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941.
Abstract.   Scientists in most countries are assessed by the number of papers published in journals that are cited in the Science Citation index. This article reviews the mine water related entries in the Science Citation Index Expanded and discusses the results. Mine water relevant literature is spread over more than 900 journals, with 13 of them accounting for 25% of all relevant papers. No journal focused on mine water relevant issues can be found in the Index.  相似文献   
942.
943.
The web services paradigm provides organizations with an environment to enhance B2B communications. The aim is to create modularized services supporting the business processes within their organization and also those external entities participating in these same business processes. Current web service frameworks do not include the functionality required for web service execution performance measurement from an organization perspective. As such, a shift to this paradigm is at the expense of the organizations performance knowledge, as this knowledge will become buried within the internal processing of the web service platform. This research introduces an approach to reclaim and improve this knowledge for the organization establishing a framework that enables the definition of web services from a performance measurement perspective, together with the logging and analysis of the enactment of web services. This framework utilizes web service concepts, DSS principles, and agent technologies, to enable feedback on the organizations performance measures through the analysis of the web services. A key benefit of this work is that the data is stored once but provides information both to the customer and the supplier of a web service, removing the need for development of internal web service performance monitoring.  相似文献   
944.
The literature contains numerous equations linking a soil's characteristics of compressibility to its index properties, such as liquid limit and plasticity index. As these equations are often used to obtain preliminary evaluations of the compression index Cc, it is important to know the reliability of these equations. The paper analyses some of the equations more frequently used to calculate Cc from laboratory index properties, using a methodology based on two specific indices: ranking distance and ranking index. Forty-six samples formed the data set, mainly of Blue Clays and Varicoloured Clays outcropping in the southern part of the Bradanic Foredeep. It was concluded that the most reliable equation correlates Cc with the shrinkage index.
  相似文献   
945.
A new method for rapid extraction of Volatile Organic Compounds (VOC) from low permeability, unconsolidated geologic media such as clayey soil has been developed and tested using trichloroethylene (TCE) as the model compound. The technique is based on a combination of sonication and mechanical agitation of the samples. The sample vials, mounted in a special holder attached to an orbital shaker, were immersed in an ultrasonic bath during extraction. The extracts were analyzed by gas chromatography with electron capture detection (GC-ECD). The method was validated using clay samples from a TCE-contaminated industrial site by comparing TCE recoveries to those obtained by the standard methanol extraction. In all cases, the recoveries obtained with the new method were the same or better than the recoveries obtained with the reference method. The extraction time was shortened from 5 days with the standard method to less than 2 h with the new method. The new technique makes it possible to analyze a large number of samples in a short time, without the need for sample preservation and prolonged storage. It has good potential for on-site analysis to facilitate decisions while field investigations are in progress.  相似文献   
946.
In this article, we describe the process of discovering similar patterns in time series and creating reference models for population groups in a medical domain, and particularly in the field of physiotherapy, using data mining techniques on a set of isokinetic data. The discovered knowledge was evaluated against the expertise of a physician specialized in isokinetic techniques, and applied in the I4 (Intelligent Interpretation of Isokinetic Information) project developed in conjunction with the Spanish National Center for Sports Research and Sciences for muscular diagnosis and rehabilitation, injury prevention, training evaluation and planning, etc., of elite athletes and ordinary people.  相似文献   
947.
This paper presents integer programming formulations and compares two approaches – weighting and lexicographic – to the multi‐objective, long‐term production scheduling in make‐to‐order manufacturing, where both maximization of customer service level and best utilization of production resources are integrated in the objective function. The problem objective is to assign customer orders for various product types and with various due dates to planning periods and to select machines for assignment in every period to complete all the orders with minimum numbers of tardy and early orders and with a leveled machine assignment over a planning horizon. The two approaches are applied to optimize long‐term production schedules in a flexible flowshop with parallel machines. Numerical examples modeled after a real‐world flexible assembly line in the electronics industry are provided and some computational results are reported.  相似文献   
948.
Design solutions have been proposed to implement generic data structures, however such techniques dedicated to algorithms are not well known. This article discusses various recurrent problems encountered when designing reusable, extensible algorithms for operations research. It explains how to use object‐oriented concepts and the notion of genericity to design algorithms that are independent of the data structures and the algorithms they use, but that can still interact deeply with them. An object‐oriented design is sometimes considered to be less efficient than a classical one, and operations research is one of these scientific fields where efficiency really matters. Hence, the main goal of this article is to explain how to design algorithms that are both generic and efficient. It also discusses specific recurring design issues for operations research software and proposes solutions that improve the genericity of the algorithms. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
949.
A near-field ultrasonic tomography method providing high resolution imaging for soft tissue in the reflection mode is reported. When the Born approximation is valid, the main limitation of this method is that it requires an incident pulse with infinite bandwidth, whereas the incident pulses used in practice have a limited bandwidth, which makes quantitative reconstruction impossible. The reconstructed image is qualitative in the sense that it is a band-pass filtered reconstruction of the impedance distribution. An optimization method based on the use of the geometrical information provided by the tomographic reconstruction is developed to obtain the quantitative information required. The object was approximated locally by an equivalent canonical body, on the basis of the previous global estimation. The inversion procedure is then carried out using the minimization of a cost function, which is the average over frequency of the difference between the measured field scattered by the object and the estimated field scattered by the equivalent canonical body. Assuming the object to be homogeneous by regions, the last step consists of assigning the estimated local impedance value to the region of interest. When the geometry of the real body is almost canonical, the optimization method yields accurate impedance assessments.  相似文献   
950.
A monolithic integration of filters on Si or GaAs substrates is highly desirable to miniaturize the outer dimensions of the cellular phones. But, direct monolithic integration of surface acoustic wave (SAW) filters is impossible with Si, which is nonpiezoelectric, and difficult with GaAs, which is weakly piezoelectric. One alternative is the deposition of a piezoelectric film on the semiconductor substrate. In this paper, we propose a modified coupling-of-modes (COM) approach, which can be used in the practical design of a layered ZnO/Si SAW filter. This is a dispersive SAW-layered filter, and some of the COM parameters become frequency dependent due to the phase velocity dispersion. The frequency response of the 3-step ladder type ZnO/Si SAW filter is analyzed and compared with the experimental results.  相似文献   
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