operational performance of multipurpose dams. Examining a case study of Cougar Dam in Oregon, United States, we simulated current reservoir operations under scenarios of plausible future hydrology. Streamflow projections from the CGCM3.1 general circulation model for the A1B emission scenario were used to generate stochastic reservoir inflows that were then further perturbed to simulate a potentially drier future. These were then used to drive a simple reservoir model. In the scenario‐based analysis, we found reservoir operations are vulnerable to climate change. Increases in fall and winter inflow could lead to more frequent flood storage, reducing flexibility to store incoming flood flows. Uncertainty in spring inflow volume complicates projection of future filling performance. The reservoir may fill more or less often, depending on whether springs are wetter or drier. In the summer, drawdown may occur earlier to meet conservation objectives. From the scenario‐neutral analysis, we identified thresholds of streamflow magnitude that can predict climate change impacts for a wide range of scenarios. Our results highlight projected operational challenges for Cougar Dam and provide an example of how scenario‐based and scenario‐neutral approaches may be applied concurrently to assess climate change impacts.  相似文献   
92.
In this article, we provide an assessment of comprehensive nutrient management plans (CNMPs) as a tool for addressing nonpoint nutrient and sediment losses from the animal feeding operations (AFOs) in the Ohio River Basin. We employ a macro modeling system to determine the aggregate economic and water quality impacts of CNMP implementation on AFOs in the entire basin. Results of the study indicate that implementing CNMPs on AFOs will help reduce sediment and organic nutrient losses from their current levels at moderate cost. The flexibility inherent in CNMP designs means farmers may be able to achieve water quality and other conservation goals at less cost with CNMPs than with other less flexible policy options.  相似文献   
93.
王元超  颜梅春  张先聪 《资源开发与保护》2012,(2):99-101,166,F0002
采用重庆市主城区2000年和2010年两个时相的TM影像提取城市扩展信息,对影像数据的归一化建筑指数(NDBI)、归一化植被指数(NDVI)和归一化水体指数(NDWI)进行RGB组合增强,再进行决策树分类和减法运算获取研究区扩展信息,发现建筑区面积增加了1.62倍,大部分是由植被区转变而来。其扩张方向受地理影响,南北方向为外延型,东西方向为飞地型。借助统计资料进行精度验证和城市扩展的驱动因素分析发现,区域发展政策、经济增长和人口扩张是主要的影响因素,探讨了对经济增长、城市扩张和人口增长的关系。研究结果表明,以遥感手段监测与研究城市发展变化的趋势是可行和高效的。  相似文献   
94.
Subsea Xmas tree is a vital equipment for offshore oil and gas development. Aiming at the fault mode of subsea Christmas tree system under production conditions, the fault tree of subsea tree system was established, which was transformed into Dynamic Bayesian network, and the reliability and availability of subsea tree system with different repair states are quantitatively analyzed. In this paper, the DBNs are partially verified by the method based on three axes. The results show that the reliability of subsea vertical tree system is slightly higher than that of subsea horizontal tree system. After repair and maintenance, the performance of subsea tree system has been significantly improved, and the improvement of the system performance by preventive maintenance is more obvious. Compared with the perfect repair, the performance of the system with imperfect repair is not significantly reduced. Compared with perfect repair & preventive maintenance, the performance of the system with imperfect repair & preventive maintenance is slightly reduced. In addition, the influence of failure rates and degradation probability on reliability and availability is analyzed. By comparing the influence of failure rates on the system performance of non-maintenance and maintenance, it is found that the change of failure rates has the greatest influence on the reliability and the least influence on the availability of perfect repair & preventive maintenance. By comparing the performance of each component in the subsea tree system, it is found that the failure rates has the most obvious influence on the chock module, and gate valve and tree cap have the most significant influence on the reliability of the system. In order to improve the reliability of subsea tree system, it is necessary to improve the reliability of chock module, gate valve and tree cap.  相似文献   
95.
