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The first all-season sample set for mapping global land cover with Landsat-8 data

Science Bulletin 2017年第7期62卷 508-515页

作者： Congcong Li Peng Gong Jie Wang Zhiliang Zhu Gregory S. Biging Cui Yuan Tengyun Hu Haiying Zhang Qi Wang Xuecao Li Xiaoxuan Liu Yidi Xu Jing Guo Caixia Liu Kwame O. Hackman Meinan Zhang Yuqi Cheng Le Yu Jun Yang Huabing Huang Nicholas Clinton Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System Science Tsinghua University Beijing 100084 China Department of environmental Science Policy and Management University of California Berkeley. CA 94720-3J 14 USA Joint Center for Global Change Studies Beijing 100875 China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Beijing 100101 China United States Geological Survey Restan VA 20192 USA Ministry of Education Key Laboratory for Geospatial Technology for the Middle and Lower Yellow River Regions College of Environment and Planning Henan University Kaifeng 475004 China Googie Inc. 1600 Amphitheatre Pkwy. Mountain View CA 94042 USA

We report the world's first all-season training and validation sample sets for global land cover classification with Landsat-8 *** to this,such samples were only available at a single date primarily from the growing *** is unknown how much limitation such a single-date sample has to mapping global land cover in other seasons of the *** answer this question,we selected available Landsat-8 images from four seasons and collected training and validation samples from *** compared the performances of training samples in different seasons using Random Forest *** found that the use of training samples from any individual season would result in the best overall classification accuracy when validated by samples in the same *** global overall accuracy from combined best seasonal results was 67.2% when classifying the 11 Level-1 classes in the Finer Resolution Observation and Monitoring of Global Land Cover(FROM-GLC) classification *** use of training samples from all seasons(named all-season training sample set hereafter) produced an overall accuracy of 67.0%.We also tested classification within 10° latitude 60° longitude zones using all-season training subsample within each zone and obtained an overall accuracy of 70.2%.This indicates that properly grouped subsamples in space can help improve classification *** the results in this study seem to suggest that it is possible to use an all-season training sample set to reach global optimality with universal applicability in classifying images acquired at any time of a year for global land cover mapping.

关键词： Training sample Validation Latitudinal zones Anytime Anywhere

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Pollution Characteristics and Ecological Impact of Screening Analysis of Fishing Port Sediments from Dalian,North China

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Environment & health 2024年第10期2卷 702-711页

作者： Haichao Mu Xulin Hou Zilan Wu Jiaojiao Li Wenwen Wang Meiling Lu Xing Liu Ziwei Yao Key Laboratory for Ecological Environment in Coastal Areas Ministry of Ecology and EnvironmentNational Marine Environmental Monitoring CenterDalian 116023China School of Light Industry and Chemical Engineering Dalian Polytechnic UniversityDalian 116034China College of Marine Science and Environment Engineering Dalian Ocean UniversityDalian 116023China Agilent Technologies(China)Ltd. Inc.Beijing 100102China Laboratory for Ecological Environment in Coastal Areas Ministry of Ecology and EnvironmentNational Marine Environmental Monitoring CenterDalian 116023China

environmental pollution from synthetic chemical mixtures has significant adverse impacts on marine ***,identifying the main constituents of chemical mixtures that pose ecological threats is challenging due to the necessity of an integrated workflow for comprehensive identification and toxicological prioritization of ***,an all-in-one mass spectrometric strategy integrating target,suspect,and nontarget analysis was used to investigate organic pollutants of concern in fishing port sediments,with 355 pollutants(32 from target analysis,118 from suspect screening and 205 from nontarget analysis)identified in 11 *** chemical classes of polycyclic aromatic hydrocarbons(PAHs),pesticides,and intermediates were the extensively detected chemical *** ecological risks of absolutely quantified pollutants(i.e.,16 parent PAHs,7 organophosphate esters(OPEs),10 pesticides and 4 benzotriazole ultraviolet absorbers)were assessed using toxicity-weighted concentration ranking,with o,p’-DDT being the major *** the toxicological priority index(ToxPi)framework,an extended ranking of all identified pollutants was achieved by combining instrument response and detection frequency,with a priority control list of 15 pollutants obtained,of which benzo[ghi]perylene(BghiP)and p,p’-DDE had the highest risk *** to frequent detection rates and significant environmental risks,routine monitoring of petroleum pollutants is considered *** study presents a general workflow that inc.udes comprehensive identification and prioritization of pollutants,facilitating chemical management and ecological risk assessment.

