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Distribution, health and ecological risk assessments of trace elements in Nigerian oil sands
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作者 Odunayo T.Ore Festus M.Adebiyi 《Acta Geochimica》 EI CAS CSCD 2024年第1期59-71,共13页
The Nigerian oil sands represent the largest oil sand deposit in Africa, yet there is little published information on the distribution and potential health and ecological risks of trace elements in the oil resource. I... The Nigerian oil sands represent the largest oil sand deposit in Africa, yet there is little published information on the distribution and potential health and ecological risks of trace elements in the oil resource. In the present study, we investigated the distribution pattern of 18trace elements(including biophile and chalcophile elements) as well as the estimated risks associated with exposure to these elements. The results of the study indicated that Fe was the most abundant element, with a mean concentration of 22,131 mg/kg while Br had the lowest mean concentration of 48 mg/kg. The high occurrence of Fe and Ti suggested a possible occurrence of ilmenite(Fe TiO_(3)) in the oil sands. Source apportionment using positive matrix factorization showed that the possible sources of detected elements in the oil sands were geogenic, metal production, and crustal. The contamination factor, geo-accumulation index, modified degree of contamination, pollution load index, and Nemerow pollution index indicated that the oil sands are heavily polluted by the elements. Health risk assessment showed that children were relatively more susceptible to the potentially toxic elements in the oil sands principally via ingestion exposure route(HQ > 1E-04). Cancer risks from inhalation are unlikely due to CR < 1E-06 but ingestion and dermal contact pose severe risks(CR > 1E-04). The high concentrations of the elements pose serious threats due to the potential for atmospheric transport, bioaccessibility, and bioavailability. 展开更多
关键词 Biophile Chalcophile Oil sand risk assessment Trace element
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Geochemical signatures and human health risk evaluation of rare earth elements in soils and plants of the northeastern Qinghai-Tibet Plateau,China
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作者 LI Leiming WU Jun +2 位作者 LU Jian ZHANG Xiying XU Juan 《Journal of Arid Land》 SCIE CSCD 2022年第11期1258-1273,共16页
Information on rare earth elements(REEs)in soils and plants of the Qinghai-Tibet Plateau is very limited.Therefore,in this study,we performed field sampling to explore the geochemical signatures and human health risk ... Information on rare earth elements(REEs)in soils and plants of the Qinghai-Tibet Plateau is very limited.Therefore,in this study,we performed field sampling to explore the geochemical signatures and human health risk of REEs in soils and plants of the northeastern Qinghai-Tibet Plateau,China.A total of 127 soil samples and 127 plant samples were collected from the northeastern Qinghai-Tibet Plateau to acquire the geochemical signatures and related human health risks of REEs.The mean total concentrations of REEs in soils and plants of the study area reached 178.55 and 10.06 mg/kg,respectively.The light REEs in soils and plants accounted for 76%and 77%of the total REEs,respectively.REEs showed significantly homogenous distribution in soils but inhomogeneous distribution in plants of the study area.Characteristic parameters indicated that light REEs were enriched and fractionated significantly,while heavy REEs were moderately fractionated in soils and plants.REEs in soils and plants showed significantly negative Europium anomaly.Cerium showed slightly positive anomaly in plants and slight anomaly in soils.The normalized distribution patterns of REEs were generally similar in the analyzed soils and the corresponding plants of the study area.The average bio-concentration factor of REEs ranged from 0.0478(Scandium)to 0.0604(Europium),confirming a small accumulation of REEs by plants.Health risks caused by REEs in soils and plants were negligible,while risks for adults were lower than those for children.This study provides important information on REEs in soils and plants of the northeastern Qinghai-Tibet Plateau. 展开更多
关键词 rare earth elements geochemical signatures human health risk carcinogenic risk bio-concentration factor Qinghai-Tibet Plateau
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Co-Contamination of Arsenic and Other Trace Elements (Hg, Pb, Al, Fe, Cr, Ni, and Cd) in the Rafsanjan Plain Alluvial Aquifer SE of Iran and Arsenic Risk Assessment
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作者 Mehdi Honarmand Sahar Khajehpour +1 位作者 Hadi Shahriari Mahdie Hoseinjani 《Open Journal of Geology》 2017年第11期1710-1723,共14页
