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1.
遗传优化算法及含有模糊目标和模糊约束的机械优化设计   总被引:1,自引:0,他引:1  
针对机械工程中的非线性约束优化的工程问题 ,提出了一种新的遗传算法。该方法在遗传算法中通过去掉等式约束、构造浮点型编码向量、精心设计动态遗传及变异算子等改造操作 ,较大地提高了寻优效率和寻优能力 ,并用Matlab语言开发了相应软件。对设计的算法与一般遗传算法、变尺度法以及随机搜索方法进行算例比较。对于含有模糊目标和模糊约束冗余系统可靠性优化设计问题 ,通过定义隶属函数 ,把问题转化为清晰的普通优化问题利用改进的算法求解 ,以提高求解的精度和可靠性  相似文献   

2.
提出一种改进的遗传算法用于求解机械手运动学逆问题 .该算法采用实数编码 ,其交叉概率和变异概率根据解的适应度函数值自适应调整 .计算机仿真结果显示 ,该算法较简单遗传算法 (SGA)求解精度高 ,收敛速度快且稳定性能好 .  相似文献   

3.
混合多目标遗传算法在电力系统经济调度中的运用   总被引:2,自引:0,他引:2  
针对电力系统经济调度问题的多目标特性,提出了一种混合多目标遗传算法.算法除了改进传统目标函数加权法使之更适于多目标优化问题之外,还利用模糊逻辑技术来自适应调整交叉概率、交叉点位置以及变异概率,使算法具有优良的收敛性能.  相似文献   

4.
为解决在密集目标环境和出现交叉航迹的情况下,航迹的统计关联方法关联正确概率降低,不能准确地对目标航迹进行正确相关的问题,根据传统的模糊双门限航迹关联方法,将非隶属度函数引入其中,提出了一种基于直觉模糊的双门限航迹关联算法。根据关联特点,确立了隶属度函数和非隶属度函数;利用蒙特卡洛仿真,对2部雷达观测的存在交叉的航迹进行关联,并与传统的模糊双门限航迹关联算法进行了对比,结果表明:在密集航迹情况下,该算法相比传统的模糊双门限航迹关联算法正确关联概率从45.1%提高至49.8%,该改进算法能够更好地适应密集航迹的关联。  相似文献   

5.
遗传优化算法及含有模糊目标和模糊约束的机械优化设计   总被引:8,自引:0,他引:8  
针对机械工程中的非线性约束优化的工程问题,提出了一种新的遗传算法。该方法在遗传算法中通过去掉等式约束、构造浮点型编码向量、精心设计动态遗传及变异算子等改造操作,较大地提高了寻优效率和寻优能力,并用Matlab语言开发了相应软件。对设计的算法与一般遗传算法、变尺度以及随机搜索方法进行算例比较。对于含有模糊目标和模糊约束冗余系数可靠性优化设计总是,通过定义隶属函数,把问题转化为清晰的普通优化问题利用改进的算法求解,以提高求解的精度和可靠性。  相似文献   

6.
针对遗传算法在求解车辆调度问题时容易出现早熟现象,导致求解精度不高的问题,本文用混合算法构建了物流配送总成本最小的目标函数。首先,定义了车辆调度问题的数学模型,在此基础上提出了一种遗传算法中对交叉和变异概率的自适应调整的方法。其次,通过局部搜索算法求得初始解,采用遗传算法初始解优化,并且在配送时刻改变以后,利用TS算法搜索最优解迅速的特点改进配送方案,最终求得配送时刻不断变化下的车辆调度方案。最后通过算例分析,得到本文提出的算法与单一局部搜索算法和单一TS算法相比,在求解精度、求解时间方面都具有更大的优越性。  相似文献   

7.
针对带硬时间窗的关联运输调度问题(Incident Vehicle Routing Problem with Hard Time Windows,IVRPHTW),联系实际应用中危险品的车辆路径问题,介绍了混沌遗传算法的基本原理,并对其进行改进,自适应地调整交叉概率和变异概率,引进了模拟退火机制,并用改进的算法来对IVRPHTW求解,然后与遗传算法求解此模型的结果相比较。实例证明该算法求解危险品的关联运输调度问题是可行的,且优于传统的遗传算法。  相似文献   

8.
舰艇编队防空火力基于改进遗传算法的分配方案   总被引:5,自引:1,他引:4  
描述了舰艇编队防空火力分配问题,建立了火力优化分配模型。结合舰艇编队防空作战的特点,分析了几种传统分配算法的不足。为了获得全局最优解,将遗传算法用于该火力分配优化研究中。针对标准遗传算法计算费时、稳定性差等不足,从初始群体均匀产生、适应度尺度变换、稳态繁殖、自适应遗传参数等方面作了改进,给出了基于改进遗传算法的模型求解方法和步骤。经过实例计算,取得了良好的分配效果,可为制定舰艇编队防空作战指挥自动化决策提供科学、有效的支持。  相似文献   

9.
具有禁忌算子的遗传算法目标优化分配   总被引:4,自引:2,他引:4  
针对地面防空作战中的多通道目标优化分配问题,给出了一种具有禁忌算子的混合遗传算法。该算法结合禁忌搜索算法和遗传算法二者的优点,既克服了禁忌算法全局搜索能力的不足,又提高了遗传算法的爬山能力,还解决了遗传算法容易陷入局部最优的问题,并使搜索过程具有记忆功能。仿真结果表明,该算法可有效给出求解多通道目标优化分配问题的满意解。  相似文献   

10.
针对板坯入库优化决策问题,采用隶属度函数表示待入库板坯长度、宽度、厚度与各库位已存板坯对应属性的匹配程度,建立了板坯入库模型.针对问题特征,借鉴遗传算法的交叉和变异操作,设计了一种混合离散粒子群算法(DPSO--CM)进行求解.基于企业实际生产数据的仿真实验验证了模型和算法的可行性和有效性.  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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