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101.
This paper describes the formulation of a nonlinear mixed integer programming model for a large-scale product development
and distribution problem and the design and computational implementation of a special purpose algorithm to solve the model.
The results described demonstrate that integrating the art of modeling with the sciences of solution methodology and computer
implementation provides a powerful approach for attacking difficult problems. The efforts described here were successful because
they capitalized on the wealth of existing modeling technology and algorithm technology, the availability of efficient and
reliable optimization, matrix generation and graphics software, and the speed of large-scale computer hardware. The model
permitted the combined use of decomposition, general linear programming and network optimization within a branch and bound
algorithm to overcome mathematical complexity. The computer system reliably found solutions with considerably better objective
function values 30 to 50 times faster than had been achieved using general purpose optimization software alone. Throughout
twenty months of daily use, the system was credited with providing insights and suggesting strategies that led to very large
dollar savings.
This research was supported in part by the Office of Naval Research Contract N00014-78-C-0222, by the Center for Business
Decision Analysis*, by the University of Texas at Austin, and by the David Bruton, Jr., Centennial Chair in Business Decision
Support Systems. Reproduction in whole or in part is permitted for any purpose of the U.S. Government.
Center for Business Decision Analysis, Graduate School of Business — GSB 3.126, University of Texas, Austin, Texas 78712,
USA. 相似文献
102.
Three algorithms based on the bifurcation method are applied to solving the D4 symmetric positive solutions to the boundary value problem of Henon equation. Taking r in Henon equation as a bi- furcation parameter, the D4-Σd(D4-Σ1, D4-Σ2) symmetry-breaking bifurcation points on the branch of the D4 symmetric positive solutions are found via the extended systems. Finally, Σd(Σ1, Σ2) sym- metric positive solutions are computed by the branch switching method based on the Liapunov-Schmidt reduction. 相似文献
103.
李红 《邵阳高等专科学校学报》2008,(2):11-13
党的作风体现党的宗旨,影响党的形象,关系人心向背,涉及党和国家的生死存亡。作风建设是人自由全面发展的需要,是构建和谐社会的需要,是立党兴国的需要。加强党的作风建设,要坚持教育、制度、监督三管齐下,必须以加强机制建设为重点,为保障。 相似文献
104.
This paper addresses the problem of scheduling cascaded ‘blocked out’ continuous processing units separated by finite capacity
storage tanks. The raw materials for the product lines arrive simultaneously on the input side of the first unit. But every
unit can process only one product line at a time, thus giving rise to the possibility of spillage of raw material due to limited
storage capacity. The need to process multiple product lines and the added constraint of multiple intermediate upliftment
dates aggravate the problem. This problem is quite common in petrochemical industry. The paper provides a MINLP (Mixed Integer
Non-Linear Programming) formulation of the problem. However, for any realistic scheduling horizon, the size of the problem
is too large to be solved by standard packages. We have proposed a depth first branch and bound algorithm, guided by heuristics,
to help planners in tackling the problem. The suggested algorithm could output near optimal solutions for scheduling horizons
of 30 time periods when applied to real life situations involving 3 units and 3 product lines.
Preliminary version of the paper appeared in the proceedings of MISTA, 2005. 相似文献
105.
A series of acrylate monomers with alkoxy tails of varying lengths are synthesised and polymerised. The butoxy analogue had a stable enantiotropic cholesteric liquid crystalline phase which formed a grandjean texture when prepared as a thin film between glass slides. The polymer was mixed with a low molar mass nematic liquid crystal in various proportions and the pitch of the chiral nematic phases were determined using a cano‐wedge cell technique. The polymer prepared from (S)‐2‐(4‐butoxyphenyl‐4′‐benzoyloxy)‐1‐methyl ethyl acrylate had a pitch length of 113 nm which indicates that the polymer film could be employed in optical devices requiring selective reflection of light with short wavelengths in the region of 170 nm. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
106.
107.
Branch length similarity (BLS) entropy is defined in a network consisting of a single node and branches. In this study, we mapped the binary time-series signal to the circumference of the time circle so that the BLS entropy can be calculated for the binary time-series. We obtained the BLS entropy values for “1” signals on the time circle. The set of values are the BLS entropy profile. We selected the local maximum (minimum) point, slope, and inflection point of the entropy profile as the characteristic features of the binary time-series and investigated and explored their significance. The local maximum (minimum) point indicates the time at which the rate of change in the signal density becomes zero. The slope and inflection points correspond to the degree of change in the signal density and the time at which the signal density changes occur, respectively. Moreover, we show that the characteristic features can be widely used in binary time-series analysis by characterizing the movement trajectory of Caenorhabditis elegans. We also mention the problems that need to be explored mathematically in relation to the features and propose candidates for additional features based on the BLS entropy profile. 相似文献
108.
高校学生党建工作在新形势下取得显著成效的同时,也还存在学生入党动机多样化、部分学生党员理想信念缺失、高校党组织对学生党员的教育乏力等诸多“瓶颈”问题。对此,需要在高校学生党建工作中,通过着力加强党务工作队伍建设、着力提升学生党建工作的规范化水平、着力强化对学生党员的理想信念教育、着力丰富高校学生党建实践活动等,寻求“瓶颈”问题的突破,促进高校学生党建工作的健康发展。 相似文献
109.
乘积季节模型在商品房市场中的应用研究 总被引:5,自引:0,他引:5
主要采用时间序列乘积季节模型(随机季节模型与ARIMA模型的结合式)及多元统计方法,对商品房市场的发展规律进行了研究.通过对合肥市2001年至2005年60个月份的月度商品房销售面积进行实证分析,建立了一个商品房市场销售规律的统计预测模型ARIMA(0,1,1)×(0,1,1)12,并对该模型进行适应性检验,得到较好的结果.最后,利用该模型对该市的房地产发展趋势进行了预测. 相似文献
110.
高校党委必须结合自身特点贯彻“三个代表”的重要思想,这是由高校党委的历史使命所决定的。文章从如何使高校成为代表先进社会生产力发展求的主战场,成为弘扬社会主义先进文化的前沿阵地,成为培养四有新人的摇篮第三个方面进行了论述。 相似文献