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Assessing the Economic Value of Improvement in Water Quality and Aquatic Ecosystem Services Resulting from Ecological Stream Restoration in South Korea
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作者 Hyun No Kim Hwanhee Ryu 《Journal of Environmental & Earth Sciences》 2025年第1期471-484,共14页
Urbanization and environmental degradation have led to significant declines in water quality and aquatic ecosystem health,highlighting the urgent need for effective restoration efforts.This study applies an integrated... Urbanization and environmental degradation have led to significant declines in water quality and aquatic ecosystem health,highlighting the urgent need for effective restoration efforts.This study applies an integrated analysis approach to estimate the economic value and benefits of improvements in water quality and aquatic ecosystem services resulting from the Ecological Stream Restoration Project.Using survey data analyzed through the choice experiment(CE)method,we assessed respondents’preferences for various ecosystem services,including water-friendly services,ecological functions,water-level control,and water-quality purification.Three empirical analysis models—the Conditional Logit Model(CLM),Nested Logit Model(NL),and Error Component Logit Model(ECL)—were applied,with the ECL model identified as the most suitable for this study.From the physical impact assessment,we derived compensating variations to estimate the annual economic benefits of the project.The estimated annual economic value of water quality improvement due to the Anyangcheon Ecological Stream Restoration Project ranged from approximately KRW 10.54 billion to KRW 21.44 billion,while the economic value of aquatic ecosystem improvement was estimated to range from KRW 6.05 billion to KRW 12.30 billion annually.This study provides analytic framework that can inform future ecological restoration projects and sustainable water management policies. 展开更多
关键词 Ecological stream Restoration Non-Market Valuation Choice Experiment Ecosystem Services Integrated Environmental And Economic Analysis
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Secure task offloading strategy optimization of UAV-aided outdoor mobile high-definition live streaming
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作者 Ming YAN Yuxuan ZHANG +2 位作者 Chien Aun CHAN André F.GYGAX Chunguo LI 《Chinese Journal of Aeronautics》 2025年第10期201-215,共15页
Unmanned aerial vehicles(UAVs)bring more innovation and attraction to outdoor mobile high-definition(HD)live streaming with its unique perspective.Due to the heavy computational requirements of HD live broadcast tasks... Unmanned aerial vehicles(UAVs)bring more innovation and attraction to outdoor mobile high-definition(HD)live streaming with its unique perspective.Due to the heavy computational requirements of HD live broadcast tasks and the limited hardware performance of UAV equipment,how to reduce the system response delay and improve the energy efficiency of terminal equipment directly affects the secure broadcast of the system.Secure task offloading in this scenario is considered a promising solution and has received academic attention.In this paper,we simulate the UAV-aided outdoor mobile HD live streaming scenarios and optimize the relevant task offloading strategies.First,we design the total cost function of task offloading that jointly optimizes secure time latency and energy consumption.Additionally,we propose a collaborative computing model for multi-UAV task offloading.This model combines the idea of simulated annealing(SA)and introduces the compression factor to enhance the particle swarm optimization(PSO)to realize secure task offloading.The simulation results show that the proposed strategy has better performance in balancing network latency and energy consumption.Compared with the discrete teaching–learning-based optimization(DTLBO)and quantum PSO(QPSO)task offloading strategies,the fitness value of the proposed strategy is decreased by an average of 26.73%and 16.42%,respectively. 展开更多
关键词 Unmanned aerial vehicle(UAV) High-definition(HD)live streaming Secure task offloading Network energy consumption Particle swarm optimization(PSO)
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EGOP: A Server-Side Enhanced Architecture to Eliminate End-to-End Latency Caused by GOP Length in Live Streaming
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作者 Kunpeng Zhou Tao Wu Jia Zhang 《Computers, Materials & Continua》 2026年第1期935-961,共27页