Assessing the concentration of trace elements in aquifers is increasingly subjected to study in Iran due to the lack of groundwater resources. This study was undertaken with the objective of determining trace elements... Assessing the concentration of trace elements in aquifers is increasingly subjected to study in Iran due to the lack of groundwater resources. This study was undertaken with the objective of determining trace elements in the alluvial aquifer located in the southern part of the Rafsanjan plain, Kerman province, Iran. The total of 73 groundwater samples from individual water wells were analyzed by atomic absorption spectroscopy (AAS). Results showed that the levels of As, Hg, Pb, Al, Fe, Cr, Ni, and Cd elements were above the World Health Organization standards for drinking-water in some parts of the plain. Thus, statistical data analyses and spatial distribution interpretation were performed to identify the main sources of the pollution. A health risk assessment model derived from US environmental protection agency was applied to calculate the cumulative exposure to As as well as toxic and carcinogenic risks caused by drinking contaminated raw groundwater. Results show that residents of some part of region may suffer from significant adverse toxic health impacts and are exposed to drinking water with As concentrations. 展开更多
关键词 ARSENIC Health risk TRACE elements Rafsanjan PLAIN GROUNDWATER Pollution
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Seasonal variations and health risk assessment of trace elements in the Badigad River,lesser Himalayas,Nepal
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作者 Ramesh Raj Pant Kiran Bishwakarma +4 位作者 Kshitiz Kandel Sudip Poudel Jharana Nepal Bhanu Bhakta Neupane Virendra Bahadur Singh 《Acta Geochimica》 EI CAS CSCD 2023年第4期689-703,共15页
The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the less... The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the lesser Himalayas of Nepal.In total,44 water samples were collected from 22 different sites during the pre-monsoon and monsoon seasons,and 25 TEs were analyzed.Correlation matrix and principal component analysis(PCA)were used to analyze the potential relationship between the measured TEs and their source tracking.Furthermore,the water quality index(WQI),metal index(MI),and cancer index(CI)were evaluated.The TEs content in all samples were found to be within the WHO recommended guideline for drinking and domestic purposes.The dominancy order of the TEs was observed as Sr>Ba>Li>Rb>Zn>Cr>Sc>Mn>Ti>Cu>As>Ni>Co>U>V>Pb>Cs>Ga>Y>Tl>Th>Zr>Bi>Cd>Nb.The PCA analysis suggested that TEs could have natural,anthropogenic,and mixed origins.The WQI indicated that the river water is safe from a human health perspective.The MI suggested that Badigad River can be considered safer for drinking purposes,and the cancer index(CI)showed that all the reported TEs are at low-risk levels.The findings of this study could be useful for government agencies in developing more sustainable water management policies in the region.However,it is suggested that further investigations should be conducted in terms of other hydrogeochemical variables,including major ions,at spatiotemporal levels for the sustainability of the river basin. 展开更多
关键词 Trace elements Water quality Health risk assessment Multivariate analysis Badigad River
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Working With Immigrant Children and Adolescents at Risk:Mentors’Use of the Elements Way
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作者 Gila Cohen Zilka 《Psychology Research》 2018年第7期308-321,共14页
The study was designed to examine the effectiveness of mentors’work with immigrant children and adolescents at risk,using the Elements Way,an educational model designed to facilitate achievement of goals and transfor... The study was designed to examine the effectiveness of mentors’work with immigrant children and adolescents at risk,using the Elements Way,an educational model designed to facilitate achievement of goals and transformation.The three central elements of the method are positive communication(speaking the language of love),acceptance,and connecting with one’s strength.This mixed-method study was conducted in 2012-2015,on a sample of 640 mentors working with 3,350 immigrantchildren in Israel.Improvement has been demonstrated in the personal,social,and emotional functioning of the children and youths,as well as in their academic achievement and especially language acquisition.Significant differences were found in the mentors’work with the children. 展开更多
关键词 IMMIGRANT CHILDREN CHILDREN at risk mentors interaction the elements WAY wellbeing
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Effect of Exposure to Trace Elements in the Soil on the Prevalence of Neural Tube Defects in a High-Risk Area of China 被引量:9
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作者 HUANG Jing WU JiLei +4 位作者 LI TieJun SONG XinMing ZHANG BingZi ZHANG PingWen ZHENG XiaoYing 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第2期94-101,共8页
Objective Our objective is to build a model that explains the association between the exposure to trace elements in the soil and the risk of neural tube defects. Methods We built a function with different parameters t... Objective Our objective is to build a model that explains the association between the exposure to trace elements in the soil and the risk of neural tube defects. Methods We built a function with different parameters to describe the effects of trace elements on neural tube defects. The association between neural tube defects and trace element levels was transformed into an optimization problem using the maximum likelihood method. Results Tin, lead, nickel, iron, copper, and aluminum had typical layered effects (dosage effects) on the prevalence of neural tube defects. Arsenic, selenium, zinc, strontium, and vanadium had no effect, and molybdenum had one threshold value that affected the prevalence of birth defects. Conclusion As an exploratory research work, our model can be used to determine the direction of the effect of the trace element content of cultivated soil on the risk of neural tube defects, which shows the clues by the dosage effect of their toxicological characteristics. Based on our findings, future biogeochemical research should focus on the direct effects of trace elements on human health. 展开更多
