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Learning to select the recombination operator for derivative-free optimization

Science China Mathematics 2024年第6期67卷 1457-1480页

作者： Haotian Zhang jianyong Sun Thomas back Zongben Xu School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049China Leiden Institute of Advanced Computer Science Leiden UniversityLeiden2333 CANetherlands

Extensive studies on selecting recombination operators adaptively,namely,adaptive operator selection(AOS),during the search process of an evolutionary algorithm(EA),have shown that AOS is promising for improving EA's performance.A variety of heuristic mechanisms for AOS have been proposed in recent decades,which usually contain two main components:the feature extraction and the policy setting.The feature extraction refers to as extracting relevant features from the information collected during the search process.The policy setting means to set a strategy(or policy)on how to select an operator from a pool of operators based on the extracted feature.Both components are designed by hand in existing studies,which may not be efficient for adapting optimization problems.In this paper,a generalized framework is proposed for learning the components of AOS for one of the main streams of EAs,namely,differential evolution(DE).In the framework,the feature extraction is parameterized as a deep neural network(DNN),while a Dirichlet distribution is considered to be the policy.A reinforcement learning method,named policy gradient,is used to train the DNN.As case studies,the proposed framework is applied to two DEs including the classic DE and a recently-proposed DE,which result in two new algorithms named PG-DE and PG-MPEDE,respectively.Experiments on the Congress of Evolutionary Computation(CEC)2018 test suite show that the proposed new algorithms perform significantly better than their counterparts.Finally,we prove theoretically that the considered classic methods are the special cases of the proposed framework.

关键词： evolutionary algorithm differential evolution adaptive operator selection reinforcement learning deep learning

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Upcycling end of lithium cobalt oxide batteries to electrocatalyst for oxygen reduction reaction in direct methanol fuel cell via sustainable approach

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journal of Energy Chemistry 2023年第7期82卷 148-157,I0004页

作者： Keyru Serbara Bejigo Kousik Bhunia jungho Kim Chaehyeon Lee Seoin back Sang-jae Kim Nanomaterials&System Lab Major of Mechatronics EngineeringFaculty of Applied Energy SystemJeju National UniversityJeju 63243Republic of Korea Nanomaterials&System Lab Major of Mechanical System EngineeringCollege of EngineeringJeju National UniversityJeju 63243Republic of Korea Research Institute of New Energy Industry(RINEI) Jeju National UniversityJeju 63243Republic of Korea Department of Chemical and Biomolecular Engineering Institute of Emergent MaterialsSogang UniversitySeoul 04107Republic of Korea

Recycling spent lithium-ion batteries(SLIBs)has become essential to preserve the environment and reclaim vital resources for sustainable development.The typical SLIBs recycling concentrated on separating valuable components had limitations,including high energy consumption and complicated separation processes.This work suggests a safe hydrometallurgical process to recover usable metallic cobalt from depleted LiCoO_(2)batteries by utilizing citric acid as leachant and hydrogen peroxide as an oxidizing agent,with ethanol as a selective precipitating agent.The anode graphite was also recovered and converted to graphene oxide(GO).The above components were directly resynthesized to cobaltintegrated nitrogen-doped graphene(Co@NG).The Co@NG showed a decent activity towards oxygen reduction reaction(ORR)with a half-wave potential of 0.880 V vs.RHE,almost similar to Pt/C(0.888 V vs.RHE)and with an onset potential of 0.92 V vs.RHE.The metal-nitrogen-carbon(Co-N-C)having the highest nitrogen content has decreased the barrier for ORR since the reaction was enhanced for Co@NG-800,as confirmed by density functional theory(DFT)simulations.The Co@NG cathode catalyst coupled with commercial Pt-Ru/C as anode catalyst exhibits excellent performance for direct methanol fuel cell(DMFC)with a peak power density of 34.7 mW cm^(-2)at a discharge current density of120 m A cm^(-2)and decent stability,indicating the promising utilization of spent battery materials in DMFC applications.Besides,lithium was recovered from supernatant as lithium carbonate by coprecipitation process.This work avoids sophisticated elemental separation by utilizing SLIBs for other renewable energy applications,lowering the environmental concerns associated with recycling.

