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451.
Anastasios I. Stamou Kimon Hadjibiros Andreas Andreadakis Alexandra Katsiri 《Environmental Modeling and Assessment》2007,12(3):157-170
A water quality model (MERES) is applied in the multi-purpose reservoir of Plastiras in Greece. The model was calibrated with
limited field data using the standard trial and error procedure; next, it was applied for four scenarios of reservoir operation,
which correspond to four values of minimum water levels (MWL). Model results were combined with landscape aesthetics to establish
a “safe” MWL in the reservoir. MWL was proposed to be +784 m, a value that ensures a very good water quality by retaining
the reservoir in the status of “a little beyond oligotrophic” and a very good quality of landscape with an acceptable area
of dead zones; it also ensures an annual release of 127.5 hm3 of water within a reliability level of 90%. This quantity can be considered as acceptable from the water supply point of
view. 相似文献
452.
This paper presents a case study of the Abanico Medicinal Plant and Organic Agriculture Microenterprise Project in the Arenal Conservation Area, Costa Rica. Microenterprise is the Sustainable Development and the Women in Development model for gender equity and environment of the World Bank, International Monetary Fund and large non-government organizations, like the World Wildlife Fund-Canada. The authors of this paper argue that debt-for-nature investment in microenterprise and ecological economic models are not distinct from neoclassical economic and development models that created the environmental, social and cultural crises in the first place. This case study shows that the world market accommodates only one model of development: unsustainable export-oriented production based on flexible labour markets, low wages, indebtedness and low cost production. Working standards in those micro-enterprises are eroded due to many factors,including indebtedness. What happened at a national level in non-industrial countries with the international debt crisis is now mirrored in individual indebtedness through microenterprise. Is current development policy creating a new form of indentured servitude? Medicinal plants, prior to commodification, were a source of women's power and upon commodification in international development projects, are the source of their exploitation. 相似文献
453.
目前,中国农村污水治理面临体制机制障碍和政府组织实施等诸多难题.县域是具备财政统筹和政策制定能力的最基本行政区划,以县域为基本单元组织实施农村污水治理具有必要性和可行性.为此,需要厘清县级政府及其职能部门组织实施责任,注重农村污水处理工程设计管理、工程施工管理、工程资金管理以及农村污水处理工程的长效运行管理.这种“过程管理”,能够解决农村污水治理的组织实施难题,改善农村地区水环境和卫生状况,促进农村经济和社会可持续发展. 相似文献
454.
基于对江苏省太湖流域农村生活污水处理设施的全面调研,统计分析了江苏省太湖流域农村生活污水处理设施现状,包括建设数量、建设规模、处理工艺、运维模式、经费来源等,探讨了江苏省太湖流域农村生活污水处理设施存在的问题并提出建议。结果表明:目前江苏省太湖流域农村生活污水处理设施以中小规模(<100 t/d)为主,主要采用生物生态耦合处理技术,出水一般执行(GB 18918-2002)《城镇污水处理厂污染物排放标准》中的一级B标准,以属地管理的运维模式为主。应加快制订符合江苏省太湖流域的农村生活污水处理设施建设标准,并形成责任主体明确、监管制度完善、资金投入有保障的长效稳定运行体制。 相似文献
455.
安全生产工作体制思考 总被引:1,自引:0,他引:1
李忠祥 《中国安全生产科学技术》2011,7(10):84-88
一个切合实际特点、设置科学合理、责权界定清晰、运行顺畅有效的安全生产工作体制是发挥各方作用、共同做好安全工作的基础和前提。从安全生产工作体制的基本内涵出发,回顾了我国不同时期国情特点下的安全生产工作体制。针对当前国情特点和安全生产工作体制状况进行了分析,指出监督(察)与管理是一对矛盾,两种职能由同一部门行使不合理,应当分开,国家监察职责不宜分散而应集中,以减少执法成本和企业负担,并且要加强中介机构、非政府组织(NGO)和第四权力―媒体的作用的观点,提出了当前安全生产工作体制的新思考。 相似文献
456.
本文简要介绍了可靠性强化试验技术原理与特点,总结了可靠性强化试验技术在家电产品研发阶段中的应用方法,详细阐述了可靠性强化试验过程和试验剖面特点;给出了部分产品实施可靠性强化试验的结果与实施经验,论述了如何在家电产品中经济高效地实施可靠性强化试验技术. 相似文献
457.
458.
Benedito Braga Paulo S. F. Barbosa 《Journal of the American Water Resources Association》2001,37(4):837-852
ABSTRACT: A network flow algorithm has been developed for the optimization of real‐time operation of a multiple reservoir system. Two purposes have been considered in the operation: flood control and hydropower generation. A special network structure was developed which allows the consideration of river routing. A multiobjective formulation is utilized thus allowing generation of a non‐dominated curve. The effect of imperfect forecast on the performance of the real‐time operation model is also evaluated. An application is made to a subsystem of the Brazilian hydroelectric system, located in the Paranapanema river basin. In this case study, the model showed good performance under the largest flood of the historical records. 相似文献
459.
压力容器根据各自的特点和在生产工艺流程中的作用 ,都有其特定的操作程序和操作方法。尽管各种压力容器的使用工况不尽一致 ,却有共同的安全操作要点。从操作的角度 ,说明如何预防安全事故。 相似文献
460.
Characteristics of PM10, PM2.5, CO2 and CO monitored in interiors and platforms of subway train in Seoul, Korea 总被引:1,自引:0,他引:1
This study was performed to investigate the concentration of PM10 and PM2.5 inside trains and platforms on subway lines 1, 2, 4 and 5 in Seoul, KOREA. PM10, PM2.5, carbon dioxide (CO2) and carbon monoxide (CO) were monitored using real-time monitoring instruments in the afternoons (between 13:00 and 16:00). The concentrations of PM10 and PM2.5 inside trains were significantly higher than those measured on platforms and in ambient air reported by the Korea Ministry of Environment (Korea MOE). This study found that PM10 levels inside subway lines 1, 2 and 4 exceeded the Korea indoor air quality (Korea IAQ) standard of 150 μg/m3. The average percentage that exceeded the PM10 standard was 83.3% on line 1, 37.9% on line 2 and 63.1% on line 4, respectively. PM2.5 concentration ranged from 77.7 μg/m3 to 158.2 μg/m3, which were found to be much higher than the ambient air PM2.5 standard promulgated by United States Environmental Protection Agency (US-EPA) (24 h arithmetic mean: 65 μg/m3). The reason for interior PM10 and PM2.5 being higher than those on platforms is due to subway trains in Korea not having mechanical ventilation systems to supply fresh air inside the train. This assumption was supported by the CO2 concentration results monitored in tube of subway that ranged from 1153 ppm to 3377 ppm. The percentage of PM2.5 in PM10 was 86.2% on platforms, 81.7% inside trains, 80.2% underground and 90.2% at ground track. These results indicated that fine particles (PM2.5) accounted for most of PM10 and polluted subway air. GLM statistical analysis indicated that two factors related to monitoring locations (underground and ground or inside trains and on platforms) significantly influence PM10 (p < 0.001, R2 = 0.230) and PM2.5 concentrations (p < 0.001, R2 = 0.172). Correlation analysis indicated that PM10, PM2.5, CO2 and CO were significantly correlated at p < 0.01 although correlation coefficients were different. The highest coefficient was 0.884 for the relationship between PM10 and PM2.5. 相似文献