关键词 Trace element Neural tube defects risk factors identification Poisson model Maximum likelihood estimation
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Groundwater pollution and human health risk based on Monte Carlo simulation in a typical mining area in Northern Anhui Province,China 被引量:4
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作者 Huili Qiu Herong Gui +1 位作者 Pei Fang Guangping Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第5期1118-1129,共12页
The main objective of this study was to evaluate eight kinds of trace element pollutants in groundwater from a typical coal mine area,and carry out a corresponding health risk assessment for the local populace.To do t... The main objective of this study was to evaluate eight kinds of trace element pollutants in groundwater from a typical coal mine area,and carry out a corresponding health risk assessment for the local populace.To do this,34 shallow groundwater(SG)samples and 18 mid-layer groundwater(MG)samples were collected from the Sulin mining area.To minimize the uncertainties in the health risk assessment,this paper relied on Monte Carlo simulations and sensitivity analysis.The results revealed that Sr and Mn contents exceeded their corresponding WHO(Guidelines for drinking water quality,4th edn.Geneva,2011)guidelines and Chinese groundwater standards(GB/T14848-2017),while the other analyzed trace elements remain below those threshold values.The calculated hazard quotient and hazard index values for adults from ingestion exposure to SG and MG were well below the threshold limit of 1.Probabilistic simulations further show that the total cancer risk value above the limit of 1×10^(-6) is 0%for SG and 29.39%for MG.Sensitivity analysis identified the Sr and Cr contents as the most relevant element variables affecting the probabilistic non-carcinogenic and carcinogenic risk values in the model,respectively. 展开更多
关键词 Health risk assessment Trace elements Monte Carlo simulation Sensitivity analysis Mining area
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Analysis and evaluation of enterprise risk management capability elements 被引量:1
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作者 Liu, Weiwei Wang, Jun Shi, Chunsheng 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期77-81,共5页
Research on enterprise risk management capability is conducted with a view of discerning and processing risks, in which an evaluation index system and an evaluation model of enterprise risk management capabilities are... Research on enterprise risk management capability is conducted with a view of discerning and processing risks, in which an evaluation index system and an evaluation model of enterprise risk management capabilities are constructed. The risk management capability consists of four aspects, i.e. risk identification capability, risk assessment capability, risk planning capability and risk control capability. Risk identification and assessment capabilities reflect the level of enterprises on finding and analyzing risks efficiently, while risk planning and control capabilities reflect the level of enterprises on resolving risks effectively. Each of capabilities is then further divided into more detailed elements based on the characteristics of enterprise development for a quantitative analysis of enterprise risk management capability. The approach adopted is a quantitative technique based on the use of fuzzy comprehensive evaluation. Finally, a case is pulled in to illustrate the feasibility of the method from an empirical perspective. This study is expected to be helpful for enterprises in cultivating their core capabilities. 展开更多
关键词 evaluation index system capability elements risk management fuzzy comprehensive evaluation
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Rapid detection and risk assessment of soil contamination at lead smelting site based on machine learning
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作者 Sheng-guo XUE Jing-pei FENG +5 位作者 Wen-shun KE Mu LI Kun-yan QIU Chu-xuan LI Chuan WU Lin GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期3054-3068,共15页
A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model cor... A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model correction coefficients.The eXtreme Gradient Boosting(XGBoost)model was used to fit the relationship between the content of heavy metals and environment characteristics to evaluate the soil ecological risk of the smelting site.The results demonstrated that the generalized prediction model developed for Pb,Cd,and As was highly accurate with fitted coefficients(R^(2))values of 0.911,0.950,and 0.835,respectively.Topsoil presented the highest ecological risk,and there existed high potential ecological risk at some positions with different depths due to high mobility of Cd.Generally,the application of machine learning significantly increased the accuracy of pXRF measurements,and identified key environmental factors.The adapted potential ecological risk assessment emphasized the need to focus on Pb,Cd,and As in future site remediation efforts. 展开更多
