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981.
Abraham Mehrez Zilla Sinuany-Stern Alan Stulman 《The Journal of the Operational Research Society》1986,37(10):971-977
In this note, we examine the algorithm of Drezner and Wesolowsky for locating a facility with maximin rectilinear distance to a given set of demand points. The concept of the closest-point constraint is introduced as a technique for increasing the efficiency of the algorithm. This potential increase in efficiency is demonstrated by an example. 相似文献
982.
J D Griffiths Z F Lawson J E Williams 《The Journal of the Operational Research Society》2006,57(12):1413-1424
Advances in recent treatments for HIV/AIDS patients have shown dramatic outcomes in extending the incubation period and AIDS survival time, while also providing significant improvements in the quality of patients' lives. A compartmental model is proposed to analyse the effects of the various treatment regimens which have been introduced. The results produced are in good agreement with routinely collected data relating to levels of HIV/AIDS incidence and prevalence in the UK homosexual population. Some parameter values within the model are obtained from surveys, census results, etc, but others are derived using a maximum likelihood estimation procedure. Finally, the model is used to project levels of incidence and prevalence over the next few years, and to investigate several possible scenarios. 相似文献
983.
The energy exchange between the pumping laser and FIR signal in the optically pumped FIR laser (OPFIRL) system was studied. The iteration method has been used to calculate the power density of the pumping and FIR signals at any point along the optical axis of the sample tube. It was found that the power density of the FIR signal did not always increase along the length of the laser tube. There was a maximum FIR power density at the appropriate point in the sample tube. If the distance of maximum power point from the entrance of the OPFIRL tube was taken as the length of sample tube Zopt, the maximum FIR laser output should be obtained. This was the optimum length of OPFIRL tube. The value of Zopt was closely related to the parameter of OPFIRL such as the pumping power density, the pumping detuning and the frequency of the FIR laser. The energy-exchange and the maximum output of the fir laser were calculated under the ideal condition. 相似文献
984.
林正国 《华东理工大学学报(自然科学版)》1986,(1)
引用带权的Sobolev模和牛顿迭代格式,讨论了拟线性对称双曲抛物耦合方程组的初边值问题,得到了可微解的存在和唯一性定理。 相似文献
985.
In this article, local optimality in multiobjective combinatorial optimization is used as a baseline for the design and analysis
of two iterative improvement algorithms. Both algorithms search in a neighborhood that is defined on a collection of sets
of feasible solutions and their acceptance criterion is based on outperformance relations. Proofs of the soundness and completeness
of these algorithms are given. 相似文献
986.
葛仙米对丁草胺胁迫的响应 总被引:2,自引:0,他引:2
研究了丁草胺对可食用蓝藻葛仙米(Nostoc sphaeroides)生理和代谢活性的影响.用不同浓度的丁草胺处理葛仙米,结果显示低浓度(5 mg·L-1)丁草胺使其光合作用、呼吸作用和光合系统Ⅱ活性增强,高浓度丁草胺(>5 mg·L-1)限制其光合作用、呼吸作用和光合系统Ⅱ活性.同时丁草胺对葛仙米膜结构和功能具有破坏作用,随着丁草胺处理浓度增大,质膜透性不断增大,丙二醛和超氧自由基阴离子含量升高;在低浓度丁草胺处理时,类胡萝卜素含量增加,超氧化物歧化酶(SOD)活性增强,高浓度丁草胺处理时,类胡萝卜素含量降低,SOD活性下降;表明葛仙米对低浓度的丁草胺胁迫具有一定的耐受能力,但高浓度的丁草胺对其生理和代谢构成威胁;针对目前葛仙米野生生境中丁草胺的用量,建议限制丁草胺在葛仙米产地的使用,以保护日益稀缺的葛仙米资源. 相似文献
987.
We prove the vanishing of the Koszul homology group H
μ(Kos(M)μ), where μ is the minimal number of generators of M. We give a counterexample that the Koszul complex of a module is not always
acyclic and show its relationship with the homology of commutative rings. 相似文献
988.
蔺琳 《辽宁师专学报(自然科学版)》2005,7(2):6-7,15
从认知结构、认知规律、策略模式及非智力因素四个方面阐述了数学教学中如何有效地培养学生解题能力的问题. 相似文献
989.
990.
Anil Kumar Karn 《Positivity》2007,11(2):369-374
An error has been detected (and also corrected) in Theorem 2.8 of the paper entitled “Adjoining an Order Unit to a Matrix
Ordered Space” (Positivity, (2005)9: 207–223; DOI ). Accordingly, some of the results of the paper have been modified. Also, a notion of C*-matricially, Riesz normed spaces has been introduced. 相似文献