关键词： fishing port sediments suspect screening nontarget analysis toxicity-weighted concentration ToxPi ecological risk assessment

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土壤的冷生构造及其对阿拉斯加土地利用的意义(英文)

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冰川冻土 2004年第S1期26卷 1-7页

作者： C.L Ping M.T. Jorgeson Y.L. Shur Agricultural and Forestry Experiment Station University of Alaska Fairbanks Palmer AK 99645 USAABR Inc. Fairbanks AK USADepartment of Civil and Environmental Engineering University of Alaska Fairbanks Fairbanks AK USA

Cryogenic structure (patterns made by ice inc.usions) in seasonally frozen and permafrost-affected soils result from ice formation during freezing. Analysis of cryogenic structures in soils is essential to our understanding of the cryogenic processes in soils and to formulating land use management interpretations. When soils freeze, the freezing front moves downward and attracts water moving upward resulting in mainly horizontal lenticular ice formation. Platy and lenticular soil structures form between ice lenses in upper active layer. The reticular soil structure usually forms above the permafrost table caused by freeze-back of the permafrost. The upward freeze-back resulted in platy soil structure and the volume changes following the annual freeze-thaw cycle resulted in vertical cracks. The combined result is an ice-net formation with mineral soils embedded in the ice net. The upper permafrost layer that used to be a part of the active layer has an ice content exceeding 50% due to repeated freeze-thaw cycles over time. The mineral soils appear in blocks embedded in an ice matrix. The permafrost layer that never experienced the freeze-thaw cycle often consists of alternate layers of thin ice lens and frozen soils with extreme hard consistence and has relatively lower ice content than the ice-rich layer of the upper permafrost. Ice contents and thaw settling potentials associated with each cryogenic structure should be considered in engineering and land use interpretations.

关键词： cryogenic structure cryogenic processes in soils ice layer land use Alaska

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Integrating the ISO 14034 standard as a platform for carbon capture and utilization technology performance evaluation

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Clean Energy 2021年第4期5卷 600-610页

作者： Tim Hansen Kevin McCabe Bill Chatterton Michael Leitch 350Solutions Inc.1053 E.Whitaker Mill RdSuite 115RaleighNC 27604USA XPRIZE Foundation 800 Corporate PointeSuite 350Culver CityCA 90230USA

Independent testing and verification of emerging technologies are vital parts of the technology-commercialization *** the rapid development of carbon capture and utilization(CCU)technologies,where existing standards and certifications do not exist,independent verification approaches and guidelines can provide a means to obtain credible information for an emerging *** ISO 14034:2016-environmental management:environmental Technology Verification(ETV)standard can serve as a foundational platform to ensure the consistency,quality and credibility of data on CCU technology performance,enabling direct comparisons between technologies and reducing risk to decision-makers regarding potential investment,future deployment and ultimate impacts of CCU *** the fundamental princ.ples of ISO 14034 to the evaluation of nine finalist CCU technologies competing in the NRG COSIA Carbon XPRIZE ensured that data used to evaluate competitors was of high quality,consistent across technologies and met the information needs of the XPRIZE and competition judges responsible for selecting *** approaches outlined here,inc.uding verification parameters and verification tasks for both XPRIZE-specific technology evaluations and full CCU technology evaluation by an accredited entity in conformance with the ISO 14034 standard,provide insight into the potential benefits-methodological consistency,high-quality data,independent oversight,methodological flexibility and broad applicability-and limitations-technology readiness and applicability,verification and instrumentation costs and lack of specificity-of the approach in an application for the evaluation of emerging *** application of the ISO 14034 standard and princ.ples,developed through a consensus approach that inc.rporates other developing guidelines,can drive consistency and credibility for technology-performance evaluations across the CCU sector,ultimately leading to reduced risk and impr

关键词： carbon capture CCUS chemical engineering coal energy and environment fossil energy

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Mobility and social deprivation on primary care utilisation among paediatric patients with asthma

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Family Medicine and Community health 2021年第3期9卷 47-53页

作者： Jennifer A Lucas Miguel Marino Sophia Giebultowicz Katie Fankhauser Shakira F Suglia Steffani R Bailey Andrew Bazemore John Heintzman Department of Family Medicine Oregon Health&Science UniversityPortlandOregonUSA OCHIN inc PortlandOregonUSA Department of Epidemiology Rollins School of Public HealthEmory UniversityAtlantaGeorgiaUSA American Board of Family Medicine LexingtonKentuckyUSA Center for Professionalism&Value in health Care WashingtonDCUSA