关键词 smelting site potentially toxic elements X-ray fluorescence potential ecological risk machine learning
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Integrated evaluation system under randomness and fuzziness for groundwater contamination risk assessment in a little town, Central China 被引量:2
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作者 祝慧娜 袁兴中 +4 位作者 梁婕 刘永德 尹娟 江洪炜 黄华军 《Journal of Central South University》 SCIE EI CAS 2014年第3期1044-1050,共7页
An integrated evaluation system under randomness and fuzziness was developed in this work to systematically assess the risk of groundwater contamination in a little town, Central China. In this system, randomness of t... An integrated evaluation system under randomness and fuzziness was developed in this work to systematically assess the risk of groundwater contamination in a little town, Central China. In this system, randomness of the parameters and the fuzziness of the risk were considered simultaneously, and the exceeding standard probability of contamination and human health risk due to the contamination were integrated. The contamination risk was defined as a combination of "vulnerability" and "hazard". To calculate the value of "vulnerability", pollutant concentration was simulated by MODFLOW with random input variables and a new modified health risk assessment(MRA) model was established to analyze the level of "hazard". The limit concentration based on environmental-guideline and health risk due to manganese were systematically examined to obtain the general risk levels through a fuzzy rule base. The "vulnerability" and "hazard" were divided into five categories of "high", "medium-high", "medium", "low-medium" and "low", respectively. Then, "vulnerability" and "hazard" were firstly combined by integrated evaluation. Compared with the other two scenarios under deterministic methods, the risk obtained in the proposed system is higher. This research illustrated that ignoring of uncertainties in evaluation process might underestimate the risk level. 展开更多
关键词 integrated evaluation RandOMNESS fuzziness modified health risk assessment uncertainty MANGANESE
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IoT Smart Devices Risk Assessment Model Using Fuzzy Logic and PSO
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作者 Ashraf S.Mashaleh Noor Farizah Binti Ibrahim +2 位作者 Mohammad Alauthman Mohammad Almseidin Amjad Gawanmeh 《Computers, Materials & Continua》 SCIE EI 2024年第2期2245-2267,共23页
Increasing Internet of Things(IoT)device connectivity makes botnet attacks more dangerous,carrying catastrophic hazards.As IoT botnets evolve,their dynamic and multifaceted nature hampers conventional detection method... Increasing Internet of Things(IoT)device connectivity makes botnet attacks more dangerous,carrying catastrophic hazards.As IoT botnets evolve,their dynamic and multifaceted nature hampers conventional detection methods.This paper proposes a risk assessment framework based on fuzzy logic and Particle Swarm Optimization(PSO)to address the risks associated with IoT botnets.Fuzzy logic addresses IoT threat uncertainties and ambiguities methodically.Fuzzy component settings are optimized using PSO to improve accuracy.The methodology allows for more complex thinking by transitioning from binary to continuous assessment.Instead of expert inputs,PSO data-driven tunes rules and membership functions.This study presents a complete IoT botnet risk assessment system.The methodology helps security teams allocate resources by categorizing threats as high,medium,or low severity.This study shows how CICIoT2023 can assess cyber risks.Our research has implications beyond detection,as it provides a proactive approach to risk management and promotes the development of more secure IoT environments. 展开更多
关键词 IoT botnet detection risk assessment fuzzy logic particle swarm optimization(PSO) CYBERSECURITY interconnected devices
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Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,China
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作者 Jian-zhou Yang Yan-gang Fu +6 位作者 Qiu-li Gong Sheng-ming Ma Jing-jing Gong Jian-weng Gao Zhen-liang Wang Yong-wen Cai Shi-xin Tang 《China Geology》 CAS CSCD 2024年第3期469-479,共11页
To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and correspo... To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use patterns.Inductively coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of PTEs.Geo-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health impacts.Results showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation effect.The concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and Hg.The I_(geo)revealed that the major accumulated element in soils was As followed by Mo.Source apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the topsoil.Noncarcinogenic risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden plot.However,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study area.The TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low level.Therefore the PTEs in the agricultural soil of the study area show little influence on the health status of the local population. 展开更多