Over the past few years,video live streaming has gained immense popularity as a leading internet application.In current solutions offered by cloud service providers,the Group of Pictures(GOP)length of the video source... Over the past few years,video live streaming has gained immense popularity as a leading internet application.In current solutions offered by cloud service providers,the Group of Pictures(GOP)length of the video source often significantly impacts end-to-end(E2E)latency.However,designing an optimized GOP structure to reduce this effect remains a significant challenge.This paper presents two key contributions.First,it explores how the GOP length at the video source influences E2E latency in mainstream cloud streaming services.Experimental results reveal that the mean E2E latency increases linearly with longer GOP lengths.Second,this paper proposes EGOP(an Enhanced GOP structure)that can be implemented in streaming media servers.Experiments demonstrate that EGOP maintains a consistent E2E latency,unaffected by the GOP length of the video source.Specifically,even with a GOP length of 10 s,the E2E latency remains at 1.35 s,achieving a reduction of 6.98 s compared to Volcano-Engine(the live streaming service provider for TikTok).This makes EGOP a promising solution for low-latency live streaming. 展开更多
关键词 GOP EGOP low-latency live streaming TikTok
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Spatial and temporal variability of agricultural pollutants in an agricultural headwater stream within a multipond system, southeastern China 被引量:2
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作者 MAOZhan-po YINCheng-qing SHANBao-qing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期697-704,共8页
The spatial and temporal variability of nutrients and suspended solids were investigated for two years in a 1.8 km agricultural headwater stream, located by Chaohu Lake, southeastern China. The stream form was greatly... The spatial and temporal variability of nutrients and suspended solids were investigated for two years in a 1.8 km agricultural headwater stream, located by Chaohu Lake, southeastern China. The stream form was greatly modified by human activities into channelized, pond and estuary shapes. The stream could be divided into 4 channelized reaches(1.3 km), a pond reach(0.15 km) and 3 estuary reaches(0.36 km). It was found that nutrients and TSS concentrations in the stream showed temporal variability, and higher concentrations occurred in months with high precipitation and intensive agricultural activities. And, retention of total nitrogen(TN), nitrate(NO- 3-N), ammonium(NH+ 4-N) and total suspended solids(TSS) predominantly occurred in the pond reach and estuary reaches with larger width and low current velocity. Pollutants retained in these reaches accounted for more than 50% of those retained in whole stream. The retention mostly happened in the rain-runoff events and it was 7 to 27 times than that in base flow. The results showed that the channelized reach was the most important source for pollutants release under either runoff or base flow, and its release accounted for more than 90% of whole stream release. There was a high spatial variability of nutrients retention in different channelized reaches. The channelized reach directly discharging into the pond did always retain nutrients and TSS under base flow and runoff conditions, whereas the other channelized reaches performed differently in different hydrological conditions. The high spatial and temporal variability of nutrients and TSS in the stream indicated that anthropogenic disturbance of the agricultural headwater stream, such as channelization and excavation, would be expected to decrease the capacity of nutrients retention in the stream. 展开更多
关键词 RETENTION release NUTRIENTS variability stream forms
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An Efficient Outlier Detection Approach on Weighted Data Stream Based on Minimal Rare Pattern Mining 被引量:2
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作者 Saihua Cai Ruizhi Sun +2 位作者 Shangbo Hao Sicong Li Gang Yuan 《China Communications》 SCIE CSCD 2019年第10期83-99,共17页
The distance-based outlier detection method detects the implied outliers by calculating the distance of the points in the dataset, but the computational complexity is particularly high when processing multidimensional... The distance-based outlier detection method detects the implied outliers by calculating the distance of the points in the dataset, but the computational complexity is particularly high when processing multidimensional datasets. In addition, the traditional outlier detection method does not consider the frequency of subsets occurrence, thus, the detected outliers do not fit the definition of outliers (i.e., rarely appearing). The pattern mining-based outlier detection approaches have solved this problem, but the importance of each pattern is not taken into account in outlier detection process, so the detected outliers cannot truly reflect some actual situation. Aimed at these problems, a two-phase minimal weighted rare pattern mining-based outlier detection approach, called MWRPM-Outlier, is proposed to effectively detect outliers on the weight data stream. In particular, a method called MWRPM is proposed in the pattern mining phase to fast mine the minimal weighted rare patterns, and then two deviation factors are defined in outlier detection phase to measure the abnormal degree of each transaction on the weight data stream. Experimental results show that the proposed MWRPM-Outlier approach has excellent performance in outlier detection and MWRPM approach outperforms in weighted rare pattern mining. 展开更多
