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凹整数规划的分枝定界解法 总被引:3,自引:0,他引:3
凹整数规划是一类重要的非线性整数规划问题,也是在经济和管理中有着广泛应用的最优化问题.本文主要研究用分枝定界方法求解凹整数规划问题,这一方法的基本思想是对目标函数进行线性下逼近,然后用乘子搜索法求解连续松弛问题.数值结果表明,用这种分枝定界方法求解凹整数规划是有效的. 相似文献
35.
采用文献资料法、数理统计法、比较法对吉林省民办高校和公立高校体育教师的科研现状进行比较分析,比较二者不同年龄、学历、职称的教师发表论文状况,分析二者的科研学术氛围及科研条件,旨在了解长春市两类高校的体育科研的现状,为长春市高校体育科研水平的提高提供参考。 相似文献
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David Morris 《Applied biochemistry and biotechnology》2004,113(1-3):5-12
This article addresses two questions: Has the effectiveness of the US governments federal research and development (R&;D) spending suffered from the post-1980 strategic change from freely shared and publicly owned to privately owned scientific advances? What criteria would a federal R&;D program use to design a strategy that most effectively enhances the well-being of farmers and rural communities? Several studies found that the pre-1980 US Department of Agriculture research strategy was very effective. No comparable studies have analyzed the comparative effectiveness of the post-1980 strategy of restricting access to the results of public research. Recent experience and several analytical studies suggest that to significantly enhance the health of rural economies from an expanded use of plant matter as an industrial material, federal policy should channel scientific and engineering research into small- and medium-sized production and processing technologies and should encourage farmer-owned, value-added enterprises. 相似文献
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Finding finer functions for partially characterized proteins by protein-protein interaction networks
LI YanHui GUO Zheng MA WenCai YANG Da WANG Dong ZHANG Min ZHU ding ZHONG GuoCai LI YongJin YAO Chen WANG Jing 《科学通报(英文版)》2007,52(24):3363-3370
Based on high-throughput data, numerous algorithms have been designed to find functions of novel proteins. However, the effectiveness of such algorithms is currently limited by some fundamental factors, including (1) the low a-priori probability of novel proteins participating in a detailed function; (2) the huge false data present in high-throughput datasets; (3) the incomplete data coverage of functional classes; (4) the abundant but heterogeneous negative samples for training the algorithms; and (5) the lack of detailed functional knowledge for training algorithms. Here, for partially characterized proteins, we suggest an approach to finding their finer functions based on protein interaction sub-networks or gene expression patterns, defined in function-specific subspaces. The proposed approach can lessen the above-mentioned problems by properly defining the prediction range and functionally filtering the noisy data, and thus can efficiently find proteins’ novel functions. For thousands of yeast and human proteins partially characterized, it is able to reliably find their finer functions (e.g., the translational functions) with more than 90% precision. The predicted finer functions are highly valuable both for guiding the follow-up wet-lab validation and for providing the necessary data for training algorithms to learn other proteins. 相似文献
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The controlling factors and distribution prediction of H2S formation in marine carbonate gas reservoir, China 总被引:1,自引:0,他引:1
ZHU GuangYou ZHANG ShuiChang LIANG YingBo 《科学通报(英文版)》2007,52(A01):150-163
Generally, there are some anhydrites in carbonate reservoir, as H2S is also familiar in carbonate oil and gas reservoirs. Nowadays, natural gas with high H2S concentration is usually considered as TSR origin, so there is close relationship between H2S and anhydrite. On the contrary, some carbonate rocks with anhydrite do not contain H2S. Recently, researches show that H2S is only a necessary condition of H2S formation. The reservoir porosity, sulfate ion content within formation water, reservoir temperature, oil/gas and water interface, hydrocarbon and some elements of reservoir rock have great controlling effects on the TSR occurrence. TSR deoxidizes hydrocarbon into the acidic gas such as H2S and CO2, and the H2S formation is controlled by TSR occurrence, so the relationship among reaction room, the contact chance of sulfate ion and hydrocarbon, the reservoir temperature has great influence on the TSR reaction. H2S has relatively active chemical quality, so it is still controlled by the content of heavy metal ion. Good conditions of TSR reaction and H2S preservation are the prerequisite of H2S distribu- tion prediction. This paper builds a predictive model based on the characteristic of natural gas reservoir with high H2S-bearing. In the porosity reservoir with anhydrite, the formation water is rich in sulfate and poor in heavy metal ion. Oil and gas fill and accumulate in the gas reservoir with good preservation conditions, and they suffered high temperature later, which indicates the profitable area of natural gas with high H2S-bearing. 相似文献
39.
求线性规划初始可行基的新方法 总被引:9,自引:3,他引:6
本文提出一个求线性规划初始可行基的新算法,该算法不仅避免了人工变量,而且理论分析及初步的数值实验结果表明其效率更高。 相似文献
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