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International Journal of Agricultural and Biological Engineering 2023年第3期16卷 130-142页

作者： Xinping Sun Hua Li Xindan Qi Dinghao Feng Jianqi Zhou Yongjian Wang Samuel Mbugua Nyambura Xiaoyu Zhang Xi Chen College of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China Key Laboratory of Intelligent Agricultural Equipment in Jiangsu province Nanjing Agricultural UniversityNanjing 210031China College of Engineering Nanjing Agricultural UniversityNanjing 210031China Jiangsu Xuzhou transportation planning and design institute Xuzhou 221000China

This study aimed to optimize a three-row air-suction Brassica chinensis precision metering device to improve the low seeding *** 17.0 Software was used to analyze the effect of different numbers of suction holes and different suction hole structures on the airflow *** was found that a suction hole number of 60 was beneficial to the flow field stability and a conical hole structure was beneficial to the adsorption of ***-Behnken design experiments were carried out with negative pressure,rotational speed,and hole diameter as the experimental *** optimal parameter combination was achieved when the negative pressure was 3.96 kPa,the rotational speed of the seeding plate was 1.49 rad/s and the hole diameter was 1.10 *** qualification rate of inner,middle,and outer rings were 87.580%,90.548%,and 90.117%,respectively,and the miss seeding rate of inner,middle,and outer rings were 10.915%,7.139%,and 5.920%,respectively.

关键词： Brassica chinensis metering device airflow field Box-Behnken design

Pseudo-Magnetotelluric 2D Inversion Technology of Magnetic-Source Transient Electromagnetics

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Applied Geophysics 2020年第5期17卷 784-795,903页

作者： Han Zi-qiang Jiang Shu-ping Fengbing School of Civil Engineering Chongqing Jiaotong UniversityChongqing 400074China Gansu transportation planning Survey and design institute Co.Ltd. Lanzhou 730030China School of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China

Based on the fact that it is diffi cult to implement optimum inversion using 2D and 3D forward modeling with magnetic-source transient electromagnetics(TEM),this paper explores a novel approach to the implementation of 2D magnetic-source TEM *** particular,we converted magnetic-source TEM data into magnetotelluric(MT)data and then used a 2D MT inversion method to implement a 2D magnetic-source TEM inversion ***,we studied the similarity between magnetic-source TEM waves and MT waves and between magnetic-source TEM all-time apparent resistivity and MT Cagniard apparent ***,we selected an optimal time-frequency transformation coeffi cient to implement rapid time-frequency transformation of all-time TEM apparent resistivity to MT Cagniard apparent ***,we conducted 1D pseudo-MT inversions of magnetic-source 1D TEM theoretical *** 1D inversion results demonstrated that the diff erence between the inversion parameters and model parameters was small,while the MT 1D inversion method could be used to conduct magnetic 1D TEM inversion within a certain margin of *** further conducted 2D pseudo-MT inversions of 3D magnetic-source TEM theoretical models,and the 2D inversion results indicated that selecting a joint 2D pseudo-MT transverse-electric(TE)and transverse-magnetic(TM)inversion method based on measuring the line above a 3D anomalous body can help to accurately implement a 2D inversion interpretation of the 3D TEM response.

关键词： TEM MT All-time apparent resistivity Time–frequency transformation 2D pseudo-MT inversion

Seismic behavior of large-scale FRP–recycled aggregate concrete–steel columns with shear connectors

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 823-844页

作者： Zeng Lan Li Lijuan Yang Xianqian Liu Feng School of Civil and transportation Engineering Guangdong University of Technology Guangzhou 510006 China MOE Key Laboratory of Disaster Forecast and Control in Engineering School of Mechanics and Construction Engineering Jinan University Guangzhou 510632 China Architectural design and Research institute of Guangdong province Guangzhou 510000 China

The application of fi ber-reinforced polymer (FRP) composites for the development of high-performance composite structural systems has received signifi cant recent research attention. A composite of FRP–recycled aggregate concrete (RAC)–steel column (FRSC), consisting of an outer FRP tube, an inner steel tube and annular RAC fi lled between two tubes, is proposed herein to facilitate green disposal of demolished concrete and to improve the ductility of concrete columns for earthquake resistance. To better understand the seismic behavior of FRSCs, quasi-static tests of large-scale basalt FRSCs with shear connectors were conducted. The infl uence of the recycled coarse aggregate (RCA) replacement percentage, shear connectors and axial loading method on the lateral load and deformation capacity, energy dissipation and cumulative damage were analyzed to evaluate the seismic behavior of FRSCs. The test results show that FRSCs have good seismic behavior, which was evidenced by high lateral loads, excellent ductility and energy dissipation capacity, indicating RAC is applicable in FRSCs. Shear connectors can signifi cantly postpone the steel buckling and increase the lateral loads of FRSCs, but weaken the deformation capacity and energy dissipation performance.