本文通过从电梯行业的流通各环节进行讨论,介绍各环节涉及主体、各主体存在的问题及各主体间的联系,重点探讨关于在居民公用电梯使用中业主安全主体责任不明晰、未能有效落实的问题.并为如何有效落实业主在电梯安全管理中的主体责任提出几点对策,以期为降低电梯带病运行的可能、最大程度消除潜藏安全隐患提供一定的参考,从而规范电梯行业安全管理.  相似文献   
96.
Abstract: An integrated economic and environmental modeling system was developed for evaluating agro‐environmental policies and practices implemented on large scales. The modeling system, the Comprehensive Economic and Environmental Optimization Tool‐Macro Modeling System (CEEOT‐MMS), integrates the Farm‐level Economic Model (FEM) and the Agricultural Policy Environmental eXtender (APEX) model, as well as national databases and clustering and aggregation algorithms. Using micro simulations of statistically derived representative farms and subsequent aggregation of farm‐level results, a wide range of agricultural best management practices can be investigated within CEEOT‐MMS. In the present study, CEEOT‐MMS was used to evaluate the economic and water quality impacts of nitrogen (N) and phosphorus (P) based manure application rates when implemented on all animal feeding operations in the State of Texas. Results of the study indicate that edge‐of‐field total P losses can be reduced by about 0.8 kg/ha/year or 14% when manure applications are calibrated to supply all of the recommended crop P requirements from manure total P sources only, when compared to manure applications at the recommended crop N agronomic rate. Corresponding economic impacts are projected to average a US$4,800 annual cost increase per farm. Results are also presented by ecological subregion, farm type, and farm size categories.  相似文献   
97.
Herein we develop a means to differentiate between the energy required to expand and the energy required to maintain the economies of cities. A nonlinear model is tested against historical data for two cities, Hong Kong and Singapore. A robust fit is obtained for Hong Kong, with energy for maintenance close to that for growth, while Singapore, with a weaker fit, is growth dominated. The findings suggest that decreases in either of the per unit maintenance or growth demands can simultaneously cause gross domestic product (GDP) and total energy use to increase. Furthermore, increasing maintenance demands can significantly limit growth in energy demand and GDP. Thus, the low maintenance demands for Hong Kong, and especially Singapore, imply that, all other things being equal, GDP and energy use of these cities will continue to grow, though Singapore’s higher energy use for growth means it will require more energy than Hong Kong.  相似文献   
98.
文化对机组资源管理的影响   总被引:1,自引:0,他引:1  
针对国内民航机组资源管理(CRM)及训练中忽视文化的作用和影响的现状,在调研和分析国外CRM与文化影响的基础上,笔者结合国内民航的运行特点,总结、分析了民族文化、组织文化,以及职业文化对机组协作与配合,CRM训练等方面的积极与消极影响,提出中国民航应根据自身的文化特点调整CRM训练的内容和实施方式,并应从3个层面采取措施来提高CRM及其训练的效果,即航空公司CRM训练的设计、实施与评估;飞机制造商在进行驾驶舱人-机界面设计,以及政府部门在对航空器进行适航审定时,应充分识别不同文化的差异、在强化各种文化类型积极影响的同时,努力降低或消除其消极影响。  相似文献   
99.
LGH-01型空气质量自动监测系统常见故障及维修   总被引:3,自引:2,他引:1  
介绍了 LGH-01型空气质量自动监测系统,对使用该系统时出现的常见故障和排除办法提供了解决思路,并且提出了使用该仪器时应严格按规程操作,要加强巡检工作和注意用电安全等日常维护的注意事项.  相似文献   
100.
Michael Pugh 《Disasters》2001,25(4):345-357
The relationship between military and civilian humanitarian organisations has developed in an increasingly integrative way. Military initiatives to institutionalise the relationship, since the interventions in Somalia and the Balkans, entail a dilution of humanitarian independence as was manifested in practice in Kosovo. Further, the state-centric foundations of military intervention run counter to the potential for humanitarian organisations to foster a cosmopolitan ethos that would not only preserve humanitarian principles but also contest statist assumptions about conflict, development and power.  相似文献   
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