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Assessment of Wet Season Precipitation in the Central United States by the Regional Climate Simulation of the WRFG Member in NARCCAP and Its Relationship with Large-Scale Circulation Biases 被引量:1
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作者 Yating ZHAO Ming XUE +2 位作者 Jing JIANG Xiao-Ming HU Anning HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期619-638,共20页
Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss pos... Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss possible causes of biases in a WRF-based RCM with a grid spacing of 50 km,named WRFG,from the North American Regional Climate Change Assessment Program(NARCCAP)in simulating wet season precipitation over the Central United States for a period when observational data are available.The RCM reproduces key features of the precipitation distribution characteristics during late spring to early summer,although it tends to underestimate the magnitude of precipitation.This dry bias is partially due to the model’s lack of skill in simulating nocturnal precipitation related to the lack of eastward propagating convective systems in the simulation.Inaccuracy in reproducing large-scale circulation and environmental conditions is another contributing factor.The too weak simulated pressure gradient between the Rocky Mountains and the Gulf of Mexico results in weaker southerly winds in between,leading to a reduction of warm moist air transport from the Gulf to the Central Great Plains.The simulated low-level horizontal convergence fields are less favorable for upward motion than in the NARR and hence,for the development of moist convection as well.Therefore,a careful examination of an RCM’s deficiencies and the identification of the source of errors are important when using the RCM to project precipitation changes in future climate scenarios. 展开更多
关键词 NARCCAP Central United States PRECIPITATION low-level jet large-scale environment diurnal variation
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Assessing cutter-rock interaction during TBM tunnelling in granite:Large-scale standing rotary cutting tests and 3D DEM simulations
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作者 Xin Huang Miaoyuan Tang +4 位作者 Shuaifeng Wang Yixin Zhai Qianwei Zhuang Chi Zhang Qinghua Lei 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3595-3615,共21页
The widespread utilisation of tunnel boring machines(TBMs)in underground construction engineering requires a detailed investigation of the cutter-rock interaction.In this paper,we conduct a series of largescale standi... The widespread utilisation of tunnel boring machines(TBMs)in underground construction engineering requires a detailed investigation of the cutter-rock interaction.In this paper,we conduct a series of largescale standing rotary cutting tests on granite in conjunction with high-fidelity numerical simulations based on a particle-type discrete element method(DEM)to explore the effects of key cutting parameters on the TBM cutter performance and the distribution of cutter-rock contact stresses.The assessment results of cutter performance obtained from the cutting tests and numerical simulations reveal similar dependencies on the key cutting parameters.More specifically,the normal and rolling forces exhibit a positive correlation with penetration but are slightly influenced by the cutting radius.In contrast,the side force decreases as the cutting radius increases.Additionally,the side force shows a positive relationship with the penetration for smaller cutting radii but tends to become negative as the cutting radius increases.The cutter's relative effectiveness in rock breaking is significantly impacted by the penetration but shows little dependency on the cutting radius.Consequently,an optimal penetration is identified,leading to a low boreability index and specific energy.A combined Hertz-Weibull function is developed to fit the cutter-rock contact stress distribution obtained in DEM simulations,whereby an improved CSM(Colorado School of Mines)model is proposed by replacing the original monotonic cutting force distribution with this combined Hertz-Weibull model.The proposed model outperforms the original CSM model as demonstrated by a comparison of the estimated cutting forces with those from the tests/simulations.The findings from this work that advance our understanding of TBM cutter performance have important implications for improving the efficiency and reliability of TBM tunnelling in granite. 展开更多
关键词 large-scale standing rotary cutting test Discrete element method(DEM)simulation Cutter-rock interaction Improved CSM(Colorado School of Mines) model Cutting force
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Side Effects of Large-Scale Assessments in Education 被引量:3
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作者 Trina E.Emler Yong Zhao +2 位作者 Jiayi Deng Danqing Yin Yurou Wang 《ECNU Review of Education》 2019年第3期279-296,共18页
