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1.
在基于量子粒子群算法的基础上,提出一种混合细菌觅食的优化算法,通过对七个基准函数的实验仿真,比较两种方法求解整数规划问题.实验表明,基于量子粒子群的细菌觅食算法搜索成功率较高,综合搜索效率更高,收敛较快,为求解整数规划问题提供一种更优的可靠途经.  相似文献   

2.
提出了一种改进的量子粒子群算法,并将该算法用于求解非线性混合整数规划问题。构造了一种自适应调整的惯性权重,平衡了算法的全局搜索和局部搜索能力;针对混合整数规划问题,给定一定比例的初始可行解,提高了初始种群解的多样性;利用协同进化选择策略,对种群中的不可行解重新生成,使种群中每个粒子的信息充分利用,从而提高算法的收敛速度;为了抑制算法的早熟现象,给出了一种新的混沌搜索方式,对全局最优解进行局部搜索,增强算法的局部搜索能力。通过16个常见的测试函数测试结果表明,改进的量子粒子群优化算法对求解非线性混合整数规划问题,在成功率和精度方面得到很大的提高。  相似文献   

3.
利用混合细菌觅食算法(PO-BFA)求解整数规划问题,并与量子粒子群算法(QPSO)的求解结果进行对比。经过适当的参数设置混合细菌觅食算法可以有效地解决整数规划问题,在搜索过程中没有出现早熟现象,而且PO-BFA在求解整数规划问题上的整体性能比QPSO更优。  相似文献   

4.
针对柔性作业车间调度问题,提出一种改进模拟退火算法来进行求解。该算法引入粒子群算法中的基于位置取整和基于轮盘赌两种个体编码方法,并采用3种不同的局部搜索方法来构造个体的邻域结构。算例计算表明,改进模拟退火算法在求解柔性作业车间调度问题时,比粒子群算法、混合粒子群算法以及模拟退火算法具有更好的求解性能,其中采用轮盘赌编码时,算法的求解性能要优于采用位置取整时的求解性能,且基于互换的局部搜索方法要优于其他两种局部搜索方法,能更有效地改善算法的求解性能。  相似文献   

5.
基于粒子群算法的整数规划问题的求解算法   总被引:3,自引:0,他引:3  
整数规划是运筹学的一个分支,一直以来没有很好的求解算法.目前有研究人员尝试用粒子群算法求解整数规划,但都只能解决无约束整数规划问题.提出了一种求解约束整数规划的粒子群算法,能够解决有约束线性和非线性整数规划问题.  相似文献   

6.
为了求解整数约束和混合整数约束优化问题,提出了简化二阶震荡粒子群优化算法.在二阶震荡粒子群算法的基础上,对更新过程进行简化,使得迭代方程由原来的二阶降成一阶,粒子的搜索过程更为简单高效,便于搜索和寻优;引入了平均个体最优位置,使得所有粒子的有效信息被充分利用;对不满足约束条件的粒子重新生成,从而加快算法的收敛速度;为了防止算法的早熟收敛现象,提出了"优胜劣汰"的更新机制.最后,为了验证算法求解整数和混合整数优化问题的可行性和有效性,将简化二阶震荡粒子群混合算法对16个测试函数进行了测试并与其他三种算法比较.实验结果表明,本文算法在精确度和成功率方面有明显的提高.  相似文献   

7.
针对0-1背包问题(0-1KP)的特点,以经典的速度-位移模型为基础整数编码各粒子,以混沌序列指导全局搜索,以排列的改变描述粒子的飞行.更新粒子的位置,进而提出用于求解0-1KP的整数混沌粒子群优化(ICPSO)算法.该算法由于背包容量的限制,融入到编码和粒子飞行中,因而不会在进化中产生无效的粒子,从而提高了算法的求解效率.实验结果表明:ICPSO算法简明、有效,较典型遗传算法,及粒子群算法具有更好的收敛性能和求解速度.  相似文献   

8.
为了求解非线性混合整数规划问题,提出了一种基于随机游走的粒子群优化算法(RWPSO).构造出自适应的惯性权重,平衡了算法的全局和局部搜索能力;提出了一种"随机游走"行为,增强粒子的局部寻优能力;为了防止算法出现早熟收敛现象,提出了"优胜劣汰"更新机制.最后,为了验证算法在求解非线性混合整数规划问题方面的可行性和有效性,将提出的算法用16个常用的测试函数进行了测试并与其他3种算法比较.实验结果表明,RWPSO算法在精确度和成功率方面得到了很大的提高.  相似文献   

9.
针对非线性方程组求解问题提出一种变异量子粒子群算法,该算法首先把非线性方程组的求解转化为约束优化问题,然后根据可行性规则,引入约束违反度函数,结合变异算子,不断地寻找更优可行解,逐渐达到搜索全局最优解。数值实验表明,所设计变异量子粒子群算法是可行的、有效的,是求解非线性组的一种成功算法。  相似文献   

10.
粒子群优化算法求解旅行商问题   总被引:92,自引:2,他引:90  
首先介绍粒子群优化的搜索策略与基本算法, 然后通过引入交换子和交换序的概念, 构造一种特殊的粒子群优化算法, 并用于求解旅行商问题. 实验表明了在求解组合优化问题中的有效性.  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.
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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