关键词： Density functional theory(DFT) Direct methanol fuel cell Leaching Nitrogen doping Oxygen reduction reaction Recycling Spent lithium-ion batteries

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商业教育保险在中国高等教育中的应用研究

商业教育保险在中国高等教育中的应用研究

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作者： back GYEONG RYEONG 哈尔滨工业大学

学位级别：硕士

近年来各国高等教育事业快速发展,并取得丰硕成果。但伴随高校的快速发展,高等教育经费不足的问题日益突出。分析和解决高等教育经费不足的问题,已成为各个国家主要探讨的问题之一。本文将主要针对中国高等教育经费来源中,中产阶级家庭... 详细信息

近年来各国高等教育事业快速发展,并取得丰硕成果。但伴随高校的快速发展,高等教育经费不足的问题日益突出。分析和解决高等教育经费不足的问题,已成为各个国家主要探讨的问题之一。本文将主要针对中国高等教育经费来源中,中产阶级家庭所要承担的教育支出,在解决这一问题上本文调查了英国、澳大利亚、韩国等国家家庭应对高等教育学费方式。发现相对于英国,澳大利亚主要依赖于政府拔款、学费及保障措施、销售和服务收入、开展高等教育国际合作等,韩国采用商业保险解决学费问题具备更高的操作可行性。因此,本文在借鉴韩国商业教育保险的基础上并以两国相似的教育保险产品,通过对中韩两国较为完善的四大保险公司(韩国教保生命,韩国东阳生命,康泰保险公司,平安保险公司)来进行本论文的主要分析,构建指标体系。首先对商业教育保险在中国高等教育学费方面发展的可行性分析,并在此基础上对韩国成功案例进行分析,建立在中国教育背景下应用商业保险所需的指标体系以服务于高等教育商业保险的模式设计。可行性分析采取调查问卷的方式,从供求两个角度进行分析,评估市场对于这类保险产品的需求程度以及从实战角度考察保险公司对于推出这类产品的信心,双向考察商业教育保险在高等教育学费的可行性。在指标体系建立方面,将中韩已有的商业教育保险进行梳理,提炼出在中国推行商业教育保险的指标体系,以完成教育商业保险的适应性分析。其次,对调查问卷部分的数据运用统计分析方法,将收集上来的问卷利用spss软件进行数据分析,并统计投保意愿和投保能力的构成因子。在权重的确定方面,利用了熵权法来界定各个指标的权重。主要从投保人和保险推销者分别探讨了在中国推行高等教育商业保险是否可行,因而,行文路线从发现问题,建立合适的指标体系,到进行调查问卷,调查问卷基本统计结果处理,熵权法分析,投保意愿和投保能力耦合协调度计算并得出从韩国借鉴相关的保险部分内容在中国应用是可行的。本文的创新点主要表现在以下两个方面:首先,试图探究通过商业教育保险来满足学生家庭对高等教育的支出。其次,进一步完善中国商业教育保险保障制度在内的高等教育筹资辅助措施,使它们更加细化。商业教育保险课题是一个不断变化和发展的较新的领域,论文中对一些问题的研究还不够深入,希望在未来的学习和研究中能够深入研究,弥补不足。

关键词：高等教育学费经费来源商业教育保险

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Indian plate paleogeography, subduction and horizontal underthrusting below Tibet: paradoxes, controversies and opportunities

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National Science Review 2022年第8期9卷 175-193页

作者： Douwe j.j.van Hinsbergen Department of Earth Sciences Utrecht University

The India–Asia collision zone is the archetype to calibrate geological responses to continent–continent collision, but hosts a paradox: there is no orogen-wide geological record of oceanic subduction after initial collision around 60–55 Ma, yet thousands of kilometers of post-collisional subduction occurred before the arrival of unsubductable continental lithosphere that currently horizontally underlies Tibet. Kinematically restoring incipient horizontal underthrusting accurately predicts geologically estimated diachronous slab break-off, unlocking the Miocene of Himalaya–Tibet as a natural laboratory for unsubductable lithosphere convergence. Additionally, three endmember paleogeographic scenarios exist with different predictions for the nature of post-collisional subducted lithosphere but each is defended and challenged based on similar data types. This paper attempts at breaking through this impasse by identifying how the three paleogeographic scenarios each challenge paradigms in geodynamics, orogenesis, magmatism or paleogeographic reconstruction and identify opportunities for methodological advances in paleomagnetism, sediment provenance analysis, and seismology to conclusively constrain Greater Indian paleogeography.