Objective Asthma care is negatively impacted by neighbourhood social and environmental factors,and moving is associated with undesirable asthma ***,little is known about how movement into and living in areas of high deprivation relate to primary care *** examined associations between neighbourhood characteristics,mobility and primary care utilisation of children with asthma to explore the relevance of these social factors in a primary care *** In this cohort study,we conducted negative binomial regression to examine the rates of primary care visits and annual influenza vaccination and logistic regression to study receipt of pneumococcal *** models were adjusted for patient-level *** We used data from community health centres in 15 OCHIN *** The sample inc.uded 23773 children with asthma aged 3-17 across neighbourhoods with different levels of social deprivation from 2012 to *** conducted negative binomial regression to examine the rates of primary care visits and annual influenza vaccination and logistic regression to study receipt of pneumococcal *** models were adjusted for patient-level *** Clinic visit rates were higher among children living in or moving to areas with higher deprivation than those living in areas with low deprivation(rate ratio(RR)1.09,95%CI 1.02 to 1.17;RR 1.05,95%CI 1.00 to 1.11).Children moving across neighbourhoods with similarly high levels of deprivation had inc.eased RRs of influenza vaccination(RR 1.13,95%CI 1.03 to 1.23)than those who moved but stayed in neighbourhoods of low *** Movement into and living within areas of high deprivation is associated with more primary care use,and presumably greater opportunity to reduce undesirable asthma *** results highlight the need to attend to patient movement in primary care visits,and inc.ease neighbourhood-targeted population management to improve equity and care f

关键词： deprivation asthma vaccination

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Nitrogen regulation by natural systems in“unnatural”landscapes:denitrification in ultra-urban coastal ecosystems

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Ecosystem health and Sustainability 2018年第9期4卷 17-37页

作者： Bernice R.Rosenzweig Peter M.Groffman Chester B.Zarnoch Brett F.Branco Ellen K.Hartig James Fitzpatrick Helen M.Forgione Adam Parris environmental Sciences Initiative Advanced Science Research Center at the Graduate CenterCity University of New YorkNew YorkNYUSA Earth and environmental Sciences Brooklyn CollegeCity University of New YorkBrooklynNYUSA Cary Institute of Ecosystem Studies MillbrookNYUSA Natural Sciences Baruch College and Graduate CenterCity University of New YorkNew YorkNYUSA New York City Department of Parks and Recreation Natural Resources GroupNew YorkNYUSA HDR Inc.New YorkNYUSA The Natural Areas Conservancy New YorkNYUSA Science and Resilience Institute at Jamaica Bay BrooklynNYUSA

Dense cities represent biogeochemical hot spots along the shoreline,concentrating fixed nitrogen that is subsequently discharged into adjacent coastal receiving ***,the ecosystem services provided by natural systems in highly urban environments can play a particularly important role in the global nitrogen *** this paper,we review the recent literature on nitrogen regulation by temperate coastal ecosystems,with a focus on how the distinc. physical and biogeochemical features of the urban landscape can affect the provision of this ecosystem *** use Jamaica Bay,an ultra-urbanized coastal lagoon in the United States of America,as a demonstrative case *** on simple areal and tidal-based calculations,the natural systems of Jamaica Bay remove~24%of the reactive nitrogen discharged by wastewater treatment ***,this estimate does not represent the dynamic nature of urban nitrogen cycling represented in the recent literature and highlights key research needs and *** review reveals that ecosystem-facilitated denitrification may be significant in even the most densely urbanized coastal landscapes,but critical uncertainties currently limit inc.rporation of this ecosystem service in environmental management.

关键词： Nitrogen denitrification urban coastal anammox wetlands

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Multi-Objective Optimization of Low Impact Development Designs in an Urbanizing Watershed

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Open Journal of Optimization 2013年第4期2卷 95-108页

作者： Guoshun Zhang James M. Hamlett Patrick Reed Yong Tang Bechtel Co. Houston USA Department of Agricultural and Biological Engineering Pennsylvania State University University Park USA Department of Civil and environmental Engineering Pennsylvania State University University Park USA Tetra Tech Inc. Fairfax USA

Multi-objective optimization linked with an urban stormwater model is used in this study to identify cost-effective low impact development (LID) implementation designs for small urbanizing watersheds. The epsilon-Non-Dominated Sorting Genetic Algorithm II (ε-NSGAII) has been coupled with the US environmental Protection Agency’s Stormwater management Model (SWMM) to balance the costs and the hydrologic benefits of candidate LID solutions. Our objective in this study is to identify the near-optimal tradeoff between the total LID costs and the total watershed runoff volume constrained by pre-development peak flow rates. This study contributes a detailed analysis of the costs and benefits associated with the use of green roofs, porous pavement, and bioretention basins within a small urbanizing watershed inState College,Pennsylvania. Beyond multi-objective analysis, this paper also contributes improved SWMM representations of LID alternatives and demonstrates their usefulness for screening alternative site layouts for LID technologies.

