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Impact of exergaming on young children's school day energy expenditure and moderate-to-vigorous physical activity levels

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Journal of Sport and Health Science 2017年第1期6卷 11-16页

作者： Zan Gao Zachary Pope Jung Eun Lee David Stodden Nida Roncesvalles Denis Pasco charles c.huang Du Feng School of Kinesiology The University of MinnesotaMinneapolisMN 55455USA Department of Applied Human Science The University of MinnesotaDuluthMN 55812USA Department of Physical Education and Athletic Training University of South CarolinaColumbiaSC 29201USA Department of Kinesiology and Sport Management Texas Tech UniversityLubbockTX 79409USA School of Education The University of Bourgogne Franche-ComtéBesançon 25000France School or Exercise and Sports Science Wayland Baptist UniversityPlainviewTX 79072USA School of Nursing University of NevadaLas VegasNV 89154USA

Background: Although emerging research is demonstrating the potential health impact of exergaming,investigations have primarily been conducted in laboratory settings among small samples with short-term *** on the effectiveness of exergaming in underserved children's objective physical activity(PA) in population-based settings is also ***,most empirical studies have only included 1 type of exergame in the ***,this study's purpose was to investigate the long-term impact of a multigame exergaming intervention among underserved children integrated within school ***,this study examined the effect of exergaming on children's accelerometer-determined sedentary behavior(SB),light PA,moderate-to-vigorous PA(MVPA),and energy expenditure(EE) over 2 years as compared with regular physical education(PE) ***: A total of 261 second-and third-grade children(134 girls,127 boys; mean age 8.27 years) were recruited from 2 Texas elementary ***'s pre-test 3-day SB,light PA,MVPA,and EE at school were assessed in the fall of *** were assigned to 1 of 2groups:(1) exergaming/PE group(125 min weekly of exergaming-based PA program) and (2) comparison group(125 min weekly of PE).PA(SB,light PA,and MVPA) and EE outcome variables were assessed again in 2013(post-test) and 2014(follow-up).Results: Significant time effects were observed for SB(F(1,162)=25.0,p0.05,η~2= 0.004).Subsequent pairwise comparisons revealed significant increases from pre-to post-test for light PA(pchanges in SB(p>0.05).conversely,significant decreases occurred in light PA(pces seen in MVPA(p=0.08) and EE(p=0.06) over the same time period.A significant increase was seen,however,for SB from post-te

关键词： Active video games childhood obesity Light physical activity Moderate-to-vigorous physical activity Physical education Sedentary behavior

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基于DSpace的Lib2.0

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大学图书馆学报 2006年第3期24卷 2-5页

作者：叶鹰黄晨浙江大学杭州310028

指出用户互动是Web2.0和Lib2.0的典型特征,提出以开源软件系统DSpace作为数字图书馆核心引擎的Lib2.0模型。综合资源、技术和服务管理讨论了基于DSpace构建Lib2.0的技术可能性和应用优越性,并论及与Lib2.0相应的Librarian2.0。

关键词： DSpace Lib 2.0 图书馆2.0 图书馆员2.0 数字图书馆

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Measuring academic contributions via keyword analytics

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Journal of Library Science in china 2019年 186-187页

作者： charles c.huang Star X.ZHAO BIAN Yangyi Ronda J.ZHANG Helena H.ZHANG Fred Y.YE 不详

As a tool of logical thinking and derivation,the basic element of language is the *** words reflect concepts,and core concepts construct knowledge,while knowledge evolution contributes to academic *** on the theoretical foundation that keywords in the academic literature characterize concepts,this work attempts to get beyond traditional citation analysis and introduce a framework of academic contribution analysis based on keywords.

关键词： Measuring academic contributions

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测量学术贡献的关键词分析法探析

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中国图书馆学报 2019年第6期45卷 84-99页

作者：黄晨赵星卞杨奕张家榕张慧叶鹰浙江大学图书馆华东师范大学信息管理系南京大学信息管理学院

语言作为逻辑思维和推理工具,其基本要素是语词。重要语词映射成概念,核心概念建构知识,而知识演进促成学术发展。本文以学术文献中的关键词作为概念演化基础,尝试超越传统引文分析法探讨测量学术贡献的关键词分析法。研究发现以一个学... 详细信息