关键词 Potentially toxic trace elements(PTEs) SOILS Land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) Total carcinogenic risk index(TR) Source apportionment Health risk Agricutural geological survey engineering
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Distribution, Enrichment and Ecological Risk Assessment of Six Elements in Bed Sediments of a Tropical River, Chottanagpur Plateau: A Spatial and Temporal Appraisal 被引量:2
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作者 Kumar Manoj Pratap Kumar Padhy 《Journal of Environmental Protection》 2014年第14期1419-1434,共16页
Distribution and enrichment of six elements (iron, zinc, copper, lead, cadmium and manganese) in surface bed sediments, collected from seventeen selected locations during pre-monsoon and postmonsoon periods, of the tr... Distribution and enrichment of six elements (iron, zinc, copper, lead, cadmium and manganese) in surface bed sediments, collected from seventeen selected locations during pre-monsoon and postmonsoon periods, of the tropical Chottanagpur plateau river Subarnarekha along with the ecological risks involved were investigated. Owing to the rich occurrence of mineral resources, the Subarnarekha river basin has a large scale presence of industrial and mining units especially in the Indian State of Jharkhand. An assessment, which involved examining distribution pattern of elements, comparative studies with sediment quality guidelines (SQGs) and geochemical background values and a sequential and integrated index analyses approach (containing contamination factor (CF), pollution load index (PLI), contamination degree (CD), enrichment factor (EF), geo-accumulation index (Igeo) and potential ecological risk index (PERI)), was followed to estimate enrichment and risks of elements in the bed sediments. Sediments collected from areas having abundance of population, industrial conglomerates and mining units recorded elevated element concentrations, which exceeded SQGs, and significantly higher values of CF, CD, PLI, EF, Igeo and PERI. Cadmium demonstrated surprising regularity in its enrichment;contributed most to the ecological risks;and high toxicity risks due to cadmium exceeded 64% of the sites. Moreover, chronic exposures of other elements would also lead to similar ecological risks. In addition to revealing potential ecological risks due to cadmium and other elements our investigation markedly highlighted anthropogenic control over sediment quality deterioration and some immediate sediment quality management strategies are needed to remediate and control river bed contamination. 展开更多
关键词 ANTHROPOGENIC Impacts Ecological risk INDEX Geo-Accumulation INDEX Trace elements Pollution Load INDEX Sediment Contamination
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New Approaches to the Prognosis and Diagnosis of Breast Cancer Using Fuzzy Expert Systems
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作者 Elias Ayinbila Apasiya Abdul-Mumin Salifu Peter Awon-Natemi Agbedemnab 《Journal of Computer and Communications》 2024年第5期151-169,共19页
Breast cancer remains a significant global health challenge, necessitating effective early detection and prognosis to enhance patient outcomes. Current diagnostic methods, including mammography and MRI, suffer from li... Breast cancer remains a significant global health challenge, necessitating effective early detection and prognosis to enhance patient outcomes. Current diagnostic methods, including mammography and MRI, suffer from limitations such as uncertainty and imprecise data, leading to late-stage diagnoses. To address this, various expert systems have been developed, but many rely on type-1 fuzzy logic and lack mobile-based applications for data collection and feedback to healthcare practitioners. This research investigates the development of an Enhanced Mobile-based Fuzzy Expert system (EMFES) for breast cancer pre-growth prognosis. The study explores the use of type-2 fuzzy logic to enhance accuracy and model uncertainty effectively. Additionally, it evaluates the advantages of employing the python programming language over java for implementation and considers specific risk factors for data collection. The research aims to dynamically generate fuzzy rules, adapting to evolving breast cancer research and patient data. Key research questions focus on the comparative effectiveness of type-2 fuzzy logic, the handling of uncertainty and imprecise data, the integration of mobile-based features, the choice of programming language, and the creation of dynamic fuzzy rules. Furthermore, the study examines the differences between the Mamdani Inference System and the Sugeno Fuzzy Inference method and explores challenges and opportunities in deploying the EMFES on mobile devices. The research identifies a critical gap in existing breast cancer diagnostic systems, emphasizing the need for a comprehensive, mobile-enabled, and adaptable solution by developing an EMFES that leverages Type-2 fuzzy logic, the Sugeno Inference Algorithm, Python Programming, and dynamic fuzzy rule generation. This study seeks to enhance early breast cancer detection and ultimately reduce breast cancer-related mortality. 展开更多
关键词 EMFES Breast Cancer Type-2 Fl Soft Computing Membership Functions Fuzzy Set Fuzzy Rules risk Factors.
