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1.
Most parallel efficient global optimization (EGO) algorithms focus only on the parallel architectures for producing multiple updating points, but give few attention to the balance between the global search (i.e., sampling in different areas of the search space) and local search (i.e., sampling more intensely in one promising area of the search space) of the updating points. In this study, a novel approach is proposed to apply this idea to further accelerate the search of parallel EGO algorithms. In each cycle of the proposed algorithm, all local maxima of expected improvement (EI) function are identified by a multi-modal optimization algorithm. Then the local EI maxima with value greater than a threshold are selected and candidates are sampled around these selected EI maxima. The results of numerical experiments show that, although the proposed parallel EGO algorithm needs more evaluations to find the optimum compared to the standard EGO algorithm, it is able to reduce the optimization cycles. Moreover, the proposed parallel EGO algorithm gains better results in terms of both number of cycles and evaluations compared to a state-of-the-art parallel EGO algorithm over six test problems. 相似文献
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Yue Hangbo Xu Chao Yao Jiachang He Ming Yin Guoqiang Cui Yingde Yang Chufen Guo Jianwei 《Cellulose (London, England)》2022,29(10):5869-5881
Cellulose - The development of plant adhesive with good bonding strength, water resistance and thermal stability remains challenging to replace formaldehyde-based adhesive resins that usually... 相似文献
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根据能量原理,引入大挠度Von-Karman方程,求解了应力不连续简支板的屈曲问题,得到了临界载荷和临界应力计算系数. 相似文献
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Chengye Yuan Jiachang Yao Shusen Li 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):21-27
Abstract For the evaluation of the structural effect of electrophiles on the regioselectivity of ambident anions, the reaction of phosphoryl allylic carbanion with p-substituted benzaldehydes was investigated. 相似文献
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Several cubature formulas on the cubic domains are derived using the dis-crete Fourier analysis associated with lattice tiling, as developed in [10]. The main results consist of a new derivation of the Gaussian type cubature for the product Cheby-shev weight functions and associated interpolation polynomials on [-1,1]2, as well as new results on [-1,1]3. In particular, compact formulas for the fundamental interpo-lation polynomials are derived, based on n3/4 + (n2) nodes of a cubature formula on [-1,1]3. 相似文献
6.
Yilong Gao Jianxiang Wu Wei Zhang Yueyue Tan Jing Gao Jiachang Zhao Bohejin Tang 《Journal of Solid State Electrochemistry》2014,18(11):3203-3207
Zeolitic imidazolate framework-8 (ZIF-8) is synthesized by typical solvothermal method and subsequently calcined under air and nitrogen atmosphere, respectively. The carbon in the calcined ZIF-8 under nitrogen atmosphere was from the carbonization of the guest molecules, without adding any other carbon sources. The samples are characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and electrochemical analyzer system. When the ZIF-8 is used as electrode materials for a supercapacitor in 6 M KOH electrolyte, it displays a pseudocapacitive behavior. The untreated ZIF-8 and calcined ZIF-8 under air and nitrogen atmosphere electrodes exhibit a specific capacitance of 96, 156, and 185 F g?1, respectively, at a scan rate of 5 mV s?1 and good stability over 1,500 cycles. These results indicate that the ZIF-8 is a promising material for supercapacitors. 相似文献
7.
利用Rivlin和Shapiro提出的符号理论,证明了文献[10]中提出的第一类双变量Chebyshev多项式恰为所谓的Steiner区域上具有特殊首项的最小零偏差多项式,并由此导出了几类具有一定代数精度的数值积分公式. 相似文献
8.
Solving large scale linear systems efficiently plays an important role in a petroleum reservoir simulator, and the key part is how to choose an effective parallel preconditioner. Properly choosing a good preconditioner has been beyond the pure algebraic field. An integrated preconditioner should include such components as physical background, characteristics of PDE mathematical model, nonlinear solving method, linear 相似文献
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Gong J Vaidyanathan VG Yu X Kensler TW Peterson LA Sturla SJ 《Journal of the American Chemical Society》2007,129(7):2101-2111
Acylfulvenes (AFs) are a class of semisynthetic agents with high toxicity toward certain tumor cells, and for one analogue, hydroxymethylacylfulvene (HMAF), clinical trials are in progress. DNA alkylation by AFs, mediated by bioreductive activation, is believed to contribute to cytotoxicity, but the structures and chemical properties of corresponding DNA adducts are unknown. This study provides the first structural characterization of AF-specific DNA adducts. In the presence of a reductive enzyme, alkenal/one oxidoreductase (AOR), AF selectively alkylates dAdo and dGuo in reactions with a monomeric nucleoside, as well as in reactions with naked or cellular DNA, with 3-alkyl-dAdo as the apparently most abundant AF-DNA adduct. Characterization of this adduct was facilitated by independent chemical synthesis of the corresponding 3-alkyl-Ade adduct. In addition, in naked or cellular DNA, evidence was obtained for the formation of an additional type of adduct resulting from direct conjugate addition of Ade to AF followed by hydrolytic cyclopropane ring-opening, indicating the potential for a competing reaction pathway involving direct DNA alkylation. The major AF-dAdo and AF-dGuo adducts are unstable under physiologically relevant conditions and depurinate to release an alkylated nucleobase in a process that has a half-life of 8.5 h for 3-alkyladenine and less than approximately 2 h for dGuo adducts. DNA alkylation further leads to single-stranded DNA cleavage, occurring exclusively at dGuo and dAdo sites, in a nonsequence-specific manner. In AF-treated cells that were transfected with either AOR or control vectors, the DNA adducts identified match those from in vitro studies. Moreover, a positive correlation was observed between DNA adduct levels and cell sensitivity to AF. The potential contributing roles of AOR-mediated bioactivation and adduct stability to the cytotoxicity of AF are discussed. 相似文献