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Temporary fluoride concentration changes in groundwater in the context of impact assessment in the Vaniyar sub-basin, South India

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Acta Geochimica 2017年第1期36卷 112-123页

作者： S. Satheeshkumar S. Venkateswaran R. Kannan Department of Geology Periyar University SalemTamil Nadu 636011 India

India＇s surface water and groundwater distribu- tion is temporally variable due to the monsoon. Agriculture is one of the dominant economic sectors in India. Groundwater quality is regularly assessed to determine usability for drinking and irrigation. In this study, World Health Organization and Bureau of Indian Standards guidelines were used to determine suitability of ground- water near artificial recharge structures （ARS） with a focus on the structureg impact on groundwater quality. Ground- water resources were evaluated for irrigation suitability using electrical conductivity （EC）, sodium adsorption ratio, the US Salinity Laboratory diagram, sodium concentration, Wilcox＇s diagram, Kelly＇s index, and Doneen＇s perme- ability index. EC and major ions were tested in recharge areas at different distances from the ARS. The construction of ARS at optimal distances along major streams has improved groundwater quantity and quality in the subbasin. Before construction of ARS, fluoride concentrations were higher; after construction, fluoride was reduced in most locations. Water stored in the check dam and groundwater in the wells closer to the structure were suitable for both drinking and irrigation purposes. Impact of ARS on nearby groundwater quality was observed at Pal- lipatti, Mulayanur, Venkadasamuthram, Pudupatti, Poyyappatti, Harurl, and Sekkampatti. More distant sites included Pappiredipatti, Nambiyappati, Menasi, Harur, Todampatti, and Adikarapatfi. data demonstrated improved groundwater quality in the area of the ARS. Through recharge, the non-potable fluoride in the region is reduced to the permissible limit for human consumption.

关键词： Drinking purposes Salinity Check dam Fluoride Dental fluorosis

A Shoreline Change Analysis Along the Coast Between Kanyakumari and Tuticorin, India, Using Digital Shoreline Analysis system

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Geo-Spatial Information Science 2011年第4期14卷 282-293页

作者： SHEIK Mujabar CHANDRASEKAR National College of Engineering Anna University of Technology Centre for Geotechnology Manonmaniam Sundaranar University

The shoreline is one of the rapidly changing landforms in coastal areas. They are the key element in coastal GIS and provide the most information on coastal land form dynamics. Therefore, accurate detection and frequent monitoring of shorelines is very essential to understand the coastal processes and dynamics of various coastal features. The present study is to investigate the shoreline changes along the coast between Kanyakumari and Tuticorin of south India （where hydrodynamic and morphologic changes occur continuously after the December 2004 tsunami） by using Digital Shoreline Analysis system （DSAS）, an extension of ArcGIS. Multidate 1RS and Landsat Satellite data （1999, 2001, 2003, 2005, 2007, and 2009） are used to extract the shorelines. The data is processed by using the ERDAS IMAGINE 9.1 software and analyzed by ArcGIS 9.2 workstation. The rates of shoreline changes are estimated by three statistical methods, namely, End Point Rate （EPR）, Linear Regression Rate （LRR）, and Least Median of Squares （LMS） by using DSAS. The study reveals that most of the study area has undergoing erosion. Both natural and anthropogenic processes along the coast modify the shoreline configuration and control the erosion and accretion of the coastal zones. The coastal zones along the estuary have experienced accretion due to the littoral processes. The zones with headlands have more eroded than other zones along the study area. The study also shows that the coastal zones where sand is mined have relatively more rate of erosion than that of the other zones. Improper and unsustainable sand mining may also lead to severe erosion problem along this area. The shoreline change rates are altered by various geological processes along the coast. Thus, the present study implies that proper beach filling and nourishment projects should be made in the study area to save from hazards. It also indicates the advantage and suitability of DSAS to assess the shoreline changes compared with the tradi

