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An Interval-parameter Fuzzy Robust Nonlinear Programming Model for Water Quality Management
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作者 Min Liu Guoxin Nie +2 位作者 Ming Hu Renfei Liao Yangshuo Shen 《Journal of Water Resource and Protection》 2013年第1期12-16,共5页
Planning for water quality management is important for facilitating sustainable socio-economic development;however, the planning is also complicated by a variety of uncertainties and nonlinearities. In this study, an ... Planning for water quality management is important for facilitating sustainable socio-economic development;however, the planning is also complicated by a variety of uncertainties and nonlinearities. In this study, an interval-parameter fuzzy robust nonlinear programming (IFRNP) model was developed for water quality management to deal with such difficulties. The developed model incorporated interval nonlinear programming (INP) and fuzzy robust programming (FRP) methods within a general optimization framework. The developed IFRNP model not only could explicitly deal with uncertainties represented as discrete interval numbers and fuzzy membership functions, but also was able to deal with nonlinearities in the objective function. 展开更多
关键词 Water Quality Management INTERVAL PROGRAMMING FUZZY ROBUST PROGRAMMING Nonlinear PROGRAMMING UNCERTAINTY
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比较三种稳定剂对FeS纳米颗粒的稳定效果及对水土中镉的固定与去除性能的影响
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作者 田舒婷 赵东叶 +2 位作者 霍丽娟 马骏 杨睿 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第4期1064-1075,共12页
本研究评估了三种多糖稳定剂(羧甲基纤维素钠(CMC)、羧甲基淀粉钠(CMS)和一种水溶性淀粉)用于稳定FeS纳米颗粒的有效性,并测试了相应稳定化纳米颗粒在水和土壤中固定Cd^(2+)的性能。使用0.010 wt%CMC、0.025 wt%CMS或0.065 wt%淀粉可获... 本研究评估了三种多糖稳定剂(羧甲基纤维素钠(CMC)、羧甲基淀粉钠(CMS)和一种水溶性淀粉)用于稳定FeS纳米颗粒的有效性,并测试了相应稳定化纳米颗粒在水和土壤中固定Cd^(2+)的性能。使用0.010 wt%CMC、0.025 wt%CMS或0.065 wt%淀粉可获得完全稳定的FeS纳米颗粒(100 mg/L FeS)。CMC-FeS表现出较高的zeta负电位,淀粉-FeS保持中性,而CMS-FeS则表现出中等负电位。CMCFeS对Cd^(2+)的吸附速率最快,吸附容量也最高。当用100 mg/L CMC-FeS或CMS-FeS处理一种含Cd土壤(58.3 mg/kg Cd)后,Cd的TCLP浸出率分别降低了88.4%和68.0%。CMC-FeS和CMS-FeS均可在模型土壤中运移,显示出其在土壤中原位固定Cd^(2+)方面的潜力。土壤穿透曲线实验表明,CMC-FeS在4.5个孔体积,CMS-FeS在约25个孔体积处几乎完全穿透。柱实验结果表明,当用55个孔体积的CMC-FeS或CMS-FeS悬浮液(100 mg/L)处理该含Cd土壤后,Cd的水浸出率分别降低了98.2%和98.0%。根据目标污染物、材料在土壤中的传输特性和材料成本,可找到这三种稳定剂在土壤修复中的最佳应用。 展开更多
关键词 硫化铁纳米颗粒 稳定剂 重金属 污染物固定 土壤修复 地下水污染
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Beyond p-y method:A review of artificial intelligence approaches for predicting lateral capacity of drilled shafts in clayey soils
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作者 M.E.Al-Atroush A.E.Aboelela Ezz El-Din Hemdan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3812-3840,共29页
In 2023,pivotal advancements in artificial intelligence(AI)have significantly experienced.With that in mind,traditional methodologies,notably the p-y approach,have struggled to accurately model the complex,nonlinear s... In 2023,pivotal advancements in artificial intelligence(AI)have significantly experienced.With that in mind,traditional methodologies,notably the p-y approach,have struggled to accurately model the complex,nonlinear soil-structure interactions of laterally loaded large-diameter drilled shafts.This study undertakes a rigorous evaluation of machine learning(ML)and deep learning(DL)techniques,offering a comprehensive review of their application in addressing this geotechnical challenge.A thorough review and comparative analysis have been carried out to investigate various AI models such as artificial neural networks(ANNs),relevance vector machines(RVMs),and least squares support vector machines(LSSVMs).It was found that despite ML approaches outperforming classic methods in predicting the lateral behavior of piles,their‘black box'nature and reliance only on a data-driven approach made their results showcase statistical robustness rather than clear geotechnical insights,a fact underscored by the mathematical equations derived from these studies.Furthermore,the research identified a gap in the availability of drilled shaft datasets,limiting the extendibility of current findings to large-diameter piles.An extensive dataset,compiled from a series of lateral loading tests on free-head drilled shaft with varying properties and geometries,was introduced to bridge this gap.The paper concluded with a direction for future research,proposes the integration of physics-informed neural networks(PINNs),combining data-driven models with fundamental geotechnical principles to improve both the interpretability and predictive accuracy of AI applications in geotechnical engineering,marking a novel contribution to the field. 展开更多