关键词 outLIER detection WEIGHTED data stream MINIMAL WEIGHTED RARE pattern MINING deviation factors
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Geochemical Stream Sediment Survey in the Wadi Umm Rilan Area,South Eastern Desert,Egypt:A New Occurrence for Gold Mineralization 被引量:2
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作者 Mohamed Abdallah Gad DARWISH 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期1041-1062,共22页
The present paper investigates the stream sediment geochemistry, behavior of gold and associated elements, delineates Au-anomalous sites and defines related sources in the Wadi Umm Rilan area. Fifty three major and tr... The present paper investigates the stream sediment geochemistry, behavior of gold and associated elements, delineates Au-anomalous sites and defines related sources in the Wadi Umm Rilan area. Fifty three major and trace elements were analyzed using ICP-MS and treated applying various statistical and mapping techniques. The results showed a significant difference of mean and median Au and most chemical elements in the three portions of the area, and higher values were recorded in the western portion. Furthermore, Au-anomalous sites appeared in upper and lower parts of the Wadi Umm Rilan, along the tributaries of metavolcanic unit and near granitoid contacts. This indicates the main source of Au mineralization is related to emplacement of granitoid plutons and accompanying hydrothermal solutions. There are significant indications for the presence of more than one mineralization event forming a probable single major episode of mineralization in the area, involving Au, Pb and U mineralizations. Geology, geomorphologic aspects and weathering processes could control stream sediment geochemistry, anomalies of Au and associated elements, elemental association and their dispersion patterns. Therefore, the area is fruitful and regarded as a promising target for Au exploration, using Ag, As, Sb, Cd, Cs, and TI as pathfinder elements. 展开更多
关键词 geochemical survey stream sediments Au mineralization Wadi Umm Rilan area southEastern Desert EGYPT
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Workout Action Recognition in Video Streams Using an Attention Driven Residual DC-GRU Network 被引量:2
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作者 Arnab Dey Samit Biswas Dac-Nhuong Le 《Computers, Materials & Continua》 SCIE EI 2024年第5期3067-3087,共21页
Regular exercise is a crucial aspect of daily life, as it enables individuals to stay physically active, lowers thelikelihood of developing illnesses, and enhances life expectancy. The recognition of workout actions i... Regular exercise is a crucial aspect of daily life, as it enables individuals to stay physically active, lowers thelikelihood of developing illnesses, and enhances life expectancy. The recognition of workout actions in videostreams holds significant importance in computer vision research, as it aims to enhance exercise adherence, enableinstant recognition, advance fitness tracking technologies, and optimize fitness routines. However, existing actiondatasets often lack diversity and specificity for workout actions, hindering the development of accurate recognitionmodels. To address this gap, the Workout Action Video dataset (WAVd) has been introduced as a significantcontribution. WAVd comprises a diverse collection of labeled workout action videos, meticulously curated toencompass various exercises performed by numerous individuals in different settings. This research proposes aninnovative framework based on the Attention driven Residual Deep Convolutional-Gated Recurrent Unit (ResDCGRU)network for workout action recognition in video streams. Unlike image-based action recognition, videoscontain spatio-temporal information, making the task more complex and challenging. While substantial progresshas been made in this area, challenges persist in detecting subtle and complex actions, handling occlusions,and managing the computational demands of deep learning approaches. The proposed ResDC-GRU Attentionmodel demonstrated exceptional classification performance with 95.81% accuracy in classifying workout actionvideos and also outperformed various state-of-the-art models. The method also yielded 81.6%, 97.2%, 95.6%, and93.2% accuracy on established benchmark datasets, namely HMDB51, Youtube Actions, UCF50, and UCF101,respectively, showcasing its superiority and robustness in action recognition. The findings suggest practicalimplications in real-world scenarios where precise video action recognition is paramount, addressing the persistingchallenges in the field. TheWAVd dataset serves as a catalyst for the development ofmore robust and effective fitnesstracking systems and ultimately promotes healthier lifestyles through improved exercise monitoring and analysis. 展开更多
