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Longitudinal control for person-following robots

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Journal of Intelligent and Connected Vehicles 2022年第2期5卷 88-98页

作者： Liang Wang Jiaming Wu Xiaopeng Li Zhaohui Wu Lin Zhu china Academy of Transportation Sciences BeijingChina Department of Architecture and Civil Engineering Chalmers University of TechnologyGothenburgSweden University of South Florida TampaFloridaUSA

Purpose–This paper aims to address the longitudinal control problem for person-following robots(PFRs)for the implementation of this ***/methodology/approach–Nine representative car-following models are analyzed from PFRs application and the linear model and optimal velocity model/full velocity difference model are qualified and selected in the PFR ***–A lab PFR with the bar-laser-perception device is developed and tested in the field,and the results indicate that the proposed models perform well in normal person-following ***/value–This study fills a gap in the research on PRFs longitudinal control and provides a useful and practical reference on PFRs longitudinal control for the related research.

关键词： Person following robot Longitudinal control model Parameter optimization

Lateral root elongation in maize is related to auxin synthesis and transportation mediated by N metabolism under a mixed NO_(3)^(–) and NH_(4)^(+) supply

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Journal of Integrative Agriculture 2024年第3期23卷 1048-1060页

作者： Peng Wang Lan Yang Xichao Sun Wenjun Shi Rui Dong Yuanhua Wu Guohua Mi Key Laboratory of Tobacco Biology and Processing of Ministry of Agriculture and Rural Affairs Tobacco Research InstituteChineseAcademy of Agricultural SciencesQingdao 266101China Department of Plant Nutrition College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China college of Resources Hunan Agricultural UniversityChangsha 410128China Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsTianjin 300191China

A mixed nitrate (NO_(3)^(–)) and ammonium (NH_(4)^(+)) supply can promote root growth in maize (Zea mays),however,the changes in root morphology and the related physiological mechanism under different N forms are still ***,maize seedlings were grown hydroponically with three N supplied in three different forms (NO_(3)^(–)only,75/25 NO_(3)^(–)/NH_(4)^(+)and NH_(4)^(+)only).Compared with sole NO_(3)^(–)or NH_(4)^(+),the mixed N supply increased the total root length of maize but did not affect the number of axial *** main reason was the increased total lateral root length,while the average lateral root (LR) length in each axle was only slightly *** addition,the average LR density of 2nd whorl crown root under mixed N was also *** with sole nitrate,mixed N could improve the N metabolism of roots (such as the N influx rate,nitrate reductase (NR) and glutamine synthase (GS)enzyme activities and total amino content of the roots).Experiments with exogenously added NR and GS inhibitors suggested that the increase in the average LR length under mixed N was related to the process of N assimilation,and whether the NR mediated NO synthesis participates in this process needs further ***,an investigation of the changes in root-shoot ratio and carbon (C) concentration showed that C transportation from shoots to roots may not be the key factor in mediating lateral root elongation,and the changes in the sugar concentration in roots further proved this ***,the synthesis and transportation of auxin in axial roots may play a key role in lateral root elongation,in which the expression of ZmPIN1B and ZmPIN9 may be involved in this *** study preliminarily clarified the changes in root morphology and explored the possible physiological mechanism under a mixed N supply in maize,which may provide some theoretical basis for the cultivation of crop varieties with high N efficiency.

关键词： maize NO_(3)^(–)/NH_(4)^(+)ratio lateral root elongation N assimilation indole-3-acetic acid

Bolt-grouting combined support technology in deep soft rock roadway

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International Journal of Mining Science and Technology 2016年第5期26卷 777-785页

作者： Chen Yanlong Meng Qingbin Xu Guang Wu Haoshuai Zhang Guimin State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining & Technology Department of Mining Engineering & Metallurgical Engineering Western Australian School of Mines Curtin University School of Mechanics and Civil Engineering China University of Mining & Technology