关键词 Laterally loaded drilled shaft load transfer and failure mechanisms Physics-informed neural networks(PINNs) P-y curves Artificial intelligence(AI) DATASET
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基于磁性纳米粒子固定技术的漆酶传感器用于垃圾堆肥中邻苯二酚的检测 被引量:17
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作者 章毅 曾光明 +2 位作者 汤琳 郁红艳 李建兵 《环境科学》 EI CAS CSCD 北大核心 2007年第10期2320-2325,共6页
以邻苯二酚为检测目标,研究了一种基于核/壳磁性纳米粒子固定漆酶的邻苯二酚生物传感器制备方法及其在城市生活垃圾堆肥中的应用.制备Fe3O4磁性纳米颗粒,使用正硅酸乙酯(TEOS)和氨丙基三甲氧基硅烷(APTMS)将其功能化并利用戊二醛将... 以邻苯二酚为检测目标,研究了一种基于核/壳磁性纳米粒子固定漆酶的邻苯二酚生物传感器制备方法及其在城市生活垃圾堆肥中的应用.制备Fe3O4磁性纳米颗粒,使用正硅酸乙酯(TEOS)和氨丙基三甲氧基硅烷(APTMS)将其功能化并利用戊二醛将漆酶共价固定,借助磁场吸附在磁性碳糊电极上,检测邻苯二酚.固定在电极表面的漆酶保持了很好的活性.该生物传感器的检测线性范围为7.5×107~2.75×10-4mol/L,检测下限达到7.5×10^-7 mol/L,达到稳态电流95%所需时间大概为70 s.将该传感器检测堆肥浸出液中酚的含量的结果与高效液相色谱法对比,两者非常接近. 展开更多
关键词 Fe3O4磁性纳米颗粒 漆酶 邻苯二酚 堆肥
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基于不确定条件下的北京电源规划优化模型 被引量:17
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作者 梁宇希 黄国和 +2 位作者 林千果 张晓萱 牛彦涛 《电力系统保护与控制》 EI CSCD 北大核心 2010年第15期53-59,共7页
电源规划是电力系统中非常重要的规划,直接影响系统今后运行的可靠性、经济性、电能质量、网络结构及其将来的发展。以北京地区为例,建立了一个不确定性电源规划优化模型。本模型引入区间混合整数线性规划方法,可以有效地解决电源规划... 电源规划是电力系统中非常重要的规划,直接影响系统今后运行的可靠性、经济性、电能质量、网络结构及其将来的发展。以北京地区为例,建立了一个不确定性电源规划优化模型。本模型引入区间混合整数线性规划方法,可以有效地解决电源规划模型中存在的不确定性问题和发电机组的装机扩建问题。结果表明:北京市将初步建立起以煤、气发电为主,新能源和可再生能源发电等为补充的多元化电源结构,为首都经济社会发展和人民生活水平的提高提供安全可靠、稳定充足的电力供应。 展开更多
关键词 不确定性 电源规划 区间规划 装机扩建 优化
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脂质体免疫传感器的研究进展 被引量:7
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作者 李庭 曾光明 +2 位作者 汤琳 高慧 李建兵 《分析化学》 SCIE EI CAS CSCD 北大核心 2008年第1期122-126,共5页
综述了脂质体免疫传感器的工作原理和制备方法,探讨了脂质体免疫传感器在痕量物质分析检测中的应用和发展方向。
关键词 脂质体 免疫传感器 痕量有害物质 环境监测 评述
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重庆市环境友好型土地利用评价研究 被引量:19
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作者 杜加强 王金生 +2 位作者 张桐 Yumin Chen 滕彦国 《中国土地科学》 CSSCI 北大核心 2008年第12期17-24,共8页
研究目的:确定环境友好型土地利用的概念、评价指标体系和适宜的评价方法。研究方法:文献资料法、理论分析法、多指标综合评价法、组合评价法、统计检验法。研究结果:构建了一套包括40个指标、具有层次结构的环境友好型土地利用评价指... 研究目的:确定环境友好型土地利用的概念、评价指标体系和适宜的评价方法。研究方法:文献资料法、理论分析法、多指标综合评价法、组合评价法、统计检验法。研究结果:构建了一套包括40个指标、具有层次结构的环境友好型土地利用评价指标体系;确定变异系数法确定权重的TOPsIs评价方法为最优评价方法;重庆市计算结果表明,除2005年之外,土地利用的环境友好水平总体上呈逐年升高的趋势。研究结论:评价指标体系基本可以反映环境友好型土地利用的状态和水平;建立的指标体系和评价思路比较适合于环境友好型土地利用模式的评价;重庆市今后应从优化土地利用结构和提高资源利用效益两方面提高土地利用的环境友好水平。 展开更多
关键词 土地生态 环境友好型土地利用 综合评价 组合评价 重庆市
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膜过滤单元对微生物的截留性能及完整性检测概述 被引量:2
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作者 王小(亻毛) 葛明明 +2 位作者 刘文君 杨宏伟 解跃峰 《给水排水》 CSCD 北大核心 2014年第3期27-32,共6页
膜过滤在饮用水处理领域具有广阔的应用前景。膜过滤单元对微生物等颗粒物质的持续有效截留是膜过滤工艺成功应用的关键。膜组件在用于实际饮用水生产之前,需要通过微生物负荷试验确定其对微生物的截留性能。膜过滤单元在运行过程中,需... 膜过滤在饮用水处理领域具有广阔的应用前景。膜过滤单元对微生物等颗粒物质的持续有效截留是膜过滤工艺成功应用的关键。膜组件在用于实际饮用水生产之前,需要通过微生物负荷试验确定其对微生物的截留性能。膜过滤单元在运行过程中,需要进行例行的膜完整性检测以保证其对微生物持续高效的截留效果。主要参考美国环保局的《膜过滤指南》,对微生物负荷试验、膜过滤单元的直接和间接完整性检测进行总结性介绍,重点阐明上述试验和检测之间的作用、基本原理、主要方法和相互关系。以促进制水企业和相关管理部门对膜过滤工艺的了解,并帮助国内膜生产企业完善其现有产品和控制系统。 展开更多
关键词 膜过滤工艺 微生物 负荷试验 完整性检测 截留性能 饮用水处理
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湿式氧化用于染料废水脱色:过去20年回顾(英文) 被引量:12
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作者 Jie Fu George Z.Kyzas 《催化学报》 SCIE EI CAS CSCD 北大核心 2014年第1期1-7,共7页
