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1.
劣质绝缘子电场正问题优化算法分析   总被引:2,自引:0,他引:2  
针对劣化绝缘子的电场法检测中绝缘子电场计算精度低的问题,提出基于遗传算法优化的模拟电荷法进行高压静电场计算,给出了优化方法原理、可行性分析,建立了绝缘子电场计算目标函数及优化模型,并进行了绝缘子串周围电场的计算分析.分析结果表明,将绝缘子串周围检测点电位作为目标函数,应用遗传算法优化模拟电荷的电荷量,可更好地对目标函数进行全局寻优,提高了模拟电荷法的寻优速度、绝缘子串周围电场的计算精度以及绝缘子串中劣质绝缘子诊断的准确度.  相似文献   

2.
以分形几何生成理论为基础,研究并发展基于迭代函数系统IFS的分形几何在纺织纹理设计方面的应用。通过对IFS进行研究,讨论IFS所生成的分形图案的形貌和数学参数关系。特别是对基于仿射变换的IFS所生成分形图案的控制条件,建立一个实际的分形艺术图案生成模型;然后,整合IFS生成模型与计算方法,发展分形图案生成系统;最后,将分形图案生成系统所得的图案应用在纺织纹理设计上。  相似文献   

3.
基于多指标特征迷彩伪装效果的评价与设计   总被引:1,自引:0,他引:1  
针对提高迷彩伪装的效果,根据视敏度曲线、人眼分辨率和可见度、canny算子检测的边缘图像、灰度方差函数、层次分析法方法,分别构建了灰度方差函数、层次分析等模型,结合MATLAB软件等,得到迷彩斑块最理想的颜色搭配、形状、尺寸和清晰度.建立了分析各种迷彩伪装效果模式的方法,定量和定性迷彩伪装效果评价方法,并设计一个适用最广泛的迷彩伪装模式.  相似文献   

4.
建立了一个注塑模浇口位置设计的多目标优化模型,以浇口位置作为设计变量,优化充填过程中入口压力、温度分布等主要工艺参数以减小制品的翘曲程度.将拟精确罚函数和基于信息熵的多种群离散变量遗传算法相结合,发展了一种求解注塑模浇口位置多目标优化问题的迭代格式.在遗传进化中采用了多种群遗传策略和基于信息熵的空间减缩搜索技术,从而大大提高了遗传进化的效率.将该算法与注塑模流动数值模拟程序结合进行浇口位置优化设计.算例表明所提出的方法适用于注塑模浇口位置优化,并且有较好的计算效率和精度.  相似文献   

5.
针对锅炉汽包水位的强非线性及虚假水位现象,研究了基于模糊模型的预测控制方案.在模糊建模中,采用模糊聚类法求取规则前提部分模糊集合的隶属函数,采用相似性算法清除冗余模糊集合,以获得规则简化、具有良好逼近能力的模糊模型.为了解决非凸优化问题,采用遗传算法进行目标函数优化;结合预测控制的特点,设计了适合于预测控制的遗传算法.试验结果证明了该方案是有效的.  相似文献   

6.
本文介绍了一种新的串级系统优化设计方法.它结合串级控制系统模型,以典型的性能指标为目标函数、以调节器设计参数的取值范围等为约束条件建立了参数优化数学模型,然后用遗传算法求解优化参数.数值实验表明了本方法的有效性.  相似文献   

7.
对不确定结构的区间可靠性进行了研究,建立了基于区间可靠性的优化设计模型.采用结合嵌套遗传算法和径向基函数神经网络的模型,进行区间的直接优化,解决了基于区间可靠性的优化设计求解问题,避免了间接模型的复杂转换过程.充分考虑了实际工程中设计向量存在扰动的情况,提出了该情况下目标函数波动的约束,使目标函数和约束函数在扰动下依然满足可靠性要求.通过数值算例验证了模型的有效性和优越性.将所提出的模型用于具有区间不确定参数的行车平板优化,结果表明了所提方法的可行性和工程有效性.  相似文献   

8.
通过MATLAB编码图案控制Computer Simulation Technology (CST) Microwave Studio计算模拟软件,针对电磁超材料吸收器正向设计只能基于规则图案的现状,采用遗传算法对超材料吸收器进行逆向设计研究.以自动仿真为基础,用CST计算随机不同的初始图形结果,然后在遗传算法中迭代优化,不断用CST计算新出现图形的吸收率,最后优化出吸收率高的吸收器.首先进行单目标遗传算法优化设计吸收器,结果表明,在各个太赫兹波段,最高吸收峰的吸收率均大于96%,次高峰大于94%,平均吸收率均大于87%.然后进行多目标遗传算法优化设计,不再局限于一个单独的吸收率指标,能够加上如非目标波段的低吸收率的性能指标,实现单频吸收的功能.  相似文献   

9.
研究了基于遗传算法的无人机全局路径规划算法,建立了综合评价航程总长度、威胁概率和平均地形高度的多目标优化函数,并针对此优化函数设计了基于相对距离转角的遗传算法编码方案,进化计算结果稳定,达到了利用三维地形规避威胁的目的.进而研究了基于路径规划点生成光滑航迹的鲁棒性算法,利用MATLAB和VRML接口实现了无人机全局航迹...  相似文献   

10.
该文从提高民间装饰图案的视觉传达能力的角度出发,需要进行图像纹理智能匹配处理,提出一种基于视觉传达的民间装饰图案纹理智能匹配方法,构建视觉传达下的民间装饰图案纹理智能信息采集模型,采用图像自动成像技术进行民间装饰图案的纹理成像和特征分割,提取典型民间装饰图案和民族设计语言的纹理直方图,根据直方图分布在视觉传达下进行纹理分割和自动匹配,采用正则化特征融合方法进行民间装饰图案纹理信息增强和优化检测,提取民间装饰图案的边缘轮廓特征点,以提取的装饰图案边缘轮廓特征点作为输入统计信息进行纹理匹配。采用该方法进行民间装饰图案纹理匹配的自适应性能较好,纹理分辨能力较强,提高现代视觉传达设计中更好地体现民间装饰图案的应用研究,推动传统文化元素和现代设计创新性结合。  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.
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   

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 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   

15.
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   

16.
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   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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