关键词 Workout action recognition video stream action recognition residual network GRU ATTENTION
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Attenuation of arsenic in a karst subterranean stream and correlation with geochemical factors: A case study at Lihu,South China 被引量:6
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作者 Liankai Zhang Hui Yang +2 位作者 Jiansheng Tang Xiaoqun Qin Au Yik Yu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第11期2222-2230,共9页
Arsenic (As) pollutants generated by human activities in karst areas flow into subterranean streams and contaminate groundwater easily because of the unique hydrogeological characteristics of karst areas. To elucida... Arsenic (As) pollutants generated by human activities in karst areas flow into subterranean streams and contaminate groundwater easily because of the unique hydrogeological characteristics of karst areas. To elucidate the reaction mechanisms of arsenic in karst subterranean streams, physical-chemical analysis was conducted by an inductively coupled plasma mass spectrometer and an X-ray fluorescence spectrometer. The results show that inorganic species account for most of the total arsenic, whereas organic arsenic is not detected or occurs in infinitesimal amounts. As(III) accounts for 51.0% ± 9.9% of the total inorganic arsenic. Arsenic attenuation occurs and the attenuation rates of total As, As(III) and As(V) in the Lihu subterranean stream are 51%, 36% and 59%, respectively. To fully explain the main geochemical factors influencing arsenic attenuation, SPSS 13.0 and CANOCO 4.5 bundled with CanoDraw for Windows were used for simple statistical analysis and redundancy analysis (RDA). Eight main factors, i.e., sediment iron (SFe), sediment aluminum (SAI), sediment calcium (SCa), sediment organic matter (SOM), sediment manganese (SMn), water calcium (WCa^2+), water magnesium (WMg^2+), and water bicarbonate ion (WILCOX) were extracted from thirteen indicators. Their impacts on arsenic content rank as: SFe〉SCa〉WCa^2+〉SAl〉wHCO3^-〉SMn〉SOM〉WMg^2+. Of these factors, SFe, SAl, SCa, SOM, SMn, WMg^2+ and WCa&2+ promote arsenic attenuation, whereas WHCO3^- inhibits it. Further investigation revealed that the redox potential (Eh) and pH are adverse to arsenic removal. The dramatic distinction between karst and non-karst terrain is that calcium and bicarbonate are the primary factors influencing arsenic migration in karst areas due to the high calcium concentration and alkalinity of karst water. 展开更多
关键词 Karst subterranean stream Sediment Arsenic Geochemical factors Redundancy analysis
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CA-AODV: Congestion Adaptive AODV Routing Protocol for Streaming Video in Mobile Ad Hoc Networks 被引量:3
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作者 B. RAMESH D. MANJULA 《International Journal of Communications, Network and System Sciences》 2008年第4期322-328,共7页
Whenever streaming of multimedia based data such as video, audio and text is performed traffic will be more and network becomes congested in mobile ad hoc networks. The present routing protocols are not able to cope u... Whenever streaming of multimedia based data such as video, audio and text is performed traffic will be more and network becomes congested in mobile ad hoc networks. The present routing protocols are not able to cope up with this situation. It is observed that network congestion is the dominant reason for packet loss, longer delay and delay jitter in streaming video. Most of the present routing protocols are not designed to adapt to congestion control. We propose a new routing protocol, Congestion Adaptive AODV Routing Protocol (CA-AODV), to address the congestion issues considering delay, packet loss and routing overhead. To evaluate their performance, we have considered mpeg4 for streaming video data using network simulator (NS2). CA-AODV outperforms present protocols in delivery ratio and delay, while introducing less routing protocol overhead. The result demonstrates that integrating congestion adaptive mechanisms with AODV is a promising way to improve performance for heavy traffic load in multimedia based mobile ad hoc networks. 展开更多
关键词 AODV streamING CONGESTION MULTIMEDIA VIDEO
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Runtime reconfiguration of data services for dealing with out-of-range stream fluctuation in cloud-edge environments 被引量:1
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作者 Shouli Zhang Chen Liu +1 位作者 Xiaohong Li Yanbo Han 《Digital Communications and Networks》 SCIE CSCD 2022年第6期1014-1026,共13页