Purpose:In line with a recent call for side effects research in education,this article aims to synthesize the major concerns that have been raised in the literature concerning large-scale assessments(LSAs)in education... Purpose:In line with a recent call for side effects research in education,this article aims to synthesize the major concerns that have been raised in the literature concerning large-scale assessments(LSAs)in education.Design/Approach/Methods:The researchers endeavored to complete a deep review of the literature on LSAs to synthesize the reported side effects.The review was synthesized thematically to understand and report the consequences of the ongoing push for the use of LSA in education.Findings:Thematic analysis indicated overarching side effects of LSA in education.We discuss why negative side effects exist and present evidence of the most commonly observed side effects of LSA in education,including distorting education,exacerbating inequity and injustice,demoralization of professionals,ethical corruption,and stifling of innovation in education.Originality/Value:While concerns about the use and misuse of LSA in education are not new and have been discussed widely in the literature,rarely have they been discussed as inherent qualities and consequences of LSAs that can do harm to education. 展开更多
关键词 INEQUITY large-scale assessments side effects
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Construction of Risk Assessment Application Model of Epidemic Disease in Large-scale Pig Farms 被引量:1
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作者 谭业平 刘强 +3 位作者 胡肄农 郁达威 何孔旺 陆昌华 《Agricultural Science & Technology》 CAS 2016年第9期2124-2126,共3页
The application model of epidemic disease assessment technology for Web-based large-scale pig farm was expounded from the identification of epidemic disease risk factors, construction of risk assessment model and deve... The application model of epidemic disease assessment technology for Web-based large-scale pig farm was expounded from the identification of epidemic disease risk factors, construction of risk assessment model and development of risk assessment system. The assessed pig farm uploaded the epidemic disease risk data information through on-line answering evaluating questionnaire to get the immediate evaluation report. The model could enhance the risk communication between pig farm veterinarian, manager and veterinary experts to help farm system understand and find disease risk factors, assess and report the potential high risk items of the pig farm in the three systems of engineering epidemic disease prevention technology, biological safety and immune monitoring, and promote the improvement and perfection of epidemic disease prevention and control measures. 展开更多
关键词 large-scale pig farm Risk assessment of epidemic disease Model construction
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A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization 被引量:1
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作者 Sheng Qi Rui Wang +3 位作者 Tao Zhang Xu Yang Ruiqing Sun Ling Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1342-1357,共16页
Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.... Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.As a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec separately.Nevertheless,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables Mask.However,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is optimized.In data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between data.Inspired by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these SLMOPs.TELSO mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast convergence.Experi-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed. 展开更多
关键词 Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.
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Large-Scale Assessments,Personalized Learning,and Creativity:Paradoxes and Possibilities 被引量:1
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作者 Ronald A.Beghetto 《ECNU Review of Education》 2019年第3期311-327,共17页
Purpose:This article,based on an invited talk,aims to explore the relationship among large-scale assessments,creativity and personalized learning.Design/Approach/Methods:Starting with the working definition of large-s... Purpose:This article,based on an invited talk,aims to explore the relationship among large-scale assessments,creativity and personalized learning.Design/Approach/Methods:Starting with the working definition of large-scale assessments,creativity,and personalized learning,this article identified the paradox of combining these three components together.As a consequence,a logic mode of large-scale assessment and creativity expressions is illustrated,along with an exploration of new possibilities.Findings:Smarter design of large-scale assessments is needed.Firstly,we need to assess creative learning at the individual level,so complex tasks with high uncertainty should be presented to students.Secondly,additional process and experiential data while students are working on problems need to be captured.Thirdly,the human-artificial intelligence(AI)augmented scoring should be explored,developed,and refined.Originality/Value:This article addresses the drawbacks of current large-scale assessments and explores possibilities for combining assessment with creativity and personalized learning.A logic model illustrating variations necessary for creative learning and considerations and cautions for designing large-scale assessments are also provided. 展开更多