Wet air oxidation(WAO), a liquid phase reaction between organic materials in water and oxygen, is one of the most economical and technologically viable advanced oxidation processes for wastewater treatment, particular... Wet air oxidation(WAO), a liquid phase reaction between organic materials in water and oxygen, is one of the most economical and technologically viable advanced oxidation processes for wastewater treatment, particularly toxic and high organic content wastewater. WAO is the liquid phase oxidation of organics or oxidizable inorganic components at elevated temperatures(125–320 °C) and pressures(0.5–20 MPa) using gaseous oxygen(or air) as oxidant. In the past two decades, the WAO process was widely studied and applied in the treatment of dye wastewater. Compared to conventional WAO, catalytic WAO processes have higher efficiency and use moderate reaction conditions. The catalysts included homogenous and heterogeneous types. The key points that need to be solved are recycling of homogenous catalysts and better stability of heterogeneous catalysts. In the present review, the technological processes are first introduced, then some research history and hotspots of WAO research are presented, and finally, its application in the treatment of dye wastewater in the past two decades is summarized to reveal the impressive changes in modes, trends, and conditions used. The application includes model pollutant studies and wastewater tests. 展开更多
关键词 染料废水处理 湿式空气氧化 非均相催化剂 有机物含量 脱色 湿式氧化工艺 液相反应 催化剂包
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Scavenging of Cd through Fe/Mn oxides within natural surface coatings 被引量:4
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作者 LI Yu HUANG Guo-he +1 位作者 ZHANG Bai-yu GUO Shu-hai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1199-1203,共5页
The dynamics of Cd scavenging from solutions by Fe/Mn oxides in natural surface coatings (NSCs) was investigated under laboratory conditions. Selective extraction methods were employed to estimate the contributions ... The dynamics of Cd scavenging from solutions by Fe/Mn oxides in natural surface coatings (NSCs) was investigated under laboratory conditions. Selective extraction methods were employed to estimate the contributions of Fe/Mn oxides, where hydroxylamine hydrochloride (0.01 mol/L NH2OH-HCl + 0.01 mol/L HNO3), sodium dithionite (0.4 mol/L Na2S2O4) and nitric acid (10% HNO3) were used as extraction reagents. The Cd scavenging was accomplished with developing periods of the NSCs (totally 21 data sets). The resulting process dynamics fitted well to the Elovich equation, demonstrating that the amount of Cd scavenged was proportional to the increments of Fe/Mn oxides that were accumulated in the NSCs. The amount of Cd bound to Fe oxides (MCdFe) and Mn oxides (MCdMn) could be quantified by solving two equations based on the properties of two extraction reagents. The amount of Cd scavenged by Fe/Mn oxides could also be estimated using MCdFe and MCdMn divided by the total amounts of Fe and Mn oxides in the NSCs, respectively. The results indicated that the Cd scavenging by Fe/Mn oxides was dominated by Fe oxides, with less roles attributed to Mn oxides. The estimated levels of Cd scavenging through Fe and Mn oxides agreed well with those predicted through additive-adsorption and linear-regression models. 展开更多
关键词 CADMIUM SCAVENGING natural surface coatings selective extraction iron oxides manganese oxides
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Characterization and Modification of a Clay Mineral Used in Adsorption Tests 被引量:1
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作者 Natália Costa Dias Patrícia Arns Steiner Maria Cristina Borba Braga 《Journal of Minerals and Materials Characterization and Engineering》 2015年第4期277-288,共12页
Clay minerals are widespread in natural systems and have been widely used for the removal of pollutants. In this study, natural expanded vermiculite was used in adsorption tests to remove ammonium nitrogen from landfi... Clay minerals are widespread in natural systems and have been widely used for the removal of pollutants. In this study, natural expanded vermiculite was used in adsorption tests to remove ammonium nitrogen from landfill leachate. The modification of vermiculite was carried out using NaOH and HCl, and for both modifications the best concentration was 0.1 mol/L. The results produced by XRD (X-ray diffraction) showed that Al replaced K after modification of the vermiculite using HCl and that Mg and Na replaced K after modification using NaOH. It was observed that the adsorption capacity increased as the percentage in mass of K diminished. The Langmuir is the isotherm that presents the best fit of the data, and the values of RL (the Langmuir coefficient) suggest that the adsorption is linear. The thermodynamic parameters indicate that the process is spontaneous and endothermic, that there is a high affinity between the adsorbate and the adsorbent, and that physical adsorption is prevalent. 展开更多
