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61.
62.
Drainage blankets (DB) are used for leachate recirculation in bioreactor landfills and consist of highly permeable material placed over a large area of the landfill with the leachate injection pipe embedded in the material at specified locations. DBs are generally installed at different depth levels during the waste filling operations. Very limited information is reported on performance of DBs, and that which exists is based on a small number of field monitoring and modeling studies. A rational method for the design of landfills using DBs has not been developed. This study performs a parametric analysis based on a validated two-phase flow model and presents design charts to guide the design of DBs for given hydraulic properties of MSW, the leachate injection rate and the dimensions and locations of the DB as measured from the leachate collection and recirculation system (LCRS) located at the bottom of the landfill cell. Numerical simulations were performed for the two established MSW conditions: homogeneous–isotropic and heterogeneous–anisotropic waste. The optimal levels of leachate saturation, wetted width, wetted area and developed pore water and pore gas pressures were determined, and design charts using the normalized parameters were developed. An example is presented on the use of design charts for typical field application. 相似文献
63.
杨晓志 《矿物岩石地球化学通报》2015,(3)
在过去的二十多年间,高温高压实验地球科学研究得到了蓬勃发展,凭借其高度的灵活性和易于与其他分支学科相结合的优点,在很多不同的研究领域中都取得了令人瞩目的成果,并已发展成为国际地球科学的前沿领域和重要方向之一,同时也是固体地球科学最强有力研究手段之一。相比之下,国内的高温高压实验地球科学研究还显得相对比较薄弱,相关系统性的认识还有待增强。本文对高温高压实验研究的发展历程、方法原理、仪器设备以及在地球科学研究中的一些应用进行简单的介绍,旨在让更多的国内学者对这一领域有更深入的了解。 相似文献
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恒星光干涉议定天镜的转动是用五相步进电机来驱动的,它需要的控制信号由软件实现。软件设计是控制系统中最困难的部分,尽可能地用软件实现硬件功能,不仅可以降低成本,更重要的是,便于更新及升级。在观测过程全自动化的前提下,着重提出了我国恒星光干涉议实验系统中定天镜子系统的软件设计方案。 相似文献
66.
《The Professional geographer》1988,40(1):116-131
Books reviewed in this article: Boundary Control and Legal Priniciples . Curtis M. Brown , Walter G. Robillard and Donald A. Wilson . Lost Initiatives: Canada's Forest Industries, Forest Policy, and Forest Conservation . R. Peter Gillis and Thomas R. Roach . The Navajo Atlas: Resources, People, and History of the Dine Bikeyah . James M. Goodman . The City and the Sign . M. Gottdiener AND Alexandros Ph . Lagopoulos , EDS. The Comfortable House: North American Suburban Architecture 1890–1930 . Alan Gowans . Arabic-Islamic Cities. Building and Planning Principles . Besim Salim Hakim . Contemporary Climatology . Ann Henderson -Sellers and Peter J. Robinson . A Trace of Desert Waters . Samuel G. Houghton . Geography, Resources and Environment. Vol. 1: Selected Writings of Gilbert F. White. Vol. 2: Themes from the Work of Gilbert F. White . Robert W. Kates AND Ian Burton , ED. Spatial Dimensions of Unemployment and Underemployment (A Case Study of Rural Punjab) . Gopal Krishan . Maps of the Holy Land: Cartobibliography of Printed Maps, 1475–1900 . Compiled by Eran Laor , assisted by Shoshana Klein . The Geography of Third World Cities . Stella Lowder . A Perspective on U.S. Farm Problems and Agricultural Policy . Lance Mc Kinzie , Timothy G. Baker AND Wallace E. Tyner . Soil Erosion and Its Control. R.P.C . Morgan , ED Geopolitics . Patrick O'Sullivan . Landscape, Meanings and Values . Edmund C. Penning -Rowsell AND David Lowenthal , EDS. 相似文献
67.
文化独特性是文化遗产型景区的核心吸引力,了解和欣赏异质文化遗产是文化旅游者的主要动机,解说翻译是跨文化遗产旅游的桥梁。由于国内旅游规划对文化遗产旅游解说特点研究不够,景区管理者对双语解说信息创作对象不了解,导致文化遗产解说与翻译的质量影响了跨文化遗产旅游的解说教育效果,错过了通过文化遗产旅游平台对外宣传中华文化的良好机会。综述了旅游解说的概念、内涵以及有效解说和信息创作的原则,在总结文化遗产旅游特点的基础上,提出了文化遗产型景区英文解说翻译应针对国际旅游者特点的信息再创造的观点。建议文化遗产旅游景区制定针对国际旅游者消费特点的双语解说规划;旅游规划和翻译学术界应重视旅游双语解说规划和翻译的研究;翻译者在具备双语、双文化翻译能力的同时,还应该了解旅游解说和信息创作的跨学科知识。 相似文献
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69.
M. A. Hariri-Ardebili P. Boodagh 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2019,13(1):34-52
This paper presents a methodology to evaluate the seismic reliability of geostructures in an optimal way. Taguchi design of experiments are adopted to find the most efficient and cost-effective combination of material properties in the uncertainty domain. Twelve uniform and mixed design models are tested. A polynomial-based response surface meta-model is built for each one and the accuracy of perdition is examined using 10,000 Monte Carlo simulations. A two-dimensional gravity dam is used as a vehicle for probabilistic transient analyses. The ground motion record-to-record variability is added as well using over one hundred earthquake records selected based on probabilistic seismic hazard analysis. Dynamic sensitivity of epistemic random variables are evaluated for the first time. Finally, an efficient and practical procedure is proposed in order to determine the reliability index of the geostructures. This approach, in fact, can be generalised for any type of engineering structures dealing with multi-hazard problems. 相似文献