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Many Practical Applications (many + practical_application)
Selected AbstractsDrawdown and Stream Depletion Produced by Pumping in the Vicinity of a Partially Penetrating StreamGROUND WATER, Issue 5 2001James J. Butler Jr. Commonly used analytical approaches for estimation of pumping-induced drawdown and stream depletion are based on a series of idealistic assumptions about the stream-aquifer system. A new solution has been developed for estimation of drawdown and stream depletion under conditions that are more representative of those in natural systems (finite width stream of shallow penetration adjoining an aquifer of limited lateral extent). This solution shows that the conventional assumption of a fully penetrating stream will lead to a significant overestimation of stream depletion (> 100%) in many practical applications. The degree of overestimation will depend on the value of the stream leakance parameter and the distance from the pumping well to the stream. Although leakance will increase with stream width, a very wide stream will not necessarily be well represented by a model of a fully penetrating stream. The impact of lateral boundaries depends upon the distance from the pumping well to the stream and the stream leakance parameter. In most cases, aquifer width must be on the order of hundreds of stream widths before the assumption of a laterally infinite aquifer is appropriate for stream-depletion calculations. An important assumption underlying this solution is that stream-channel penetration is negligible relative to aquifer thickness. However, an approximate extension to the case of nonnegligible penetration provides reasonable results for the range of relative penetrations found in most natural systems (up to 85%). Since this solution allows consideration of a much wider range of conditions than existing analytical approaches, it could prove to be a valuable new tool for water management design and water rights adjudication purposes. [source] Comment on ,C.-P.HYDROLOGICAL PROCESSES, Issue 6 2008N.-M. Abstract There are both practical and theoretical issues to consider when doing recession analyses of the type introduced by Brutsaert and Nieber (1977). Tung et al. (2004) point out a practical issue, which is the error introduced by using time-averaged values of discharge. The issue, however, is probably not serious for many practical applications and the error can be made negligible by using time intervals that are appropriate to the time rate of change in discharge. Copyright © 2007 John Wiley & Sons, Ltd. [source] Experimental study of a turbulent cross-flow near a two-dimensional rough wall with narrow aperturesAICHE JOURNAL, Issue 10 2008Satya Mokamati Abstract Turbulent flow over a rough wall with suction or blowing is a common fluid mechanics problem that has many practical applications including pulp screening. To better understand, the complex hydrodynamics at the critical region near the surface of the wall, the streamwise mean and velocity fluctuations were determined experimentally using laser Doppler velocietry. The near-wall streamwise velocity fluctuations and local mean streamwise velocity were shown to be a strong function of the surface roughness, and the aperture and cross-flow velocities. A correlation for the mean velocity and the wall shear stress acting near the wall was determined. © 2008 American Institute of Chemical Engineers AIChE J, 2008 [source] Investigation into microstrip dual-mode bandpass filters (BPFS) with in-line feed-line configurationsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2006JiaLin Li Abstract Based on the geometry relationship of the conventional dual-mode ring resonators, this study concisely describes the operation principle of a kind of dual-mode resonator filters with in-line feed-lines. The investigated filter topology is fed by two pairs of orthogonal branch lines and can realize in-line configuration for the input and output (I/O) ports, which is useful in many practical applications. Meanwhile, the influences of feed-lines on transmission-zeros (TZs) are, for the first time, investigated to guide the design of this kind of filters. Several demonstrators are designed and examined, and good results are obtained. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2008,2013, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21845 [source] Fast permutation routing in a class of interconnection networksNETWORKS: AN INTERNATIONAL JOURNAL, Issue 2 2002Ehab S. Elmallah Abstract This paper considers the following permutation routing problem: Given an N × N augmented data manipulator (ADM) network and a permutation , between its N inputs and outputs, can all the traffic connections of , be routed through the network in one pass? A number of backtrack search algorithms have been devised for recognizing ADM admissible permutations. None of the published results, however, appears to settle the time complexity of the problem. The goal of this paper was to answer the question positively by showing the first polynomial time bound for solving the problem. The devised algorithm requires O(N1.695) time to decide whether a given permutation , is admissible and compute a setting of the switches whenever , is admissible. For many practical applications, the obtained bound compares favorably with the O(N lg N) size of an N -input ADM network. © 2002 Wiley Periodicals, Inc. [source] Flat bulk-solvent model: obtaining optimal parametersACTA CRYSTALLOGRAPHICA SECTION D, Issue 9 2002Andrei Fokine A bulk-solvent correction is regularly used for macromolecular refinement. The flat model of the bulk solvent is considered to be the most reliable. It is shown that the standard procedure does not always result in the optimal values of the bulk-solvent correction parameters. A method to obtain the best values for parameters ksol and Bsol of the flat-solvent model is discussed. The values of correctly determined parameters for crystallographic structures deposited in the Protein Data Bank are clustered around ksol = 0.35,e,Å,3 and Bsol = 46,Å2, which have a reasonable physical meaning. Such a distribution allows the use of these mean values of solvent parameters for many practical applications when refined parameters cannot be obtained, especially when an atomic model in the unit cell is not yet known. [source] | |||||||||||||