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LSDA-APF:A Local Obstacle Avoidance Algorithm for Unmanned Surface Vehicles Based on 5G Communication Environment

工程与科学中的计算机建模(英文) 2024年第1期138卷 595-617页

作者： Xiaoli Li Tongtong Jiao jinfeng ma Dongxing Duan Shengbin Liang School of Software Henan UniversityKaifeng475004China

In view of the complex marine environment of navigation,especially in the case of multiple static and dynamic obstacles,the traditional obstacle avoidance algorithms applied to unmanned surface vehicles(USV)are prone to fall into the trap of local optimization.Therefore,this paper proposes an improved artificial potential field(APF)algorithm,which uses 5G communication technology to communicate between the USV and the control center.The algorithm introduces the USV discrimination mechanism to avoid the USV falling into local optimization when the USV encounter different obstacles in different scenarios.Considering the various scenarios between the USV and other dynamic obstacles such as vessels in the process of performing tasks,the algorithm introduces the concept of dynamic artificial potential field.For the multiple obstacles encountered in the process of USV sailing,based on the International Regulations for Preventing Collisions at Sea(COLREGS),the USV determines whether the next step will fall into local optimization through the discriminationmechanism.The local potential field of the USV will dynamically adjust,and the reverse virtual gravitational potential field will be added to prevent it from falling into the local optimization and avoid collisions.The objective function and cost function are designed at the same time,so that the USV can smoothly switch between the global path and the local obstacle avoidance.The simulation results show that the improved APF algorithm proposed in this paper can successfully avoid various obstacles in the complex marine environment,and take navigation time and economic cost into account.

关键词： Unmanned surface vehicles local obstacle avoidance algorithm artificial potential field algorithm path planning collision detection

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Carbon Capture and Storage:History and the Road Ahead

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Engineering 2022年第7期8卷 33-43页

作者： jinfeng ma Lin Li Haofan Wang Yi Du Junjie ma Xiaoli Zhang Zhenliang Wang Department of Geology Northwest UniversityXi’an 710069China National and Local Joint Engineering Research Center of Carbon Capture and Storage Technology Xi’an 710069China Shaanxi Key Laboratory for Carbon Neutral Technology Xi’an 710069China College of Urban and Environmental Sciences Northwest UniversityXi’an 710127China

The large-scale deployment of carbon capture and storage(CCS)is becoming increasingly urgent in the global path toward net zero emissions;however,global CCS deployment is significantly lagging behind its expected contribution to greenhouse gas emission reduction.Reviewing and learning from the examples and history of successful CCS practices in advanced countries will help other countries,including China,to promote and deploy CCS projects using scientific methods.This paper shows that the establishment of major science and technology CCS infrastructures in advanced countries has become the main source of CCS technological innovation,cost reduction,risk reduction,commercial promotion,and talent training in the development and demonstration of key CCS technologies.Sound development of CCS requires a transition from pilot-scale science and technology infrastructures to large-scale commercial infrastructures,in addition to incentive policies;otherwise,it will be difficult to overcome the technical barriers between small-scale demonstrations and the implementation of million-tonne-scale CCS and ten-million-tonne-scale CCS hubs.Geological CO_(2) storage is the ultimate goal of CCS projects and the driving force of CO_(2) capture.Further improving the accuracy of technologies for the measurement,monitoring,and verification(MMV)of CO_(2) storage capacity,emission reduction,and safety remains a problem for geological storage.CO_(2) storage in saline aquifers can better couple multiple carbon emission sources and is currently a priority direction for development.Reducing the energy consumption of lowconcentration CO_(2) capture and the depletion of chemical absorbents and improving the operational efficiency and stability of post-combustion CO_(2) capture systems have become the key constraints to largescale CCS deployment.Enhanced oil recovery(EOR)is also important in order for countries to maximize fossil fuel extraction instead of importing oil from less environmentally friendly oil-producing countries.

