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A review of hydrological/water-quality models

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Frontiers of Agricultural Science and Engineering 2014年第4期1卷 267-276页

作者： liangliang gao Daoliang LI College of Information Science and Engineering Shandong Agricultural UniversityTai’an 271018China College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China

Water quality models are important in predicting the changes in surface water quality for environmental management.A range of water quality models are wildly used,but every model has its advantages and limitations for specific *** aim of this review is to provide a guide to researcher for selecting a suitable water quality *** well known water quality models were selected for this review:SWAT,WASP,QUALs,MIKE 11,HSPF,CE-QUAL-W2,ELCOM-CAEDYM and *** model is described according to its intended use,development,simulation elements,basic principles and applicability(e.g.,for rivers,lakes,and reservoirs and estuaries).Currently,the most important trends for future model development are:(1)combination models—individual models cannot completely solve the complex situations so combined models are needed to obtain the most appropriate results,(2)application of artificial intelligence and mechanistic models combined with nonmechanistic models will provide more accurate results because of the realistic parameters derived from nonmechanistic models,and(3)integration with remote sensing,geographical information and global position systems(3S)-3S can solve problems requiring large amounts of data.

关键词： water quality models applications future trends

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综采工作面高位裂隙带瓦斯抽采技术优化应用

能源技术与管理 2024年第5期49卷 33-35页

作者：高亮亮解文杰孙传利中检集团公信安全科技有限公司山东枣庄277100

基于18303工作面回采期间上隅角及采空区频繁出现瓦斯超限现象,根据工作面瓦斯抽采现状,分析了工作面瓦斯主要来源于上覆裂隙带赋存瓦斯,通过对工作面瓦斯抽采技术进行合理优化,提出了高位裂隙钻孔瓦斯抽采技术。实际应用效果表明,布置... 详细信息

基于18303工作面回采期间上隅角及采空区频繁出现瓦斯超限现象,根据工作面瓦斯抽采现状,分析了工作面瓦斯主要来源于上覆裂隙带赋存瓦斯,通过对工作面瓦斯抽采技术进行合理优化,提出了高位裂隙钻孔瓦斯抽采技术。实际应用效果表明,布置高位裂隙钻孔后,降低了裂隙带瓦斯浓度,减少了裂隙瓦斯涌出量,实测工作面后期回采过程中上隅角瓦斯浓度控制在0.4%以下,采空区瓦斯控制在2.1%以下,取得了显著的应用成效。

关键词：综采工作面裂隙瓦斯高位钻孔抽采效果

The Impact of Farmland Transfers on Agricultural Investment in China:A Perspective of Transaction Cost Economics

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China & World Economy 2019年第1期27卷 93-109页

作者： liangliang gao Dingqiang Sun Cuiping Ma Chinese Academy of Social Sciences China College of Economics and Management Nanjing Agricultural UniversityChina

There is growing concern that farmland transfers lead to less agricultural investment, which may adversely affect agricultural productivity growth in *** research has primarily focused on the differences between owned cultivated land and rented plots,but little is known about how farmland transfers between relatives,which are popular in rural China,specifically affect agricultural *** this paper,we present a conceptual framework of transaction cost economics to compare different contracting strategies in China's farmland rental *** farmland rental markets in China are immature,land transfer between relatives establishes bilateral governance,which has the advantage of addressing the opportunistic activities of both parties and can ultimately increase investment by *** on data from two waves of household surveys,we empirically examine the impact of bilateral governance on the application of organic fertilizer,an indicator for agricultural *** findings show that apart from economic factors, kinship is important to the functioning of farmland rental markets in rural areas.

关键词： agricultural investment farmland rental market governance structure transaction cost economics

Identifying the Turning Point of the Urban-Rural Relationship： Evidence from Macro Data

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China & World Economy 2018年第1期26卷 106-126页

作者： liangliang gao Jiao Yan Yue Du Rural Development Institute Chinese Academy of Social Sciences China School of Economics and Resource Management Beijing Normal University China Graduate School of Chinese Academy of Social Sciences China

The urban and rural dual structure is a defining characteristic of the social and economic development process in China. With rapid urbanization, remarkable development of agriculture and rural modernization, the relationship between urban and rural areas is undergoing significant changes in China. Using macro data, we find that the relationship between urban and rural areas started to change in 2010. The transition has mainly been reflected in three dimensions： agriculture, rural areas and farmers. First, agricultural versatility has gradually increased, and the number of participants in leisure agriculture and rural tourism has grown rapidly since 2010. Second, the rural employment rate has risen gradually, and the share of rural employees in the tertiary sector has grown markedly. Third, the urban-rural income ratio and consumption ratio have begun to decrease, and the levels of consumption of domestic tourism by urban and rural residents are becoming small.