The integration of cloud and IoT edge devices is of significance in reducing the latency of IoT stream data processing by moving services closer to the edge-end.In this connection,a key issue is to determine when and ... The integration of cloud and IoT edge devices is of significance in reducing the latency of IoT stream data processing by moving services closer to the edge-end.In this connection,a key issue is to determine when and where services should be deployed.Common service deployment strategies used to be static based on the rules defined at the design time.However,dynamically changing IoT environments bring about unexpected situations such as out-of-range stream fluctuation,where the static service deployment solutions are not efficient.In this paper,we propose a dynamic service deployment mechanism based on the prediction of upcoming stream data.To effectively predict upcoming workloads,we combine the online machine learning methods with an online optimization algorithm for service deployment.A simulation-based evaluation demonstrates that,compared with those state-of-the art approaches,the approach proposed in this paper has a lower latency of stream processing. 展开更多
关键词 IoT stream processing Edge computing out-of-Range stream fluctuation Dynamic service deployment
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Assessment of trace metals contamination in stream sediments and soils in Abuja leather mining, southwestern Nigeria 被引量:1
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作者 Abiola Oyebamiji Adegbola Odebunmi +1 位作者 Hu Ruizhong Atta Rasool 《Acta Geochimica》 EI CAS CSCD 2018年第4期592-613,共22页
This study is aimed at determining the level of environmental degradation as well as the concentration of trace elements in soil and stream sediments in order to evaluate the environmental impact of the mining operati... This study is aimed at determining the level of environmental degradation as well as the concentration of trace elements in soil and stream sediments in order to evaluate the environmental impact of the mining operation.Twenty-five(25) soils and ten(10) stream sediment samples were collected from the study area. The physicochemical parameters were determined using appropriate instrumentation with the aid of a digital p H meter(Milwaukee meter) to measure the p H and electrical conductivity, total dissolved solids, moisture content and loss on ignition of the soil and stream sediment samples. The p H of the soil sample ranged from(6.10 to 7.19); Electrical conductivity ranged from(21.3 to 279.4 μS/cm), moisture content varied from(0.60% to 7.20%), and the LOI ranged from(2.03% to 18.62%). The results of the analysis showed that the concentrations of the trace elements in the soils and stream sediment samples were slightly higher than the background values. Plots of the trace elements in stream sediment samples show moderate, consistent decrease downstream except at points where there was mine water discharge into the main river. The pollution levels of heavy metals were examined in stream sediment and soil samples using different assessable indices, such as the enrichment factor, which showed significant-moderate enrichment for Cr, Th, Nb, Zn, Pb, Y and Zr and the geoaccumulation index, which showed practically moderate contamination with Cr, Ni and Sr based on regional background reference values. Geo-accumulation index and contamination index for soils and stream sediment revealed uncontaminated to moderate contamination. Likewise,elements with moderate contamination were Cr, Ni and Sr.The Pearson correlation showed that there were significant positive associations among selected metals in soil and stream sediment samples. 展开更多
关键词 Trace metals stream sediments Geo-accumulation index - PCA Soil Southwestern Nigeria
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Stream temperature dynamics in Nam Co basin, southern Tibetan Plateau 被引量:1
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作者 GAO Tan-guang KANG Shi-chang +3 位作者 ZHANG Ting-jun YANG Da-qing SHANG Jian-guo QIN Xiang 《Journal of Mountain Science》 SCIE CSCD 2017年第12期2458-2470,共13页
Stream temperatures are sensitive to climate change and runoff regime variations. A comprehensive understanding on the effects of glacial melting on the stream temperatures are important in the Tibetan Plateau, of whi... Stream temperatures are sensitive to climate change and runoff regime variations. A comprehensive understanding on the effects of glacial melting on the stream temperatures are important in the Tibetan Plateau, of which contains the largest ice volume outside Polar Regions. This study documented the high-resolution stream temperature thermal regimes from glacier-fed and non-glacial rivers at four sites, versus a high-resolution glacier mass balance monitoring at Zhadang glacier, during summer melt seasons from 2007-2009 in the Nam Co basin of southern Tibetan Plateau. The results showed mean summer stream temperature and magnitude