关键词： CCS research facility Net GHG emission reduction Energy consumption Monitoring

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Automated multi-scale classification of the terrain units of the Jiaxie Guyots and their mineral resource characteristics

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Acta Oceanologica Sinica 2022年第7期41卷 128-138页

作者： Yong Yang Gaowen He Yonggang Liu jinfeng ma Zhenquan Wei Binbin Guo Institute of Geology Chinese Academy of Geological SciencesBeijing100037China Southern marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou511458China Guangzhou marine Geological Survey Key Laboratory of Marine Mineral Resources of Ministry of Natural ResourcesGuangzhou510075China

Given the advances in satellite altimetry and multibeam bathymetry,benthic terrain classification based on digital bathymetric models(DBMs)has been widely used for the mapping of benthic topographies.For instance,cobaltrich crusts(CRCs)are important mineral resources found on seamounts and guyots in the western Pacific Ocean.Thick,plate-like CRCs are known to form on the summit and slopes of seamounts at the 1000–3000 m depth,while the relationship between seamount topography and spatial distribution of CRCs remains unclear.The benthic terrain classification of seamounts can solve this problem,thereby,facilitating the rapid exploration of seamount CRCs.Our study used an EM122 multibeam echosounder to retrieve high-resolution bathymetry data in the CRCs contract license area of China,i.e.,the Jiaxie Guyots in 2015 and 2016.Based on the DBM construted by bathymetirc data,broad-and fine-scale bathymetric position indices were utilized for quantitative classification of the terrain units of the Jiaxie Guyots on multiple scales.The classification revealed four first-order terrain units(e.g.,flat,crest,slope,and depression)and eleven second-order terrain units(e.g.,local crests,depressions on crests,gentle slopes,crests on slopes,and local depressions,etc.).Furthermore,the classification of the terrain and geological analysis indicated that the Weijia Guyot has a large flat summit,with local crests at the southern summit,whereas most of the guyot flanks were covered by gentle slopes.“Radial”mountain ridges have developed on the eastern side,while large-scale gravitational landslides have developed on the western and southern flanks.Additionally,landslide masses can be observed at the bottom of these slopes.The coverage of local crests on the seamount is∼1000 km^(2),and the local crests on the peak and flanks of the guyots may be the areas where thick and continuous plate-like CRCs are likely to occur.

关键词： bathymetric position index multi-scale terrain classification local crest western Pacific seamount cobalt-rich crusts

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Consideration of climate change impacts will improve the efficiency of protected areas on the Qinghai-Tibet Plateau

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Ecosystem Health and Sustainability 2022年第1期8卷 181-193页

作者： Zijian Lu Liangxu Wang Nan Meng Xuhuan Dai Jingyi Zhu Yanzheng Yang Ruonan Li jinfeng ma Hua Zheng State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijingChina School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghaiChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina Institute of International Rivers and Eco-Security Yunnan UniversityKunmingChina

The protection of migratory birds and their habitats is important to the ecological stability of the Qinghai-Tibet Plateau(QTP).Currently protected areas(PAs)were designed in accordance with species distribution patterns under current climatic conditions,thus ignoring climate change will lead to a decrease in the protection efficiency of PAs.In this study,using the flagship species Grus nigricollis,as an example,we used the maximum entropy(maxEnt)model to simulate the distributions and conservation status of G.nigricollis and optimized the existing PA boundaries.The results showed that(1)suitable habitat-for G.nigricollis accounts for 12.48%of the QTP area,and the PAs established under current climatic conditions cover 17.84%of this suitable habitat area;(2)future climate changes will influence the distribution and quality of G.nigricollis habitats,and the average protection efficiency of the current PAs in four climatic scenarios will decrease from 17.84%to 15.31%;and(3)through optimization,the efficiency of existing PAs can be increased by 0.75 times and reach 28.37%,indicating PA planning must consider not only current climate conditions but also the effects of climate changes.Our results aim to address shortcomings in the conservation efficiency of PAs and provide an example for resolving mismatched PA boundaries and habitat changes for species.

