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1.
三维几何约束的序列二次规划求解   总被引:3,自引:0,他引:3  
归纳总结出了三维几何约束形式,并用数学形式进行表达,然后把约束违反量当作优化目标,通过求解约束梯度,用序列二次规划法使约束违反量趋近于零来求解约束。这种方法避免了严格的方程组的建立,无论约束是否合理,冗余,欠缺,此算法都将给出一个最符合设计者意图的解。  相似文献   

2.
针对变分不等式的带非负约束的转化形式给出了一类信赖域迭代算法.该方法的特点是通过利用内点技术,将带非负约束的信赖子问题转化成约束形式的信赖域子问题,从而可以利用截断共轭梯度法来近似求解.  相似文献   

3.
给出了一个新的求解约束的方法──动态约束算法.它通过引入新的约束类型,使变量操作和约束操作算法统一起来.在新的求解约束过程中,不需再区分变量与约束.  相似文献   

4.
多工况下复杂杆系结构的截面优化研究   总被引:1,自引:0,他引:1  
根据复杂杆系结构的特点,将约束函数分为局部约束和全局约束,提出了一种用于约束函数处理的简化方法,该方法是利用约束违反程度系数将约速函数归一化,并形成统一约束函数,然后用相对差商法求解经过简化后的数学模型。通过对结构优化算例的计算,说明雇中大幅度提高算效率。  相似文献   

5.
批量及路径可变时机器ROBUST布置问题   总被引:2,自引:0,他引:2  
应用混合遗传算法(HGA)解决了生产批量及路径可变时的车间ROBUST布置问题,即用遗传算法找到一种车间布置,它在各个生产时期都是最优或接近最优的.对遗传算法操作中产生的违反约束的个体采用修补和动态惩罚相结合的处理方法,即对变异操作产生的违反约束的个体采用修补的方法,同时在目标函数中引入惩罚函数控制种群中违反约束的个体数目,并设计了一个模糊控制器动态地调整惩罚系数,以解决遗传算法中的约束满足问题,提高了遗传算法的效率.仿真结果表明,所提出的动态调整惩罚系数的思想及方法是提高遗传算法效率的一种有效途径.  相似文献   

6.
对外贴FRP(纤维增强复合材料)加固钢筋混凝土梁抗弯极限承载力的求解问题,ACI440F规范及我国CECS146:2003规程都给出了相应的求解公式,但均为验算形式.这在面向设计,即计算给定目标承载力下的FRP用量时,并不方便.针对矩形截面形式,通过引入原构件配筋特征参数和FRP配筋特征参数,推导出量纲-形式的弯矩增量与参数之间的关系表达式,并给出显式求解FRP用量的计算方法.在此基础上,进一步通过定义截面形状系数,将这一显式求解方法推广至T形及更为一般性的截面形式.  相似文献   

7.
提出一种求解约束优化问题的修正选择粒子群优化算法(RSPSO).在这个算法中,利用动态多阶段罚函数方法处理约束,并加入一种违反约束的修正选择策略,采用线性递减违反约束容忍度来引导粒子,即利用修正的可行基规则来更新个体极值和全局极值,指引粒子迅速飞向可行域;考虑到粒子群中每个粒子周围的局部信息对它未来飞行的影响,改进了基本粒子群优化的速度方程.数值结果表明,所提出的算法求解约束最优化问题具有较高的计算精度、较好的稳定性和较强的全局寻优能力.  相似文献   

8.
针对传统差分算法在求解约束优化问题时存在收敛速度慢、精度低等问题,本文提出了一种基于半角距离变化的改进差分进化算法(HDDE)﹒首先,由父代产生2个子代,并利用可行性规则选出最好的子代;其次,对所选最优子代进行约束违反度预处理,即当其满足半角距离变化时,计算出子代的真实约束违反度,否则子代的约束违反度为无穷;最后,若经过预处理的子代约束违反度小于父代的约束违反度,便使用可行性规则进行比较,否则保留父代﹒通过对12个基准约束优化问题进行仿真研究,结果发现:相较于对比算法,HDDE算法的收敛时间最短,为0.216s;在精度方面,该算法有5个测试集的标准差为0,这说明所提算法具有更好的性能.  相似文献   

9.
配电网重构与电容器的配置   总被引:1,自引:0,他引:1  
配电网与输电网不同,一般是辐射型树状结构,其支路参数中R与X相差不大,有时甚至R>X.必须采用特殊的潮流分析方法.利用配电网络重构的改进支路交换算法进行快速求解,增加了电客器配置功能以提高结点的电压,既解决电压越限问题,同时又进一步降低网损.在网络重构的实际运行约束下,以补偿电容为控制量,母线电压为被控量,利用线性规划法求解电容器配置问题.算法简单实用,可用于离线环境.  相似文献   

10.
一类二维耦合量子谐振子的求解   总被引:1,自引:0,他引:1  
运用广义线性量子变换理论,对一类二维耦合量子谐振子进行求解,给出了该系统演化算子的普通形式、正规乘积形式、反正规乘积形式、演化算符的矩阵元、波函数和力学量期望值.  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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