关键词 ADSORPTION Isotherms ADSORPTION THERMODYNAMICS Clay MINERALS Expanded VERMICULITE LANDFILL LEACHATE VERMICULITE
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Formation of Struvite Crystals in a Simulated Food Waste Aerobic Composting Process 被引量:1
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作者 DU Xian-yuan LIU Jian-lin +1 位作者 HUANG Guo-he LI YU 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第2期210-216,共7页
Bench-scale treatments with three mixtures of Mg and P salts, including K3PO4+MgSO4, K2HPO4+MgSO4, and KH2PO4+MgSO4 as additives in a simulated food waste aerobic composting process, were conducted to test the magn... Bench-scale treatments with three mixtures of Mg and P salts, including K3PO4+MgSO4, K2HPO4+MgSO4, and KH2PO4+MgSO4 as additives in a simulated food waste aerobic composting process, were conducted to test the magnesium ammonium phosphate(MAP) formation, and the compost products were analyzed by X-ray diffraction(XRD), Scanning electron microscopy(SEM), and Energy dispersive X-ray spectroscopy(EDS) analyses. The comparison results between XRD, SEM, and EDS analyses of MAPs in the dried compost and synthesized MAPs confirm the formation of MAP crystals in the simulated food waste aerobic composting process. The analysis of the compost also indicates that the addition of all the three mixtures of Mg and P salts in the aerobic composting process can increase nitrogen conservation and decrease nitrogen loss because of the formation of MAPs. The mechanism of MAP formation was verified as the reaction of ammonium(NH4+) with magnesium(Mg^2+) and phosphate[HnPO4^(3-n) , n=0, 1, and 2). 展开更多
关键词 PHOSPHATE Magnesium sulphate Magnesium ammonium phosphate Food waste treatment Aerobic composting
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Chemical and Morphological Study of PM10 Analysed by SEM-EDS 被引量:2
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作者 Roberto Ramirez-Leal Maryanna Valle-Martinez Martin Cruz-Campas 《Open Journal of Air Pollution》 2014年第4期121-129,共9页
Single particle characterization can provide information on the evolution of size distribution and chemical composition of pollution aerosol. The work described the use of Scanning Electron Microscopy (SEM) combined w... Single particle characterization can provide information on the evolution of size distribution and chemical composition of pollution aerosol. The work described the use of Scanning Electron Microscopy (SEM) combined with X-ray Dispersive Energy Spectrometry (EDS) to characterize inorganic atmospheric particles samples collected on PM10 filters from January 2013 to October 2013 from three zones within the city of Hermosillo, Sonora. Specimens were initially processed by separating the collected particles from the filters by means of submersing a 2 cm2 section of each filter into isopropilic alcohol within a test tube for 5 minutes. Then, an aliquot of the suspension was placed over a sample holder and into the SEM. The different elements found amongst individual particles were Al, Ba, Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Pb, S, Si, Ti and U. The predominant elements are Al (17.10 At%), Si (10.17 At%), Ba (5.90 At%), Fe (5.45 At%) and U (2.32 At%). The particles were classified into groups based on morphology and elemental composition: particles of aluminosilicate, salts of sodium chloride, sulfates, metal particles, barium and uranium. These particles morphology and chemical composition, illustrate an abundance of natural elements within the zone. However, some of the elements presented are directly related with human activities, and are of much interest from the public health and environmental perspectives. 展开更多
关键词 PM10 Air Quality SEM EDS MORPHOLOGY
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How Do People Understand Urban Air Pollution? Exploring Citizens’ Perception on Air Quality, Its Causes and Impacts in Colombian Cities 被引量:1
