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991.
由于大坝出现了严重渗漏和管涌,1999年永记水库被鉴定为病险水库。同年开始了除险加固工程,对永记水库的防渗问题采用沟槽混凝土防渗墙处理,经过补强加固后,从实际运行和实测资料来看,坝体防渗效果良好。  相似文献   
992.
河北省水土保持生态修复试点工作存在的主要问题及对策   总被引:3,自引:1,他引:2  
河北省近两年来实施的生态修复试点工作表明。水土保持生态修复不仅是恢复和改善生态环境的重要措施,也是改善当地群众生产生活条件、调整农业生产结构、增加农民收入的重要手段,是促进农村生态经济可持续发展、加速治理水土流失的重要途径;近两年来,该省在生态修复工程建设中取得了一定的成绩,但也存在一些问题。现重点介绍了河北省生态修复工作的主要成效,指出了存在的问题,提出了相关的对策。  相似文献   
993.
Extensive desnagging (removal of large woody debris and living riparian vegetation) and associated river improvement works were conducted in rivers of southeastern Australia (Victoria and New South Wales) between at least 1886 and 1995. Swamp drainage, large woody debris removal and vegetation clearing were strongly supported by legislation, government funding and institutional arrangements in both states. As a result, large amounts of large woody debris were removed from rivers, regenerating indigenous vegetation was cleared from within designed alignment widths and, ironically, huge numbers of exotic trees, especially willows, were planted. The environmental impacts of desnagging have only been documented on a few impacted rivers but have included increased flow velocity, spatially extensive bed degradation, massive channel enlargement and loss of fish habitat. Recognition of the need for more integrated land and water management, and new research on the hydraulic, geomorphic, biogeographic and ecological significance of large woody debris and the values of indigenous riparian vegetation during the 1980s led to a major shift in river rehabilitation. We have drawn on our own and other published research to further develop a set of guidelines for the incorporation of large woody debris into river rehabilitation plans. Our guidelines extend those recently prepared for southeastern Australia and address site selection, where to place timber, the amount to be introduced, how to distribute it, techniques of introduction and woody debris sources. However, in the long term, riparian vegetation rehabilitation within the potential recruitment zone is essential to supply large woody debris. Given that our results demonstrate that very large woody debris makes a significant contribution to the total loading, it will be a very long time (>100 years) before natural recruitment can be recreated. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
994.
Consumer-run programs and clubhouses are 2 important models in the emerging field of psychosocial rehabilitation according to the 1999 Surgeon General's report (U.S. Department of Health and Human Services, 1999). However, no published studies have compared the operations and services of these 2 models. The research reported here involves a statewide study of a matched sample of 29 clubhouses and 29 consumer-run drop-in centers (CDIs), with data gathered by obtaining documents from and conducting on-site interviews with agency directors. As expected, the authors found greater member control and involvement at CDIs and more instrumental services and activities at clubhouses. The authors also found that clubhouses had substantially more resources than CDIs and that CDIs showed significantly greater variance across programs on most measures. Implications for planning and further research are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
城镇埋地管道非开挖内衬PE管修复技术   总被引:1,自引:0,他引:1  
城镇供水、排污、燃气管道因结垢、腐蚀等问题不能满足正常运行要求,必须进行维修。非开挖内衬PE管修复技术可满足城镇埋地管道修复的要求,该技术具有不破坏硬化路面和建筑物、施工速度快、利于环保、适用范围广、经济效益好、可提高输送能力、修复后的管道使用寿命长等优点。文章介绍了内衬PE管修复技术的施工程序,强调了PE管道热熔焊接质量控制要求。  相似文献   
996.
消防队员在紧急救火行动或灭火演练中如果得不到很好的休息和补水,就会有生病和受伤的危险,还有可能威胁到现场其他成员的安全。人员复原将大大减少针对消防队员的事故和伤害,是有效防止诸如高温慌乱、热浪袭击、构筑物倒塌等严重情形发生的一个至关重要的因素。  相似文献   
997.
998.
Objective: In order to address the potential compounded risk in the population of aging traumatic brain injury (TBI) survivors who continue to drive, the authors synthesized literatures regarding the impact of aging or TBI on driving. Study Design: PubMed searches were conducted utilizing combinations of the following terms: driving, aging, elderly, TBI, cognition, seizures, vision, hearing, rehabilitation, sleep, fatigue, and assessment. Additional sources were also identified from the bibliographies of articles obtained and the Transportation Research Information Service electronic database. Clinically relevant human studies written in English were reviewed. Results: Using a conceptual framework developed by W. H. Brouwer and F. K. Withaar (1997), the authors of the current review highlight driving-related obstacles for TBI survivors and aging adults and suggest that individuals aging with TBI may be at increased risk for driving-related problems. Implications: Areas for clinical consideration include seizures, sleepiness and fatigue, vision, cognition, driving assessment, and caregiver involvement. The need for further study of postacute driving assessment and rehabilitation is highlighted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
1000.
Reviews the book, Spinal cord injuries: Psychological, social, and vocational rehabilitation, 2nd Edition by Roberta B. Trieschmann (1988). Despite the extensive rewriting and reorganization, however, the clarity and readability of the first edition has not been sacrificed. Owners of the first edition may want to obtain this one as well. In addition to presenting the information on psycho/social/vocational dimensions of spinal cord injury (SCI) in a developmental manner, from acute onset through rehabilitation and long-term adjustment issues, the author also discusses in depth such issues as traumatic brain injury, locus of control, substance abuse, independent living, and so on. Some of the topics covered in this edition that are not dealt with in the first edition are athletics, biofeedback, community integration, gender issues, quality of life, parenting, and respirator dependency. Some topics such as aging, attitudes, family issues, and sexuality are dealt with more completely. In addition to the empirical, critical analysis of the research on SCI that the first edition was known for, the second edition also suggests ways in which the research needs to be improved and supplemented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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