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Migration of Heavy Metal Elements in Reclaimed Irrigation Water-Soil-Plant System and Potential Risk to Human Health 被引量:1
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作者 Zixi LIU Juncang TIAN +3 位作者 Wangcheng LI Lian TANG Jie WANG Haiyan GAO 《Asian Agricultural Research》 2021年第10期41-47,53,共8页
[Objectives]To study the impact of heavy metal pollution of soil and plants during the process of reclaimed water for irrigation of green land in arid areas and the potential health risks to humans during use.[Methods... [Objectives]To study the impact of heavy metal pollution of soil and plants during the process of reclaimed water for irrigation of green land in arid areas and the potential health risks to humans during use.[Methods]Taking Zhongwei City in Ningxia,a typical arid area,as the research area,the irrigation water,soil and green grass in the reclaimed water irrigation region and the original green water irrigation region were sampled,the heavy elements Hg,As,Zn,Pb,Cd,Cr were detected,and the Nemerow method,biological absorption coefficient,and health risk assessment were employed to evaluate the degree of soil pollution,plant absorption capacity,and human health risks.[Results]Compared with the original green water,the Hg,Cd,and Cr pollution of the reclaimed water irrigated green land was higher,the As,Zn,Pb pollution was lower,and the content of Hg and Cd was higher than the environmental background values of soil in Ningxia;the Cr content exceeded the risk intervention values of the first type of land in the Soil Environmental Quality—Risk Control Standard for Soil Contamination of Development Land(GB 36600-2018).Compared with the original green water irrigation region,it is found that the reclaimed water irrigation reduced the heavy metal pollution of the soil to a certain extent.The heavy metal content of tall fescue grass(Festuca arundinacea)in the reclaimed water irrigation region was Zn,Cr,Pb,As,Cd,and Hg from high to low;the order of the biological absorption coefficient was Cd>As>Zn>Pb>Hg>Cr;irrigation water exerted a certain effect on the content of heavy metals in plants and the biological absorption coefficient through the soil.Using the health risk assessment method recommended by Environmental Protection Agency of the United States of America(USEPA),it was found that the reclaimed water has the highest risk through the inhalation route,and the occupational population has a higher risk of skin contact with soil and plants.[Conclusions]This study is intended to provide data support and theoretical basis for the environmental safety risk research of the application of reclaimed water in arid areas to urban greening. 展开更多
关键词 Reclaimed water irrigation Water-soil-plant system Migration of heavy metal elements Health risk assessment
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Multi-hierarchical fuzzy judgment and nested dominance relation of rough set theory-based environmental risk evaluation for tailings reservoirs
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作者 田森 陈建宏 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4797-4806,共10页
Environmental risk assessment of tailings reservoir assessment system is complex and has many index factors.In order to accurately judge surrounding environmental risks of tailings reservoirs and determinate the corre... Environmental risk assessment of tailings reservoir assessment system is complex and has many index factors.In order to accurately judge surrounding environmental risks of tailings reservoirs and determinate the corresponding prevention and control work,multi-hierarchical fuzzy judgment and nested dominance relation of rough set theory are implemented to evaluate them and find out the rules of this evaluation system with 14 representative cases.The methods of multi-hierarchical fuzzy evaluation can overall consider each influence factor of risk assessment system and their mutual impact,and the index weight based on the analytic hierarchy process is relatively reasonable.Rough set theory based on dominance relation reduces each index attribute from the top down,largely simplifies the complexity of the original evaluation system,and considers the preferential information in each index.Furthermore,grey correlation theory is applied to analysis of importance of each reducted condition attribute.The results demonstrate the feasibility of the proposed safety evaluation system and the application potential. 展开更多
关键词 environmental risk tailings reservoir fuzzy evaluation dominance relation rough set grey correlation theory
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M/OD Risk Assessment System and Its Applications
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作者 王海福 余庆波 +1 位作者 刘有英 王辉 《Journal of Beijing Institute of Technology》 EI CAS 2009年第1期6-10,共5页
