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基于分形理论的土壤氡浓度矿化异常的分析方法:以湖南郴州金狮岭地区为例

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南华大学学报（自然科学版） 2018年第4期32卷 15-19页

作者：郭岳岳谭凯旋谭婉玉韩世礼谢焱石吴文博蔡秋娥南华大学核资源工程学院湖南衡阳421001 南华大学数理学院湖南衡阳421001

土壤氡浓度分布具有双分形特征,其分维值分别为D1=0.079 4和D2=1.4654,分形临界值为2 167.7 Bq/m^3.低于临界值的分形其分维值D1很小,代表了区域背景分布,其背景值为1 088.16 Bq/m^3.高于临界值的分形其分维值D2显著增大,反映该区发生... 详细信息

土壤氡浓度分布具有双分形特征,其分维值分别为D1=0.079 4和D2=1.4654,分形临界值为2 167.7 Bq/m^3.低于临界值的分形其分维值D1很小,代表了区域背景分布,其背景值为1 088.16 Bq/m^3.高于临界值的分形其分维值D2显著增大,反映该区发生了较强的成矿作用的叠加.分形临界值可以作为异常下限值.金狮岭地区土壤氡浓度异常区分布范围较大,表明具有较好的成矿远景.

关键词：土壤氡浓度分形异常分析铀

Target detection method for moving cows based on background subtraction

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International Journal of Agricultural and Biological Engineering 2015年第1期8卷 42-49页

作者： Zhao kaixuan He Dongjian College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100ShaanxiChina

Target detection is the fundamental work for perceiving the behavior of cows using video analysis *** videos captured in farming scenes often suffer from a complex background,which leads to difficulty in detecting the target and inconvenience in the subsequent images *** this study,a method was proposed to detect the moving target accurately for cows based on background ***,the bounding rectangle of cows was calculated using the frames difference method to extract the local background in frames,which were averaged and spliced into one image as the entire background ***,the size and location of a cow’s body were determined by the bounding rectangle of cows,and the body area was tracked through the video by the binary ***,the summation coefficients on RGB channels were adjusted to improve the contrast between the target and background ***,taking the body area in every frame as reference area,the performance of target detection was evaluated by the reference area to determine the optimal summation coefficients on RGB channels,and then background subtraction was processed again to finish the detection.A total of 129 videos were used to test the detection algorithm,and the accuracy of the algorithm was 88.34%,which was 24.85%higher than the classical background subtraction *** study shows that the algorithm proposed in this study is feasible to detect the target accurately and timely when cows are walking straight in the farming environment under natural light,and this method can improve the detection performance and is an extension to the classical background subtraction method.

关键词： moving cows target detection background subtraction image analysis target tracking video analysis

Proximal Femur Bionic Nail (PFBN): A Panacea for Unstable Intertrochanteric Femur Fracture

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Engineering 2024年第6期37卷 152-158页

作者： kaixuan Zhang Wei Chen Yingze Zhang School of Medicine Nankai UniversityTianjin 300071China Department of Orthopedic Surgery of Hebei Province The Third Hospital of Hebei Medical UniversityShijiazhuang 050051China Key Laboratory of Biomechanics of Hebei Province Orthopaedic Research Institute of Hebei ProvinceShijiazhuang 050051China National Health Commission(NHC)Key Laboratory of Intelligent Orthopeadic Equipment The Third Hospital of Hebei Medical UniversityShijiazhuang 050051China Chinese Academy of Engineering Beijing 100088China

With the aging population,intertrochanteric femur fracture in the elderly has become one of the most serious public health issues and a hot topic of research in trauma *** to the limitations of internal fixation techniques and the insufficient mechanical design of nails,the occurrence of complications delays patient recovery after surgical *** of a proximal femur bionic nail(PFBN)based on Zhang’s N triangle theory provides triangular supporting fixation,which dramatically decreases the occurrence of complications and has been widely used for clinical treatment of unstable intertrochanteric femur fracture *** this work,we developed an equivalent biomechanical model to analyze improvement in bone remodeling of unstable intertrochanteric femur fracture through PFBN *** results show that compared with proximal femoral nail antirotation(PFNA)and Intertan,PFBN can dramatically decrease the maximum strain in the proximal *** on Frost’s mechanostat theory,the local mechanical environment in the proximal femur can be regulated into the medium overload region by using a PFBN,which may render the proximal femur in a state of physiological overload,favoring post-operative recovery of intertrochanteric femur fracture in the *** work shows that PFBN may constitute a panacea for unstable intertrochanteric femur fracture and provides insights into improving methods of internal fixation.