Analyzing the mineral composition, mechanical properties and ground stress testing in surrounding rock,the study investigated the failure mechanism of deep soft rock roadway with high stress. The boltgrouting combined support system was proposed to prevent such failures. By means of FLAC3D numerical simulation and similar material simulation, the feasibility of the support design and the effectiveness of support parameters were discussed. According to the monitoring the surface and deep displacement in surrounding rock as well as bolt axial load, this paper analyzed the deformation of surrounding rock and the stress condition of the support structure. The monitor results were used to optimize the proposed support scheme. The results of field monitors demonstrate that the bolt-grouting combined support technology could improve the surround rock strength and bearing capacity of support structure, which controlled the great deformation failure and rheological property effectively in deep soft rock roadway with high stress. As a result, the long term stability and safety are guaranteed.

关键词： Deep soft rock roadway Bolt-grouting support Numerical simulation Similar material simulation High stress

Preparation and utilization of phosphate biofertilizers using agricultural waste

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Journal of Integrative Agriculture 2015年第1期14卷 158-167页

作者： WANG Hong-yuan LIU Shen ZHAI Li-mei ZHANG Ji-zong REN Tian-zhi FAN Bing-quan LIU Hong-bin Key Laboratory of Nonpoint Source Pollution Control Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences

In this study, Aspergillus niger 1107 was isolated and identified as an efficient phosphate-solubilizing fungus （PSF）. This strain generated 689 mg soluble P L-1 NBRIP medium after 10 d of culture. To produce an affordable biofertilizer using A. niger 1107, the potential of widely available carrier materials for growth and maintenance of this strain were evaluated. The effects of sterilization procedures （autoclaving and gamma-ray irradiation） on the suitability of these carriers to maintain growth of the fungus were also investigated. The carrier materials were peat, corn cobs with 20% （w/w） perlite （CCP）, wheat husks with 20% （w/w） perlite （WHP）, and composted cattle manure with 20% （w/w） perlite （CCMP）. In the first 5-6 mon of storage, the carriers sterilized by gamma-ray irradiation maintained higher inoculum loads than those in carriers sterilized by autoclaving. However, this effect was not detectable after 7 mon of storage. For the P-biofertilizer on WHP, more than 2.0× 10^7 viable spores of A. niger g-1 inoculant survived after 7 mon of storage. When this biofertilizer was applied to Chinese cabbage in a pot experiment, there were 5.6×10^6 spores of A. niger g-1 soil before plant harvesting. In the pot experiment, Chinese cabbage plants grown in soil treated with peat- and WHP-based P-biofertilizers showed significantly greater growth （P〈0.05） than that of plants grown in soil treated with free-cell biofertilizer or the CCMP-based biofertilizer. Also, the peat- and WHP-based P-biofertilizers increased the available P content in soil.

关键词： biofertilizer carrier sterilization method phosphate biofertilizer P-solubilizing fungi Aspergillus niger

Larval diet affects development and reproduction of East Asian strain of the fall armyworm,Spodoptera frugiperda

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Journal of Integrative Agriculture 2021年第3期20卷 736-744页

作者： HE Li-mei WANG Teng-li CHEN Yu-chao GE Shi-shuai Kris AGWYCKHUYS WU Kong-ming State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops Institute of Applied EcologyFujian Agriculture and Forestry UniversityFuzhou 350002P.R.China

In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded china and has since impacted local maize,sorghum and other ***,we draw on laboratory experiments to show how different host crops(i.e.,maize,sorghum,wheat and rice)and artificial diet affect larval growth and adult reproduction of one local FAW *** diet affected development duration,pupation rate,survival and emergence rate of pupae,and *** adult *** attained the slowest larval development(19.4 days)on sorghum and the fastest(14.1 days)on artificial diet,with larvae attaining 99.6%survival on the latter food *** rice,FAW larvae attained survival rate of 0.4%and were unable to pupate *** rate and pupal survival varied substantially between artificial diet and live plantlets at different phenological *** weight was the highest(0.26 g)on artificial diet and the lowest(0.14 g)on sorghum,while FAW females reached the highest fecundity(699.7 eggs/female)on 2-leaf stage *** hatching rate equaled 93.6%on 4-or 5-leaf stage maize and 36.6%on artificial *** intrinsic rate of natural increase and the finite rate of increase varied between larval diets,reflecting how young maize leaves are the most suitable *** findings can help to refine laboratory rearing protocols,devise population forecasting models or guide the deployment of‘area-wide’integrated pest management(IPM)modules in FAW-invaded areas of china and other Asian countries.

