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Application of QUAL2K for Water Quality Modeling of River Ghataprabha (India) 被引量:1
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作者 P.B. Kalburgi C.B. Shivayogimath B.K. Purandara 《Journal of Environmental Science and Engineering》 2010年第12期6-11,共6页
River Ghataprabha, during its course through Belgaum district in Karnataka state (India), receives untreated domestic waste from Gokak town and other neighboring villages situated on the bank of the river. The prese... River Ghataprabha, during its course through Belgaum district in Karnataka state (India), receives untreated domestic waste from Gokak town and other neighboring villages situated on the bank of the river. The present study involves the application of water quality model QUAL2K to predict the water quality of this polluted segment of the river. The model was calibrated and validated for biochemical oxygen demand (BOD), dissolved oxygen (DO) and total nitrogen (TN) in pre-monsoon season. Data for calibration and validation were obtained after the field and laboratory measurements. The performance of the model was evaluated using statistics based on standard errors (SE) and mean multiplicative errors (MME). The model represented the field data quite well with some exceptions. In spite of some differences between the measured and simulated data sets at some points, the calibration and validation results are acceptable especially for the developing countries where the financial resources are often limited for frequent monitoring campaigns and higher accuracy data analysis. 展开更多
关键词 Water quality modeling QUAL2K river pollution river Ghataprabha BOD modeling DO modelling
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Human-Centric Composite-Quality Modeling and Assessment for Virtual Desktop Clouds
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作者 Yingxiao Xu Prasad Calyam +3 位作者 David Welling Saravanan Mohan Alex Berryman Rajiv Ramnath 《ZTE Communications》 2013年第1期27-36,共10页
There are several motivations, such as mobility, cost, and secu- rity, that are behind the trend of traditional desktop users transi- tioning to thin-client-based virtual desktop clouds (VDCs). Such a trend has led ... There are several motivations, such as mobility, cost, and secu- rity, that are behind the trend of traditional desktop users transi- tioning to thin-client-based virtual desktop clouds (VDCs). Such a trend has led to the rising importance of human-centric performance modeling and assessment within user communities that are increasingly making use of desktop virtualization. In this paper, we present a novel reference architecture and its eas- ily deployable implementation for modeling and assessing objec- tive user quality of experience (QoE) in VDCs. This architec- ture eliminates the need for expensive, time-consuming subjec- tive testing and incorporates finite-state machine representa- tions for user workload generation. It also incorporates slow-mo- tion benchmarking with deep-packet inspection of application task performance affected by QoS variations. In this way, a "composite-quality" metric model of user QoE can be derived. We show how this metric can be customized to a particular user group profile with different application sets and can be used to a) identify dominant performance indicators and troubleshoot bottlenecks and b) obtain both absolute and relative objective user QoE measurements needed for pertinent selection of thin-client encoding configurations in VDCs. We validate our composite-quality modeling and assessment methodology by us- ing subjective and objective user QoE measurements in a re- al-world VDC called VDPilot, which uses RDP and PCoIP thin-client protocols. In our case study, actual users are pres- ent in virtual classrooms within a regional federated university system. 展开更多
关键词 virtual desktops quality modeling and assessment performancebenchmarking thin-client protocol adaptation objective QoEmetrics
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Using a Coupled Air Quality Modeling System for the Development of an Air Quality Plan in Madrid (Spain): Source Apportionment and Analysis Evaluation of Mitigation Measures
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作者 Raúl Arasa Anna Domingo-Dalmau Ricardo Vargas 《Journal of Geoscience and Environment Protection》 2016年第3期46-61,共16页
In this contribution, we use a coupled air quality modelling system (AQM) as a tool to design and develop an air quality plan in Madrid. AQM has allowed us to obtain a preliminary evaluation of the effect of mitigatio... In this contribution, we use a coupled air quality modelling system (AQM) as a tool to design and develop an air quality plan in Madrid. AQM has allowed us to obtain a preliminary evaluation of the effect of mitigation measures over regional and local air quality levels. To achieve these goals, we have prepared a sophisticated AQM, coupling the meteorological model WRF, the emission model AEMM, and the photochemical model CMAQ. AQM was evaluated using the whole modelling year 2010 working with high horizontal resolution, 3 km for the region of Madrid and 1km for urban metropolitan area of Madrid. Two different analyses have been realized: a source apportionment exercise following a zero-out methodology to obtain the contribution to the air quality levels of the different emission sector;and an evaluation of the main mitigation measures considered in the air quality plan using sensitivity analysis. The air quality plan was focused on the improvement of NO<sub>2</sub> levels and AQM analyzed the effect of the mitigation measures during ten episodes of 2011 where NO<sub>2</sub> or O<sub>3</sub> levels were the highest of the year;so we analyzed the effect of the mitigation plan in worst conditions. Results provided by the AQM system show that it accomplishes the European Directive modelling uncertainty requirements and the mean absolute gross error for 1-h maximum daily NO<sub>2</sub> is 31% over locations with higher levels of this atmospheric pollutant;the road traffic is the main contributor to the air quality levels providing a 81% for NO<sub>2</sub>, 67% for CO and 46% for PM<sub>10</sub>;measures defined in the plan achieve to reduce up to 11 μgm<sup>-3</sup> NO<sub>2</sub> levels offering highest reductions over urban areas with traffic influence. 展开更多