关键词： coastal zone management erosion accretion hazards beach nourishment

Scalable and adaptive log manager in distributed systems

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Frontiers of Computer Science 2023年第2期17卷 45-62页

作者： Huan ZHOU Weining QIAN Xuan ZHOU Qiwen DONG Aoying ZHOU Wenrong TAN The Key Laboratory for Computer systems of State Ethnic Affairs Commission Southwest Minzu UniversityChengdu 610041China School of data Science and Engineering East China Normal UniversityShanghai 200062China

On-line transaction processing(OLTP)systems rely on transaction logging and quorum-based consensus protocol to guarantee durability,high availability and strong *** makes the log manager a key component of distributed database management systems(DDBMSs).The leader of DDBMSs commonly adopts a centralized logging method to writing log entries into a stable storage device and uses a constant log replication strategy to periodically synchronize its state to *** the advent of new hardware and high parallelism of transaction processing,the traditional centralized design of logging limits scalability,and the constant trigger condition of replication can not always maintain optimal performance under dynamic *** this paper,we propose a new log manager named Salmo with scalable logging and adaptive replication for distributed database *** scalable logging eliminates centralized contention by utilizing a highly concurrent data structure and speedy log hole *** kernel of adaptive replication is an adaptive log shipping method,which dynamically adjusts the number of log entries transmitted between leader and followers based on the real-time *** implemented and evaluated Salmo in the open-sourced transaction processing systems Cedar and *** results show that Salmo scales well by increasing the number of working threads,improves peak throughput by 1.56×and reduces latency by more than 4×over log replication of Raft,and maintains efficient and stable performance under dynamic workloads all the time.

关键词： distributed database systems transaction log-ging log replication scalable adaptive

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Transformer architecture based on mutual attention for image-anomaly detection

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Virtual Reality & Intelligent Hardware 2023年第1期5卷 57-67页

作者： Mengting ZHANG Xiuxia TIAN Department of Computer Science and Techology Shanghai University of Electric PowerShanghai 20090China

Image-anomaly detection, which is widely used in industrial fields. Previous studies that attempted to address this problem often trained convolutional neural network-based models(e.g., autoencoders and generative adversarial networks) to reconstruct covered parts of input images and calculate the difference between the input and reconstructed images. However, convolutional operations are effective at extracting local features, making it difficult to identify larger image anomalies. Method To this end, we propose a transformer architecture based on mutual attention for image-anomaly separation. This architecture can capture long-term dependencies and fuse local and global features to facilitate better image-anomaly detection. Result Our method was extensively evaluated on several benchmarks, and experimental results showed that it improved the detection capability by 3.1% and localization capability by 1.0% compared with state-of-the-art reconstruction-based methods.

关键词： Anomaly detection Swin transformer Feature fusion Attentional mechanism Unsupervised learning

Determination of soil physicochemical attributes in farming sites through visible,near-infrared diffuse reflectance spectroscopy and PLSR modeling

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Ecological Processes 2018年第1期7卷 285-296页

作者： Amol D.Vibhute Karbhari V.Kale Suresh C.Mehrotra Rajesh K.Dhumal Ajay D.Nagne Geospatial Technology Research Laboratory Department of Computer Science and ITDr.Babasaheb Ambedkar Marathwada UniversityAurangabadMaharashtra 431004India Department of Computer Science and IT Dr.Babasaheb Ambedkar Marathwada UniversityAurangabadMaharashtra 431004India

