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The influence of mesquite gum on the interfacial tension between liquid paraffin and distilled water has been studied as a function of gum concentration, pH, and added NaCl or CaCl2. The time dependence of the reduction in interfacial tension was influenced by all three variables. Diffusion to the oil-water interface was the dominant factor in the initial decrease of interfacial tension when low mesquite gum concentrations were used. Reconformation of molecules adsorbed at the oil-water interface controlled the reduction in interfacial tension at longer times when using more concentrated gum solutions. 相似文献
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B. F. Sherman 《Journal of Geometry》1992,43(1-2):178-187
A result on enclosed (k,n)-arcs in PG(2,q) is used to characterise all minimal blocking sets of sizes =q +n in PG(2,q) with at least twon-secants. This also permits a slight extension of the bounds on blocking sets established by Blokhuis and Brouwer. 相似文献
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Benchmarking is a widely cited method to identify and adopt best-practices as a means to improve performance. Data envelopment
analysis (DEA) has been demonstrated to be a powerful benchmarking methodology for situations where multiple inputs and outputs
need to be assessed to identify best-practices and improve productivity in organizations. Most DEA benchmarking studies have
excluded quality, even in service-sector applications such as health care where quality is a key element of performance. This
limits the practical value of DEA in organizations where maintaining and improving service quality is critical to achieving
performance objectives. In this paper, alternative methods incorporating quality in DEA benchmarking are demonstrated and
evaluated. It is shown that simply treating the quality measures as DEA outputs does not help in discriminating the performance.
Thus, the current study presents a new, more sensitive, quality-adjusted DEA (Q-DEA), which effectively deals with quality
measures in benchmarking. We report the results of applying Q-DEA to a U.S. bank's 200-branch network that required a method
for benchmarking to help manage operating costs and service quality. Q-DEA findings helped the bank achieve cost savings and
improved operations while preserving service quality, a dimension critical to its mission. New insights about ways to improve
branch operations based on the best-practice (high-quality low-cost) benchmarks identified with Q-DEA are also described in
the paper. This demonstrates the practical need and potential benefits of Q-DEA and its efficacy in one application, and also
suggests the need for further research on measuring and incorporating quality into DEA benchmarking.
The review process of this paper was handled by the Edit-in-Chief Peter Hammer. 相似文献
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