关键词： recycled aggregate concrete (RAC) fi ber-reinforced polymer (FRP) FRP–RAC–steel column (FRSC) shear connector seismic behavior

Threshold values of traffic flow for the provision of exclusive bus lanes

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Journal of Beijing institute of Technology 2013年第3期22卷 342-349页

作者：孙锋王殿海马东方金盛 College of transportation Jilin University College of transportation Shandong University of Technology College of Civil Engineeringand Architecture Zhejiang University

A simulation network model was established using VISSIM software and verified by the T- test. The model took into consideration the road conditions, pedestrian crossing, traffic composi- tion, bus stops and traffic signal. The operating characteristics of buses and cars under different flow conditions were studied using the simulation model, and the speed-flow models of buses and cars were established based on the simulation results. Finally, the threshold values of traffic flow for the provision of exclusive bus lanes was determined with the target of optimal travel benefits （per capi- ta） , which would provide a basis for the planning and design of exclusive bus lanes on urban roads.

关键词： public transportation exclusive bus lane traffic management speed-flow model

Ecosystem service values of gardens in the Yellow River Basin,China

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Journal of Arid Land 2022年第3期14卷 284-296页

作者： GE Qianqian XU Wenjie FU Meichen HAN Yingxin AN Guoqiang XU Yuetong School of Land Science and Technology China University of Geosciences(Beijing)Beijing 100083China China Land Surveying and planning institute Beijing 100035China shandong Urban and Rural planning design institute Jinan 250013China Territorial Spatial planning institute of shandong province Jinan 250014China College of Geography and Environment Shandong Normal UniversityJinan 250358China Key Laboratory of Land Use Ministry of Natural ResourcesShandong BasisJinan 250014China

Studies on the ecosystem service value(ESV)of gardens are critical for informing evidence-based land management practices based on an understanding of the local *** analyzing equivalent value factors(EVFs),this paper evaluated the values of 11 ecosystem services of gardens in the Yellow River Basin of China in ***-precision land use survey data were used to improve the accuracy of the land use classification,garden areas,and spatial distribution of the ESVs of *** results showed that garden ecosystem generally had high ESVs,especially in terms of the ESV of food production,which is worthy of further research and application to the practice of land use planning and ***,the value of one standard EVF of ecosystem services in 2019 was 3587.04 CNY/(hm^(2)·a),and the ESV of food production of gardens was much higher than that of *** ecosystem provided an ESV of 1348.66×10^(8)CNY/a in the Yellow River *** areas with the most concentrated ESVs of gardens were located in four regions:downstream in the shandong-Henan zone along the Yellow River,mid-stream in the Shanxi-Shaanxi zone along the Yellow River,the Weihe River Basin,and upstream in the Qinghai-Gansu-Ningxia-Inner Mongolia zone along the Yellow *** spatial correlation of the ESVs in the basin was significant(global spatial autocorrelation index Moran's I=0.464),which implied that the characteristics of high ESVs adjacent to high ESVs and low ESVs adjacent to low ESVs are *** the Yellow River Basin,the contribution of the ESVs of gardens to the local environment and economy varied across *** also put forward some suggestions for promoting the construction of ecological civilization in the Yellow River *** findings of this study provide important contributions to the research of ecosystem service evaluation in the Yellow River Basin.

关键词： ecosystem service evaluation garden ecosystem equivalent value factors spatial autocorrelation analysis Yellow River Basin

Salt freezing resistance improvement of cement-based materials incorporated with calcined layered double hydroxide

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Journal of Traffic and transportation Engineering(English Edition) 2023年第3期10卷 427-440页

作者： Jinyang Huo Tonghuan Zhang Zhenjun Wang Xiaofeng Wang Xin Ji Pei Wang School of Materials Science and Engineering Chang'an UniversityXi'an 710064China Engineering Research Center of transportation Materials of Ministry of Education Chang'an UniversityXi'an 710064China Henan Communications planning&design institute Co. Ltd.Zhengzhou 450052China