of daily thermal variation were lower at all sites when compared with alpine glacierized environments at lower latitudes. Mean stream temperatures for glacier-fed rivers(4.0℃ to 6.5℃)were minimum and least variable near the glacier terminus with increasing toward downstream(+0.13℃ km^(–1) to +0.28℃ km^(–1)). Meanwhile, stream temperature in 2008 was similar to that in 2007 and2009. For the non-glacial rivers, mean stream temperatures was about 9.0℃ with significantly warmer in summer months in 2009 and 2007 than that in 2008. These differences indicated that stream temperature was strongly influenced by discharge and precipitation. Particularly, the glacier mass balance played a large role on the stream temperature directly when the glacier melt contributed more than 50% of the glacial river runoff. Our results demonstrated the stream thermal variability from southern Tibetan rivers and provided new insight into the influence of glacier mass balance on stream thermal variability in high-altitude river system. 展开更多
关键词 stream temperature Thermal regime Glacier mass balance Tibetan Plateau
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Factor Analysis of Stream Sediment Geochemical Data from Onyami Drainage System, Southwestern Nigeria 被引量:1
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作者 Ovie Odokuma-Alonge John Adeyinka Adekoya 《International Journal of Geosciences》 2013年第3期656-661,共6页
An R-mode quartimax rotated factor matrix was applied to a statistical study of stream sediment geochemical data from Onyami drainage system within Igarra area in southwestern Nigeria. The area is underlain by the gne... An R-mode quartimax rotated factor matrix was applied to a statistical study of stream sediment geochemical data from Onyami drainage system within Igarra area in southwestern Nigeria. The area is underlain by the gneiss-migmatite complex, the low grade supracrustal schist belts and the Pan-African granitoids which intruded both the gneiss-migmatite complex and the supracrustal units. A four-factor model which accounts for 76.49% of the total variance of the stream sediment geochemical data was established. Factor 1 (Sc-Ga-V-La-Ni-Co-Ag-Bi-Sr-Pb-Hf-Nb-Cu-Cr) probably defines an underlying complex granitic lithology with contributions from mafic and ultramafic rocks. Factor 2 (Th-U) is attributable to a granitic lithology which reflects the parent rock as the influencing factor. Factor 3 (Mo-Nb-Zn) appears to define a minor sulphide mineralization associated with granitic rocks that intruded the schists and granite gneiss in the area. Factor 4 indicates the occurrence of gold and its pathfinder element, As, in the study area. This inference is consistent with the reported occurrence and mining of gold during the colonial era in Dagbala, which lies within the Onyami river catchment area. 展开更多
关键词 stream SEDIMENT Survey GEOCHEMISTRY FACTOR Analysis
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Influence of Flow Regime on the Vegetation Zonation along Mountain Streams in the Western Cape, South Africa 被引量:1
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作者 Erwin Jacobus Joannes SIEBEN 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1484-1498,共15页
Zonation patterns of riparian vegetation have been sampled and described in mountain streams in two catchments in the Hottentots-Holland Mountains, Western Cape, South Africa. Six main vegetation types that differ in ... Zonation patterns of riparian vegetation have been sampled and described in mountain streams in two catchments in the Hottentots-Holland Mountains, Western Cape, South Africa. Six main vegetation types that differ in structure and species composition, are dominant along these river banks: Aquatic vegetation, Wetbanks, Palmiet, Scrub, Forest and Shrubland(Fynbos). The study aims to correlate the vegetation patterns to flooding patterns, in particular the inundation frequency and stream power. A problem arises: because these catchments are ungauged, like most mountain catchments, with the only weirs at the downstream end of the catchment. Discharge data at the weirs are extrapolated to the sites upstream by multiplication with a factor based on the size of the subcatchment that drains through a sample site. In this way, recurrence intervals for floods in mountain streams are derived. Discharges at sites are also calculated using bed roughness(Manning's n) and slope in straight sections with uniform flow conditions. Stream power is derived from the discharges calculated in this manner. The combination of stream power and recurrence intervals explains the occurrence of most vegetation types occurring on the banks, except for one type: Afromontane Forest. This type is probably more dependent on other factors, such as protection from fire and the depth of the groundwater table. 展开更多
关键词 Hydrology Hydraulics Riparian vegetation Mountain streams Floods stream power Manning's n.
