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1-D Directional Filter Based Texture Descriptor in Fractional Fourier Domain

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Journal of Harbin Institute of Technology(New Series) 2015年第5期22卷 125-128页

作者： Kai tian hongzhang Jin Liying Zheng College of Automation Harbin Engineering University College of Computer Science and Technology Harbin Engineering University

Texture analysis is a fundamental field in computer vision. However,it is also a particularly difficult problem for no universal mathematical model of real world textures. By extending a new application of the fractional Fourier transform( Fr FT) in the field of texture analysis,this paper proposes an Fr FT-based method for describing textures. Firstly,based on the Radon-Wigner transform,1-D directional Fr FT filters are designed to two types of texture features,i. e.,the coarseness and directionality. Then,the frequencies with maximum and median amplitudes of the Fr FT of the input signal are regarded as the output of the 1-D directional Fr FT filter. Finally,the mean and the standard deviation are used to compose of the feature vector. Compared to the WD-based method,three benefits can be achieved with the proposed Fr FT-based method,i. e.,less memory size,lower computational load,and less disturbed by the cross-terms. The proposed method has been tested on16 standard texture images. The experimental results show that the proposed method is superior to the popular Gabor filtering-based method.

关键词： fractional Fourier transform texture analysis Radon-Wigner transform 1-D directional window

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Ghrelin与内分泌代谢异常

生理科学进展 2008年第2期39卷 159-161页

作者：张琳洪天配北京大学第三医院内分泌科北京100083

Ghrelin是近年来新发现的一种小分子活性肽,主要由胃底的X/A样细胞分泌,是生长激素促分泌物受体(GHS-R)的内源性配体。Ghrelin及其受体也可表达于肠道、胰腺、肾脏、性腺、胎盘、甲状腺、肾上腺、下丘脑、垂体等多种内分泌组织或器官。... 详细信息

Ghrelin是近年来新发现的一种小分子活性肽,主要由胃底的X/A样细胞分泌,是生长激素促分泌物受体(GHS-R)的内源性配体。Ghrelin及其受体也可表达于肠道、胰腺、肾脏、性腺、胎盘、甲状腺、肾上腺、下丘脑、垂体等多种内分泌组织或器官。研究表明,ghrelin与糖代谢、甲状腺疾病、肥胖、多囊卵巢综合征等多种内分泌代谢疾患有关。本文将就ghrelin与内分泌代谢异常的关系的研究进展作简要介绍。

关键词： Ghrelin 胰岛素甲状腺肥胖多囊卵巢综合征

Analysis of status quo and research progress in nursing of postpartum fatigue: a literature review

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Frontiers of Nursing 2020年第1期7卷 71-76页

作者： tian-tian Gai Meng-Xi Gao Wei Fan Yan Wang Graduate School Tianjin University of Traditional Chinese MedicineTianjin 300000China chool of Nursing Tianjin University of Traditional Chinese MedicineTianjin 300000China

Postpartum fatigue is an important issue that threatens women’s *** incidence of postpartum fatigue is *** to intervene in time may lead to adverse outcomes such as postpartum depression,premature termination of breastfeeding,child abuse,and low infant *** article reviews the concepts,characteristics,related factors,adverse effects,and interventions of postpartum *** aim is to improve doctors’and nurses’awareness of on postpartum fatigue in pregnant women,enrich the research content and methods,stimulate the interest of nurses,and actively carry out targeted intervention research to prevent or reduce the occurrence of adverse outcomes.