Introduction:An accurate and reliable detection of soil physicochemical attributes(SPAs)is a difficult and complicated issue in soil *** SPA may be varied spatially and temporally with the complexity of *** the past,SPA detection has been obtained through routine soil chemical and physical laboratory ***,these laboratory methods do not fulfill the rapid ***,diffuse reflectance spectroscopy(DRS)can be used to nondestructively detect and characterize soil attributes with superior *** the present article,we report a study done through spectral curves in the visible(350–700 nm)and near-infrared(700–2500 nm)(VNIR)region of 74 soil specimens which were agglomerated by farming sectors of Phulambri Tehsil of the Aurangabad region of Maharashtra,*** quantitative analysis of VNIR spectrum was ***:The spectra of agglomerated farming soils were acquired by the Analytical Spectral Device(ASD)Field spec 4 *** soil spectra of the VNIR region were preprocessed to get pure spectra which were the input for regression *** partial least squares regression(PLSR)model was computed to construct the calibration models,which were individually validated for the prediction of SPA from the soil *** computed model was based on a correlation study between reflected spectra and detected *** detected SPAs were soil organic carbon(SOC),nitrogen(N),soil organic matter(SOM),pH values,electrical conductivity(EC),phosphorus(P),potassium(K),iron(Fe),sand,silt,and *** accuracy of the PLSR model-validated determinant(R^(2))values were SOC 0.89,N 0.68,SOM 0.93,pH values 0.82,EC 0.89,P 0.98,K 0.82,Fe 0.94,sand 0.98,silt 0.90,and clay 0.69 with root mean square error of prediction(RMSEP)3.51,4.34,2.66,2.12,4.11,1.41,4.22,1.56,1.89,1.97,and 9.91,*** to the experimental results,the VNIR-DRS was better for detection of SPA and produced more accurate predictions for ***

关键词： VNIR reflectance spectroscopy First-derivative transformation Soil physicochemical attributes Partial least squares regression(PLSR) Spectral pre-treatment Nondestructive technique Soil spectral features

Modeling and management performances of distributed energy resource for demand flexibility in Japanese zero energy house

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Building Simulation 2023年第11期16卷 2177-2192页

作者： Yanxue Li Xiaoyi Zhang Fu Xiao Weijun Gao Yan Liu Innovation Institute for Sustainable Maritime Architecture Research and Technology Qingdao University of TechnologyQingdao266033China Department of Building Environment and Energy Engineering The Hong Kong Polytechnic UniversityHong KongChina Faculty of Environmental Engineering The University of KitakyushuKitakyushu808-0135Japan

Zero-energy buildings(ZEBs)can contribute to decarbonizing building energy systems,while the energy mismatch between energy demand and on-site stochastic generation in ZEBs increases the need for energy *** study proposed mixed-integer linear programming energy management schemes for optimizing the flexible scheduling of distributed energy resources,including battery energy storage,heat pump,and building thermal mass as a passive thermal energy storage *** optimally designed objectives,this study used case studies to evaluate the flexibility potential provided by the demand-side management,considering dynamic characteristics of the *** results showed that the proposed demand-side management for battery storage offers significant potential in increasing photovoltaic(PV)self-consumption and reducing operational *** reduction ratios of flexible dispatch of combined PV and battery storage systems exceed 15%.Flexible coupling of PV and heat pump systems for meeting hot water demand can reduce energy cost by more than 20%.The flexible coupling of the heat pump and PV system also had a significant impact on the power consumption pattern of domestic heat pumps,the load-shifting potential highly depends on the available PV generation and hot water *** optimal trade-off between thermal energy use and thermal comfort violation may not reduce the total energy used for space heating,the increased PV consumption helped reduce grid *** study provides insights into the energy flexibility behavior and efficiency of the proposed demand-side management for ZEBs,which is expected to provide guidelines for exploring demand-side flexibility.

关键词： energy flexibility zero-energy building distributed energy resources energy system management

Stability and Hopf Bifurcation Analysis of a Predator-Prey Model with Time Delayed Incomplete Trophic Transfer

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 235-246页

作者： Chang-qin ZHANG Liping LIU Ping YAN Lin-zhong ZHANG School of Sciences Anhui Agricultural University Department of Mathematics Lakehead University

A new nonlinear predator-prey model with incomplete trophic transfer is introduced. In this model, we assume that the rate of the trophic absorption of the predator is less than the rate of the conversion of consumed prey to predator in the Ivlev-type functional responses. The existence and uniqueness of the positive equilibrium of the model and the stability of the equilibrium of the model are studied under various conditions. Hopf bifurcation analysis of the delayed model is provided.