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Strategy for Data Stream Processing Based on Measurement Metadata: An Outpatient Monitoring Scenario 被引量:1
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作者 Mario Diván Luis Olsina Silvia Gordillo 《Journal of Software Engineering and Applications》 2011年第12期653-665,共13页
In this work we discuss SDSPbMM, an integrated Strategy for Data Stream Processing based on Measurement Metadata, applied to an outpatient monitoring scenario. The measures associated to the attributes of the patient ... In this work we discuss SDSPbMM, an integrated Strategy for Data Stream Processing based on Measurement Metadata, applied to an outpatient monitoring scenario. The measures associated to the attributes of the patient (entity) under monitoring, come from heterogeneous data sources as data streams, together with metadata associated with the formal definition of a measurement and evaluation project. Such metadata supports the patient analysis and monitoring in a more consistent way, facilitating for instance: i) The early detection of problems typical of data such as missing values, outliers, among others;and ii) The risk anticipation by means of on-line classification models adapted to the patient. We also performed a simulation using a prototype developed for outpatient monitoring, in order to analyze empirically processing times and variable scalability, which shed light on the feasibility of applying the prototype to real situations. In addition, we analyze statistically the results of the simulation, in order to detect the components which incorporate more variability to the system. 展开更多
关键词 MEASUREMENT Data stream Processing C-INCAMI STATISTICAL Analysis
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Heavy Metal Dispersion in Stream Sediments in River Iyiudene, Abakaliki South-Eastern Nigeria: Source, Distribution Pattern, and Contamination Assessment 被引量:1
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作者 Emmanuel U. Nwazue Erepamo J. Omietimi +3 位作者 Eniye Mienye Osayamen J. Imarhiagbe Olumide A. Adeosun Paulinus N. Nnabo 《Journal of Geoscience and Environment Protection》 2022年第7期48-69,共22页
River Iyiudene is a vital distributary resource in Abakaliki, southeastern Nigeria and conveys an abundant amount of sediments to provincial and residual ecosystems. Although the importance of the river cannot be over... River Iyiudene is a vital distributary resource in Abakaliki, southeastern Nigeria and conveys an abundant amount of sediments to provincial and residual ecosystems. Although the importance of the river cannot be overemphasized, the geochemistry of its stream sediments is less investigated. Twenty (20) stream sediment samples were taken at the centre of the river channels to represent the entire drainage area well and avoid collapsed bank materials. The stream sediment samples were used to determine the dispersion, contamination status and sources of heavy metal concentrations. Total elemental digestion accompanied this with the use of aqua regia, an admixture of Hydrochloric acid (HCl) and Nitric acid (HNO<sub>3</sub>) in the ratio of 3:1 using the atomic absorption spectrometer (AAS). The heavy metal concentration levels in River Iyiudene were low compared with sediments from Imo River, Gulf of California, Upper continental crust, Average shale and surface horizons, excluding Cd, which showed high concentration levels than the other reference studies. The results delineated a wide contrast in the concentration levels of the heavy metals, with the mean contents in the order Zn > Cu > Pb > Cd > Ni > As. The pollution evaluation utilizing the Effect range low (ERL), Effect range median (ERM), single pollution index, and geo-accumulation index revealed Cd contamination. This study indicates that the heavy metals were sourced from the natural geological background of the river basin and possibly from agricultural runoff and atmospheric pollutants. 展开更多
关键词 Benue Trough Heavy Metals CONTAMINATION stream Sediments Single Pollution Index Correlation Matrix
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Joint routing and rate allocation for multiple video streams in ad-hoc wireless networks
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作者 SINGH Jatinder Pal GIROD Bernd 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期727-736,共10页
The support for multiple video streams in an ad-hoc wireless network requires appropriate routing and rate allocation measures ascertaining the set of links for transmitting each stream and the encoding rate of the vi... The support for multiple video streams in an ad-hoc wireless network requires appropriate routing and rate allocation measures ascertaining the set of links for transmitting each stream and the encoding rate of the video to be delivered over the chosen links. The routing and rate allocation procedures impact the sustained quality of each video stream measured as the mean squared error (MSE) distortion at the receiver, and the overall network congestion in terms of queuing delay per link. We study the trade-off between these two competing objectives in a convex optimization formulation, and discuss both centralized and dis- tributed solutions for joint routing and rate allocation for multiple streams. For each stream, the optimal allocated rate strikes a balance between the selfish motive of minimizing video distortion and the global good of minimizing network congestions, while the routes are chosen over the least-congested links in the network. In addition to detailed analysis, network simulation results using ns-2 are presented for studying the optimal choice of parameters and to confirm the effectiveness of the proposed measures. 展开更多
