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Analyzing the spatiotemporal evolution and driving forces of gross ecosystem product in the upper reaches of the Chaobai River Basin

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Frontiers of Environmental Science & engineering 2024年第8期18卷 117-132页

作者： Jiacheng Li Qi Han Liqiu Zhang Li Feng Guihuan Liu Beijing Key Laboratory for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Center of Eco-compensation Chinese Academy of Environmental PlanningMinistry of Ecology of EnvironmentBeijing 100041China

The Chaobai River Basin,which is a crucial ecological barrier and primary water source area within the Beijing-Tianjin-Hebei region,possesses substantial ecological *** gross ecosystem product(GEP)in the Chaobai River Basin is a reflection of ecosystem conditions and quantifies nature’s contributions to humanity,which provides a basis for basin ecosystem service management and *** study investigated the spatiotemporal evolution of GEP in the upper Chaobai River Basin and explored the driving factors influencing GEP spatial *** patterns from 2005 to 2020 were analyzed,and GEP was calculated for 2005,2010,2015,and *** driving factors influencing GEP spatial differentiation were identified using the optimal parameter-based geographical detector(OPGD)*** key findings are as follows:(1)From 2005 to 2020,the main ecosystem types were forest,grassland,and *** areas experienced significant changes,and conversions mainly occurred among urban,water,grassland and agricultural ecosystems.(2)Temporally,the GEP in the basin increased from 2005 to 2020,with regulation services *** the county(district)scale,GEP exhibited a north-west-high and south-east-low pattern,showing spatial differences between per-unit-area GEP and county(district)GEP,while the spatial variations in per capita GEP and county(district)GEP were similar.(3)Differences in the spatial distribution of GEP were influenced by regional natural geographical and socioeconomic *** these factors,gross domestic product,population density,and land-use degree density contributed *** among different driving forces noticeably impacted GEP spatial *** findings underscore the necessity of incorporating factors such as population density and the intensity of land-use development into ecosystem management decision-making processes in the upper reaches of the Chaobai River *** policies

关键词： Ecosystem pattern Gross ecosystem product(GEP) Spatiotemporal evolution Optimal parameter-based geographical detector(OPGD) Chaobai River Basin

Biochemistry and transcriptome analysis reveal condensed tannins alleviate liver injury induced by regulating cholesterol metabolism pathway

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Food Science and Human Wellness 2024年第2期13卷 909-919页

作者： Xiangxin Li Yijing Pu Bangdi Liu Xiaoming Fang Wenjun Peng Weibo Jiang Wenli Tian Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China college of Food Science and Nutritional engineering China Agricultural UniversityBeijing 100083China Academy of Agricultural planning and engineering Ministry of Agriculture and Rural AffairsBeijing 100125China

Free cholesterol has been considered to be a critical risk factor of nonalcoholic fatty liver disease(NAFLD).It remains unknown whether dietary intake of condensed tannins(CTs)have distinguishable effects to alleviate liver damage caused by a high cholesterol *** C57BL/6 mice were fed a high cholesterol diet for 6 weeks,and given CTs treatment at a dosage of 200 mg/(kg·day)at the same *** results indicated that compared with mice fed a normal diet,a high cholesterol diet group resulted in significant weight loss,dysregulation of lipid metabolism in blood and liver,and oxidative stress in the liver,but CTs treatment dramatically reversed these negative *** and eosin(H&E)staining and frozen section observation manifested that CTs treatment could effectively reduce the deposition of liver cholesterol and tissue necrosis caused by high cholesterol *** alleviated liver injury mainly by regulating the expression of related genes in cholesterol metabolism pathway and AMPK *** results confirmed that CTs have remarkable cholesterol lowering and anti-liver injury effects in vivo.

