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1.
应用分枝定界技术将二次整数规划问题变量X=(x1,x2,…,xn)分开,选取一个分量xi固定,然后求解具有n-1个变量的整数规划问题,并应用分枝定界技巧,使节点([xi]±k)的个数最少,并找出判断节点个数最少的条件.  相似文献   

2.
整数规划是规划论中较新的一个分枝,它是研究决策变量取整数的一类线性规划,主要的解法有割平面法和分枝定界法两种.对它们进行介绍后,通过求解具体问题进行分析比较.  相似文献   

3.
通过对整数规划问题的算法Groebner基和分枝定界法的求解过程分析比较,以同样整数规划问题实例,采用数学软件Maple,用Groebner基方法和分枝定界法分别进行了求解,对求解的的效率进行了比较,并对影响效率的原因进行了讨论.  相似文献   

4.
本文将修正的Dakin分枝定界法用于求解带有线性分式目标的混合整数多目标规划问题,提出了“弹性约束”的概念及其处理方法和交互型分枝定界的两步算法,并将其应用于实际问题中。  相似文献   

5.
讨论了形如Pm|res sh,p=1|Cmax离散型多资源排序问题,这一问题等价于一类整数规划问题,给出了一个求解基本向量的分枝定界算法。  相似文献   

6.
对于两层决策问题的现有研究,主要集中于连续变量和单目标函数情形,但现实世界大量存在着含整数变量两层多目标决策问题。本文考察了一类特殊的含整数变量两层多目标决策问题:上层存在0-1决策变量、下层有多个目标函数。在定义了问题的独立决策解与合作解后,本文将设计一种有效的分枝定界算法,它能以较少的节点求得问题的解。  相似文献   

7.
对求解整数规划方法的新探索   总被引:4,自引:0,他引:4  
借鉴分枝定界法求解整数规划的基本原理和目标排序法求解0-1规划的思路,在完成一系列理论分析和证明之后,提出求解整数规划的简捷有效的新方法-松驰最优解邻域整点搜索法。  相似文献   

8.
设S={x1,…,xn}是由n个不同正整数组成的集合.第i行j列元素为xi和xj的最小公倍数[xi,xj]的n×n阶矩阵([xi,xj])称为定义在S上的LCM矩阵.如果对所有的1≤i,j≤n,有(xi,xj)∈S,称S是最大公因子封闭的(gcd closed).作者考虑了方程11+1(y2,y3)=0[y1,y2,y3,y4]-∑4(y1,y3)+1(y1,y2)+1yii=1的二次幂整数解,证明了对于给定的整数x,如果用ω(x)表示x的不同素因子的个数并令y=[y1,y2,y3,y4],那么当ω(y)<4时,方程没有t(≥2)次幂整数解,并且给出ω(y)=4时方程有二次幂整数解的必要条件.进一步证明了y≤1334025时方程无二次幂整数解.  相似文献   

9.
对于两层决策问题的现有研究,主要集中于连续变量和单目标函数情形,但现实世界大量存在着含整数变量两层目标决策问题,本文考察了一类特殊的含整数两层多目标决策问题:上层存在0-1决策变量、下层有多个目标函,在定义了问题的独立决策解与合作解后,本文将设计一种有效的分枝定界算法,它能以较少的节点求得问题的解。  相似文献   

10.
搜索图的最大团是经典的NP-难题。通过运用二次0-1规划模型(简称Q0-1规划模型)寻得最大团问题的解法,所用的分枝定界法建立在此模型之上。通过一个命题推导出图的最大团求解问题与一类特殊Q0-1规划的等价性,借助于求解一般Q0-1规划的分枝定界法推演出求最大团问题的分枝定界规则,从而将图论中的经典问题转化成代数问题加以解决,并给出实例说明该算法的有效性。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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