Salt freezing damage has severe impacts on durability of cement-based materials(CBMs).Calcined layered double hydroxide(CLDH),as an efficient environmental-friendly adsorption material,can impart excellent salt freezing resistance to *** this work,salt freezing resistance improvement of CBMs incorporated with CLDH was experimentally evaluated by chloride binding capacity,mass loss rate,relative dynamic elastic modulus,setting time,compressive strength,and micro structure *** these,the salt freezing damage model was established to effectively express the quantitative relationship between influencing factors and evaluation indexes of the salt freezing resistance of *** show that CLDH can reconstruct its original layered structure to form reconstructed layered double hydroxide(RLDH).RLDH combines with chloride ions to form RLDH-Cl recrystallization,which can improve chloride binding capacity and pore structures of CBMs to relieve the salt freezing *** salt freezing damage model indicates that the suitable CLDH content can evidently alleviate the salt freezing damage,which facilitates the quantitative analysis of the effect of CLDH on the salt freezing resistance of CBMs.

关键词： Cement-based materials Calcined layered double hydroxide Salt freezing resistance Micro structure Salt freezing damage

Discussion on Individual Expected Maturity of Populus canadensis Moench

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Agricultural Biotechnology 2018年第5期7卷 168-170页

作者： Xingyun GAO Mingliang WEI Kehua WANG Hongbo QIAO Dequan ZHANG Dejin DONG Forestry Survey and planning institute of shandong province Jinan 250014China

Through the study of parse wood materials in shandong province, the fitting empirical equation of tree growth was obtained, a function with tree growth was a variable and time as an independent variable. Through mathematical operations such as function derivation, the mature age of tree growth was obtained. The obtained expected maturity age for Populus canadensis Moench forest was 11 a for pulp material, 26 a for pillar materials and 41 a for peeler. And the application, research directions and precautions of the mature ages were proposed.

关键词： Expected maturity age Empirical equation Parse wood

Quasi-Developable B-Spline Surface design with Control Rulings

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Journal of Computer Science & Technology 2022年第5期37卷 1221-1238页

作者： Zi-Xuan Hu Peng-Bo Bo Cai-Ming Zhang School of Computer Science and Technology Harbin Institute of TechnologyWeihai 264209China shandong Co-Innovation Center of Future Intelligent Computing Yantai 264005China shandong province Key Laboratory of Digital Media Technology Shandong University of Finance and EconomicsJinan 250061China

We propose a method for generating a ruled B-spline surface fitting to a sequence of pre-defined ruling lines and the generated surface is required to be ***,the terminal ruling lines are treated as hard *** from existing methods that compute a quasi-developable surface from two boundary curves and cannot achieve explicit ruling control,our method controls ruling lines in an intuitive way and serves as an effective tool for computing quasi-developable surfaces from freely-designed *** treat this problem from the point of view of numerical optimization and solve for surfaces meeting the distance error tolerance allowed in *** performance and the efficacy of the proposed method are demonstrated by the experiments on a variety of models including an application of the method for path planning in 5-axis computer numerical control(CNC)flank milling.

关键词： developable surface surface modeling B-spline surface numerical optimization

Study on Mature Age of An Individual Robinia pseudoacacia

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Agricultural Biotechnology 2018年第5期7卷 184-185,190页

作者： Hongbo QIAO Kehua WANG Xingyun GAO Xueqiang ZHANG Dequan ZHANG Forestry Survey and planning institute of shandong province Jinan 250014China

Through the study of parse wood materials, the fitting empirical equation of tree growth was obtained, a function with tree growth as a variable and time as an independent variable. The mature age of tree growth was obtained through mathematical operations such as function derivation. The obtained expected maturity ages for the actual forests of Robinia pseudoacacia were 36, 46 and 56 a, respectively, which could be the mature ages for commercial forest, protection forest and special-purpose forest. And the application, research directions and precautions of the mature ages were proposed.

关键词： Mature age Empirical equation Parse wood

Study on Mature Age of An Individual Pinus thunbergii Parl

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Agricultural Biotechnology 2018年第5期7卷 156-158页

作者： Kehua WANG Hongbo QIAO Xingyun GAO Wei ZHANG Mingliang WEI Fengzhen WANG Xueqiang ZHANG Forestry Survey and planning institute of shandong province Jinan 250014China

Through the study of parse wood materials, the fitting empirical equation of tree growth was obtained, a function with tree growth as a variable and time as an independent variable. Through mathematical operations such as function derivation, the mature age of tree growth was obtained. The obtained maturity age for the actual forest of Pinus thunbergii Parl was 51 a, and the ideal mature age was 66 a. And the application, research directions and precautions of the mature ages were proposed.

关键词： Mature age Empirical equation Parse wood