关键词： Intertrochanteric femur fracture Internal fixation Proximal femur bionic nail(PFBN) Biomechanics Bone remodeling

面向签派放行的航空公司航班放行品质评价指标研究

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成都航空职业技术学院学报 2020年第4期36卷 79-83,88页

作者：王帅翔褚双磊张文涛冯嘉蓬谭凯旋梅丽君王泽宇中国民航大学天津300300 天津市空管运行规划与安全技术重点实验室天津300300

航班放行品质是航空公司签派放行工作的重要因素,提高航班放行品质有利于增强航空公司市场竞争力,节约运营成本。在从签派员能力、工作绩效考核、签派员工作负荷、签派员人为差错、航空公司安全绩效五个方面分析国内外航空公司航班放行... 详细信息

航班放行品质是航空公司签派放行工作的重要因素,提高航班放行品质有利于增强航空公司市场竞争力,节约运营成本。在从签派员能力、工作绩效考核、签派员工作负荷、签派员人为差错、航空公司安全绩效五个方面分析国内外航空公司航班放行品质研究的基础上,建立航班放行品质指标体系,利用层次分析法进行了权重计算,为提升航班放行品质提供了理论依据。

关键词：航班放行品质签派放行指标

Towards storable and durable Zn-MnO_(2) batteries with hydrous tetraglyme electrolyte

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Journal of Energy Chemistry 2023年第5期80卷 432-441,I0010页

作者： kaixuan Ma Gongzheng Yang Chengxin Wang State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and EngineeringSun Yat-sen(Zhongshan)UniversityGuangzhou 510275GuangdongChina

Aqueous rechargeable zinc-based batteries have attracted increasing interest and been considered potential alternatives for state-of-the-art lithium-ion batteries because of the low cost and high *** cathode materials have been gradually developed and demonstrated excellent electrochemical ***,the complex electrochemistry,inevitable hydrogen release,and zinc corrosion severely hinder the practical *** most concerned Zn-MnO_(2)batteries still suffer from the Mn dissolution and formation of *** adding organic solvents to inhibit the activity of water molecules,the hydrous organic electrolytes provide a sound solution for eliminating the unfavorable *** we report a tetraethylene glycol dimethyl ether-based hydrous organic electrolyte consisting of LiClO_(4)·3H_(2)O and Zn(ClO4)2·6H2O,and a birnessite-type MnO_(2)cathode material for Zn-MnO_(2)*** Li+/Zn2+ions co-(de)insertion mechanism is ascertained by the structural and morphological *** electrostatic interaction between inserted ions and crystal structure is reduced effectively by employment of monovalent Li+ions,which ensures structural stability of cathode *** tetraglyme electrolyte inhibits the activity of water molecules and thus avoids the formation of byproduct Zn_(4)ClO_(4)(OH)7·Meanwhile,highly stable Zn plating/stripping for over 1500 h,an average coulombic efficiency of>99%in long-term cycling,and ultralong storage life(the cells can work well after stored over 1 year)are simultaneously realized in the novel *** from these aspects,the Zn-MnO_(2)batteries manifest high specific capacity of 132 mA h g^(-1),an operating voltage of 1.25 V,and a capacity retention of>98%after 1000 cycles at a current density of 200 mA g^(-1).

关键词： Energy storage Zn battery δ-MnO_(2) Hydrous tetraglyme electrolytes Long life

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花岗岩氡析出的混沌特征

南华大学学报（自然科学版） 2022年第2期36卷 1-6,56页

作者：张明华谢焱石龙淑琴吴鹏黄文凯谭凯旋单健南华大学资源环境与安全工程学院湖南衡阳421001 稀有金属矿产开发与废物地质处置技术湖南省重点实验室湖南衡阳421001

相对富铀的花岗岩广泛存在于地表和地下人居环境,其析出的氡会对人体健康造成辐射危害,深入研究花岗岩氡析出机理可为氡防护提供理论依据。本文基于分形和混沌理论,对采自湖南衡阳衡山岩体和广西灌阳都庞岭岩体的样品开展花岗岩氡析出... 详细信息