A risk assessment system named meteoroid & orbital debris risk assessment system (MODRAS) developed for assessing risks of the spacecraft under the meteoroid and debris environment (M/OD EM) is presented. The com... A risk assessment system named meteoroid & orbital debris risk assessment system (MODRAS) developed for assessing risks of the spacecraft under the meteoroid and debris environment (M/OD EM) is presented. The computing resolution of MODRAS has been verified by both the three generic spacecraft geometries of inter agency debris committee (IADC) and similar foreign software such as BUMPER, ESABASE, and MDPANTO. The results show that the system is fit well with the computing results of the foreign software. Typical applications of the system are also presented, including a manned spacecraft and a space shuttle. 展开更多
关键词 orbital debris impact risk SPACECRAFT finite element model
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Fuzzy Modelling for Predicting the Risk of Recurrence and Progression of Superficial Bladder Tumors
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作者 Laércio L. Vendite Kenia D. Savergnini +1 位作者 Ubirajara Ferreira Wagner E. Matheus 《Applied Mathematics》 2018年第10期1091-1103,共13页
Nowadays, bladder cancer is the fourth most common cancer in adults and the second most frequent urogenital tumor. Predicting recurrence and progression of superficial bladder tumors, with available clinical informati... Nowadays, bladder cancer is the fourth most common cancer in adults and the second most frequent urogenital tumor. Predicting recurrence and progression of superficial bladder tumors, with available clinical information to decide the therapy to be used is a difficult task. In this work, two mathematical models were developed to help specialists on the decision process. The mathematical tool used to formulate the model was the fuzzy sets theory, due to its capacity in dealing with uncertainties inherent in medical concepts. In the first model, Stage, Grade and Size of the tumor were also considered input variables and Risk of Recurrence of a superficial bladder tumor as output variable of the first Fuzzy Rule-Based Systems (FRBS). In the second model, in addition to the Stage, Grade and Size of the tumor, it was also considered as input variable of a second FRBS Carcinoma in situ and, the Risk of Progression of superficial tumors as an output variable. For each model, simulations were made with data originated from of patients of the Clinics Hospital/ UNICAMP and A. C. Camargo Hospital of S&atilde;o Paulo, with the aim to verify the reliability of results generated by the two systems. From a database and the possibility found by FRBS, after the possibility-probability transformation, we can generate the real probability of each fuzzy output set. 展开更多
关键词 BLADDER CANCER FUZZY Modelling RECURRENCE risk PROGRESSION risk
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Algorithm Study and Software Design of District Grid On-Line Risk Assessment Based on Fuzzy Theory
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作者 Jing Li Yadi Luo +1 位作者 Lijie Chen Donghong Zhao 《Energy and Power Engineering》 2013年第4期722-727,共6页
In the background of the design and construction of Smart Grid Operation Supporting System for District Power Networks, this paper established the weighted fault probability model of the overhead line which is based o... In the background of the design and construction of Smart Grid Operation Supporting System for District Power Networks, this paper established the weighted fault probability model of the overhead line which is based on equipment operating status, utility theory and fuzzy theory. In this model, the proper membership function is adopted to describe the influence of lightning, wind speed, line ice and temperature, and the outage rate of overhead line, derived from historical statistics, is amended. Based on this model, the power supply risk analysis software is developed to calculate the online risk indicators of district grid, and provide real-time decision support information based on risk theory for scheduling operations personnel. 展开更多
关键词 Power System FAULT PROBABILITY Mode the OVERHEAD LINE risk Assessment FUZZY theory
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MathematicalsimulationofmoderateandstrongearthquakesequenceinZhujiangDeltaanditssurroundingareasinth
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作者 孙荀英 黄新辉 原章 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第1期129-138,共10页
With the orthogonal design and the finite element methods, the outside stresses acting on the boundary and the inside tectonic stress field before the 1911 Honghai Bay earthquake are obtained. Under these stress field... With the orthogonal design and the finite element methods, the outside stresses acting on the boundary and the inside tectonic stress field before the 1911 Honghai Bay earthquake are obtained. Under these stress fields, the dislocation patterns of the faults are consistent with the observed ones. Using the softening unstabilization model for elastoplastic media to simulate the process of the earthquake occurrence, 5 moderate and strong earthquakes in these areas in this century are simulated. The results show that the moderate or strong earthquake happened only at the sections of the faults whose fault safety degree is zero. According to the present distribution of the fault safety degree, the authors predict the seismic risk zones there. 展开更多
关键词 finite element modelling seismic simulation seismic risk region orthogonal design method fault safety degree.
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