关键词： agricultural diversification urban-rural consumption ratio urban-rural income ratio urban-rural relationship

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工作面监控视频清晰化应用技术研究

煤炭工程 2024年第7期56卷 98-104页

作者：张杰郭建军王永刚高巾栋曹敏方云峰于继斌高亮亮国能包头能源有限责任公司李家壕煤矿内蒙古鄂尔多斯017000 北京天玛智控科技股份有限公司北京101320

针对井下工作面监控视频的视觉清晰化问题,首先提出一种监控摄像仪防尘自动疏水方法,利用疏水涂层制备摄像仪视窗,有效减少煤尘、水雾等附着,提高监控视频画面的可视化监控效果。针对工作面工况条件下粉尘雾气导致监控视频图像质量下降... 详细信息

针对井下工作面监控视频的视觉清晰化问题,首先提出一种监控摄像仪防尘自动疏水方法,利用疏水涂层制备摄像仪视窗,有效减少煤尘、水雾等附着,提高监控视频画面的可视化监控效果。针对工作面工况条件下粉尘雾气导致监控视频图像质量下降问题,提出一种监控视频图像实时去雾算法。通过实时去雾处理后监控图像峰值信噪比保持在28.2左右,使得监控图像特征信息很好保持的同时,增强工作面监控视觉效果。在监控视频图像视觉畸变矫正技术研究过程中,提出一种工作面监控视频图像校正方法,充分利用视频图像内部特征信息,无需外部标定实现监控视频图像边缘畸变校正。实验表明,文章提出的工作面监控视频清晰化技术一定程度上能够满足实际生产需求,提升工作面监控视频可视化效果。

关键词：监控视频清晰化摄像仪防尘疏水图像实时去雾图像畸变校正可视化监控

How Did Poverty Reduction in China Contribute to the World? Viewing from the Implementation of the UN MDGs and SDGs

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Chinese Journal of Urban and Environmental Studies 2019年第1期7卷 118-146页

作者： gao liangliang MA Cuiping ZENG Junxia WANG Bin LI Yue Research Office for Land Economy and Human Resources Rural Development Institute Chinese Academy of Social Sciences Rural Development Institute Chinese Academy of Social Sciences Agricultural Information Institute Chinese Academy of Agricultural Sciences

Countries all over the world are highly concerned about poverty. Both the Millennium Development Goals(MDGs) and Sustainable Development Goals(SDGs) of the United Nations set ending poverty and hunger as their top priority. Whether in its own modernization drive or in the implementation of the United Nations’ MDGs and SDGs, the Chinese Government has always attached great importance to poverty issues, and actively explored measures to reduce *** paper is designed to use relevant statistics to sum up China’s achievements and experience in implementing the MDGs so as to provide a policy basis for poverty reduction in China and beyond. This paper discovers that China’s achievements in poverty reduction involve four aspects:Eliminating hunger ahead of schedule, improving people’s nutritional status, enhancing food security and laying a solid foundation for sustainable agricultural development; China’s experience in poverty reduction includes the following: the government had paid high attention; economic development had served as the key to solve all problems; the development had been guided by planning and guaranteed by policies and regulations; the market mechanism had played its due role; emphasis had been placed on the pilot projects and step-by-step promotion strategy, as well as on development cooperation and experience exchanges. The Chinese Government had formulated specific plans to achieve the poverty reduction targets set in the 2030 Agenda for Sustainable Development. Besides, the Rural Revitalization Strategy proposed by the Chinese Government in 2017 has become the essential strategy to solve the poverty-related issues in China’s development.

关键词： Millennium Development Goals (MDGs) Sustainable Development Goals (SDGs) poverty hunger China’s experience

基于机器视觉的大闸蟹自动分级分选设备研究与开发

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扬州大学学报（农业与生命科学版） 2024年第4期45卷 137-146页

作者：吴思诸定莲鲁梦瑶万以磊高亮亮陈龙汤卫荣吴文彪农芯(南京)智慧农业研究院南京211800 北京市农林科学院信息技术研究中心北京100097

为降低大闸蟹品质分级劳动成本,提高大闸蟹分级分选准确率及效率,开发一种基于机器视觉、自动称重技术的大闸蟹自动分级分选设备,利用深度学习技术获取大闸蟹公母、残缺等表型特征对大闸蟹进行品质分级。设备包含活蟹装载仓模块、自动... 详细信息

