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针对市区中心繁华地段施工的特点,通过梅园中心地下车库工程实例详细介绍了逆作法施工工艺、技术要点及其实施效果,指出该方法具有安全、经济、工期短及绿色文明施工等特点,值得进一步推广。 相似文献
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R. E. Collins G. M. Turner A. C. Fischer-Cripps J. -Z. Tang T. M. Simko C. J. Dey D. A. Clugston Q. -C. Zhang J. D. Garrison 《Building and Environment》1995,30(4):459-492
The substantial progress in the science and technology of vacuum glazing that has occurred over the past few years is reviewed. Vacuum glazing up to 1 m × 1 m in size has been produced with an air-to-air, mid-device thermal conductance as low as 0.90 W m−2 K−1, compared with 1.3 W m−2 K−1 for high performance double glazing. The mechanical tensile stresses in vacuum glazing due to pressure and temperature differentials are well understood, and appear to be tolerably small. The internal vacuum is high, and extremely stable over long times at moderate temperatures. The likely cost of volume production of vacuum glazing should be only slightly greater than for high performance double glazing. 相似文献
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R Winsor 《International Journal of Project Management》1983,1(4):220-224
Owing to its numerical rather than visual presentation, numerical network analysis, a term used to encompass techniques such as the critical path method, has never really been accepted as a working tool in the building industry. To fill this gap, diagonal network analysis (DNA) was developed. The DNA chart displays in visual terms everything that numerical network analysis gives only in numerical terms, and shows overlapping of activities without having to construct complex ladders. An arrow programme need not be drawn first as the program does this for the user. The development of a program that could draw a DNA chart from input data simple enough for even a builder to understand is described. 相似文献
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Marcel Sala Francesc Soriguera Kevin Huillca Vernica Vilaplana 《Computer-Aided Civil and Infrastructure Engineering》2019,34(6):488-505
Empirical data is needed in order to extend our knowledge of traffic behavior. Video recordings are used to enrich typical data from loop detectors. In this context, data extraction from videos becomes a challenging task. Setting automatic video processing systems is costly, complex, and the accuracy achieved is usually not enough to improve traffic flow models. In contrast “visual” data extraction by watching the recordings requires extensive human intervention. A semiautomatic video processing methodology to count lane‐changing in freeways is proposed. The method allows counting lane changes faster than with the visual procedure without falling into the complexities and errors of full automation. The method is based on converting the video into a set of space–time still images, from where to visually count. This methodology has been tested at several freeway locations near Barcelona (Spain) with good results. A user‐friendly implementation of the method is available on http://bit.ly/2yUi08M . 相似文献
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Dye-sensitized-photo-oxidation—a new approach to the treatment of organic matter in sewage effluents
A new approach to the oxidation of organic matter in municipal wastewaters by photosensitization is described. Samples of aerated sewage effluents containing an added dye-sensitizer were exposed to u.v.-lamp or solar radiation. The photochemical oxidation of the sewage caused decreases in the content of the fecal coliform, of the chemical oxygen demand and of the methylene blue-active substances by 100, 67 and 90% of their initial values, respectively. The effluents obtained after the removal of the dye, by precipitation with bentonite clay, were colorless, non-odorous and with the amount of suspended solids considerably reduced. 相似文献
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L.O. Kolarik 《Water research》1983,17(2):141-147
Alkali treated magnetite (Fe3O4) is shown to be an excellent solid coagulant-adsorbent which is regenerable and reusable. It is effective for the removal of colour and turbidity from water. Alkali treated magnetite can be used alone or in conjunction with another primary inorganic coagulant or organic flocculant. Because of the accelerated kinetics of coagulation and particularly of sedimentation, this new technique is 3–6 times faster than the conventional coagulation-flocculation-sedimentation process. It also appears that filtration of the product water may not be necessary. Regeneration of the spent magnetite is achieved by contacting the used magnetite with 0.1 M sodium hydroxide. The development of the process on the laboratory scale using a jar test technique is discussed. 相似文献
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All agree that every organisation needs a strategy. Every organisation claims to have one. Yet few agree as to its appearance, meaning and intention. Most definitions have one thing in common: that strategy is at the very root of an organisation. strategy is a set of choices about ways of dealing with the political, economic, social and technological environment, and which serve to guide and co-ordinate all the plans and actions that the organisation needs. The author discusses the theory and practice of business strategy with particular reference to European Gas Turbines. Strategic approaches and layered strategies are discussed 相似文献
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以某医院新建综合住院大楼基坑支护设计为例,依据相关规范及该场区自然条件,采用了钢管内支撑基坑支护形式,结果表明该设计方案可提高整个体系刚度及有效控制基坑变形,取得了良好效果。 相似文献
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Morgan Sherwood 《The International journal of environmental studies》2013,70(1-4):211-217
After the Alaskan earthquake of 1964, the frontier fishing village of Seldovia was threatened by high tides along its picturesque downtown waterfront. The availability of federal reconstruction funds lured policy makers to opt for urban renewal rather than rehabilitation. The result was an economic, social and aesthetic disaster. The episode illustrates some of the difficulties of environmental management on the last U.S. frontier. 相似文献