关键词： Condensed tannins High cholesterol Liver injury Antioxidants Transcriptomic analysis

Status and trends of carbon emissions research at the county level in China

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Advances in Climate Change Research 2024年第2期15卷 338-352页

作者： Ang-Zu CAI Ru GUO Yu-Hao ZHANG Jiang WU college of Environmental Science and engineering Institute of Environmental Planning and ManagementTongji UniversityShanghai 200092China Institute of Carbon Neutrality Tongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China college of Architecture and Urban planning Tongji UniversityShanghai 200092China Megacity Elaborated Urban Governance Institute Tongji UniversityShanghai 200092China

This study provides a comprehensive overview of the challenges to achieving carbon neutrality at the county level in China and offers targeted recommendations,laying the groundwork for future specialized research in this area.A total of 283 relevant studies(2004-2023)were analyzed to assess county-level carbon emissions through three phases:bibliometric analysis,frontier analysis,and future *** findings reveal that publication trends were largely influenced by domestic and foreign *** cluster discerns ten primary themes,ranging from conceptual frameworks to research *** frontier analysis of the literature highlights the leading research areas,which include carbon neutrality pathway,driving factors,spatiotemporal variation of carbon emissions,the co-effects of pollutants and carbon reduction,and carbon emissions in China's rural *** from the results of bibliometric and frontier analyses,this study elucidates the recommendations for achieving carbon neutrality at the county level from three perspectives:effective regional policy guidance,emphasis on ecological conservation,and the deployment of advanced carbon reduction and sequestration *** study enriches the body of knowledge on carbon emissions at the county level and holds significant implications for China's comprehensive push towards achieving its carbon neutrality objectives.

关键词： Carbon emissions Emission reduction County Carbon neutrality Sustainability

Formation adaptation in obstacle-cluttered environments via MPC-based trajectory planning

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Science China(Information Sciences) 2024年第7期67卷 321-323页

作者： Yuda CHEN Zhongkui LI Department of Mechanics and engineering Science College of Engineering Peking University

Formation is a typical collective behavior in multiagent systems utilized in areas such as inspection, surveillance, and transportation. Commonly-used approaches to achieve formation include virtual structure [1], con...

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Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network

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Journal of Systems engineering and Electronics 2024年第2期35卷 495-508页

作者： YANG Luyi LI Haiyang ZHANG Jin ZHU Yuehe college of Aerospace Science and engineering National University of Defense TechnologyChangsha 410073China China Astronauts Research and Training Center Beijing 100094China Hunan Key Laboratory of Intelligent planning and Simulation for Aerospace Missions Changsha 410073China

It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.

关键词： manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency

Proposing a development framework for sustainable architecture, engineering, and construction industry in China: Challenges, best practice, and future directions

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Frontiers of Structural and Civil engineering 2024年第5期18卷 805-814页

作者： Peixian LI Yujie LU Xuwen XIAO college of Architecture and Urban planning Tongji UniversityShanghai 200092China Key Laboratory of Ecology and Energy Saving Study of Dense Habitat(Tongji University) Ministry of EducationShanghai 200092China college of Civil engineering Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for engineering Structures of Ministry of Education Tongji UniversityShanghai 200092China China State Construction engineering Corporation Beijing 100029China

China’s architecture,engineering,and construction(AEC)industry needs a clear and sustainable development *** inspiration from speeches delivered at a seminar hosted by the Chinese Academy of engineering and extensive literature research on Chinese policies,this article presents a summary of the current trends in the AEC industry in four dimensions:industrialization as the foundation,intelligence as the enabler,lean management as the strategy,and green development as the *** four dimensions are intricately interconnected and rooted in multiple *** article provides a detailed review of the current practices,challenges,and future directions associated with each ***,ten grand challenges were proposed to stimulate discussions on the future of the AEC *** article offers an overarching understanding of the AEC industry and presents a four-dimension framework for sustainable development,which can be valuable for AEC practitioners.

关键词： green building lean construction prefabrication smart construction sustainable development

Experimental research on the microclimate in the naturally ventilated multi-span greenhouse

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International Journal of Agricultural and Biological engineering 2024年第3期17卷 68-74页

作者： Zhenjun Gao Wenyang Li Wei Li Xiaoming Ding college of Mechanical and Power engineering China Three Gorges UniversityYichang 443002HubeiChina Guangdong Modern Agricultural Equipment Research Institute Guangzhou 510630China Key Laboratory of Agricultural Facilities Structural engineering Academy of Agricultural Planning and EngineeringMinistry of Agriculture and Rural AffairsBeijing 100125China