语言作为逻辑思维和推理工具,其基本要素是语词。重要语词映射成概念,核心概念建构知识,而知识演进促成学术发展。本文以学术文献中的关键词作为概念演化基础,尝试超越传统引文分析法探讨测量学术贡献的关键词分析法。研究发现以一个学科内的关键词向量和关键词流量为基准,可分别定义关键词向量通量谱和累积通量谱的h截断和g截断,构成h核和g核内主流关键词,进而可定义主流率和主流指数,用作测量对主流学术研究之学术贡献的新型学术测评参数。合并cNKI、万方、维普三大中文数据库元数据和WoS、Ei里的中文记录元数据建立了2008—2017年数据支持平台,具体探讨了针对学术团体和学术期刊的中观层面实证案例。本文给出的关键词分析法基础框架重点是挖掘学术主体或客体对主流研究的学术贡献,建议在试用和应用中进一步改良和完善。图5。表5。参考文献23。

关键词：分析法关键词向量关键词流量关键词通量主流率主流指数学术评价

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Mechanism of Primary Frequency Regulation for Battery Hybridization in Hydropower Plant

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cSEE Journal of Power and Energy Systems 2024年第5期10卷 2127-2137页

作者： Yiwen Liao Weijia Yang Zhecheng Wang Yifan huang c.Y.chung State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Department of Electrical Engineering The Hong Kong Polytechnic UniversityHong KongChina

Battery hybridization in hydropower plants is a hydropower flexibility enhancement technology innovation that can potentially expand hydropower’s contributions to the grid,but its fundamental characteristics and influencing mechanisms are still *** this paper,primary frequency regulation(PFR)performance and the mechanism of this new technology are studied.A battery hybridized hydropower plant(BH-HPP)model,based on a field-measured-data-based hydropower plant(HPP)model and a verified battery simplified model,is *** of system stability and dynamics is undertaken for three different battery control strategies by root locus and participation factor *** to conventional HPPs,analysis results theoretically reveal BH-HPP can not only accelerate system regulation rapidity but also effectively enlarge HPP stability region during PFR *** domain simulation verifies the results and further shows synthetic control has better performance among introduced ***,initial design ranges of control parameters considering battery capacity and a renewable energy source scenario case are also *** work could provide theoretical support for flexibility enhancement solutions for hydropower systems.

关键词： Battery hybridization dynamic response hydropower plant primary frequency regulation stability

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Efficiency of the motion amplification device with viscous dampers and its application in high-rise buildings

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Earthquake Engineering and Engineering Vibration 2009年第4期8卷 521-536页

作者： Henry c.huang WSP Asia Ltd.

After nearly a decade of application and investigation, a motion amplification device with viscous dampers for energy dissipation has been recognized as an effective solution to mitigate wind or seismic excitation, especially for stiff structural systems. As a result of compensation of amplified motion, it has been proved that the efficiency of viscous damper largely depends on the motion amplification device configuration, particularly for device stiflhess. In this paper, a ＂scissor-jack＂ type of motion amplification device, called a ＂toggle brace damper＂ system, is studied. It is demonstrated that the efficiency of such a device reflected by its amplification factor is not merely a function of its geometric configuration, but is highly dependent on the support elements＇ stiffness as well, similar to the mechanism of a leverage arm. Accordingly, a mathematical model in terms of complex modulus of the viscous damper with consideration of the support brace＇s stiffness is established. The results indicate that the efficiency of the motion amplification device with viscous dampers significantly depends on the stiffness of the support elements. Other parameters, such as toggle brace configuration and damping values of the viscous damper, are studied and compared. As an application example, numerical analyses are conducted to study the dynamic performance of a 39-story office tower installed with toggle brace dampers constructed on soft soil in a reclaimed area, under a combined effect of the vortex shedding of an adjacent existing 52-story building and earthquakes. The results show that viscous dampers with a motion amplification system using a properly designed toggle brace device proved to be an effective solution to alleviate the external excitations.

关键词： motion amplification device vibration mitigation viscous damper energy dissipation toggle brace damper

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A machine learning-based calibration method for strength simulation of self-piercing riveted joints

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Advances in Manufacturing 2024年第3期12卷 465-483页

作者： Yu-Xiang Ji Li huang Qiu-Ren chen charles K.S.Moy Jing-Yi Zhang Xiao-Ya Hu Jian Wang Guo-Bi Tan Qing Liu Key Laboratory for Light-weight Materials Nanjing Tech UniversityNanjing210009People’s Republic of China Design School Xi’an Jiaotong-Liverpool UniversitySuzhou215123JiangsuPeople’s Republic of China Materials Bigdata and Applications Division Materials Academy JitriSuzhou215131JiangsuPeople’s Republic of China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