关键词： collision orogenesis subduction reconstruction Himalaya Tibet

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The moderating effect of physical activity on the relationship between bullying and mental health among sexual and gender minority youth

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journal of Sport and Health Science 2023年第1期12卷 106-115页

作者： Sally j.Kirklewski Ryan j.Watson Carolyn Lauckner Department of Health Promotion and Behavior University of GeorgiaAthensGA 30602USA Human Development and Family Sciences University of ConnecticutStorrsCT 06269 USA Department of Behavioral Science University of Kentucky College of MedicineUniversity of KentuckyLexingtonKY 40506USA

background:Sexual and gender minority youth frequently experience bullying,which often contributes to higher depressive symptoms and lower self-esteem.Given that physical activity(PA)can mitigate depressive symptoms and improve self-esteem,we examined the moderating effect of PA on the relationship between bullying and mental health among sexual and gender minority youth.Methods:Data from the Lesbian,Gay,Bisexual,Transgender,and Queer National Teen Survey(n=9890)were analyzed.Hierarchical regression analyses examined the influence of history and frequency of being bullied,PA,and the interaction of these variables on depressive symptoms and self-esteem.Simple slopes analyses were used to probe significant interactions.Results:Results indicated the importance of accounting for bullying history when examining effects of PA on mental health.PA was negatively related to depression(t=-4.18,p<0.001)and positively related to self-esteem(t=12.11,p<0.001).Bullying frequency was positively related to depression(t=19.35,p<0.001)and negatively related to self-esteem(t=-12.46,p<0.001).There was a significant interaction between bullying frequency and PA for depression(t=4.45,p<0.001)and self-esteem(t=-4.69,p<0.001).Post hoc analyses suggested that the positive effects of PA on mental health may be limited to those not bullied because it had a negligible effect on those who were bullied.Conclusion:Results suggest that sexual and gender minority youth exercise interventions aiming to improve mental health should first address bullying history;otherwise,their effectiveness may be limited to those who have been bullied.

关键词： Bullying Depression Exercise LGBTQ Self-esteem Youth

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Natural products and drug discovery

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National Science Review 2022年第11期9卷 37-57页

作者： David j.Newman NIH Special Volunteer

This review covers the recent history of a series of very important natural products and their derivatives that are currently in use or under evaluation in the areas of anti-infectives, important cancer treatments that include antibody drug conjugates, followed by a discussion of type 2 diabetes(T2DM) drugs and angiotensin converting enzyme inhibitors. The current structures of the agents are shown, though in the case of some peptides used in T2DM drugs the standard single leTher abbreviation for an amino acid is used.

关键词： artemisinin glycopeptides anthracyclines dolastatin diabetes 2 ACE inhibitors

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Geochemical studies of hybrid granite from Madugulapalli area, Eastern Dharwar Craton, Southern India: Implications for crustal mixing

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Acta Geochimica 2023年第1期42卷 9-23页

作者： Nagamma j Ratnakar j Ajay kumar A Ashok Ch State Mines and Geology Department 508001 NalgondaIndia Department of Geology Osmania University500007 HyderabadIndia CSIR-National Geophysical Research Institute 500007 UppalHyderabadIndia

Magma produced by melting of continental crust and mantle at the Archean-Proterozoic boundary are compositionally variable and chemical compositions provide evidence for the mixing of two sources. Understanding the composition of hybrid magma is essential for determining the comparative infl uence of crust and mantle sources during orogenesis. The hybrid granites are less documented in Indian cratons, especially less in Dharwar Craton. Here we present petrographic and whole-rock geochemical data of Madgulapalli granitic rocks situated in the NE part of the Eastern Dharwar Craton(EDC), to elucidate their petrogenesis and role in crust formation. The Madugulapalli granites(MPG) are composed chiefl y of plagioclase, quartz, and alkali feldspar with associated biotite showing alteration and inter-granular textures. Geochemically, they are metaluminous to peraluminous in nature with calc-alkaline hybrid granite. The hybrid granites exhibit both negative and positive europium anomalies;the lower Rb/Sr, Rb, Sr, and higher Sr/Y,(Dy/Yb)N ratios suggest that the interaction of older rocks with residual garnet source melted at high pressures. We hypothesize that hybrid granites are formed by interaction(e.g., metasomatism, mingling, or mixing) between parental magmas and pre-existing rocks with the infl uence of sanukitoid melts(heat source) in a subduction environment. The genesis of the hybrid granites demonstrates the mixing coupled with diff erentiation in the petrogeny’s residue system in a syn-collision setting followed by continental crust stability in EDC during the Neoarchean period.

