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Spatiotemporal Differences and Classification Regulation of Urbanization Impact on Agricultural Development in Shrinking Areas:A Case Study of 15 Shrinking Cities in Three Provinces of Northeast China

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Chinese Geographical Science 2023年第6期33卷 1053-1067页

作者： chen xiaohong LIU Haihan AN Yongle DAI Yue PAN Wei WANG Ying TANG We College of Geography Science Harbin Normal UniversityHarbin150025China Harbin Urban and Rural Planning&Design Institute Harbin150010China

Studying the impact of urbanization on agricultural development in shrinking areas is important for maintaining food security and promoted agricultural development in *** on the measurement results of the shrinking cities in the three provinces of Northeast China,this paper selects 15 shrinking cities as the research object,and constructs a multi-dimensional index system to explore the impact of the urbanization level of the shrinking areas on the agricultural development in the region since 2007–2019,analyzes the influencing factors and their differences by using the geographically-weighted regression model and Geodetector,and proposes a targeted regulation *** results show that:1)overall,there is a negative correlation between the urbanization level and the agricultural development level in the contracted areas of the three northeastern *** urbanization level in these areas has a certain negative impact on the overall level of agricultural development;2)regarding the time dimension,the impact of urbanization level on the agricultural development level in the contracted areas of the three northeastern provinces gradually increases over time;3)regarding the spatial pattern,the overall impact of shrinking urbanization levels in the three provinces of Northeast China on the agricultural development shows a significant distribution pattern of high in the east and low in the west;4)the total population and natural population growth rate at the end of the year were the main factors influencing a certain level of urbanization on agricultural development in the shrinking cities while population density and the urban fixed asset investment rate were the secondary factors;and 5)the main reasons why the level of agricultural development in different cities was affected by the level of urbanization were ***,they can be categorized into areas of population loss and spatial construction,which can be further divided into area of population

关键词： urbanization agricultural development classification and regulation shrinking cities three provinces of Northeast China

Short Term Prediction of Freeway Exiting Volume Based on SVM and KNN

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International Journal of Transportation Science and Technology 2015年第3期4卷 337-351页

作者： Xiang Wang Kang An Liang Tang xiaohong chen Ph.D.Candidate Key Laboratory of Road and Traffic Engineering of the Ministry of EducationTongji University 4800 Cao’an RoadShanghai201804P.R.of China Graduate Research Assistant Department of Civil and Environmental Engineering Transportation Systems Research Laboratory3109 Jeong H.Kim Engineering BuildingUniversity of MarylandCollege ParkMD 20740 Professor Key Laboratory of Road and Traffic Engineering of the Ministry of EducationTongji University 4800 Cao’an RoadShanghai201804P.R.of China

In order to better predict the traffic states on freeways and make management decisions,a hybrid model of support vector machine(SVM)and K-nearest neighbor(KNN)is proposed for shortterm freeway exiting volume ***,a historical data set is built by using the freeway toll *** abnormal toll records,such as records that have same entry and exit station,illogical time record and abnormal travel speed,are excluded by data quality *** on the historical dataset,it is found that the exiting volume has periodical variation over time which provides the basis of the short-term ***,the historical data set is cross-classified into twelves groups based on the day of week and time of *** prediction has been done for each ***,the prediction is accomplished by the hybrid-model of SVM and *** exiting volumes of previous time periods are used as the feature vector for KNN and ***,a dynamic weight is adopted for the prediction of current time period based on the latest prediction accuracy of KNN and *** model results indicate that the proposed algorithm is feasible and *** Mean Absolute Percentage Error is under 10%.When comparing with the results of single KNN or SVM method,the results show that the combination of KNN and SVM can improve the reliability of the prediction *** proposed method can be implemented in the on-line application of exiting volume prediction,which is able to consider different vehicle types.