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L. C. F. Ingerslev 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1998,13(4):357-363
Water in the shape of rivers, lakes, fjords, oceans and so on, sometimes seems to provide a barrier to improving the environment and preventing further development. Hitherto unconsidered options may be available to cross over or under a water barrier. Without full knowledge of the available possibilities, planners and decision-makers are not able to make the best-informed choices. This paper initially examines the relative attributes of bridges, ferries, submerged floating tunnels, immersed tunnels, soft ground tunnels and rock tunnels. Reasons for selection or rejection of each option are discussed. The paper goes on to introduce immersed and floating tunnels in more detail. Specific examples are given to convey the concepts. 相似文献
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George A. Atkinson 《Building Research & Information》1973,1(5):278-284
Building regulations vary internationally in their objectives and in the responsibilities they place upon designers and contractors, but they generally depend upon national or international codes and standards for their technical requirements. The systems operated in a number of European countries are discussed in this paper in terms of the internal environment of buildings and general considerations of public safety and health. The author refers to the influence of the relevant CIB Working Commissions in establishing internationally agreed standards for the internal environment of buildings and performance concepts. 相似文献
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《Water research》1986,20(2):215-220
Mathematical models of deep bed granular filters are usually based on two linked partial differential equations. The first is an equation of mass balance; the second expresses the kinetics of the process. The combination of the precise mass balance with the simple kinetic equation most commonly used leads to an inconsistency which has hitherto been resolved either by attempting to express the equations in “filter” rather than “absolute” time, or by assuming the offending terms are negligible. The inconsistency does not arise when a new, rational kinetic equation is combined with the more complicated, precise form of the mass balance equation. The new equations are, however, awkward to solve, and there remains an incentive to use simplified approximations which offer the possibility of exact solution. Comparison of series solutions for the simple and precise equations indicates that there is no loss of accuracy in using the approximations. It is also concluded that the concept of filter time does not simplify the mathematics. 相似文献
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spMorph: An exploratory space‐time analysis tool for describing processes of spatial redistribution
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This paper introduces an exploratory space‐time analysis tool for determining the two components of a spatial redistribution process: (i) the shock, which is the moment that triggers a spatial redistribution process; for example, a new policy, a war, an earthquake, etc.; and (ii) the duration of the regime fade, which is the time between the shock and the moment in which a new regime emerges as a better representation of the spatial distribution of the attribute. Two examples are provided: the first uses China's provincial per capita GDP between 1978 and 2008, and the second uses state level housing price and unemployment rate data for the US between 2002 and 2012. 相似文献
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A Bayesian space‐time approach to identifying and interpreting regional convergence clubs in Europe
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This study suggests a two‐step approach to identifying and interpreting regional convergence clubs in Europe. The first step calculates Bayesian probabilities for various assignments of regions to two clubs using a general stochastic space‐time dynamic panel relationship between growth rates and initial levels of income as well as endowments of physical, knowledge and human capital. The second step uses the club assignments in a dynamic space‐time panel data model to assess long‐run dynamic direct and spillover responses of regional income levels to changes in initial period endowments for clubs that were identified. We find different dynamic partial derivative responses to endowments by regions in the two clubs that appear consistent with low‐ and high‐income regions as clubs. 相似文献
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H. H. Einstein 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2000,15(1):13
Numerous tunnels have been built and new tunnels are planned in the Swiss Jura Mountains, and most of them intersect Opalinus Clayshale. This paper reviews several tunnel case histories which show that Opalinus Clayshale can be quite problematic by swelling during construction and also during operation, if the invert cover is not strong enough and if water can penetrate into the shale. Modern testing methods and a newly developed behavioral model based on these tests are then presented. They clearly show that Opalinus Clayshale when unloaded as can occur around the tunnel perimeter swells which in turn can induce creep and even failure. Considering this behavior in design and construction will reduce swelling and creep. Modern, TBM-based tunnel construction which utilizes prefabricated liner elements satisfies these requirements. In addition, the paper describes project management procedures that allow one to include the risks associated with swelling when assessing and awarding bids. 相似文献