关键词 Environmental Assessment Air quality Modelling CMAQ EMISSIONS Madrid Air quality Plan Mitigation Measures
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Evaluation of the Impact of Refined Quality Control Management Model on the Qualified Rate of Disinfection and Sterilization of Surgical Instruments in the Sterilization Supply Center 被引量:1
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作者 Qin Liu 《Journal of Clinical and Nursing Research》 2024年第1期168-173,共6页
Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization sup... Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization supply center from January 2021 to January 2023.The work situation before January 31,2022,was classified as the control group;a routine quality control management model was implemented,and the work situation after January 31,2022,was classified as the observation group.The quality of medical device management and department satisfaction between the two groups were compared.Results:The timely recovery and supply rate,classification and cleaning pass rate,disinfection pass rate,packaging pass rate,sterilization pass rate,and department satisfaction score in the observation group were all higher than those of the control group(P<0.05).Conclusion:Implementing a refined quality control management model in the sterilization supply center can improve the quality management level of medical devices and department satisfaction and is worthy of promotion. 展开更多
关键词 Refined quality control management model Sterilization supply center Disinfection and sterilization pass rate
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Effect analysis of applying high-quality service model to surgical nursing
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作者 Li Chen Qiu-Mei Tu +4 位作者 Zhao-Di Guo Xiao-Wei Zhu Wei Wang Hui-Fang Xie Yuan Ye 《World Journal of Clinical Cases》 SCIE 2024年第19期3744-3751,共8页
BACKGROUND Surgical care of the hand plays a crucial role in the medical field,as problems with the hand can profoundly affect a patient's quality of life and function.In order to meet the needs of patients,improv... BACKGROUND Surgical care of the hand plays a crucial role in the medical field,as problems with the hand can profoundly affect a patient's quality of life and function.In order to meet the needs of patients,improve patient satisfaction and improve treatment outcomes,high-quality service models have been introduced in the field of nursing.AIM To explore the effect analysis of applying high-quality service model to surgical nursing.METHODS We conducted a retrospective study of patients who underwent hand surgery at our hospital between 2019 and 2022,using a quality service model that included improved patient education,pain management,care team collaboration,and effective communication.Another group of patients received traditional care as a control group.We compared postoperative recovery,satisfaction,complication rate,and length of hospital stay between the two groups.Inferential statistics were used to compare the difference between the two groups by independent sample t test,Chi-square test and other methods to evaluate the effect of intervention measures.RESULTS Postoperative recovery time decreased from 17.8±2.3 d to 14.5±2.1 d,pain score decreased from 4.7±1.9 to 3.2±1.4,and hand function score increased from 78.4±7.1 to 88.5±6.2.In terms of patient satisfaction,the quality service model group scored 87.3±5.6 points,which was significantly higher than that of the traditional care group(74.6±6.3 points).At the same time,patients'understanding of medical information also improved from 6.9±1.4 to 8.6±1.2.In terms of postoperative complications,the application of the quality service model reduced the incidence of postoperative complications from 26%to 10%,the incidence of infection from 12%to 5%,and the incidence of bleeding from 10%to 3%.The reduction in these data indicates that the quality service model plays a positive role in reducing the risk of complications.In addition,the average hospital stay of patients in the quality service model group was shortened from 6.8±1.5 d to 5.2±1.3 d,and the hospitalization cost was also reduced from 2800±600 yuan to 2500±500 yuan.CONCLUSION Applying a quality service model to hand surgery care can significantly improve patient clinical outcomes,including faster recovery,less pain,greater satisfaction,and reduced complication rates. 展开更多
关键词 Hand surgery nursing quality service model Clinical outcomes Patient satisfaction COLLABORATION Pain management
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Effects of three-dimensional quality assessment nursing intervention on efficacy and disease management of patients undergoing esophageal cancer surgery