为降低大闸蟹品质分级劳动成本,提高大闸蟹分级分选准确率及效率,开发一种基于机器视觉、自动称重技术的大闸蟹自动分级分选设备,利用深度学习技术获取大闸蟹公母、残缺等表型特征对大闸蟹进行品质分级。设备包含活蟹装载仓模块、自动输送模块、图像采集模块、动态称重模块、自动分拣模块,具备自动分料、传输、品质分级功能。经试验测试,大闸蟹公母识别准确率为98.45%,残缺识别准确率为93.28%,重量识别准确率为94.68%,识别准确率和分拣效率可满足实际应用要求,稳定性良好。结果表明该设备能自动、准确地完成大闸蟹的分级分选,可为农业智能化提供技术支撑。

关键词：大闸蟹机器视觉自动称重分级分选设备

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考虑地下通道的盾构隧道下穿轨道群施工影响

甘肃科学学报 2024年第5期36卷 9-15页

作者：杨琳杰郜亮亮汤劲松陈之宁朱正国石家庄铁道大学土木工程学院河北石家庄050043

为了研究盾构隧道下穿铁路客站轨道群时,轨道下穿施工对铁路轨道几何形位的影响和地下通道的存在有何种作用,采用数值模拟的方法对盾构隧道下穿铁路旅客地下通道和客站轨道进行研究,确定轨道变形的主要分析指标,探讨了地下通道存在的作... 详细信息

为了研究盾构隧道下穿铁路客站轨道群时,轨道下穿施工对铁路轨道几何形位的影响和地下通道的存在有何种作用,采用数值模拟的方法对盾构隧道下穿铁路旅客地下通道和客站轨道进行研究,确定轨道变形的主要分析指标,探讨了地下通道存在的作用,并结合呼和浩特市轨道交通2号线的现场监测数据进行对比分析。结果表明:盾构隧道下穿铁路轨道对铁路轨道几何形位影响最大的是轨道沉降,其次为轨道高低不平顺和水平不平顺;盾构隧道正交或斜交下穿铁路时,地下通道的存在会减小轨道的变形;盾构隧道正交下穿铁路轨道时,盾构隧道轴线应距地下通道中心线3倍以上隧道直径;近距离穿过地下通道,可斜交通过,但应做好防止地下通道沉降过大的防护工作。

关键词：盾构隧道地下通道轨道几何形位轨道变形下穿施工

Fabrication of MXene-Bi_(2)WO_(6)heterojunction by Bi_(2)Ti_(2)O_(7)hinge for extraordinary LED-light-driven photocatalytic performance

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Nano Research 2024年第6期17卷 4729-4736页

作者： Zhiwen Li liangliang Xu Zaheer Ud Din Babar Ali Raza Yifei Zhang Xinrui Gu Yu-Xin Miao Zhen Zhao gao Li Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Scuola Superiore Meridionale(SSM) University of Naples Federico IILargo S.Marcellino1080138Italy Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea University of Chinese Academy of Sciences Beijing 100049China

Heterojunction composites with intimate interfaces can shorten the diffusion distance,which leads to a shorter path for photogenerated carriers,thereby increasing photocatalytic ***,we report the fabrication of Ti_(3)C_(2)-Bi_(2)WO_(6)(TC-BW)heterojunctions hinged by Bi_(2)Ti_(2)O_(7)joints via an in situ hydrothermal reaction of Ti_(3)C_(2)in the presence of Na_(2)WO_(4)and Bi(NO_(3))_(3).The TC-BW was characterized using X-ray diffraction(XRD),scanning transmission electron microscopy(STEM),and Raman ***-BW showed superior photocatalytic activity(productivity over 15TC-WB reaches up to 5.0 mmolreacted BA·gcat.^(−1)·h^(−1))in the oxidation of benzyl alcohol using light-emitting diode(LED)light,arising from the surface defects and intimate heterojunction interface between the Ti_(3)C_(2)MXene and Bi_(2)WO_(6)***-BW heterojunctions provide an enhanced separation efficiency of photogenerated charges,which in turn yields superior photocatalytic ***,it is well substantiated by density functional theory(DFT)*** summary,this study elucidates the preparation of heterojunction composites with intimate interfaces for highly efficient photooxidation.

关键词： MXene-Bi_(2)WO_(6) heterojunction LED-light-driven photocatalysis Bi_(2)Ti_(2)O_(7) photooxidation