关键词： incomplete trophic transfer time delay Ivlev-type existence and uniqueness stability Hopfbifurcation

Remote sensing of soil degradation:Pro gress andperspective

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International Soil and Water Conservation Research 2023年第3期11卷 429-454页

作者： Jingzhe Wang Jianing Zhen Weifang Hu Songchao Chen Ivan Lizaga Mojtaba Zeraatpisheh Xiaodong Yang School of Artificial Intelligence Shenzhen PolytechnicShenzhen518055China State Key Laboratory of resources and Environmental Information system Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China Institute of Agricultural resources and Environment Guangdong Academy of Agricultural SciencesGuangzhou510640China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou311200China Isotope Bioscience Laboratory-ISOFYS Department of Green Chemistry and TechnologyGhent UniversityCoupure Links 6539000GhentBelgium Rubenstein School of Environment and natural resources University of Vermont81 Carrigan DriveBurlingtonVT05405USA Gund Institute for Environment University of Vermont210 Colchester AveBurlingtonVT05401USA Department of Geography and Spatial Information Technology Ningbo UniversityNingbo315211China

Soils constitute one of the most critical natural resources and maintaining their health is vital for agricultural development and ecological sustainability,providing many essential ecosystem *** by climatic variations and anthropogenic activities,soil degradation has become a global issue that seriously threatens the ecological environment and food *** sensing(RS)technologies have been widely used to investigate soil degradation as it is highly efficient,time-saving,and *** review encompasses recent advances and the state-of-the-art of ground,proximal,and novel Rs techniques in soil degradation-related *** reviewed the RS-related indicators that could be used for monitoring soil degradation-related *** direct indicators(mineral composition,organic matter,surface roughness,and moisture content of soil)and indirect proxies(vegetation condition and land use/land cover change)for evaluating soil degradation were comprehensively *** results suggest that these above indicators are effective for monitoring soil degradation,however,no indicators system has been established for soil degradation monitoring to *** also discussed the RS's mechanisms,data,and methods for identifying specific soil degradation-related phenomena(e.g.,soil erosion,salinization,desertification,and contamination).We investigated the potential relations between soil degradation and Sustainable Development Goals(SDGs)and also discussed the challenges and prospective use of RS for assessing soil *** further advance and optimize technology,analysis and retrieval methods,we identify critical future research needs and directions:(1)multi-scale analysis of soil degradation;(2)availability of RS data;(3)soil degradation process modelling and prediction;(4)shared soil degradation dataset;(5)decision support systems;and(6)rehabilitation of degraded soil resource and the contribution of RS *** it is difficult to moni

关键词： Soil degradation Remote sensing Soil properties Earth observation Sustainable development goals

Iteration convergence condition modeling for single spaceborne SAR image direct positioning

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Geo-Spatial Information Science 2016年第4期19卷 278-284页

作者： Yuting Dong Lu Zhang Mingsheng Liao State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing(LIESMARS)Wuhan UniversityWuhanChina Collaborative Innovation Center for Geospatial Technology Wuhan UniversityWuhanChina

Single SAR image direct positioning is to determine the ground coordinate for each pixel in the SAR image assisted with a reference *** this procedure,an iterative procedure is essentially needed to solve the uncertainty in elevation of each pixel in the SAR ***,such an iterative procedure may suffer from the problem of divergence in shaded and serious layover *** investigate this problem,we performed a theoretical analysis on the convergence conditions that has not been intensively studied till *** Range-Doppler(RD)model was simplified and then the general surface is degenerated into a planar *** deduction was then carried out to derive the convergence conditions and the impact factors for the convergence speed were *** theoretical findings were validated by experiments for both simulated and real scenarios.

关键词： Direct positioning RD model SAR iteration convergence condition