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作者 Hai-Yan Wu Jie Jin +3 位作者 Chen Chen Jing-Jing Xu Qi Jiang Dong-Mei Lu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期2979-2985,共7页
BACKGROUND Esophageal cancer is one of the most common malignant tumors.The three-dimensional quality structure model is a quality assessment theory that includes three dimensions:Structure,process,and results.AIM To ... BACKGROUND Esophageal cancer is one of the most common malignant tumors.The three-dimensional quality structure model is a quality assessment theory that includes three dimensions:Structure,process,and results.AIM To investigate the effects of nursing interventions with three-dimensional quality assessment on the efficacy and disease management ability of patients undergoing esophageal cancer surgery.METHODS In this prospective study,the control group received routine nursing,and the intervention group additionally received a three-dimensional quality assessment intervention based on the above routine care.Self-efficacy and patient disease management abilities were evaluated using the General Self-Efficacy Scale(GSES)and Exercise of Self-Care Agency scale,respectively.IBM SPSS Statistics for Windows,version 17.0,was used for the data processing.RESULTS This study recruited 112 patients who were assigned to the control and experi-mental groups(n=56 per group).Before the intervention,there was no significant difference in GSES scores between the two groups(P>0.05).After the inter-vention,the GSES scores of both groups increased,with the experimental group showing higher values(P<0.05).At the time of discharge and three months after discharge,the scores for positive attitudes,self-stress reduction,and total score of health promotion in the experimental group were higher than those in the control group(P<0.05).CONCLUSION The implementation of a three-dimensional quality structure model for postoperative patients with esophageal cancer can effectively improve their self-management ability and self-efficacy of postoperative patients. 展开更多
关键词 Esophageal cancer Three-dimensional quality structure model SELF-EFFICACY Disease management ability
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Mapping anthropogenic emissions in China at 1 km spatial resolution and its application in air quality modeling 被引量:14
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作者 Bo Zheng Jing Cheng +7 位作者 Guannan Geng Xin Wang Meng Li Qinren Shi Ji Qi Yu Lei Qiang Zhang Kebin He 《Science Bulletin》 SCIE EI CSCD 2021年第6期612-620,M0004,共10页
New challenges are emerging in fine-scale air quality modeling in China due to a lack of high-resolution emission maps.Currently,only a few emission sources have accurate geographic locations(point sources),while a la... New challenges are emerging in fine-scale air quality modeling in China due to a lack of high-resolution emission maps.Currently,only a few emission sources have accurate geographic locations(point sources),while a large part of sources,including industrial plants,are estimated as provincial totals(area sources)and spatially disaggregated onto grid cells based on proxies;this approach is reasonable to some extent but is highly questionable at fine spatial resolutions.Here,we compile a new comprehensive point source database that includes nearly 100,000 industrial facilities in China.We couple it with the frame of Multi-resolution Emission Inventory for China(MEIC),estimate point source emissions,combine point and area sources,and finally map China’s anthropogenic emissions of 2013 at the spatial resolution of 30’’*30’’(~1 km).Consequently,the percentages of point source emissions in the total emissions increase from less than 30%in the MEIC up to a maximum of 84%for SO_(2)in 2013.The new point source-based emission maps show the uncoupled distribution of emissions and populations in space at fine spatial scales,however,such a pattern cannot be reproduced by any spatial proxy used in the conventional emissions mapping.This new accurate high-resolution emission mapping approach reduces the modeled biases of air pollutant concentrations in the densely populated areas compared to the raw MEIC inventory,thus improving the assessment of population exposure. 展开更多
关键词 Anthropogenic emission inventory High-resolution mapping Air quality modeling
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Artificial neural network modeling of water quality of the Yangtze River system:a case study in reaches crossing the city of Chongqing 被引量:11
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作者 郭劲松 李哲 《Journal of Chongqing University》 CAS 2009年第1期1-9,共9页
An effective approach for describing complicated water quality processes is very important for river water quality management. We built two artificial neural network(ANN) models,a feed-forward back-propagation(BP) mod... An effective approach for describing complicated water quality processes is very important for river water quality management. We built two artificial neural network(ANN) models,a feed-forward back-propagation(BP) model and a radial basis function(RBF) model,to simulate the water quality of the Yangtze and Jialing Rivers in reaches crossing the city of Chongqing,P. R. China. Our models used the historical monitoring data of biological oxygen demand,dissolved oxygen,ammonia,oil and volatile phenolic compounds. Comparison with the one-dimensional traditional water quality model suggest that both BP and RBF models are superior; their higher accuracy and better goodness-of-fit indicate that the ANN calculation of water quality agrees better with measurement. It is demonstrated that ANN modeling can be a tool for estimating the water quality of the Yangtze River. Of the two ANN models,the RBF model calculates with a smaller mean error,but a larger root mean square error. More effort to identify out the causes of these differences would help optimize the structures of neural network water-quality models. 展开更多
