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41.
Estrogenic personal care products in a greywater reuse system. 总被引:1,自引:0,他引:1
H R Andersen M Lundsbye H V Wedel E Eriksson A Ledin 《Water science and technology》2007,56(12):45-49
The occurrence and fate of parabens in a greywater system was assessed. The potential for removal of residual paraben concentrations in effluent greywater with chlorine dioxide was also investigated. The influent to the greywater plant was characterised by considerable variation, with concentrations from below the detection limit to 40 microg/L and the five commonly used parabens in consumer products were frequently detected. After the biological treatment only two paraben were detected with concentration from 65-120 ng/L. Chlorine dioxide treatment of the biologically treated effluent with dosages down to 0.75 mg/L resulted in more than 97% reduction of all parabens. Formation of the by-product chloroform was insignificant from the chlorine dioxide treatment. 相似文献
42.
Stephen V. Marks 《Bulletin of Indonesian Economic Studies》2004,40(2):227-242
A major challenge for Indonesian economic policy makers is to avoid the recurrence of conditions that could trigger a new economic crisis. One of the important dimensions of this challenge will be to conduct fiscal policy in a way that is sustainable, given the level of interest rates and the rate of growth of the economy. This paper synthesises various approaches to the measurement of fiscal sustainability that have appeared in the economic literature, relates these measures to the fundamental concept of fiscal solvency, and applies the framework to Indonesia over the period 1991–2003. The domestic and foreign debt positions of the central government are treated separately, to capture the influence of exchange rate changes on the relative costs of domestic and foreign borrowing. The empirical analysis indicates that Indonesia has met the fiscal sustainability criterion in recent years, except when the rupiah has depreciated heavily. 相似文献
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V. A. Melent'ev I. M. Mityushina 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1985,19(5):241-246
Conclusion On the basis of the foregoing conditions about the design of hydraulic-fill dams and technology of their construction and also with consideration of the results of comparative calculations of the permeability of these dams, for the upper reservoirs of pumped-storage stations we can recommend dams which have reliable impervious elements, namely, a diaphragm, facing, or placed clay core.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 31–35, May, 1985. 相似文献
45.
Optimal Operation of Reservoir Systems using Simulated Annealing 总被引:5,自引:0,他引:5
A stochastic search technique, simulated annealing (SA), is used to optimize the operation of multiple reservoirs. Seminal application of annealing technique in general to multi-period, multiple-reservoir systems, along with problem representation and selection of different parameter values used in the annealing algorithm for specific cases is discussed. The search technique is improved with the help of heuristic rules, problem-specific information and concepts from the field of evolutionary algorithms. The technique is tested for application to a benchmark problem of four-reservoir system previously solved using a linear programming formulation and its ability to replicate the global optimum solution is examined. The technique is also applied to a system of four hydropower generating reservoirs in Manitoba, Canada, to derive optimal operating rules. A limited version of this problem is solved using a mixed integer nonlinear programming and results are compared with those obtained using SA. A better objective function value is obtained using simulated annealing than the value from a mixed integer non-linear programming model developed for the same problem. Results obtained from these applications suggest that simulated annealing can be used for obtaining near-optimal solutions for multi-period reservoir operation problems that are computationally intractable. 相似文献
46.
V. G. Radchenko V. M. Semenkov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(10):685-691
Geosynthetic materials in the form of geomembranes, geotextiles, geonets, geomats, geocomposites, etc., are used widely in modern dam construction. The article describes structural elements of dams in which various types of geosynthetics are used and those functions which geosynthetics perform in these elements.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 50–54, October, 1992. 相似文献
47.
Strategic partnerships are commonplace in today's global economy. Effective use of partnerships are viewed increasingly as an important issue facing small, growth-oriented firms. A key debate is how small firms should manage supplier partnerships. Contrasting the debate about the extent to which small firms are inertial versus adaptive, the impact of growth on value chain partnerships with suppliers was investigated. Data collected from 91 pharmaceutical-related firms is used to test the proposition that firm growth is related positively to maintaining or to expanding relationships with suppliers, not to terminating partnerships. The paper further posits that this relationship between firm growth and the amount purchased from a supplier is moderated by the perceived effectiveness of the value-chain partnerships such that when effectiveness is higher, the relationship between sales growth and the amount purchased from a value-chain partner is stronger. The propositions, which are tested with regression analysis, are supported partially. 相似文献
48.
Samuel V. Bruton 《Journal of Business Ethics》2004,49(2):179-187
The Golden Rule is endorsed in oneform or another by most cultures and majorreligions and is still espoused byphilosophers, business ethicists, and popularbusiness authors. Because it also resonateswith undergraduate business majors, it can bean effective teaching tool. This paperdescribes a way of teaching the Golden Rulethrough a series of business-oriented examplesintended to bring out its strengths andweaknesses. The method described alsointroduces students to some basic moralreasoning skills and acquaints them with a widerange of moral issues that arise in business. Kant's Formula of Humanity is discussed in thefinal section as a principle that overcomes atleast some of the Golden Rule's defects. 相似文献
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