关键词： Migratory bird protected area climate change grus nigricollis

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Optimizing the operation of the Qingshitan Reservoir in the Lijiang River for multiple human interests and quasi-natural flow maintenance

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Journal of Environmental Sciences 2012年第11期24卷 1923-1928页

作者： Qiuwen Chen Duan Chen Ruiguang Han Ruonan Li jinfeng ma Koen Blanckaert Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Three Gorges University Yichang 443002China Changjiang River Scientific Research Institute Wuhan 430010China Laboratory of Hydraulic Constructions School of ArchitectureCivil and Environment EngineeringLausanneSwitzerland Haihe Water Conservancy Commission Tianjin 300170China

For reservoir operation, maintaining a quasi-natural flow regime can benefit river ecosystems, but may sacrifice human interests. This study took the Qingshitan Reservoir in the Lijiang River as a case, and developed an optimization model to explore a trade-off solution between social-economic interests and nature flow maintenance on a monthly base. The objective function considered irrigation, cruise navigation and water supply aspects. An index of flow alteration degree was proposed to measure the difference between the regulated discharge and the natural flow. The index was then used as an additional constraint in the model besides the conventional constraints on reservoir safety. During model solving, different criteria were applied to the index, representing various degrees of alteration of the natural flow regime in the river. Through the model, a relationship between social-economic interests and flow alteration degree was established. Finally, a trade-off solution of the reservoir operation was defined that led to a favorable social-economic benefit at an acceptable alteration of the natural flow.

关键词： reservoir operation optimization model flow alteration trade-off solution

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Effects of the seasonal variation in chlorophyll concentration on sea surface temperature in the global ocean

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Acta Oceanologica Sinica 2021年第11期40卷 50-61页

作者： jinfeng ma Hailong Liu Pengfei Lin Haigang Zhan State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Southern marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

The effects of biological heating on the upper-ocean temperature of the global ocean are investigated using two ocean-only experiments forced by prescribed atmospheric fields during 1990–2007,on with fixed constant chlorophyll concentration,and the other with seasonally varying chlorophyll concentration.Although the existence of high chlorophyll concentrations can trap solar radiation in the upper layer and warm the surface,cooling sea surface temperature(SST)can be seen in some regions and seasons.Seventeen regions are selected and classified according to their dynamic processes,and the cooling mechanisms are investigated through heat budget analysis.The chlorophyll-induced SST variation is dependent on the variation in chlorophyll concentration and net surface heat flux and on such dynamic ocean processes as mixing,upwelling and advection.The mixed layer depth is also an important factor determining the effect.The chlorophyll-induced SST warming appears in most regions during the local spring to autumn when the mixed layer is shallow,e.g.,low latitudes without upwelling and the mid-latitudes.Chlorophyll-induced SST cooling appears in regions experiencing strong upwelling,e.g.,the western Arabian Sea,west coast of North Africa,South Africa and South America,the eastern tropical Pacific Ocean and the Atlantic Ocean,and strong mixing(with deep mixed layer depth),e.g.,the mid-latitudes in winter.

关键词： sea surface temperature heat budget upwelling mixing biological heating

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鄂尔多斯盆地CCS-EOR项目CO_(2)泄漏环境风险评估

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环境监测管理与技术 2024年第2期36卷 64-68页

作者：薛璐马俊杰王浩璠李琳马劲风西北大学碳中和学院(榆林) 陕西西安710069 榆林学院生命科学学院陕西榆林719000 二氧化碳捕集与封存国家与地方工程研究中心陕西西安710127 西北大学地质学系陕西西安710069

以鄂尔多斯盆地乔家洼CCS-EOR项目为例,通过工程活动指标分解及选项设计,形成涵盖油区特征、储盖层特征、工程设计、工程监管4大类20个指标的环境风险可能性判定指标体系,利用问卷调查和专家打分法,界定驱油工程环境风险可能性。结合国... 详细信息