关键词 water quality modeling Yangtze River artificial neural network back-propagation model radial basis functionmodel
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Software Coupling and Cohesion Model for Measuring the Quality of Software Components
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作者 Zakarya Abdullah Alzamil 《Computers, Materials & Continua》 SCIE EI 2023年第12期3139-3161,共23页
Measuring software quality requires software engineers to understand the system’s quality attributes and their measurements.The quality attribute is a qualitative property;however,the quantitative feature is needed f... Measuring software quality requires software engineers to understand the system’s quality attributes and their measurements.The quality attribute is a qualitative property;however,the quantitative feature is needed for software measurement,which is not considered during the development of most software systems.Many research studies have investigated different approaches for measuring software quality,but with no practical approaches to quantify and measure quality attributes.This paper proposes a software quality measurement model,based on a software interconnection model,to measure the quality of software components and the overall quality of the software system.Unlike most of the existing approaches,the proposed approach can be applied at the early stages of software development,to different architectural design models,and at different levels of system decomposition.This article introduces a software measurement model that uses a heuristic normalization of the software’s internal quality attributes,i.e.,coupling and cohesion,for software quality measurement.In this model,the quality of a software component is measured based on its internal strength and the coupling it exhibits with other component(s).The proposed model has been experimented with nine software engineering teams that have agreed to participate in the experiment during the development of their different software systems.The experiments have shown that coupling reduces the internal strength of the coupled components by the amount of coupling they exhibit,which degrades their quality and the overall quality of the software system.The introduced model can help in understanding the quality of software design.In addition,it identifies the locations in software design that exhibit unnecessary couplings that degrade the quality of the software systems,which can be eliminated. 展开更多
关键词 Software coupling measurement software cohesion measurement quality attributes measurement software quality measurement software quality modeling
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High-resolution modeling and evaluation of ozone air quality of Osaka using MM5-CMAQ system 被引量:7
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作者 SHRESTHA Kundan Lal KONDO Akira +1 位作者 KAGA Akikazu INOUE Yoshio 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第6期782-789,共8页
High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with com... High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with complex terrain and land-use. This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka, Japan. The 1-km and 3-kin grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region. High-resolution Grid Point Value-Mesoscale Model (GPV-MSM) data were used after suitable validation. The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone. Daily maxima of ozone were found better simulated by the 1-krn grid domain than the coarser 9-km and 3-km domains, with the maximum improvement in the mean absolute gross error about 3 ppbv. In addition, 1-km grid results fared better than other grids at most of the observation stations that showed noticeable differences in gross error as well as correlation. These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region, such as the Osaka region, which has complex terrain and land-use. 展开更多
关键词 air quality model evaluation OZONE Community Multiscale Air quality MM5 statistical analysis
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Modeling of air quality with a modified two-dimensional Eulerian model: A case study in the Pearl River Delta (PRD) region of China 被引量:4
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作者 CHENG Yan-li BAI Yu-hua LI Jin-long LIU Zhao-rong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第5期572-577,共6页
A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta (PRD) region, China. The most ... A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta (PRD) region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols (SOA) concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3^-, NH4^+, SO4^2-, and SOA were calculated in the fine particle size range (〈2.5 μm). The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign (IMC). Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly O3 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio. 展开更多
关键词 air quality model numerical simulation secondary organic aerosol inorganic aerosol
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Research on Welding Quality Traceability Model of Offshore Platform Block Construction Process