关键词 AD-HOC wireless networks VIDEO streaming Rate allocation MULTI-PATH RoutING
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BloomRouter:A Framework for Dissemination of Compressed XML Stream
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作者 BAO Xiao-yuan TANG Shi-wei +2 位作者 YANG Dong-qing SONG Zai-sheng WU Ling 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期100-106,共7页
As our best knowledge, in the Publish/Subscribe application environment, few research work has been done on the dissemination and routing of compressed XML (extended markup language) data. A high-speed compressed XM... As our best knowledge, in the Publish/Subscribe application environment, few research work has been done on the dissemination and routing of compressed XML (extended markup language) data. A high-speed compressed XML data routing and dissemination framework BloomRouter is proposed. In BloomRouter, a Bloom Filter based prefilte ring mechanism is used to filter out compressed XML elements that users do not care; after that an interval tree dis seminator forwards target elements to the corresponding end users by matching the incomming compressed XML elements with indexed users' query regions. Based on this framework, we can efficiently filter/query the compressed incoming XML data, and then route the query result to the corresponding subseriber. 展开更多
关键词 XML bloom filters compression data stream
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Dissolved organic sulfur in streams draining forested catchments in southern China
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作者 Zhanyi Wang Xiaoshan Zhang +3 位作者 Zhangwei Wang Yi Zhang Bingwen Li Rolf Vogt 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第4期704-710,共7页
Dissolved organic sulfur (DOS) is an important fraction for sulfur mobilization in ecosystem. In this work stream waters were sampled in 25 forested sites in southern China to study the dissolved sulfur fractions. D... Dissolved organic sulfur (DOS) is an important fraction for sulfur mobilization in ecosystem. In this work stream waters were sampled in 25 forested sites in southern China to study the dissolved sulfur fractions. Dissolved sulfur was fractionated into dissolved organic sulfur (DOS) and inorganic sulfate (SO]-) for 95 stream water samples. The results showed that the concentration of DOS ranged from 0 to 13.1 mg/L (average 1,3 mg/L) in all the streams, High concentrations of DOS in stream waters were found in the sites with high concentrations of sulfate. DOS constituted less than 60.1% of dissolved sulfur (average 17.9%). Statistical analysis showed that DOS concentration was correlated with SO42- in streams waters and total sulfur in surface layer soils. The results also showed that DOS concentration in stream waters had a seasonal variation, but no trends were found with it. The implication was that the long term sulfur deposition had led the increase of the concentration and fraction of DOS in stream waters in acid rain prevailing regions 展开更多
关键词 dissolved organic sulfur stream water Chinese forests sulfur deposition
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Mineralogy and geochemistry of fine-grained Dahab stream sediments, Southeastern Sinai, Egypt: emphasis on the intergrowths of Fe–Ti oxides
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作者 Adel A.Surour Ahmed.M.A.El-Kammar +1 位作者 Ebtisam H.Arafa Hala M.Korany 《Acta Geochimica》 EI CAS CSCD 2021年第6期871-894,共24页
Mineralogical and geochemical characteristics of stream sediments collected from 30 stations in the Dahab-Wadi Kid area(southeastern Sinai,Egypt)are presented.The studied sediments contain considerable amounts of heav... Mineralogical and geochemical characteristics of stream sediments collected from 30 stations in the Dahab-Wadi Kid area(southeastern Sinai,Egypt)are presented.The studied sediments contain considerable amounts of heavy minerals,including abundant Fe–Ti oxides,with up to 25.94%index figure that measures the relative abundance of heavy minerals to light minerals.Immaturity of the sediments and nature of Fe–Ti oxide intergrowths,in addition to some non-opaque heavy minerals,indicate multiple provenances with contributions from a variety of Neoproterozoic mafic to felsic intrusions.Appreciable amounts of heavy minerals are derived from schists that belong to the so-called Wadi Kid volcanosedimentary group.Owing to the considerable contribution of the felsic intrusions represented by within-plate granites,the sediments are enriched in REE-bearing minerals(e.g.,monazite,cerianite,La-cerianite and allanite),V-bearing thorite,zircon,and a ZrO_(2) phase.The majority of Fe–Ti oxides are derived from the mafic intrusions,and they show evidence of pre-,syn-and post-depositional phases of alteration and formation of intergrowths.As to the geochemical signature of the bulk silt fraction,there is remarkable enrichment of LREEs with distinct negative Eu anomaly,and this supports dominance of a provenance dominated by felsic intrusions(i.e.,the A-type within-plate granite and associated pegmatites).Also,the felsic provenance is responsible for slight abnormality of ∑PU+Th content(up to~37 ppm)and few anomalous samples bear uraniferous zircon and Ce-type monazite.The present paper sheds light on the fertility of the Dahab stream sediments in some economic minerals for possible future exploitation,not for gold only,but for potential REEbearing minerals that are needed for a wide spectrum of modern technological industries. 展开更多
关键词 Dahab stream sediments Silt fraction Fe-Ti oxides Textural variations Rees enrichment
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