This paper presents a new machine learning-based calibration framework for strength simulation models of self-piercing riveted(SPR)*** simulations were conducted through the integrated modeling of SPR joints from process to performance,while physical quasi-static tensile tests were performed on combinations of DP600 high-strength steel and 5754 aluminum alloy sheets under lap-shear loading conditions.A sensitivity study of the critical simulation parameters(e.g.,friction coefficient and scaling factor)was conducted using the controlled variables method and Sobol sensitivity analysis for feature ***,machine-learning-based surrogate models were used to train and accurately represent the mapping between the detailed joint profile and its load-displacement *** of the simulation model is defined as a dual-objective optimization task to minimize errors in key load displacement features between simulations and experiments.A multi-objective genetic algorithm(MOGA)was chosen for *** three combinations of SPR joints illustrated the effectiveness of the proposed framework,and good agreement was achieved between the calibrated models and experiments.

关键词： Machine learning Self-piercing riveting(SPR) Sensitivity analysis Multi-objective optimization

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Microstructure and Internal Friction Behavior of Laser 3D Printed Fe-Based Amorphous composites

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 196-204页

作者： Shuilong huang Qingjun chen Li Ji Kan Wang Guosheng huang School of Material Science and Engineering Nanchang Hangkong UniversityNanchang330063China State Key Laboratory for Marine corrosion and Protection Luoyang Ship Material Research Institute(LSMRI)Qingdao266237China

Laser 3D printing,also known as laser additive manufacturing(LAM),is favored for its ability to form bulk metallic glass(BMG)and its composite materials(BMGcs)with freeform *** this work,two different kinds of Fe_(41)co_(7)cr_(15)Mo_(14)c_(15)B_(6)Y_(2)amorphous coatings(A and B)were prepared by using LAM technology under air-and water-cooled conditions,respectively;meanwhile,to reduce the cracks generated due to the residual thermal stresses,coating c obtained by air-sweep annealing of B with a low energy-density *** morphology and amorphous content and microstructure of the coatings were investigated,the results show many cracks in coating B deposited under water-cooled conditions,and its microstructure shows an amorphous-crystal-nanocrystalline mixed *** was suppressed in coating c,obtained by air-sweep annealing based on coating B,but the amorphous content was reduced from 32.6 to 13.4%.And the hardness and corrosion resistance of the coating will increase with the increase in the amorphous ***,the internal friction behavior of a BMGcs was prepared on the basis of the process of sample c is compared with that of as-cast amorphous *** results show that the low temperature internal friction behavior of BMGcs is affected by the defects produced during printing,and the high temperature internal friction behavior is affected by the precipitated hard phase.

关键词： Laser 3D printing Amorphous coating Microstructure corrosion resistance Internal friction behavior

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Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.huang K.Jiang c.N.Wu H.Peng P.c.hen R.Li H.B.Zhuo c.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

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Hybrid HMX multi-level assembled under the constraint of 2D materials with efficiently reduced sensitivity and optimized thermal stability

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Defence Technology（防务技术） 2024年第9期39卷 123-132页

作者： Xiaomin Song Longjin huang Rufang Peng Qi huang Jinjiang Xu Jie Sun Institute of chemical Materials China Academy of Engineering PhysicsMianyang621900China State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

The interfacial interaction between HMX molecules and coating materials is the key to the safety performance of explosives and has received extensive ***,screening suitable coating agents to enhance the interfacial effect to obtain high-energy and low-sensitivity explosives has long been a major *** this work,HMX-PEI/rGO/g-c_(3)N_(4)(HPrGc)composites were innovatively prepared by a multi-level coating strategy of two-dimensional graphite rGO and g-c_(3)N_(4).The g-c_(3)N_(4) used for desensitization has a richπ-conjugated system and shows outstanding ability in reducing friction *** hierarchical structure of HPrGc formed by electrostatic self-assembly andπ-πstacking can effectively dissipate energy accumulation under heat and mechanical stimulation through structural evolution,thus exhibiting a prominent synergistic desensitization effect on *** results show that rGO/gc_(3)N_(4) coating has no effect on the crystal structure and chemical structure of *** importantly,the perfect combination of g-c_(3)N_(4) and rGO endows HPrGc with enhanced thermal stability and ideal mechanical sensitivity(IS:21 J,FS:216 N).Obviously,the new fabrication of HPrGc enriches the variety of desensitizer materials and helps to deepen the understanding of the interaction between explosives and coatings.

关键词： HMX-PEI/rGO/g-c_(3)N_(4) Electrostatic self-assembly π-πstacking Synergistic desensitization

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