In order to further understand the changing laws of environmental factors in large multi-span greenhouses under natural ventilation conditions and the internal relations between various environmental factors,and ultimately improve the precision of microclimate regulation of large multi-span *** the multi-span greenhouse with a small spire structure in the Demonstration Base of Guangdong Agricultural Technology Extension Station as the research object,under the condition of natural ventilation with butterfly-shaped windows,the changes in temperature,humidity,wind speed and solar light intensity of different monitoring planes in the greenhouse were *** analyzing the monitoring data,it was found that:1)The temperature gradient in the vertical direction in the large multi-span greenhouse is more obvious than that in the small greenhouse,and the highest average temperature difference monitored can reach 7.9℃.The velocity field in the multispan greenhouse is always maintained within the range of 0.3-0.4 m/s,and the ambient wind speed has no effect on the airflow speed in the *** humidity and speed in the multi-span greenhouse show good uniformity.2)In a large multi-span greenhouse,the secondary radiation generated by the internal shading has less impact on the area near the ground,which can effectively reduce the ground temperature.3)Under the conditions studied in this research,the temperature and humidity in the greenhouse follow the external environment as well,showing that the greenhouse design is reasonable,and the air renewal and heat exchange inside and outside the greenhouse are good during natural ventilation.

关键词： natural ventilation multi-span greenhouse environmental factors microclimate

A theoretical study on gaseous pollutant flushing of natural ventilation driven by buoyancy forces in industrial buildings

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Building Simulation 2024年第4期17卷 575-589页

作者： Jiawei Zhuang Genyang Chen Rumeng Yang Kun Han Dongdong Tian Yongfa Diao Henggen Shen School of Urban Construction Changzhou UniversityChangzhou213164China School of Petroleum and Natural Gas engineering School of EnergyChangzhou UniversityChangzhou213164China college of Environmental Science and engineering Donghua UniversityShanghai201620China School of Architecture and Urban planning Nanjing UniversityNanjing210093China

The acceleration of industrialization worsening indoor environments of industrial buildings has drawn more attention in recent *** ventilation can improve indoor air quality(IAQ)and reduce carbon *** evaluate gaseous pollutant levels in industrial buildings for the development of buoyancy-driven natural ventilation,two theoretical models of pollutant flushing(Model I and Model II)are developed based on the existing thermal stratification theory in combination with the mixing characteristics of lower *** results show that indoor pollutant flushing is mainly dependent on the pollution source intensity and effective ventilation *** mixing characteristics of lower pollutant has an important effect on pollutant stratification and evolution during ventilation,but it does not change the prediction results at steady *** the dimensionless pollution source intensity is larger than 1,the pollution source should be cleaned up or other ventilation methods should be used instead to improve *** addition,the comparisons between Model I and Model II on instantaneous pollutant concentration are significantly influenced by the pollution source intensity,and the actual pollutant concentration is more likely to be between the predicted values of Model I and Model *** reduce pollutant concentration to a required level,the pollution source intensity should be in a certain *** theoretical models as well as the necessary conditions for ventilation effectiveness obtained can be used for the ventilation optimization design of industrial buildings.

关键词： industrial buildings buoyancy-driven natural ventilation gaseous pollutants evolution model pollution sources

Online task planning method of anti-ship missile based on rolling optimization

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Journal of Systems engineering and Electronics 2024年第3期35卷 720-731页

作者： LU Faxing DAI Qiuyang YANG Guang JIA Zhengrong college of Weaponry engineering Naval University of EngineeringWuhan 430033China

Based on the wave attack task planning method in static complex environment and the rolling optimization framework, an online task planning method in dynamic complex environment based on rolling optimization is proposed. In the process of online task planning in dynamic complex environment,online task planning is based on event triggering including target information update event, new target addition event, target failure event, weapon failure event, etc., and the methods include defense area reanalysis, parameter space update, and mission re-planning. Simulation is conducted for different events and the result shows that the index value of the attack scenario after re-planning is better than that before re-planning and according to the probability distribution of statistical simulation method, the index value distribution after re-planning is obviously in the region of high index value, and the index value gap before and after re-planning is related to the degree of posture change.

关键词： target allocation of anti-ship missile defense area rolling optimization task re-planning