关键词： developmental duration development fecundity life history insect mass-rearing biology invasion biology

Adult nutrition affects reproduction and flight performance of the invasive fall armyworm,Spodoptera frugiperda in china

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Journal of Integrative Agriculture 2021年第3期20卷 715-726页

作者： HE Li-mei JIANG Shan CHEN Yu-chao Kris AGWYCKHUYS GE Shi-shuai HE Wei GAO Xi-wu WU Kong-ming State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China college of Plant Protection China Agricultural UniversityBeijing 100193P.R.China college of Plant Protection Shenyang Agricultural UniversityShenyang 110866P.R.China State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops Institute of Applied EcologyFujian Agriculture and Forestry UniversityFuzhou 350002P.R.China college of Plant Protection Flenan Agricultural UniversityZhengzhou 450002P.R.China

Floral resources,such as carbohydrate-rich nectar or pollen,can bolster fitness and raise reproductive output of adult ***,we used laboratory experiments to assess how those plant-derived foods impact adult fecundity,reproductive physiology and flight performance of an invasive strain of the fall armyworm,Spodoptera frugiperda(FAW;Lepidoptera:Noctuidae)in *** specifically,supplementary feeding on bee pollen and honey enhanced FAW flight duration,testis size,ovarian development,longevity and adult *** adults attained the longest pre-oviposition(10.8 days)and oviposition period(6.8 days)and longevity(19.2 days)on 5%acacia *** access to 2.5%acacia honey and 2.5‰pine pollen,*** attained the highest mating rate(79.7%),fecundity(644.9 eggs/female)and egg hatching rate(82.3%).Feeding on honey further delayed decay of male testes,while ovarian development was enhanced when female moths were allowed access to 2.5%honey and 2.5‰pine *** feeding on 5%honey solution,*** engaged in flight over the longest duration(9.5 h),distance(29.9 km)and speed(3.1 km h-1).Honey had a comparatively greater effect on the above parameters than *** findings help decipher FAW invasion patterns and population dynamics,facilitate the development of nutritional attractants,and contribute to integrated pest management of this newly-invasive pest in eastern Asia.

关键词： supplementary nutrition fecundity adult reproduction flight parameter invasion biology nutritional physiology

Numerical solutions for two nonlinear wave equations

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Water Science and Engineering 2012年第4期5卷 410-418页

作者： Yi-feng ZHANG Rui-jie LI School of Civil Engineering Tianjin University Tianjin research Institute for Water Transport Engineering of Ministry of Transport Key Laboratory of Coastal Disaster and Defence of Ministry of Education Hohai University

The split-step pseudo-spectral method is a useful method for solving nonlinear wave equations. However, it is not widely used because of the limitation of the periodic boundary condition. In this paper, the method is modified at its second step by avoiding transforming the wave height function into a frequency domain function. Thus, the periodic boundary condition is not required, and the new method is easy to implement. In order to validate its performance, the proposed method was used to solve the nonlinear parabolic mild-slope equation and the spatial modified nonlinear Schrodinger （MNLS） equation, which were used to model the wave propagation under different bathymetric conditions. Good agreement between the numerical and experimental results shows that the present method is effective and efficient in solving nonlinear wave eouations.

