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Focal distance tabu search

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Science China(Information Sciences) 2021年第5期64卷 5-16页

作者： Fred GlOVER Zhipeng lü Meta-Analytics Inc. School of Computer Science and Technology Huazhong University of Science and Technology

Focal distance tabu search modifies a standard tabu search algorithm for binary optimization by augmenting a periodic diversification step that drives the search away from a current best(or elite) solution until the objective function deteriorates beyond a specified threshold or until attaining a lower bound on the distance from the originating solution. The new augmented algorithm combines the threshold and lower bound approaches by introducing an initial focal distance for the lower bound which is updated when the diversification step is completed. However, rather than terminating the diversification step at the customary completion point, focal distance tabu search(TS) retains the focal distance bound through additional search phases designed to improve the objective function, drawing on a strategy proposed with strategic *** algorithm realizes this strategy by partitioning the variables into two sets which are managed together with an abbreviated tabu search process. An advanced version of the approach drives the search away from a collection of solutions rather than a single originating solution, introducing the concept of a signature solution to guide the search. The method can be employed to augment a variety of other metaheuristic algorithms such as those using threshold procedures, late acceptance hill climbing, iterated local search, breakout local search, GRASP, and path relinking.

关键词： tabu search diversification strategic oscillation adaptive partitioning metaheuristics

Hyperonic neutron stars: reconciliation between nuclear properties and NICER and lIGO/VIRGO results

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Communications in Theoretical Physics 2022年第1期74卷 57-63页

作者： luiz l lopes Centro Federal de Educagao Tecnologica de Minas Gerais Campus VIII CEP 37.022-560Varginha-MG-Brasil

Using an extended version of quantum hadrodynamics,I propose a new microscopic equation of state(EoS)that is able to correctly reproduce the main properties of symmetric nuclear matter at the saturation density,as well as produce massive neutron stars and satisfactory results for the radius and the tidal parameter.I show that this EoS can reproduce at least a 2.00 solar mass neutron star,even when hyperons are *** constraints about the radius of a 2.00 M_(⊙) and the minimum mass that enables a direct Urea effect are also checked.

关键词： neutron star nuclear matter tidal deformability DU process hyperons

Principal Value and Its Applications for One Type of Cauchy–FantappièIntegral and the System of Equations

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Acta Mathematica Sinica,English Series 2022年第9期38卷 1537-1550页

作者： lüPing CHEN School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

It is known that principal value plays vital roles in the study of singular *** this paper,one type of Cauchy–Fantappièintegral with multiple indexes is *** the structure of the kernel is complexity,the Jacobian determinant included in the kernel is expanded for making clearly the expression of the ***,one differential operator is utilized for setting up relations between integrals with higher and usual *** work also concerns the convergent properties of the *** order to study Hadamard principal value and composite formula of this integral,finite and divergent parts will be estimated and *** an application,solvability of the system of integral equations with higher order singularity kernel is discussed.

关键词： Principal value Cauchy–Fantappièintegral piecewise smooth manifold differential operator system of singular integral equation

Gaussian Weighted Trajectory Method Ⅳ： No Rainbow Effect in Practice

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Chinese Journal of Chemical Physics 2009年第2期22卷 210-214页

作者： l. Bonnet Institut des Sciences Moléulaires Université Bordeaux 1 351 Cours de la Libéation 33405 Talence Cedex France

The Gaussian weighted trajectory method （GWTM） is a practical implementation of classical S matrix theory （CSMT） in the random phase approximation, CSMT being the first and simplest semi-classical approach of molecular collisions, developped in the early seventies. Though very close in spirit to the purely classical description, GWTM accounts to some extent for the quantization of the different degrees-of-freedom involved in the processes. While CSMT may give diverging final state distributions, in relation to the rainbow effect of elastic scattering theory, GWTM has never led to such a mathematical catastrophe. The goal of the present note is to explain this finding.

关键词： Gaussian weighted trajectory method Classical S matrix theory Rainbow effect

Effect of bias voltage on microstructure of DC magnetron sputtered Al coatings on uranium

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中国有色金属学会会刊：英文版 2004年第z1期14卷 247-250页

作者： lü Xue-chao Chinese Acad Engn Phys Mianyang 621900 Peoples R China

The effect of different bias voltages on microstructure of Al coatings on uranium was investigated by using scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray stress analyzer, respectively. The results indicate that the microstructure is influenced strongly by bias voltage. At low bias voltages, especially at -100 V, the structure of Al coatings is more densely packed than that at high bias voltages of -300 V and -400 V, where the structure looks like open dentritic. On the whole, the peak (111) orientation is predominant with the increase of bias voltage, but at -400 V, the diffractive intensity of main peaks (111) and (200) is close to the standard reference. The residual stress on Al coatings surface is small, which has a change from tensile to compressive stress with the increase of bias voltage.

关键词： magnetron sputtering deposition bias voltage coatings microstructure uranium

USING THE SKEW-SYMMETRIC ITERATIVE METHODS FOR SOlUTION OF AN INDEFINITE NONSYMMETRIC lINEAR SYSTEMS

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Journal of Computational Mathematics 2014年第3期32卷 266-271页

作者： B.l. Krukier l.A. Krukier Southern Federal University Computer Center Rostov-on-Don Russia

The concept of the field of value to localize the spectrum of the iteration matrices of the skew-symmetric iterative methods is further exploited. Obtained formulas are derived to relate the fields of values of the original matrix and the iteration matrix. This allows us to determine theoretically that indefinite nonsymmetric linear systems can be solved by this class of iterative methods.

关键词： Skew-symmetric iterative methods Indefinite nonsymmetric linear systems.