以鄂尔多斯盆地乔家洼CCS-EOR项目为例,通过工程活动指标分解及选项设计,形成涵盖油区特征、储盖层特征、工程设计、工程监管4大类20个指标的环境风险可能性判定指标体系,利用问卷调查和专家打分法,界定驱油工程环境风险可能性。结合国内外文献分析,开展项目对空气、土壤和微生物、作物、动物及人群等环境风险受体的影响程度界定,基于界定结果,按照风险评估矩阵,对该工程CO_(2)泄漏环境风险水平的评估结论为低风险,在后期运行过程中应强化风险防范与监测。

关键词： CO_(2)泄漏风险评估环境影响 CCS-EOR项目鄂尔多斯盆地

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基于机器学习方法的景观斑块属性对物种丰富度的影响研究

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生态学报 2024年第11期44卷 4820-4830页

作者：付遇堤文志李若男马金锋郑华中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 中国科学院大学北京100049

景观破碎化对物种的影响依赖于斑块属性,斑块属性体现了斑块的类型、面积、形状及其与周围斑块间关系。然而,在破碎化农业景观中这些斑块属性对关键物种的联合影响仍知之甚少。选取中国海南地区的典型农业破碎化景观,实测了180个斑块中... 详细信息

景观破碎化对物种的影响依赖于斑块属性,斑块属性体现了斑块的类型、面积、形状及其与周围斑块间关系。然而,在破碎化农业景观中这些斑块属性对关键物种的联合影响仍知之甚少。选取中国海南地区的典型农业破碎化景观,实测了180个斑块中三类关键物种,分别为害虫-橡胶材小蠹虫(Xyleborus affinis)、传粉昆虫-中华蜜蜂(Apis cerana)和天敌物种-玉米螟赤眼蜂(Trichogrammatid ostriniae Pang et Chen),刻画了各斑块属性,包括斑块类型、斑块面积、形状指数、距天然林距离、是否与橡胶接触、景观中天然林所占比例、是否有林下植物,并使用3种机器学习模型(神经网络、随机森林、支持向量机)拟合斑块属性与三类物种丰富度关系,解析斑块属性的相对重要性。结果表明,与支持向量机和神经网络相比,随机森林模型对三个物种的丰富度预测效果均最好,其R2在橡胶材小蠹虫、中华蜜蜂和赤眼蜂中分别达到0.785、0.845和0.798;基于随机森林模型的结果表明,斑块类型对橡胶材小蠹虫和中华蜜蜂丰富度相对重要性高于其他斑块属性;斑块面积对赤眼蜂丰富度影响高于其他斑块属性,且与斑块类型存在交互作用;橡胶林中橡胶材小蠹虫与中华蜜蜂丰富度高于天然林和其他斑块类型,玉米螟赤眼蜂丰富度则在天然林与农田中最高。研究揭示了斑块属性对不同物种丰富度的相对影响,阐明了斑块类型在不同物种中的重要作用,并证实了机器学习是推导斑块属性对物种影响的有效方法。

关键词：农业景观景观破碎化斑块属性物种多样性昆虫丰富度机器学习

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Superoxide Dismutase Plays an Important Role in maize Resistance to Soil CO_(2)Stress

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Acta Geologica Sinica(English Edition) 2023年第3期97卷 995-1001页

作者： XUE Lu ma Junjie HU Qian ma jinfeng Carbon Neutral College(Yulin) Northwest UniversityXi’an 710069China College of Life Science Yulin UniversityYulinShaanxi 719000China National&Local Joint Engineering Research Center of Carbon Capture and Storage Technology Northwest UniversityXi’an 710127China Shaanxi Key Laboratory for Carbon Neutral Technology Northwest UniversityXi’an 710069China Department of Geology Northwest UniversityXi’an 710069China College of Urban and Environmental Sciences Northwest UniversityXi’an 710127China Oil Production Plant No.1 Sinopec North China Oil&Gas CompanyXianyangShaanxi 712000China