关键词： Freeway Exiting Flow Short-term Prediction KNN SVM Hybrid Model

Synthesis of Carbon Nanotubes using Cu-Cr-O as Catalyst by Chemical Vapor Deposition

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Journal of Wuhan University of Technology(Materials Science) 2014年第5期29卷 928-932页

作者：赵腾腾刘萍 chen xiaohong ZHAO Chunjing LIU Xinkuan LI Wei School of Mechanical Engineering University of Shanghai for Science and Technology School of Materials Science and Engineering University of Shanghai for Science and Technology

A novel powder catalyst Cu-Cr-O applied to the synthesis of carbon nanotubes （CNTs） was developed, which was prepared via ammonia precipitation method. Techniques of thermo-gravimetric/ differential scanning calorimeter （TG-DSC）, X-ray diffraction （XRD） as well as scanning electron microscopy （SEM） and transmission electron microscopy （TEM） have been employed to characterize the thermal decomposition procedure, crystal phase and micro structural morphologies of the as-synthesized materials, respectively. The results show that carbon nanotubes are successfully synthesized using Cu-Cr-O as catalyst when the precursors are calcined at 400, 500, 600, and 700 ℃. The results indicate that the calcination of the Cu-Cr-O catalyst at 600 ℃ is an effective method to get MWCNT with few nano-tube defects or amorphous carbons.

关键词： carbon nanotubes Cu-Cr-O catalyst chemical vapor deposition calcined temperature

Catalytic mechanism of in-situ Ni/C co-incorporation for hydrogen absorption of Mg

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Journal of Magnesium and Alloys 2023年第5期11卷 1815-1824页

作者： Bogu Liu Bao Zhang Haixiang Huang xiaohong chen Yujie Lv Zhongyu Li Jianguang Yuan Ying Wu Central Iron&Steel Research Institute Advanced Technology&Materials Co.LtdNo.76 XueyuannanluHaidian DistrictBeijing 100081China Advanced Materials Research Institute North China Electric Power UniversityNo.2 Beinonglu Changping DistrictBeijing 102206China

Ni and carbon materials exhibit remarkable catalysis for the hydriding reaction of *** the underlying mechanism of Ni/C hybrid catalysis is still *** this work,density functional theory(DFT)calculation is applied to investigate the effect of Ni/C co-incorporation on the hydriding reaction of Mg *** morphology and crystal structure of the Ni/C co-incorporated Mg sample show that the coincorporated structure is *** transition state searching calculation suggests that both the incorporations of Ni and C are beneficial for the H_(2) *** Ni atom has a dramatic improvement for H_(2) dissociation and makes the H diffusion become limiting step of the hyriding *** Ni dz_(2)orbit and H s orbit accept the electrons and combine together compactly,while the Ni d_(xy) orbit is *** catalytic effect of Ni on H_(2) dissociation can be ascribed to the bridging effect of Ni d_(xy) *** incorporation of C can weaken the over-strong interaction between Ni and H which hindered the H diffusion on Mg(0001).The Ni/C co-incorporated Mg(0001)shows the best performance during hyriding reaction compared with the clean and single incorporated Mg(0001).

关键词： Magnesium Ni/C co-incorporation Density functional theory Catalytic effect Hydriding reaction

Strong Limb Tactics of the Boulenger's Lazy Toad,Scutiger boulengeri:Inferred from Limb Muscles

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Asian Herpetological Research 2020年第4期11卷 360-364页

作者： Lixia ZHANG Xiangyu YUAN Yongsun SHENG Fei YU Xueting ZHONG xiaohong chen Dingqi RAO Department of Ecology College of Life SciencesHenan Normal UniversityXinxiang 453007HenanChina Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province College of Life SciencesHuzhou UniversityHuzhou 313000ZhejiangChina State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunming 650223YunnanChina

Theory predicts that well-developed limb musculature can result from sexual selection favoring strong *** tested for this prediction in the Boulenger's lazy toad(Scutiger boulengeri),a species that exhibits inguinal *** expected,we found that males had more massive forelimbs and hindlimbs than those of *** addition,amplectant males had relatively more massive hindlimbs than non-amplectant *** pattern can be explained by sexual selection,as the greater forelimb muscles allow males to hold females more tightly and massive hindlimbs likely confer a locomotor advantage in defending *** study contributes to an increasing body of literature clarifying the role of sexual selection in producing sexual dimorphism in anuran limbs.