关键词： Madugulapalli granite Hybrid granite Crustal mixing Subduction

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孔子学院与世宗学堂的比较研究

孔子学院与世宗学堂的比较研究

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作者：白智善（back jISEON）山东师范大学

学位级别：硕士

本论文是以中国的汉语国际教育与韩国对外韩语教育为中心,对两国本国语言普及政策及办法的研究。希望利用两国的本国语言普及政策和统计资料,比较汉语国际教育的“孔子学院”和对外韩语教育的代表性普及机构“世宗学堂”。从政策层面和... 详细信息

本论文是以中国的汉语国际教育与韩国对外韩语教育为中心,对两国本国语言普及政策及办法的研究。希望利用两国的本国语言普及政策和统计资料,比较汉语国际教育的“孔子学院”和对外韩语教育的代表性普及机构“世宗学堂”。从政策层面和教育层面进行比较分析,了解中国的汉语国际教育和韩国对外韩语教育的成果和问题点。目的是为了持续有效地发展,探索改善方案。进入21世纪时代后,世界各国为向全世界普及本国文化及语言做出了各种努力。中国和韩国也不例外。中国经济增长迅猛,掀起了全世界学习汉语的热潮,韩国因为韩流(韩国文化在亚洲和世界范围内流行的现象影响)文化的输出,世界上学习韩国语的人数大幅增加。本文计划比较研究两国实施的本国语普及政策及教育方式。本研究的构成如下:本文共分为四个章节。第一章提出研究的必要性和目的后,介绍本论文研究的难点和方法。另外,还将分析孔子学院和世宗学堂的论文和研究资料等,掌握目前两个机构以何种方法运营。第二章是以对软实力和公共外交的理论讨论为基础,掌握目前中国和韩国对软实力和公共外交的观点和推进情况。第三章是世宗学堂和孔子学院的比较研究。首先了解了孔子学院和世宗学堂的设立背景、目的、运营现状。在运营现状中,通过图表掌握并整理了孔子学院和世宗学堂在哪个国家集中设立、从设立日开始到现在的增加趋势如何等数据。另外,以教育课程为中心,对教材、教师培养、资格证考试、网站、奖学金制度等运营情况进行了调查。以这样的研究结果为基础,第三节对两个机构的增长趋势、管理层的构成、设立方式、文化外交作用等共同点和差异进行了概括整理。第四章通过前一节得出的结果,分析了孔子学院和世宗学堂的局限性,还提出了两个机构可以克服的局限点和今后发展方向。最后是本文的结语,总结本文的研究过程、结论以及不足之处。

关键词：软实力公共外交孔子学院世宗学堂

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新型冠状病毒肺炎医患沟通手册

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英国医学杂志中文版 2020年第12期23卷 720-720页

作者： Nathan A Gray Anthony L back 李丹麑(译) Department of Medicine Duke University School of MedicineDurhamNorth CarolinaUSA Department of Medicine University of WashingtonSeattleWashingtonUSA 中华医学会学术会务部

以下漫画改编自VitalTalk发布的《医患沟通手册》。漫画完整版可通过以下网址阅览:https://***/content/369/bmj.m2255《医患沟通手册》可通过以下网址阅览:***/guides/covid-19-communicationskills/.来源与同行评议(Provenance and pe... 详细信息

关键词：医患沟通网址同行评议

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Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

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journal of Iron and Steel Research(International) 2022年第5期29卷 819-835页

作者： j.L.Guo T.j.Chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

The effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were investigated.The results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more easily.The softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface layer.These vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing force.It is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is weakened.These behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

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