呋虫胺和唑虫酰胺在茶叶加工过程中的残留特征及膳食风险评估

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食品科学 2025年第1期46卷 192-199页

作者：李春勇吕莹金静王霞秦曙山西农业大学山西功能农产品检验检测中心山西太原030031

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后... 详细信息

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后,经超高效液相色谱-串联质谱法检测,外标法定量。结果表明:在0.005~0.500μg/ml范围内,呋虫胺及其代谢物、唑虫酰胺质量浓度与其响应峰面积呈良好线性关系(R^(2)>0.99),在0.05、1.00、20.00、50.00 mg/kg(茶鲜叶、茶干叶),0.05、0.10、5.00 mg/kg(茶汤)添加水平下,呋虫胺及其代谢物1-甲基-3-[(3-四氢呋喃)甲基]脲、1-甲基-3-[(3-四氢呋喃)甲基]二氢胍盐的平均加标回收率为74%~103%,相对标准偏差为1%~9%;唑虫酰胺的平均加标回收率为75%~95%,相对标准偏差为1%~6%,方法定量限均为0.05 mg/kg;20%呋虫胺·唑虫酰胺微乳剂按推荐剂量施药后,呋虫胺(含代谢物)在茶鲜叶中的规范残留试验中值(supervised trials median residue,STMR)经烘干因子校正后与茶干叶中STMR相应的国家估算每日摄入量(national estimated daily intake,NEDI)均为4.08 mg,占每日允许摄入量(allowable daily intake,ADI)的32.4%;唑虫酰胺在茶鲜叶中的STMR经烘干因子校正后的NEDI为0.17581 mg,占ADI的46.5%,茶干叶中STMR对应的NEDI为0.18925 mg,占ADI的50.1%,呋虫胺和唑虫酰胺在不同评估模型下获得的长期膳食暴露风险均低于100%;呋虫胺(含代谢物)经加工因子校正后的国际短期膳食摄入量(international estimation of short-term dietary intake,IESTI)与校正前处于同一风险水平,低于急性参考剂量(acute reference dose,ARfD)(1 mg/kg);唑虫酰胺的IESTI为3.46×10^(-4) mg/kg(采收间隔7 d),低于ARf D(0.01 mg/kg),本研究方法在茶汤中未检测到唑虫酰胺残留,故未得到浸泡因子及相应的IESTI。综上,按推荐剂量在茶树上使用20%呋虫胺·唑虫酰胺微乳剂是安全的,最终残留量对应的长期及急性膳食摄入风险均在可接受范围,利用加工因子校正评估模型更切合实际风险水平。

关键词：呋虫胺唑虫酰胺茶叶加工因子残留特征风险评估

The effect of social context and social scale on the perception of relationships in monk parakeets

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Current Zoology 2015年第1期61卷 55-69页

作者： Elizabeth A. HOBSON Darlene J. JOHN Tiffany l. MCINTOSH Michael l. avery Timothy F. WRIGHT National Institute for Mathematical and Biological Synthesis University of Tennessee Knoxville TN 37996-3410 USA Department of Biology New Mexico State University Las Cruces NM 88003USA USDA Wildlife Services National Wildlife Research Center Gainesville FL 32641USA

Social relationships formed within a network of interacting group members can have a profound impact on an indi- vidual＇s behavior and fitness. However, we have little understanding of how individuals perceive their relationships and how this perception relates to our external measures of interactions. We investigated the perception of affiliative and agonistic relation- ships at both the dyadic and emergent social levels in two captive groups of monk parakeets （Myiopsitta monachus, n = 21 and 19） using social network analysis and playback experiments. At the dyadic social scale, individuals directed less aggression to- wards their strong affiliative partners and more aggression towards non-partner *** the emergent social scale, there was no association between relationships in different social contexts and an individual＇s dominance rank did not correlate with its popularity rank. Playback response pattems were mainly driven by relationships in affiliative social contexts at the dyadic scale. In both groups, individual responses to playback experiments were significantly affected by strong affiliative relationships at the dyadic social scale, albeit in different directions in the two groups. Response pattems were also affected by affiliative relation- ships at the emergent social scale, but only in one of the two groups. Within affiliative relationships, those at the dyadic social scale were perceived by individuals in both groups, but those at the emergent social scale only affected responses in one group. These results provide preliminary evidence that relationships in affiliative social contexts may be perceived as more important than agonistic relationships in captive monk parakeet groups. Our approach could be used in a wide range of social species and comparative analyses could provide important insight into how individuals perceive relationships across social contexts and social scales [Current Zoology 61 （1）： 55-69, 2015].

关键词： Affiliative Agonistic Dominance Eigenvector centrality Emergent social property Myiopsitta monachus Parrot Popularity Rank Social network analysis

RElIABIlITY ANAlYSIS FOR AN AERO ENGINE TURBINE DISK UNDER lOW CYClE FATIGUE CONDITION

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Acta Metallurgica Sinica(English letters) 2004年第4期17卷 514-520页

作者： C.l.liu Z.Z.lü Y.l.Xu School of Aviation Northwestern Polytechnical University Xi'an 710072 ChinaSchool of Aviation Northwestern Polytechnical University Xi'an 710072 ChinaChina Aviation Research Institute 608 Zhuzhou 412002 China

Reliability analysis methods based on the linear damage accumulation law (lDAl) and load-life interference model are studied in this paper. According to the equal probability rule, the equivalent loads are derived, and the reliability analysis method based on load-life interference model and recurrence formula is constructed. In conjunction with finite element analysis (FEA) program, the reliability of an aero engine turbine disk under low cycle fatigue (lCF) condition has been analyzed. The results show the turbine disk is safety and the above reliability analysis methods are feasible.

关键词： low cycle fatigue life reliability analysis load-life interference model recurrence method aero engine turbine disk