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作者 Jinghua Li Wenhao Yin +1 位作者 Boxin Yang Qinghua Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期699-730,共32页
Quality traceability plays an essential role in assembling and welding offshore platform blocks.The improvement of the welding quality traceability system is conducive to improving the durability of the offshore platf... Quality traceability plays an essential role in assembling and welding offshore platform blocks.The improvement of the welding quality traceability system is conducive to improving the durability of the offshore platform and the process level of the offshore industry.Currently,qualitymanagement remains in the era of primary information,and there is a lack of effective tracking and recording of welding quality data.When welding defects are encountered,it is difficult to rapidly and accurately determine the root cause of the problem from various complexities and scattered quality data.In this paper,a composite welding quality traceability model for offshore platform block construction process is proposed,it contains the quality early-warning method based on long short-term memory and quality data backtracking query optimization algorithm.By fulfilling the training of the early-warning model and the implementation of the query optimization algorithm,the quality traceability model has the ability to assist enterprises in realizing the rapid identification and positioning of quality problems.Furthermore,the model and the quality traceability algorithm are checked by cases in actual working conditions.Verification analyses suggest that the proposed early-warningmodel for welding quality and the algorithmfor optimizing backtracking requests are effective and can be applied to the actual construction process. 展开更多
关键词 quality traceability model block construction process welding quality management long short-term memory quality data backtracking query optimization algorithm
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Water quality changing trends of the Miyun Reservoir 被引量:6
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作者 王建平 程声通 贾海峰 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期215-219,共5页
In order to simulate changes in the water quality of the Miyun Reservoir dueto continuous descent of surface water level, a 3-D ecological hydrodynamic model was developedthrough coupling the water quality analysis si... In order to simulate changes in the water quality of the Miyun Reservoir dueto continuous descent of surface water level, a 3-D ecological hydrodynamic model was developedthrough coupling the water quality analysis simulation program (WASP) with the environmental fluiddynamics code (EFDC). The model was then calibrated and verified. Four scenarios (S1, S21, S22 andS23) were simulated using the model. Results show that the water quality of the Miyun Reservoirunder conditions of low surface water level is apparently affected by different amounts of inflowand different total phosphorus (TP) loadings. The chlorophyll-a concentration might exceed 10 μg/Lin many areas of the Miyun Reservoir (This limitative value is seen as a critical value ofeutrophication) when large loadings of TP enter due to the amount of inflow increasing. Results ofscenario S23 indicate that control of TP loadings can decrease chlorophyll-a concentrationeffectively, and the water quality of the Miyun Reservoir will improve or retain its status quo. 展开更多
关键词 water quality model hydrodynamic model scenario analysis changing trends
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Photochemical Process Modeling and Analysis of Ozone Generation 被引量:5
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作者 王冰 邱彤 陈丙珍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第6期721-729,共9页
Air pollution in modern city and industrial zones has become a serious public concern in recent years in China. Significance of air quality assessment and emission control strategy design is increasing. Most studies i... Air pollution in modern city and industrial zones has become a serious public concern in recent years in China. Significance of air quality assessment and emission control strategy design is increasing. Most studies in China focus on particulate matter(PM), especially PM2.5, while few account for photochemical secondary air pollutions represented by ozone(O3). In this paper, a procedure for air quality simulation with comprehensive air quality model with extensions(CAMx) is demonstrated for studying the photochemical process and ozone generation in the troposphere. As a case study, the CAMx photochemical grid model is used to model ozone over southern part of Beijing city in winter, 2011. The input parameters to CAMx include emission sources, meteorology field data, terrain definition, photolysis status, initial and boundary conditions. The simulation results are verified by theoretical analysis of the ozone generation tendency. The simulated variation tendency of domain-wide average value of hourly ozone concentration coincides reasonably well with the theoretical analysis on the atmospheric photochemical process, demonstrating the effectiveness of the procedure. An integrated model system that cooperates with CAMx will be established in our future work. 展开更多
关键词 comprehensive air quality model with extensions MULTI-SCALE OZONE air quality modeling PHOTOCHEMICAL
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Application of a water quality model for determining instream aeration station location and operational rules:A case study 被引量:3
