首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
基于退火不可行度的约束优化问题遗传算法   总被引:4,自引:0,他引:4  
传统的遗传算法在求解带约束的数值优化问题时,主要采用罚函数法.本文针对罚函数法在实际应用中的困难和不足,提出了基于退火不可行度的遗传算法来处理各类约束优化问题.仿真结果表明该方法是一种有效的约束问题寻优算法.  相似文献   

2.
对模糊数学规划的目标函数取大∨与取小∧的问题,给出了一种求解方法——约束域分割法,此法对约束集凹集的数学规划问题亦有效。  相似文献   

3.
提出了一种求解二次规划的新算法,该算法采用单调性分析技术建立作用约束集,将一般二次规划问题转化为等式约束二次规划问题,并用简约梯度法的思想求解之,通过解一系列的等式约束问题去逼近原问题的最优解,考核结果表明,该算法及相应的软件是成功的。  相似文献   

4.
对约束函数单调而目标函数非单调的规划问题,给出了目标函数的1种新的单调化变换公式.先引入极大熵函数,将多个约束的非线性规划问题,转化为只含1个约束的规划问题,再将转化后的只有1个约束的规划问题转化为1个等价的单调规划问题.  相似文献   

5.
给出一种整系数多项式01整规划的两个连续化途径,在不增加变量的前提下,能将整系数多项式01整规划问题转化成无约束多项式规划问题.所给方法能够直接处理不等式约束情形,而不需先将不等式约束转化成等式约束再来处理.  相似文献   

6.
基于FDM-TDM的V/UHF地空战术数据链研究   总被引:3,自引:3,他引:3       下载免费PDF全文
目前的V/UHF地空战术数据链主要以固定时隙分配模式工作,存在着用户容量与信息刷新速率之间的矛盾。针对这一问题,结合新一代地空战术数据链的需求,通过分析空中态势信息和指挥引导信息的传输和要求,提出了一种基于FDM-TDM的V/UHF地空战术数据链传输方案,该方案在保证较高信息刷新速率情况下,可使指挥引导飞机容量增加5倍以上。  相似文献   

7.
本文利用拟可微函数的性质,构造了两种不同的方法,建立了带约束的拟可微多目标规划的最优性条件。方法一是将带约束的多目标规划问题化为无约束的多目标规划问题;方法二是将带约束的多目标规划问题化为带约束的单目标规划问题。  相似文献   

8.
首先根据非线性规划最优解的KT条件,给出一种含参数不等式约束的非线性规划最优解的存在条件,建立相对增量比与较优解的概念,应用摄动梯度投影方法,针对工程优化设计中具有模糊约束非线性规划的模糊优化问题,构造了一种相对增量比准则摄动梯度投影的普通优化算法,为求解模糊优化问题提供了一种新的途径。  相似文献   

9.
讨论了线性混合整数规划问题(LMIP)的罚函数及其连续化途径。通过构造一种罚函数化有约束的LMIP为无约束或简单约束的LMIP。进而给出一种连续化方法,把其化为一个连续的、易解的规划问题。提供了一种求解LMIP的较通用的方法。  相似文献   

10.
一类双约束最短路问题的近似算法   总被引:1,自引:0,他引:1  
带时间和边数约束的双约束最短路问题是NP-完备的。它的一种拟多项式精确算法可以利用动态规划方法给出,在此基础上采用rounding和scaling的处理技术得到了一种全多项式时间近似方案(FPAS)。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
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   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号