关键词： Multi-Objective Optimization ε-NSGAII Low Impact Development SWMM Stormwater

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Runoff management, Wetland Hydrology, and Biodiversity Relations in Minnesota＇s Red River Basin Wetlands

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Journal of environmental Science and Engineering(A) 2012年第1期1卷 107-124页

作者： StevenI．Apfelbaum John. D. Eppicht James A. Solstada Applied Ecological Services Inc. Chairman/Founder and Senior Ecologist Wisconsin 53520 USA Waterflow Consultants Environmental Engineer Illinois 61820 USA Minnesota Department of Natural Resources Division of Waters Technical Analysis Program Hydrologist Minnesota 55155USA

The authors assessed if wetlands can contribute to flood damage reduction in the Red River Basin, Minnesota, by providing reliable flood water storage. Hydrology and biodiversity in 28 natural and restored wetlands suggested uncontrolled natural wetlands provided the highest mean annual flood storage at 15 cm of runoff while single and 2-stage outlet controlled wetlands provided 3.0 and 8.1 cm of runoff control. Natural controlled wetlands, followed by 2-stage and single stage outlet controlled restorations provided 10.2, 6.6, and 2.2 cm of storage for early summer storm events. Two years of recorded water levels and a 20-year continuous meteorological record were used to model ＂temporary water level inc.eases＂ in each wetland. Species diversity, hydrology, and watershed land use variables are inversely related where high quality and diverse wetlands had the lowest amplitude and frequency of water level inc.eases, while low quality wetlands had the highest. Uncontrolled natural wetlands had the highest biological diversity and the lowest frequency and magnitude of temporary water levels inc.eased. A significant biodiversity declines were measured where water level inc.eases were greater than 2.7 meters. Strong multi-linear relationships between watershed land uses and watershed/wetland ratio explained wetland hydraulic performance and biodiversity relations （r2 ranging from 0.6-0.8）. Non-native wetland plant diversity inc.eased with greater water level dynamics.

关键词： Diversity and hydrology floodwater in wetlands water level dynamics.

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Poisson Process and Its Application to the Storm Water Overflows

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Computational Water, Energy, and environmental Engineering 2016年第2期5卷 47-53页

作者： Malick Baldeh Chris Samba Kenneth Tuffour Assane Boya Facility Solution Technology Inc. Bakau The Gambia Gaston Berger University Saint-Louis Senegal

The homogenous Poisson process is often used to describe the event arrivals. Such Poisson process has been applied in various areas. This study focuses on the arrival pattern of storm water overflows. A set of overflow data was obtained from the storm water pipeline of a municipality. The aim is to verify the overflow arrival pattern and check whether the Poisson process can be applied. The adopted method is the analysis over the inter-arrival times. The exponential distribution test is conducted on the annual data set as well as the entire data set. The results show that all data sets follow the exponential distribution. With the verification of Poisson process, specific examples are also given to show how the Poisson process properties can be used in the management of storm water pipeline management. For other data that are featured with various heterogeneities, the homogenous Poisson process might not be able to be verified and used. Under such circumstances, non-homogenous survival model can be used to simulate the arrival process.

关键词： Storm Water Overflow Poisson Process Exponential Distribution Weibull Distribution

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The Evolution of Reliability and Efficiency of Aerospace Bearing Systems

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Engineering（科研） 2017年第11期9卷 962-991页

作者： Peter Gloeckner Charles Rodway FAG Aerospace GmbH & Co. KG Schweinfurt Germany FAG Aerospace inc. Stratford Canada

The worldwide air traffic underwent a rapid development in recent decades.?Between the early 70s and the late 90s of the last century civil air traffic?doubled every 15 years. The civil aviation market will continue to grow with 4% - 5%?each year within the next 20 years. This enormous growth represents major?challenges for airframers, engine makers, suppliers, airlines, air traffic management?and ground infrastructure. In addition, the public debate on the worldwide?civil air traffic is dominated by environmental and climate issues, even though only 2% of the man-made carbon dioxide (CO2) emissions are due to air transportation. Therefore the aerospace industry will have to focus on a low-emission and quite air traffic, and on the conservation of natural resources and our environment. The end-use consumer and environmental policy requirements?for aircrafts of the next generation translate into components with improved efficiency and reliability. Rolling bearings are one of these components which?significantly determine the reliability and mechanical efficiency of aerospace applications such as aircraft and rotorcraft engines and transmission systems.?They have to withstand very demanding operating conditions. Especially main shaft?bearings in modern aircraft engines experience high rotational speeds andtemperatures. Furthermore aerospace bearings have to meet the highest reliability?standards and require low-weight design solutions. These operating conditions?and requirements present a continuous challenge for improvements in all?fields of bearing technology. This article presents solutions in aspects of materials, design, analysis, and surface technologies in order to meet the environmental, reliability, and economical requirements of advanced aerospace bearing systems. State of the art bearing analysis and advanced bearing design solutions?contributing to lower friction power losses and inc.eased systems efficiency?are discussed. Weight, functional, and maintenan

关键词： Rolling Element Bearings Aviation Environment Friction Efficiency Aircraft Engines Helicopter

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