相对富铀的花岗岩广泛存在于地表和地下人居环境,其析出的氡会对人体健康造成辐射危害,深入研究花岗岩氡析出机理可为氡防护提供理论依据。本文基于分形和混沌理论,对采自湖南衡阳衡山岩体和广西灌阳都庞岭岩体的样品开展花岗岩氡析出通量随时间变化的规律研究,计算了氡浓度时间序列数据的最大Lyapunov指数和混沌吸引子关联维数,并综合分析讨论了环境因素不变条件下花岗岩氡析出的主要影响因素。结果表明,来自衡山岩体和都庞岭岩体的两个样品264组氡浓度时间序列数据的最大Lyapunov指数分别为0.077和0.308,都大于0,证实来自两个不同岩体的花岗岩氡析出随时间的演化过程为复杂的混沌动力学过程,二者的混沌吸引子的分形维数分别为4.714和5.675,反映前者的岩石特征的复杂性要小于后者。控制或描述环境因素不变条件下花岗岩氡析出演化过程的独立变量至少需7个,一方面包括岩石铀含量、镭活度等化学组成,含铀矿物及造岩矿物组成以及铀镭在这些矿物中的赋存形式等原生岩石特征;另一方面是岩石风化和蚀变过程可改变矿物粒度分布、岩石孔隙度、孔径分布、微裂隙的发育程度以及间隙的粗糙度等岩石结构特征。

关键词：花岗岩氡析出 Lyapunov指数混沌吸引子

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Assistive Technology Based on Robotics and Rise in China

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中国康复医学杂志 2013年第6期28卷 511-516页

作者： ZHANG Xiaoyu WANG kaixuan National Research Centre for Rehabilitation Technical Aids Beijing China100176 Institute of Biomechanics and Rehabilitation En- gineering University of Shanghai for Science and Technology Shanghai China200093

The concept of assistive technology based on robotics,rehabilitation robot and intelligent assistive devices. Domestic intelligence assistive devices include intelligent prosthetics, intelligent orthotics, intelligent walker, assistive devices for smart home environment control, intelligent life assistive devices; Domestic intelligent rehabilitation robot include upper limb rehabilitation robot, hand rehabilitation robot, lower limb rehabilitation robot, robotic smart wheelchair, intelligent nursing bed, daily care robot,the development trend of intelligent assistive devices and rehabilitation robot.

关键词：医疗康复美国医疗卫生行业患者护理

Visualization of oxygen vacancies in nanomaterials

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Science China Materials 2024年第11期67卷 3753-3754页

作者： Wenchao Bi kaixuan Wang Guozhong Cao Department of Physics College of ScienceUniversity of Shanghai for Science and TechnologyShanghai 200093China Departments of Materials Science and Engineering and Chemical Engineering University of WashingtonSeattleWA 98195-2120USA

Oxygen vacancies are one of the most common *** are imperfections in the regular geometrical arrangement of the atoms in crystalline *** are point defects,linear defects,plane defects and volume defects in *** an elemental crystal,point defects are formed when atoms are removed from the position that should be filled in the crystal,creating vacancies,or when atoms occupy interstitial sites where no atom would ordinarily appear,causing interstitialcy[1].

关键词： crystal removed arrangement

Estimation of surface geometry on combustion characteristics of AP/HTPB propellant under rapid depressurization

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Defence Technology（防务技术） 2024年第3期33卷 546-558页

作者： kaixuan Chen Zhenwei Ye Xiaochun Xue Yonggang Yu School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina School of Science Hangzhou Dianzi UniversityHangzhou 310018ZhejiangChina

The 2D sandwich model serves as a potent tool in exploring the influence of surface geometry on the combustion attributes of Ammonium perchlorate/Hydroxyl-terminated polybutadiene(AP/HTPB)propellant under rapid pressure *** thickness of the sandwich propellant is derived from slicing the 3D random particle packing,an approach that enables a more effective examination of the micro-flame *** analysis of the predicted burning characteristics has been performed with experimental *** findings demonstrate a reasonable agreement,thereby validating the precision and soundness of the *** on the typical rapid depressurization environment of solid rocket motor(initial combustion pressure is 3 MPa and the maximum depressurization rate is 1000 MPa/s).A-type(a flatter surface),B-type(AP recesses from the combustion surface),and C-type(AP protrudes from the combustion surface)propellant combustion processes are numerically *** comparison of the evolution of gas-phase flame between 0.1 and 1 ms,it is discerned that the flame strength and form created by the three sandwich models differ significantly at the beginning stage of depressurization,with the flame structures gradually becoming harmonized over *** are drawn by comparison extinction times:the surface geometry plays a pivotal role in the combustion process,with AP protrusion favoring combustion the most.

关键词： AP/HTPB propellant BDP model Rapid pressure decay Burning surface geometry