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作者 Omar Ramírez Ivan Mura Juan Felipe Franco 《Open Journal of Air Pollution》 2017年第1期1-17,共17页
Similarly to other Latin American countries, urban air quality is a major concern in Colombia. The purpose of the present study was to explore citizens’ perception on local air pollution, its causes and impacts. A qu... Similarly to other Latin American countries, urban air quality is a major concern in Colombia. The purpose of the present study was to explore citizens’ perception on local air pollution, its causes and impacts. A questionnaire was individually applied to a sample of 994 participants. Relationships between demographic features and the perception on air quality were analyzed using a logistic regression, its odds ratio (OR), and a Chi-square test. Eighty percent of the respondents perceive their local air quality as either bad or fair, 65% recognize particulate matter as the main local air pollutant, and 90% recognize negative impacts on people’s health as the main consequence of air pollution. In contrast to other studies where age and economic status are variables highly related with public perception on the level of atmospheric pollution, in this study only the size of the cities has a statistically significant relationship with the perception on local air quality regarding the level of pollution(OR ≥ 1, confidence intervals > 1 and p-values < 0.05). While area sources such as mining and infrastructure construction are identified as the main sources of pollutant emissions in small towns (less than 50,000 inhabitants), in big cities, road traffic is identified as the main source contributor to atmospheric pollution. Opposite to data from official reports, and regardless of the size of the city, households are perceived as the place with greatest contribution to personal air pollution exposure. Results show that citizens are aware of the state of air quality and its health impact is a major concern. Such findings suggest people’s opinions can be used as provisional indicators in cities without data, as well as to monitor the results of local air quality management. As a complementary process, or at the same level of importance given to technical-based policy, citizen participation can contribute to a collective construction of urban air pollution control strategies. 展开更多
关键词 Public PERCEPTION CITIZEN PARTICIPATION AIR Quality AIR Pollution Colombia
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Mitigation of municipal solid waste leachate contamination at Payatas, Metro Manila, Philippines: A technical proposal
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作者 Marvin Joseph Montefrio Kai Scene Ng +4 位作者 Lee Yih Koh Erwin Torio Mark Hansley Chua Louernie de Sales-Papa Jeffrey Philip Obbard 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期122-122,共1页
关键词 固体废物 沥出物 湿地 环境污染 环境控制
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Influence of Headland Breakwaters on Morphological Processes at Longfengtou Beach in Haitan Bay,Facing the Taiwan Strait
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作者 KUANG Cuiping MA Yue +4 位作者 WANG Binyu SUI Jueyi GU Jie LIU Jianhui LEI Gang 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第6期1290-1300,共11页
Breakwaters can be used as artificial headlands in beach nourishment to mitigate coastal erosion. Longfengtou Beach, located on the southwest coast of Haitan Bay facing the Taiwan Strait on the northeast, suffers seve... Breakwaters can be used as artificial headlands in beach nourishment to mitigate coastal erosion. Longfengtou Beach, located on the southwest coast of Haitan Bay facing the Taiwan Strait on the northeast, suffers severe erosion, where the monsoon causes significant season hydrodynamic variations. Headland breakwaters are intended to be employed to mitigate coastal erosion. A 2D sediment transport model is established using MIKE21 based on current-wave coupling and calibrated by measured data. Summer and winter wave conditions are chosen as characteristic weak and strong waves respectively. The numerical results of suspended sediment concentration and seasonal morphological evolution are compared under the conditions with and without the headland