关键词： postpartum fatigue maternal postnatal pregnancy nursing current status research progress

Tellurium intervened Fe-N codoped carbon for improved oxygen reduction reaction and high-performance Zn-air batteries

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Journal of Materials Science & Technology 2023年第6期137卷 215-222页

作者： Rui Wang Zihan Meng Xuemin Yan tian tian Ming Lei Rami Adel Pashameah Hala MAbo-Dief Hassan Algadi Nina Huang Zhanhu Guo Haolin Tang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan 528200China College of Chemistry and Environmental Engineering Yangtze UniversityJingzhou 434023China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Chemistry Faculty of Applied ScienceUmm Al-Qura UniversityMakkah 24230Saudi Arabia Department of Science and Technology University College-RanyahTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Electrical Engineering Faculty of EngineeringNajran UniversityP.O.Box 1988Najran 11001Saudi Arabia College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Chemical and Bimolecular Engineering Integrated Composites Laboratory(ICL)University of TennesseeKnoxvilleTN 37996USA Guangdong Hydrogen Energy Institute of WHUT Xianhu Hydrogen ValleyFoshan 528200China

Pyrolysis-acquired iron and nitrogen codoped carbon(Fe-N-C)has been comprehensively investigated for its promising oxygen reduction reaction(ORR)catalytic performance and structural *** modification of non-metal elements with larger atomic radius and the corresponding intrinsic microstructure-property relations are rarely *** this study,tellurium(Te)intervened Fe-N-C was prepared by micelles-induced polymerization with Te nanowires as an in-situ intervening *** out-plane bonding of Te with Fe induced the increase of both N content and proportion of pyridinic N on the material surface,thus improving the ORR catalytic *** assembled Zn-air battery demonstrated a maximum power density of 250 mW/cm^(2)and excellent rate capability under various discharge current densities,which was much better than the Pt/***,the current work demonstrates a novel Te/Fe-N-C material and reveals an original Te intervened Fe-N-C strategy and N reconfiguration mechanism,which is of great significance for the design of key materials in energy-related fields.

关键词： Te/Fe-N-C Assembly ORR Electrocatalysis Zn-air battery

Assaying poly(ADP-ribose) polymerase activity in plants by polarographic method

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Chinese Science Bulletin 1999年第20期44卷 1883-1887页

作者： Ruihua tian Depu Chen Yaoren Dai Tsing Hua Univ Dept Biol Beijing 100084 Peoples R China Tsing Hua Univ Dept Chem Beijing 100084 Peoples R China

A new method has been developed to assay poly(ADP-ribose) polymerase (PARP) activity in plant tissues through determining the content of nicotinamide (NIC) produced by enzymatic reaction by linear sweeping polarographic method. The detection limit of NIC was 0.03μmol/L, the calibration graph was linear up to 5μmol/L ( r = 0.999). The recoveries were approximately in the range of 92% to 98% and the relative standard deviations were less

关键词： linear sweeping polarographic method NAD+ nicotinamide nuclei poly( ADP-ribose) polymerase (PARP).

短期、中期、长期健康状况代际传递及其城乡异质性研究

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中华疾病控制杂志 2022年第2期26卷 162-168页

作者：和红谈甜中国人民大学人口与发展研究中心中国人民大学北京社会建设研究院中国人民大学健康科学研究所中国人民大学社会与人口学院社会医学教研室北京100872

目的探究中国居民健康状况的代际传递,并分析其城乡异质性。方法基于中国健康与营养调查(China Health and Nutrition Survey,CHNS)数据,通过二分类Logistic回归分析模型、多元线性回归分析模型及交互作用模型,分析短期、中期、长期健... 详细信息

目的探究中国居民健康状况的代际传递,并分析其城乡异质性。方法基于中国健康与营养调查(China Health and Nutrition Survey,CHNS)数据,通过二分类Logistic回归分析模型、多元线性回归分析模型及交互作用模型,分析短期、中期、长期健康状况的代际传递及城乡调节作用。结果母亲、父亲的短期、中期、长期健康状况对子代相应的健康状况有重要影响(母亲-子代:OR_(短期)=5.649,β_(中期)=0.305,OR_(长期)=3.719;父亲-子代:OR_(短期)=3.436,β_(中期)=0.388,OR_(长期)=3.483);城乡调节了母亲-子代健康状况的代际传递(P_(短期)=0.023,P_(中期)=0.038,P_(长期)=0.072),居住于城市地区能弱化母亲-子代间的健康传递。结论亲代短期、中期及长期健康对子代相应健康状况影响密切,建议以家庭为单位开展健康促进工作,遏制不良健康状况代际传递。