关键词 Creative expression creative learning CREATIVITY large-scale assessments personalized learning
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Machine Learning-Based Decision-Making Mechanism for Risk Assessment of Cardiovascular Disease 被引量:1
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作者 Cheng Wang Haoran Zhu Congjun Rao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期691-718,共28页
Cardiovascular disease(CVD)has gradually become one of the main causes of harm to the life and health of residents.Exploring the influencing factors and risk assessment methods of CVD has become a general trend.In thi... Cardiovascular disease(CVD)has gradually become one of the main causes of harm to the life and health of residents.Exploring the influencing factors and risk assessment methods of CVD has become a general trend.In this paper,a machine learning-based decision-making mechanism for risk assessment of CVD is designed.In this mechanism,the logistics regression analysismethod and factor analysismodel are used to select age,obesity degree,blood pressure,blood fat,blood sugar,smoking status,drinking status,and exercise status as the main pathogenic factors of CVD,and an index systemof risk assessment for CVD is established.Then,a two-stage model combining K-means cluster analysis and random forest(RF)is proposed to evaluate and predict the risk of CVD,and the predicted results are compared with the methods of Bayesian discrimination,K-means cluster analysis and RF.The results show that thepredictioneffect of theproposedtwo-stagemodel is better than that of the comparedmethods.Moreover,several suggestions for the government,the medical industry and the public are provided based on the research results. 展开更多
关键词 CVD influencing factors risk assessment machine learning two-stage model
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Risk assessment of oil and gas investment environment in countries along the Belt and Road Initiative 被引量:1
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作者 Bao-Jun Tang Chang-Jing Ji +3 位作者 Yu-Xian Zheng Kang-Ning Liu Yi-Fei Ma Jun-Yu Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1429-1443,共15页
With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of inv... With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for China's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative. 展开更多
关键词 Belt and Road Initiative Oil and Gas Investment Risk assessment
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Risk Assessment of Deep-Water Horizontal X-Tree Installation 被引量:1
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作者 MENG Wen-bo FU Guang-ming +3 位作者 HUANG Yi LIU Shu-jie HUANG Liang GAOYong-hai 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期210-220,共11页
Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a ... Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a modular risk evaluation model based on a fuzzy fault tree.First,through the analysis of the main process oftree down and combining the Offshore&Onshore Reliability Data(OREDA)failure statistics and the operation procedure and the data provided by the job,the fault tree model of risk analysis of the tree down installation was established.Then,by introducing the natural language of expert comprehensive evaluation and combining fuzzy principles,quantitative analysis was carried out,and the fuzzy number was used to calculate the failure probability of a basic event and the occurrence probability of a top event.Finally,through a sensitivity analysis of basic events,the basic events of top events significantly affected were determined,and risk control and prevention measures for the corresponding high-risk factors were proposed for subsea horizontal X-tree down installation. 展开更多
关键词 subsea horizontal X-tree risk assessment fuzzy fault tree modular risk evaluation model
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Effect of a comprehensive geriatric assessment nursing intervention model on older patients with diabetes and hypertension 被引量:1
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作者 Dong-Ying Bao Lin-Yan Wu Qi-Yan Cheng 《World Journal of Clinical Cases》 SCIE 2024年第20期4065-4073,共9页