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作者 Charles S.Melching 《Water Science and Engineering》 EI CAS CSCD 2018年第1期8-16,共9页
Instream aeration has been used as a supplement to secondary treatment or a substitute for tertiary treatment for meeting dissolved oxygen (DO) standards in rivers. Many studies have used water quality models to det... Instream aeration has been used as a supplement to secondary treatment or a substitute for tertiary treatment for meeting dissolved oxygen (DO) standards in rivers. Many studies have used water quality models to determine the number, location, and capacity of instream aeration stations (IASs) needed to meet DO standards in combination with other pollution control measures. DO concentrations have been improved in the North Shore Channel and North Branch Chicago River by the Devon Avenue IAS for more than 35 years. A study was initiated to determine whether it was better to rehabilitate or relocate this station and to determine appropriate operational guidance for the IAS at the selected location. A water quality model capable of simulating DO concentrations during unsteady flow was used to evaluate the proper location for an IAS and operational guidance for this IAS. Three test years, a dry year, a wet year, and an extreme year, were considered in the evaluation. The study found that the Devon Avenue IAS should be rehabilitated as this location performed as well as or better than any of 10 alternative locations. According to the new operational guidance for this IAS, the amount of time with blowers operating could be substantially reduced compared to traditional operations while at the same time the attainment of the DO standards could be increased. This study shows that a carefully designed modeling study is key to effective selection, location, and operation of IASs such that attainment of DO standards can be maximized while operation hours of blowers can be minimized. 展开更多
关键词 Instream aeration Dissolved oxygen Water quality modeling Water quality management Computer simulation
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The Influence and Implications of Climate Change on Water Quality in a Large Water Reservoir in the Southwest, USA
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作者 Deena Hannoun Todd Tietjen Keely Brooks 《American Journal of Climate Change》 2022年第3期197-229,共33页
Maintaining water quality in large reservoirs is crucial to ensure continued delivery of high-quality water to consumers for municipal and agricultural needs. Lake Mead, a large reservoir in the desert southwest, USA,... Maintaining water quality in large reservoirs is crucial to ensure continued delivery of high-quality water to consumers for municipal and agricultural needs. Lake Mead, a large reservoir in the desert southwest, USA, is projected to be affected by both loss of volume and rising air temperatures through the end of the 21<sup>st</sup> century. In this study, reductions in lake volume, coupled with downscaled climate projections for rising air temperatures through the end of the 21<sup>st</sup> century, are incorporated into the 3D hydrodynamic and water quality model for Lake Mead. If current management practices continue in the future, simulations indicate water temperatures will increase in all scenarios and could increase by as much 2&#8451;under the most pessimistic scenarios, but nutrient loads would not increase to concerning levels. Releases from the dam to downstream users are projected to be much warmer, and warmer water temperatures and significant dissolved oxygen in the water column are expected to cause challenges for ecosystem and recreation in the future. Surprisingly, during the Winter and Autumn, retention of heat in Lake Mead is more pronounced at higher surface elevations than the lower elevations as expected. The effects of these projections on the lake water quality and consequently, lake management decisions, are discussed. 展开更多
关键词 Climate Change Lake Management Water quality modeling Lake Mead AEM3D
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Assessment of Point and Nonpoint Sources Pollution in Songhua River Basin,Northeast China by Using Revised Water Quality Model 被引量:14
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作者 YANG Yuhong YAN Baixing SHEN Wanbin 《Chinese Geographical Science》 SCIE CSCD 2010年第1期30-36,共7页
Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin.It is difficult to identify the sources and to quantify th... Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin.It is difficult to identify the sources and to quantify the load, especially in modeling nonpoint source.In this study a revised model was established by integrating point and nonpoint sources into one-dimensional Streeter-Phelps(S-P) model on the basis of real-time hydrologic data and surface water quality monitoring data in the Jilin Reach of the Songhua River Basin.Chemical oxygen demand(COD) and ammonia nitrogen(NH 3-N) loads were estimated.Results showed that COD loads of point source and nonpoint source were 134 958 t/yr and 86 209 t/yr, accounting for 61.02% and 38.98% of total loads, respectively.NH 3-N loads of point source and nonpoint source were 16 739 t/yr and 14 272 t/yr, accounting for 53.98% and 46.02%, respectively.Point source pollution was stronger than nonpoint source pollution in the study area at present.The water quality of upstream was better than that of downstream of the rivers and cities.It is indispensable to treat industrial wastewater and municipal sewage out of point sources, to adopt the best management practices to control diffuse pollutants from agricultural land and urban surface runoff in improving water quality of the Songhua River Basin.The revised S-P model can be successfully used to identify pollution source and quantify point source and nonpoint source loads by calibrating and validating. 展开更多