CO_(2)capture and storage(CCS)has the risk of CO_(2)leakage,and this leakage always increases soil CO_(2)concentration,and the long-term CO_(2)stress damages crop production in farmland.Using maize,the growth characteristics,such as plant height and yield,and physiological indexes(osmoregulation substances and antioxidant enzymes)were explored under different simulative CO_(2)leakage conditions.Further,the relationship between maize physiological indexes and soil CO_(2)concentration was analyzed,showing that soil CO_(2)stress inhibited maize growth to a certain extent,resulting in shorter plants,thinner stems and lower kernel yield.With an increase in soil CO_(2)concentration,the contents of malondialdehyde,soluble sugar and soluble protein in maize leaves increased;with continuing stress,the increase rate of malondialdehyde was greatly augmented,whereas the increase rates of soluble sugar and soluble protein decreased.With extended CO_(2)stress,the activity of the enzyme superoxide dismutase(SOD)increased continuously,while the activities of catalase and peroxidase first increased and then decreased.Superoxide dismutase activity was closely correlated with soil CO_(2)concentration(r=0.762),and responded quickly to the change of soil CO_(2)concentration(R~2=0.9951).Therefore,SOD plays an important role in maize resistance to soil CO_(2)stress.This study will help further understanding of the mechanism of maize tolerance to soil CO_(2)stress,providing a theoretical basis for agricultural production in CCS project areas.

关键词： CO_(2)capture and storage CO_(2)leakage soil CO_(2)stress antioxidant enzyme system maize

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Distinct BSRs and their implications for natural gas hydrate formation and distribution at the submarine makran accretionary zone

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Journal of Oceanology and Limnology 2021年第5期39卷 1871-1886页

作者： Bin LIU Waseem Haider SYED Jiangxin CHEN Xiguang DENG Li YANG Leonardo AZEVEDO Minliang DUAN Tingting WU jinfeng ma Keliang LI Key Laboratory of marine Mineral Resources Ministry of Natural ResourcesGuangzhou Marine Geological SurveyGuangzhou 510760China National Institute of Oceanography Karachi 75600Pakistan Key Laboratory of Gas Hydrate Ministry of Natural ResourcesQingdao Institute of Marine GeologyQingdao 266071China Laboratory for marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China CERENA/Instituto Superior Técnico Lisbon UniversityLisbon 1049-001Portugal Key Lab of Submarine Geosciences and Prospecting Techniques MOE andCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China

To investigate the nature of gas hydrates in the makran area,new high-resolution geophysical data were acquired between 2018-2019.The data collected comprise multibeam and two-dimensional multi-channel seismic reflection data.The multibeam bathymetry data show East-North-East(ENE)ridges,piggy-back basins,canyon and channel systems,and the morphology of the abyssal plain.Continuous and discontinuous bottom simulating reflectors(BSRs)occur in the piggy-back basins on most of the seismic profiles available.The BSRs cut the dipping layers with strong amplitude and reversed polarity.Discontinuous BSRs indicate a transition along a dipping high-permeable sand layers from gas-rich segment to the gas hydrate-bearing segment and sugge st alternating sediments of fine and relatively coarse grain size.Double BSRs are highly dynamic and attributed to slumps occurring in the study area.The BSRs induced by slumps are located both at deep and shallow depths,responding to the temperature or pressure variation.For the first time,BSRs are observed in the abyssal plain of the makran area,being associated with anticline structures,which do not show large spatial continuity and are strongly conditioned by structural conditions such as anticlines and fluid migration pathways,including deep fault,gas chimney,and high-permeable sedimentary layer.Our results may help to assess the gas hydrate potential within the piggy-back basins and to determine the most promising target areas.Moreover,results about the abyssal plain BSR may help to locate hydrocarbon reservoirs in the deep ocean.

关键词： gas hydrate-bearing sand-prone sediments double bottom simulating reflector(BSR) multiple BSR canyon channel system abyssal plain

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