BACKGROUND The Comprehensive Geriatric Assessment(CGA)was introduced late in China and is primarily used for investigating and evaluating health problems in older adults in outpatient and community settings.However,th... BACKGROUND The Comprehensive Geriatric Assessment(CGA)was introduced late in China and is primarily used for investigating and evaluating health problems in older adults in outpatient and community settings.However,there are few reports on its application in hospitalized patients,especially older patients with diabetes and hypertension.AIM To explore the nursing effect of CGA in hospitalized older patients with diabetes and hypertension.METHODS We performed a retrospective single-center analysis of patients with comorbid diabetes mellitus and hypertension who were hospitalized and treated in the Jiangyin Hospital of Traditional Chinese Medicine between September 2020 and June 2022.Among the 80 patients included,40 received CGA nursing interventions(study group),while the remaining 40 received routine nursing care(control group).The study group's comprehensive approach included creating personalized CGA profiles,multidisciplinary assessments,and targeted inter-ventions in areas,such as nutrition,medication adherence,exercise,and mental health.However,the control group received standard nursing care,including general and medical history collection,fall prevention measures,and regular patient monitoring.After 6 months of nursing care implementation,we evaluated the effectiveness of the interventions,including assessments of blood glucose levels fasting blood glucose,2-h postprandial blood glucose,and glycated hemoglobin,type A1c(HbA1c);blood pressure indicators such as diastolic blood pressure(DBP)and systolic blood pressure(SBP);quality of life as measured by the 36-item Short Form Survey(SF-36)questionnaire;and treatment adherence.RESULTS After 6 months,the nursing outcomes indicated that patients who underwent CGA nursing interventions experienced a significant decrease in blood glucose indicators,such as fasting blood glucose,2-h postprandial blood glucose,and HbA1c,as well as blood pressure indicators,including DBP and SBP,compared with the control group(P<0.05).Quality of life assessments,including physical health,emotion,physical function,overall health,and mental health,showed marked improvements compared to the control group(P<0.05).In the study group,38 patients adhered to the clinical treatment requirements,whereas only 32 in the control group adhered to the clinical treatment requirements.The probability of treatment adherence among patients receiving CGA nursing interventions was higher than that among patients receiving standard care(95%vs 80%,P<0.05).CONCLUSION The CGA nursing intervention significantly improved glycemic control,blood pressure management,and quality of life in hospitalized older patients with diabetes and hypertension,compared to routine care. 展开更多
关键词 Comprehensive geriatric assessment DIABETES HYPERTENSION NURSING Quality of life COMPLIANCE
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Enhancing Evolutionary Algorithms With Pattern Mining for Sparse Large-Scale Multi-Objective Optimization Problems
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作者 Sheng Qi Rui Wang +3 位作者 Tao Zhang Weixiong Huang Fan Yu Ling Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1786-1801,共16页
Sparse large-scale multi-objective optimization problems(SLMOPs)are common in science and engineering.However,the large-scale problem represents the high dimensionality of the decision space,requiring algorithms to tr... Sparse large-scale multi-objective optimization problems(SLMOPs)are common in science and engineering.However,the large-scale problem represents the high dimensionality of the decision space,requiring algorithms to traverse vast expanse with limited computational resources.Furthermore,in the context of sparse,most variables in Pareto optimal solutions are zero,making it difficult for algorithms to identify non-zero variables efficiently.This paper is dedicated to addressing the challenges posed by SLMOPs.To start,we introduce innovative objective functions customized to mine maximum and minimum candidate sets.This substantial enhancement dramatically improves the efficacy of frequent pattern mining.In this way,selecting candidate sets is no longer based on the quantity of nonzero variables they contain but on a higher proportion of nonzero variables within specific dimensions.Additionally,we unveil a novel approach to association rule mining,which delves into the intricate relationships between non-zero variables.This novel methodology aids in identifying sparse distributions that can potentially expedite reductions in the objective function value.We extensively tested our algorithm across eight benchmark problems and four real-world SLMOPs.The results demonstrate that our approach achieves competitive solutions across various challenges. 展开更多
关键词 Evolutionary algorithms pattern mining sparse large-scale multi-objective problems(SLMOPs) sparse large-scale optimization.