关键词 ammonia nitrogen chemical oxygen demand nonpoint source pollution point source pollution revised water quality model Songhua River Basin
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Development and application of a two-dimensional water quality model for the Daqinghe River Mouth of the Dianchi Lake 被引量:12
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作者 CHEN Qiuwen TAN Kui +1 位作者 ZHU Chuanbao LI Ruonan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期313-318,共6页
Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi L... Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi Lake, China, a two-dimensional water quality model was developed in the research. The hydrodynamics module was numerically solved by the alternating direction iteration (ADI) method. The parameters of the water quality module were obtained through the in situ experiments and the laboratory analyses that were conducted from 2006 to 2007. The model was calibrated and verified by the observation data in 2007. Among the four modelled key variables, i.e., water level, COD (in CODcr), NH4+-N and PO43-P the minimum value of the coefficient of determination (COD) was 0.69, indicating the model performed reasonably well. The developed model was then applied to simulate the water quality changes at a downstream cross-section assuming that the designed restoration programs were implemented. According to the simulated results, the restoration programs could cut down the loads of COD and PO43-P about 15%. Such a load reduction, unfortunately, would have very little effect on the NH4^+-N removal. Moreover, the water quality at the outlet cross-section would be still in class V (3838-02), indicating more measures should be taken to further reduce the loads. The study demonstrated the capability of water quality models to support aquatic ecosystem restorations. 展开更多
关键词 two-dimensional water quality model parameter estimation restoration program evaluation Dianchi Lake
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3-D Geological Modeling-Concept,Methods and Key Techniques 被引量:17
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作者 PAN Mao LI Zhaoliang +2 位作者 GAO Zhongbo YANG Yang WU Gengyu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第4期1031-1036,共6页
3-D geological modeling plays an increasingly important role in Petroleum Geology, Mining Geology and Engineering Geology. The complexity of geological conditions requires different modeling methods in different situa... 3-D geological modeling plays an increasingly important role in Petroleum Geology, Mining Geology and Engineering Geology. The complexity of geological conditions requires different modeling methods in different situations. This paper summarizes the general concept of geological modeling; compares the characteristics of borehole-based modeling, cross-section based modeling and multi- source interactive modeling; analyses key techniques in 3-D geological modeling; and highlights the main difficulties and directions of future studies. 展开更多
关键词 3-D geological modeling geological interpretation methods of modeling quality of models
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Water Quality Model Establishment for Middle and Lower Reaches of Hanshui River,China 被引量:3
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作者 WANG Qinggai ZHAO Xiaohong +3 位作者 YANG Mushui ZHAO Yue LIU Kun MA Qiang 《Chinese Geographical Science》 SCIE CSCD 2011年第6期646-655,共10页
With the development of industry and agriculture,nitrogen,phosphorus and other nutrients in the Hanshui River greatly increase and eutrophication has become an important threat to the water quality of the Hanshui Rive... With the development of industry and agriculture,nitrogen,phosphorus and other nutrients in the Hanshui River greatly increase and eutrophication has become an important threat to the water quality of the Hanshui River,especially in the middle and lower reaches.The primary objective of this study was to establish the water quality model for the middle and lower reaches of the Hanshui River based on the model of MIKE 11.The main pollutants migration and transformation process could be simulated using the water quality model.The rainfall-runoff model,hy-drodynamic model and water quality model were established using MIKE 11.The pollutants,such as chemical oxygen demand(COD),biochemical oxygen demand(BOD),ammonia nitrogen,nitrate nitrogen,phosphorus,dissolved oxy-gen(DO),were simulated and predicted using the above three models.A set of methods computing non-point source pollution load of the Hanshui River Basin was proposed in this study.The simulated and observed values of COD,BOD5,ammonia,nitrate,DO,and total phosphorus were compared after the parameter calibration of the water quality model.The simulated and observed results match better,thus the model can be used to predict water quality in the fu-ture for the Hanshui River.The pollution trend could be predicted using the water quality model according pollution load generation.It is helpful for government to take effective measures to prevent the water bloom and protect water quality in the river. 展开更多
关键词 rainfall-runoff model hydrodynamic model water quality model Hanshui River MIKE 11
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