breakwaters. Sediment transport in summer can be regarded as mainly determined by current field, while in winter wave effect is strong enough to change current field. The northern breakwater, nearly perpendicular to the ebb current direction, obstructs the currents and decreases velocity of the ebb currents, and confines the water carrying sediments within the protection area during the flood period. The southern breakwater also breaks the waves in advance and significantly reduces the hydrodynamic effects during the flood period and maintains high suspended sediment concentration in the protection area. In general, two headland breakwaters decrease the erosion near the beach and enlarge the deposition area, which play a significant role in prevention of sediment loss in nearshore area and mitigate coastal erosion. 展开更多
关键词 HEADLAND BREAKWATER Haitan BAY sediment transport morphological evolution
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Comparison of Three Commonly Used Equations for Calculating Local Scour Depth around Bridge Pier under Ice Covered Flow Condition
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作者 Mohammad Reza Namaee Yuquan Li +1 位作者 Jueyi Sui Todd Whitcombe 《World Journal of Engineering and Technology》 2018年第2期50-62,共13页
A precise prediction of maximum scour depth around bridge foundations under ice covered condition is crucial for their safe design because underestimation may result in bridge failure and over-estimation will lead to ... A precise prediction of maximum scour depth around bridge foundations under ice covered condition is crucial for their safe design because underestimation may result in bridge failure and over-estimation will lead to unnecessary construction costs. Compared to pier scour depth predictions within an open channel, few studies have attempted to predict the extent of pier scour depth under ice-covered condition. The present work examines scour under ice by using a series of clear-water flume experiments employing two adjacent circular bridge piers in a uniform bed were exposed to open channel and both rough and smooth ice covered channels. The measured scour depths were compared to three commonly used bridge scour equations including Gao’s simplified equation, the HEC-18/Jones equation, and the Froehlich Design Equation. The present study has several advantages as it adds to the understanding of the physics of bridge pier scour under ice cover flow condition, it checks the validity and reliability of commonly used bridge pier equations, and it reveals whether they are valid for the case of scour under ice-covered flow conditions. In addition, it explains how accurately an equation developed for scour under open channel flow can predict scour around bridge piers under ice-covered flow condition. 展开更多
关键词 ICE COVER Local SCOUR Bridge PIERS Maximum SCOUR Depth
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Relationship Population Density of Aquatic Sediment Macrozoobenthos to River Water Quality Parameters: Case Study of Upstream Citarum River in Bandung Regency
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作者 Barti Setiani Muntalif Nurul Chasanah Mohammad Faiz Faza 《Journal of Environmental Science and Engineering(A)》 2016年第3期117-125,共9页
The increase in anthropogenic activities occur along the upstream of Citarum River Basin (CRB) in Bandung regency had a negative impact to the water quality caused by the presence of human activity, it will be able ... The increase in anthropogenic activities occur along the upstream of Citarum River Basin (CRB) in Bandung regency had a negative impact to the water quality caused by the presence of human activity, it will be able to be a disruption to the ecosystem aquatic. The purpose of this study was to determine the relationship of the physical and chemical parameters of water and sediment to the presence of macrozoobenthos populations. Based on the result of Pearson Correlation Analysis (PCA), the parameters of COD, TOC and silt composition were the highest correlation to the macrozoobenthos population density, the value were 0.966, 0.865 and 0.576. Although PCA analysis is used to determine the relationship between the parameters of water, sediment and sediment particle distribution, the result showed that the water parameters were the mayor component affected the density of macrozoobenthos. While based on the composition of sediment, it is found that substrate as silt, clay and gravel and phosphate parameter affected the density of macrozoobenthos. The measurement of water quality also were calculated by Biotic Monitoring Working Party-Average Score Per Taxon (BMWP-ASPT) index showed that the quality were polluted condition, although by Pollution Index (IP) method showed as a light polluted category. 展开更多