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Lead, Zinc and Iron Pollutants Load Assessment in Selected Rivers in Southern Nigeria: Implications for Domestic Uses
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作者 Ochuko Ushurhe Ozabor Famous +1 位作者 Ezekiel Ovuokerie Gunn Sapere-Obi Martha Ladebi 《Journal of Water Resource and Protection》 CAS 2024年第1期58-82,共25页
The aim of the study is to comparatively assess the concentrations of lead, zinc and iron in Rivers Ase, Warri and Ethiope, in Nigeria. Monthly water samples were collected from six randomly selected sites along the r... The aim of the study is to comparatively assess the concentrations of lead, zinc and iron in Rivers Ase, Warri and Ethiope, in Nigeria. Monthly water samples were collected from six randomly selected sites along the rivers course. 72 water samples were collected from each river at 0 - 15 cm depths. Samples were analysed based on the standard methods recommended by the WHO for testing lead, zinc and iron. The assessment of the water quality was done using the Water Quality Index (WQI) of the Canadian Council of Ministers of the Environment (CCME-WQI). While hypotheses were tested using ANOVA. Findings indicated that CCME-WQI values were 47.3, 66.52 and 78.7. This meant that the water quality of River Ase is impaired and departed from desirable levels, while that of Warri and Ethiope were considered to occasionally be impaired and depart from desirable levels. The ANOVA model showed that there is a significant variation in heavy metal load in the selected rivers at P < 0.05. River water was put to domestic uses such as drinking (20.5%) preparing food (17.8%), bathing (19.8%), washing clothes and dishes (21.3%), brushing teeth (13.3%), and catering for domestic animals (7.5%). Poverty (49.5%) was the major reason for the use of river water for domestic purposes. The locals highlighted that they usually suffer from cholera (26.8%), diarrhoea (25.8%), dysentery (24%) and typhoid (23.5%) as a result of using the river water. The study recommended routine monitoring of anthropogenic and geologic activities, testing of the water regularly amongst others. 展开更多
关键词 assessment Water-Quality-Index DOMESTIC Heavy-Metals
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Large-scale model testing of high-pressure grouting reinforcement for bedding slope with rapid-setting polyurethane
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作者 ZHANG Zhichao TANG Xuefeng +2 位作者 LIU Kan YE Longzhen HE Xiang 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3083-3093,共11页
Bedding slope is a typical heterogeneous slope consisting of different soil/rock layers and is likely to slide along the weakest interface.Conventional slope protection methods for bedding slopes,such as retaining wal... Bedding slope is a typical heterogeneous slope consisting of different soil/rock layers and is likely to slide along the weakest interface.Conventional slope protection methods for bedding slopes,such as retaining walls,stabilizing piles,and anchors,are time-consuming and labor-and energy-intensive.This study proposes an innovative polymer grout method to improve the bearing capacity and reduce the displacement of bedding slopes.A series of large-scale model tests were carried out to verify the effectiveness of polymer grout in protecting bedding slopes.Specifically,load-displacement relationships and failure patterns were analyzed for different testing slopes with various dosages of polymer.Results show the great potential of polymer grout in improving bearing capacity,reducing settlement,and protecting slopes from being crushed under shearing.The polymer-treated slopes remained structurally intact,while the untreated slope exhibited considerable damage when subjected to loads surpassing the bearing capacity.It is also found that polymer-cemented soils concentrate around the injection pipe,forming a fan-shaped sheet-like structure.This study proves the improvement of polymer grouting for bedding slope treatment and will contribute to the development of a fast method to protect bedding slopes from landslides. 展开更多
关键词 POLYURETHANE Bedding slope GROUTING Slope protection large-scale model test
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Development of Localized Assessment of Municipal Wastewater Disposal Risks
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作者 Frederick Bloetscher Daniel E. Meeroff Brittanney Adelmann 《Journal of Water Resource and Protection》 CAS 2024年第6期395-413,共19页