关键词： nonlinear water wave equation parabolic mild-slope equation spatial MNLSequation," numerical method

Inter-annual changes in the aggregate-size distribution and associated carbon of soil and their effects on the straw-derived carbon incorporation under long-term no-tillage

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Journal of Integrative Agriculture 2018年第11期17卷 2546-2557页

作者： YIN Tao ZHAO Cai-xia YAN Chang-rong DU Zhang-liu HE Wen-qing Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China Key Laboratory of Prevention and Control of Residual Pollution in Agricultural Film Minstry of Agriculture Beijing 100081 P. R. China college of Plant Protection Agricultural University of Hebei Baoding 071001 P.R. China

Converting from conventional tillage to no-tillage influences the soil aggregate-size distribution and thus soil organic carbon （SOC） stabilization. However, the dynamics of soil aggregation and the straw-derived carbon （C） incorporation within aggregate fractions are not well understood. An experiment was established in 2004 to test the effects of two treatments, no-tillage with residue （NT） and conventional tillage without residue （CT）, on the soil aggregate-size distribution and SOC stabilization in a continuous maize （Zea mays L.） cropping system located in the semiarid region of northern china. Soil samples were collected from the 0-10 cm layer in 2008, 2010 and 2015, and were separated into four aggregate-size classes （〉2, 0.25-2, 0.053-0.25, and 〈0.053 mm） by wet-sieving. In each year, NT soil had a higher proportion of macroaggregates （i.e., 〉2 and 0.25-2 mm） and associated SOC concentration compared with CT. Additionally, to compare straw-derived C incorporation within NT and CT aggregate fractions, ^13C-labeled straw was incubated with intact NT and CT soils. After 90 days, the highest proportion of 13C-labeled straw-derived C was observed in the 〉2 mm fraction, and this proportion was lower in NT than that in CT soil. Overall, we conclude that long-term continuous NT increased the proportion of macroaggregates and the C concentration within macroaggregates, and the physical protection provided by NT is beneficial for soil C sequestration in the continuous maize cropping system in semiarid regions of northern china.

关键词： no-tillage aggregate-size distribution aggregate-associated carbon ^13C-labeled straw

Segmental nature of the Red River fault revealed by seismic anisotropy and geological structures

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Science china Earth Sciences 2024年第8期67卷 2423-2443页

作者： Ying LI Yuan GAO School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China

As the western boundary of the Sichuan-Yunnan block(SYB),the Red River fault(RRF)is a major fault that controls deep crustal movement and deformation in the southeast margin of the Tibetan Plateau and regulates middle-lower crustal *** data suggest that the RRF is segmented and exhibits distinct variations in seismicity,velocity structure and crustal deformation from north to *** anisotropy reveals a complex pattern of lateral spatial and vertical stratified distributions.(1)From the perspective of crustal stratification,in the upper crust,the fast wave polarization in the north segment of the RRF is complex and possibly influenced by the Sanjiang lateral collision zone and adjacent faults with varying *** fast wave polarization in the middle segment is in the NW-SE direction,indicating a localized area of closed down or locked up with consistent *** in the south segment,it presents a disordered pattern,signifying complex deep tectonics and stress conditions at the wedged intersection *** the middle-lower crust in the north and south segments of the RRF,the azimuthal anisotropy is strong and consistent with the spatial strike of the weak zone characterized by low-velocity and *** suggests a connection between the anisotropy and the material migration.(2)In the whole crustal scale,the fast wave directions in two sides of the RRF are consistent with the NW-SE tectonic *** indicates that the RRF,as a large fault potentially cutting through the whole crust,strongly controls the surrounding media.(3)In the lithospheric scale,the fast wave polarizations are oriented nearly E-W and independent of the fault strike,consistent with the low P-and S-wave velocity structures and positive radial anisotropy in the upper *** fast wave directions could be related to lithospheric olivine deformation and asthenospheric *** paper suggests a decoupling of deformation between the crust and the lithospheri

关键词： Red River fault Seismic anisotropy Geological structures Lithosphere Fault segmentation