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51.
This article develops principles for an evaluation of the efficiency of a savings bank. It starts out from the observation that such a bank is less profit oriented than a commercial bank. The customer is a vital stakeholder to the savings bank implying a greater emphasis on customer service provision. We are using data envelopment analysis (DEA) as a method to consider the service orientation of savings banks. We thereby demonstrate how an evaluation of the performance of savings banks according to “service efficiency” differs from an evaluation based on the traditional “profit” or shareholder concept. We determine the number of Swedish savings banks being “service efficient” as well as the average degree of service efficiency in this industry. 相似文献
52.
S. Minkevičius 《Acta Appl Math》2008,104(3):271-285
The model of an open queueing network in heavy traffic has been developed. These models are mathematical models of computer
networks in heavy traffic. A limit theorem has been presented for the virtual waiting time of a customer in heavy traffic
in open queueing networks. Finally, we present an application of the theorem—a reliability model from computer network practice. 相似文献
53.
利用最小调整法求解特殊的二维0-1规划 总被引:1,自引:0,他引:1
具有特殊约束的二维0-1规划的实际应用广泛,在解法中多是应用传统算法,或是在它基础上进行改进,但是此类解法计算繁琐不易推广.针对这种情形,本文引入最小调整法处理此类问题,并将其与传统算法进行对比,充分展示了该方法的优越性,呈现出灵活、方便、简单、易行的特点.通过举例验证了方法的有效性. 相似文献
54.
Peixia Gao Sabine Wittevrongel Joris Walraevens Herwig Bruneel 《Mathematical Methods of Operations Research》2008,67(2):269-284
In this paper, we study the behavior of a discrete-time multiserver buffer system with infinite buffer size. Packets arrive
at the system according to a two-state Markovian arrival process. The service times of the packets are assumed to be constant,
equal to multiple slots. The behavior of the system is analyzed by means of an analytical technique based on probability generating
functions (PGF’s). Explicit expressions are obtained for the PGF’s of the system contents and the packet delay. From these,
the mean values, the variances and the tail distributions of the system contents and the packet delay are calculated. Numerical
examples are given to show the influence of various model parameters on the system behavior. 相似文献
55.
Most macroeconomic time series are reported on a quarterly basis. However, in many cases, official statistical agencies report annual (or ‘year-on-year’) growth rates rather than the quarterly data themselves. In this paper, we demonstrate how to recover seasonally adjusted quarterly growth rates from annual growth rates that are reported quarterly. As an illustration, we apply the technique to the highly seasonal UK Retail Sales series. Using only the annual growth rates calculated from the underlying data, we find that our procedure generates estimated seasonally adjusted quarterly growth rates that are almost indistinguishable from the ‘true’ seasonally adjusted quarterly growth rates. 相似文献
56.
The AME 2020 atomic mass evaluation (I). Evaluation of input data,and adjustment procedures
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This is the first of two articles(Part I and Part II)that presents the results of the new atomic mass evaluation,Ame2020.It includes complete information on the experimental input data that were used to derive the tables of recommended values which are given in Part II.This article describes the evaluation philosophy and procedures that were implemented in the selection of specific nuclear reaction,decay and mass-spectrometric data which were used in a least-squares fit adjustment in order to determine the recommended mass values and their uncertainties.All input data,including both the accepted and rejected ones,are tabulated and compared with the adjusted values obtained from the least-squares fit analysis.Differences with the previous Ame2016 evaluation are discussed and specific examples are presented for several nuclides that may be of interest to Ame users. 相似文献
57.
58.
磁场电源是 HL-2M 装置初始等离子体放电的重要组成部分,它关系到 HL-2M 装置零场的建立,等
离子体的击穿和维持及位形控制。为实现初始等离子体放电所需的供电电压和电流,对磁场电源从主回路、控制、
测量和保护分别作了相应的调整。在此基础上进行了大量的工程调试,确保了磁场电源的控制和保护等性能达到
初始等离子体放电的需求。在磁场电源运行中,电源控制性能和输出参数的一致性、纹波质量等都有显著提高。
介绍了磁场电源在调试及 HL-2M 装置初始放电中的应用。 相似文献
59.
Modification of membrane surface for anti-biofouling performance: Effect of anti-adhesion and anti-bacteria approaches 总被引:2,自引:0,他引:2
Membrane biofouling refers to the undesirable accumulation (attachment and growth) of microorganisms on a membrane surface, and has been a major problem in the application of membrane technology in water and wastewater treatment. In this study, the surface of a base membrane made of chitosan/cellulose acetate blend was modified by reacting with heparin, quaternary ammonium or being immobilized with silver ions. The purpose of the modifications was to increase the surface hydrophilicity, alter the surface charge property or endue the surface with anti-bacteria function. The modified membranes were then examined for their anti-biofouling performance in terms of the anti-adhesion and anti-bacteria effects, with Escherichia coli pure culture and mixed culture bacteria in a bioreactor that simulated the activated sludge wastewater treatment process. The results clearly show that the hydrophilicity of a membrane, although important, is not an effective indicator for the tendency of membrane biofouling but the nature of the surface charges of the membrane also plays a very important role. It was found that the anti-adhesion approach that prevents the initial attachment of bacteria on a membrane surface is a more effective method than the anti-bacteria approach that aims at killing bacteria already attached on the membrane surface. The best performance for minimizing membrane biofouling has, however, been realized through a modified membrane surface that has effective anti-adhesion property plus additional anti-bacteria function, with the latter as a safe guard in case some bacteria do attach to the surface of a membrane. 相似文献
60.
The paper presents a new tool for the determination of inorganic speciation forms of aluminium: AlFn(3 − n)+, and Al3+ by means of the HPIC-FAAS. The proposed method has been successfully used for speciation analysis (qualitative and quantitative) of inorganic aluminium forms AlFn(3 − n)+ in soil samples. In order to isolate the most environmentally available fraction, 5 g of the sample was collected and extracted in deionised water (water soluble fraction) for 1 h using a magnetic stirrer. The determinations in a hyphenated technique system were performed for a number of prepared water extracts. Concentration determinations of particular aluminium forms were performed based on model studies and real samples. The separation of Al species with nominal charge of + 1, + 2, and + 3 required a run time of less than 4 min during a single analysis. Based on the analysis of water extracts of soil, it was obtained that aluminium forms elute in the following order: 1PA (first signal) — AlF2+ and/or AlF4−; 2PA (second signal) — AlF2+ and/or AlF30; 3PA (third signal) — Al3+. In order to confirm the occurrence of these forms a simulation using the Mineql program was conducted. The details of speciation analysis of aluminium fluoride forms by means of an HPIC-FAAS instrument equipped are presented. Interpretation of the speciation analysis of the water soluble fraction of soil samples is proposed, based on the separation during chromatographic run and calculated data by Mineql. 相似文献