A means to develop a comparative assessment of the risks of available wastewater effluent disposal options on a local scale needs to be developed to help local decision-makers make decisions on options such as direct ... A means to develop a comparative assessment of the risks of available wastewater effluent disposal options on a local scale needs to be developed to help local decision-makers make decisions on options such as direct or indirect potable reuse options. These options have garnered more interest as a result of water supply limitations in many urban areas. This risk assessment was developed from a risk assessment developed at the University of Miami in 2001 and Florida Atlantic University (FAU) in 2023. Direct potable reuse and injection wells were deemed to have the lowest risk in the most recent study by FAU. However, the injection well option may not be available everywhere. As a result, a more local means to assess exposure risk is needed. This paper outlines the process to evaluate the public health risks associated with available disposal alternatives which may be very limited in some areas. The development of exposure pathways can help local decision-makers define the challenges, and support later expert level analysis upon which public health decisions are based. 展开更多
关键词 Potable Reuse WASTEWATER Effluent Disposal Risk Risk assessment
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A risk assessment method considering risk attributes and work safety informational needs and its application
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作者 Cong Luo Yunsheng Zhao Ke Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期253-262,共10页
The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and systematicness.Risk assessment needs to evo... The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and systematicness.Risk assessment needs to evolve to address the existing and future challenges by considering the new demands and advancements in safety management.The study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety management.The methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk factors.Subsequently,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision needs.And in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety management.The findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility. 展开更多
关键词 Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system
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Air Quality Assessment of Ubeji Community near Petroleum-Related Activities
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作者 Adedoyin Olubunmi Bankole Akinyemi Olufemi Ogunkeyede +5 位作者 Oluwafunmilayo Mary Haruna Harrison Agboro Prince Alex Ekhorutomwen Osasenaga Israel Otuomagie Christabel Ifuwe Efe Jeffery Isukuru 《Open Journal of Air Pollution》 2024年第2期57-71,共15页
The escalating global concern over air pollution requires rigorous investigations. This study assesses air quality near residential areas affected by petroleum-related activities in Ubeji Community, utilizing Aeroqual... The escalating global concern over air pollution requires rigorous investigations. This study assesses air quality near residential areas affected by petroleum-related activities in Ubeji Community, utilizing Aeroqual handheld mobile multi-gas monitors and air quality multi-meters. Air sampling occurred on three distinct days using multi-gas monitors and meters, covering parameters such as CO, NO2, CH4, NH3, VOCs, Particulate Matter, Temperature, Relative Humidity, and Air Quality Index. Soil and plant samples were collected and analyzed for physicochemical and organic components. Air pollutant concentrations showed significant fluctuations. Carbon monoxide (CO) ranged from 0.00 to 3.22 ppm, NO2 from 0.00 to 0.10 ppm, CH4 from 4.00 to 2083 ppm, NH3 from 371 to 5086 ppm, and VOCs from 414 to 6135 ppm. Soil analysis revealed low total nitrogen, and undetected BTEX levels. Plant samples displayed a pH range of 7.72 to 9.45. CO concentrations, although below WHO limits, indicated potential vehicular and industrial influences. Fluctuations in NO2 and CH4 were linked to traffic, industrial activities, and gas flaring. NH3 levels suggested diverse pollution sources. The result in this study highlights the dynamic nature of air pollution in Ubeji community, emphasizing the urgent need for effective pollution control measures. Although CO concentrations were within limits, continuous monitoring is essential. Elevated NO2 levels gave information on the impact of industrial activities, while high CH4 concentrations may be associated with gas flaring and illegal refining. The study recommends comprehensive measures and collaborative efforts to address these complex issues, safeguarding both the environment and public health. This study shows the potential synergy between air quality sensors and plants for holistic environmental health assessments, offering valuable insights for environmental assessments and remediation endeavours. The findings call for stringent regulations and collaborative efforts to address air pollution in Ubeji community comprehensively. 展开更多
关键词 Air Quality assessment BIOINDICATORS Ubeji Community Pollution assessment
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Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics
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作者 Siwei Li Liang Yue +1 位作者 Xiangyu Kong Chengshan Wang 《Global Energy Interconnection》 EI CSCD 2024年第3期313-323,共11页
This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online ide... This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective. 展开更多