关键词：健康状况代际传递城乡

欧洲批判的安全研究:理论探索、研究纲领及其欧洲特性

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中国人民大学学报 2014年第6期28卷 30-37页

作者：罗天虹中国人民大学国际关系学院

对传统安全研究的批评早在冷战后期的20世纪80年代渐成规模。欧洲与美国学者在讨论传统安全概念弊端的初期各有建树,但至90年代末期,大西洋两岸安全研究的分野越来越明显。批判的安全研究在欧洲的发展远比美国强劲有力,并极大地改变了... 详细信息

对传统安全研究的批评早在冷战后期的20世纪80年代渐成规模。欧洲与美国学者在讨论传统安全概念弊端的初期各有建树,但至90年代末期,大西洋两岸安全研究的分野越来越明显。批判的安全研究在欧洲的发展远比美国强劲有力,并极大地改变了欧洲安全研究的面貌,美欧在安全研究的本体论以及纲领研究上变得大不相同。欧洲形成了重塑安全研究的三大中心,即丹麦的哥本哈根、法国的巴黎与英国的阿伯里斯特维斯。以三大分支流派为主干的欧洲批判安全研究,构成了在一个美国人长期把持的领域内颇具欧洲特性的安全理论群。

关键词：欧洲批判的安全研究批判理论欧洲特性

Dynamic adsorption of Xe on a fixed-bed adsorber at 77 K

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Nuclear Science and Techniques 2017年第8期28卷 89-96页

作者： Bin Long Jun-Li Li Qun-Shu Wang Shu-Juan Feng Guo-Qing Zhou tian-Cheng Feng Yan-Jie tian Huai-Cheng Ma Key Laboratory of Particle and Radiation Imaging of Ministry of Education Department of Engineering PhysicsTsinghua University Beijing 100084 China Northwest Institute of Nuclear Technology Xi'an 710024China

In designing a fixed-bed adsorber, it is vital to understand dynamic adsorption properties of the unit. Temperature is an important effect on adsorbent performance, as the dynamic adsorption coefficients tend to increase with decreasing temperature. To minimize the volume of the fixed-bed adsorber, the dynamic adsorption characteristics of Xe were studied at 77 K by employing a variety of adsorbents under different operational conditions. The carbon molecular sieve performed better than that of activated carbon. Both operational conditions and the presence of gaseous impurities were found to affect the adsorption properties.

关键词：固定床吸附器动态吸附性能动态吸附特性操作条件吸附系数碳分子筛 TEM 吸附量

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XML数据库融合中心带宽扩维感知算法

科技通报 2015年第8期31卷 153-155页

作者：田鸿重庆人文科技学院重庆401524

传统方法中,对XML数据库的融合中心带宽扩维算法采用谱估计方法,当融合中心出现了大量以海量数据为基础的信息服务数据时,后续访问需在多个服务器中遍历许多节点,影响访问效率。提出一种基于节点分裂日志的XML数据库融合中心带宽扩维感... 详细信息

传统方法中,对XML数据库的融合中心带宽扩维算法采用谱估计方法,当融合中心出现了大量以海量数据为基础的信息服务数据时,后续访问需在多个服务器中遍历许多节点,影响访问效率。提出一种基于节点分裂日志的XML数据库融合中心带宽扩维感知算法。首先构建XML数据库相对状态系统模型与数据融合算法,设计节点分裂日志的数据融合结构,通过预获取有限的带宽中心信息,推导出实体关联知识库,利用表征关联知识有效指导XML数据库的资源融合和重整,构建实体模型,提高数据融合中心的聚类能力。仿真实验结果表明,该法能有效提高XML数据库融合中心宽带扩维匹配率,执行效率和数据聚类效率提高,展示其优越的应用价值。

关键词： XLM数据库数据融合信息感知