关键词： inguinal amplexus limb muscles Scutiger boulengeri sexual dimorphism sexual selection

Comparative Analysis and Fuzzy Selection of Information System Development Approach

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Systems Science and Systems Engineering 1998年第1期8卷 121-129页

作者： chen xiaohong LIU Mai YASUHIKO Takahara College of Business and Management Central South University of TechnologyChangshaHunanP.R.China Department of Management and Systems Engineering China Institute of TechnologyChina275Japan

At the beginning, this paper briefly introduces the evolution of information system development approach (ISDA), which can be divided into five categories: life cycle approach (LCA), structured approach (SA),prototyping approach (PA), object oriented approach (OOA) and soft system methodology (SSM). After we make a comparative analysis of them,the main factors resulting in failure of information system development (ISD) in China are explained in detail. Consequently, such an assertion that false selection of unsuitable ISDA is the most important reason leading to unsuccessful ISD is reached. In order to avoid it, based on the fuzzy decision making theory, this article demonstrates a method of evaluating alternative ISDAes to select relatively satisfactory one out of them, for which a fuzzy synthetic discrimination model is created. In particular, a typical summarized evaluation index system is established, too. Finally, the application of the above method to a practical information system (IS) is illustrated.

关键词： information system development approach(ISDA) factor analysis fuzzy selection fuzzy syntheticdiscrimination model

Influence of the electric field on carriers recombination zone in bilayer organic electroluminescent device

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Chinese Science Bulletin 2000年第17期45卷 1623-1628页

作者： Shengyi Yang Zhenjia Wang Zheng Xu xiaohong chen Yanbing Hou Xurong Xu No Jiaotong Univ Inst Optoelect Technol Beijing 100044 Peoples R China

The electroluminescence (EL) of bilayer devices (ITO/Polymer/Alqa/AI) made from two PPV derivatives (MN-PPV and MEH-PPV), respectively, and the influence of the organic layers’ thickness on the characteristics of the device are investigated. Different spectra and variations are observed for different thicknesses of Alq3 layer in this bilayer organic light-emitting diodes (LEDs) as increasing applied bias. Based on the energy level and field-assisted tunneling at the interface, we attributed these phenomena to electric field redistribution in the device and field-assisted charges being transported and tunneling through energy barrier at high electric field.

关键词： electroluminescence bilayer devices recombination zone carriers.

Study on Technology of Aluminizing and Internal Oxidation on Surface of Cu-Al-Y Alloy

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稀有金属材料与工程 2012年第S1期41卷 228-230页

作者： chen xiaohong Liu Ping Liu Xinkuan Ma Fengcang Li Wei Zhang Yi Tian Baohong Shanghai Univ Sci & Technol Sch Mat Sci & Engn Shanghai 200093 Peoples R China Henan Univ Sci & Technol Luoyang 471003 Peoples R China

Aluminum was deposited by diffusion into Cu-Al-Y alloy substrates by the pack-cementation *** was carried out in two kinds of container with pot-type and can-type,and the results are *** effects of various time and temperature on the coating characteristics of Cu-Al-Y was also *** result shows that the diffusion layer is nearly 170-200μm in thickness by aluminizing treatment at 900-950℃for 6-8 h in pot-type *** aluminized layers were observed by a scanning electron micrograph(SEM),we can found:A uniform coating was achieved on Cu-Al-Y alloy surface,relatively uniform thickness and even interfaces between the layers and the *** diffusion coefficient of Al in Cu-Al-Y alloys at 900℃in pot-type container can be calculated is 3.65×10-12 m 2 /s.

关键词： Cu-Al-Y alloy aluminized layer diffusion coefficient

Enhancement of corona discharge induced wind generation with carbon nanotube and titanium dioxide decoration

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Chinese Physics B 2019年第9期28卷 282-287页

作者： Jianchun Ye Jun Li xiaohong chen Sumei Huang Wei Ou-Yang Engineering Research Center for Nanophotonics and Advanced Instrument(Ministry of Education) School of Physics and Materials ScienceEast China Normal UniversityShanghai 200062China Department of Electronic Science and Technology Tongji UniversityShanghai 201804China

Dip-coated double-wall carbon nanotubes(DWCNTs) and titanium dioxide(TiO2) sol have been prepared and smeared onto the tip of a conductive iron needle which serves as the corona discharge anode in a needle-cylinder corona *** with the discharge electrode of a CNT-coated needle tip, great advancements have been achieved with the TiO_2/CNT-coated electrode, including higher discharge current, ionic wind velocity, and energy conversion efficiency,together with lower corona onset voltage and power *** parameters related to the discharge have been phenomenologically and mathematically studied for *** to the morphology reorientation of the CNT layer and the anti-oxidation of TiO_2, better performance of corona discharge induced wind generation of the TiO2/CNT-coated electrode system has been *** novel decoration may provide better thoughts about the corona discharge application and wind generation.

关键词： corona discharge induced wind wind velocity carbon nanotubes titanium dioxide