关键词 Load aggregation Regional large-scale Online recognition Feature extraction method
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A semantic vector map-based approach for aircraft positioning in GNSS/GPS denied large-scale environment
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作者 Chenguang Ouyang Suxing Hu +6 位作者 Fengqi Long Shuai Shi Zhichao Yu Kaichun Zhao Zheng You Junyin Pi Bowen Xing 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期1-10,共10页
Accurate positioning is one of the essential requirements for numerous applications of remote sensing data,especially in the event of a noisy or unreliable satellite signal.Toward this end,we present a novel framework... Accurate positioning is one of the essential requirements for numerous applications of remote sensing data,especially in the event of a noisy or unreliable satellite signal.Toward this end,we present a novel framework for aircraft geo-localization in a large range that only requires a downward-facing monocular camera,an altimeter,a compass,and an open-source Vector Map(VMAP).The algorithm combines the matching and particle filter methods.Shape vector and correlation between two building contour vectors are defined,and a coarse-to-fine building vector matching(CFBVM)method is proposed in the matching stage,for which the original matching results are described by the Gaussian mixture model(GMM).Subsequently,an improved resampling strategy is designed to reduce computing expenses with a huge number of initial particles,and a credibility indicator is designed to avoid location mistakes in the particle filter stage.An experimental evaluation of the approach based on flight data is provided.On a flight at a height of 0.2 km over a flight distance of 2 km,the aircraft is geo-localized in a reference map of 11,025 km~2using 0.09 km~2aerial images without any prior information.The absolute localization error is less than 10 m. 展开更多
关键词 large-scale positioning Building vector matching Improved particle filter GPS-Denied Vector map
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Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation 被引量:1
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作者 Chang Yang Yong-bo Tie +3 位作者 Xian-zheng Zhang Yan-feng Zhang Zhi-jie Ning Zong-liang Li 《China Geology》 CAS CSCD 2024年第2期248-263,共16页
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff... Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events. 展开更多
关键词 Landslide Debris flow Hazard assessment Numerical simulation OpenLISEM Prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully Sichuan province Geological hazards survey engineering
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Clinical validation of the early embryo viability assessment system: Analysis for the blastocyst morphology and pregnancy outcomes
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作者 Vu D Hop An M Cuong +3 位作者 Phi T T Anh Nguyen T L Huong Le Hoang Nguyen V Hanh 《Asian pacific Journal of Reproduction》 CAS 2024年第5期219-227,共9页
Objective:To determine the relationship between the early embryo viability assessment(EEVA)and blastocyst morphological parameters and pregnancy outcomes.Methods:This retrospective cohort study was conducted on 291 in... Objective:To determine the relationship between the early embryo viability assessment(EEVA)and blastocyst morphological parameters and pregnancy outcomes.Methods:This retrospective cohort study was conducted on 291 intracytoplasmic sperm injection cycles including 2522 embryos with indications of prolonging embryo culture to the blastocyst stage in the Genea embryo review incubator,and 511 single vitrified-warmed blastocyst transfer cycles from January 2020 to June 2023.The EEVA system produced an EEVA score from E1(best)to E5(worse)for the potential of blastocyst formation.Blastocyst morphology was evaluated.The association between the EEVA score and each type of blastocyst morphology,implantation rate,clinical pregnancy,and ongoing pregnancy were assessed using generalized estimating equations.Results:The inner cell mass A(ICM A),trophectoderm A(TE A),blastocoele expansion degree of 3,4,5,6,7 rates were higher with lower the EEVA score.The adjusted odd ratio(aOR)(E5 vs E1)was 0.3 for ICM A,0.174 for TE A and 0.210 for BL3,4,5,6,7(all P<0.001),suggesting a significant association between lower EEVA scores and improved embryo quality.The implantation,clinical pregnancy,and ongoing pregnancy rate were also higher with lower the EEVA score.The aOR of E5 vs E1 was 0.245 for implantation,0.185 for clinical pregnancy and 0.200 for ongoing pregnancy rate(P<0.001).Conclusions:There were associations between blastocyst morphology,pregnancy outcome and EEVA scores.The good blastocyst morphology and pregnancy outcomes are higher with lower the EEVA score. 展开更多
关键词 Automated embryo assessment BLASTOCYST Early embryo viability assessment Genea embryo review incubator MORPHOLOGY Pregnancy outcomes Timelapse
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