关键词 Citarum upstream correlation SEDIMENT macrozoobenthos water quality.
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Coliform Bacteria: The Effect of Sediments on Decay Rates and on Required Detention Times in Stormwater BMPs
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作者 Alison R. Kinnaman Cristiane Q. Surbeck Danielle C. Usner 《Journal of Environmental Protection》 2012年第8期787-797,共11页
Fecal indicator bacteria, such as total coliforms and E. coli, are a challenge to control in urban and rural stormwater runoff. To assess the challenges of improving bacterial water quality standards in surface waters... Fecal indicator bacteria, such as total coliforms and E. coli, are a challenge to control in urban and rural stormwater runoff. To assess the challenges of improving bacterial water quality standards in surface waters, microcosm experiments were conducted to assess how decay rates of total coliforms and E. coli are affected by sediments and associated organic matter. Samples were collected at a lake embayment to create laboratory microcosms consisting of different combinations of unsterilized and sterilized water and sediment. Calculated first-order decay rate constants ranged from 0.021 to 0.047 h-1 for total coliforms and 0.017 and 0.037 h-1 for E. coli, depending on how each microcosm was prepared. It is evident that sediment in contact with the water column decreases bacteria decay rate, showing that care should be taken when designing stormwater treatment measures. In addition, high organic carbon content in the sediment temporarily increased bacteria concentrations in the water column. The results demonstrate that stormwater treatment measures, such as extended detention basins and constructed wetlands, must hold water for several days to allow for reduction of bacterial concentrations to acceptable levels. In addition, to troubleshoot detention basins and constructed wetlands for causes of high effluent bacterial concentrations, analyses of sediment, organic carbon, and water column depth should be conducted. 展开更多
关键词 FECAL Indicator Bacteria Decay Rate Sediment NUTRIENTS Organic Carbon Best Management Practices (BMPs)
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Comparative Analysis between Community and Occupants’ Rating Systems for Sustainable Urban Communities (SUC)
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作者 Mianda Khattab Salah El Haggar Ahmed El Gendy 《Journal of Environmental Protection》 CAS 2022年第11期881-894,共14页
Overpopulation globally is an addressed issue impacting human lives, marine lives, and the surrounding ecosystem;it is adding pressure on the available resources that should be optimized to suit the needs. Yet with im... Overpopulation globally is an addressed issue impacting human lives, marine lives, and the surrounding ecosystem;it is adding pressure on the available resources that should be optimized to suit the needs. Yet with improper management of resources and monitoring of daily activities, the environment will be further negatively impacted. With overpopulation higher urbanization rates are noticed with the demand of seeking better health facilities, better education, better jobs and better well-being;this progression is driving more demand into the infrastructure sector to be able to accommodate the growth rates. Hence, the need to having sustainable communities aiming at optimizing the resources used, working towards more feasible, environmentally friendly and cost-effective communities with a better occupant’s experience is in action. Sustainable development goals (SDG) are vital goals developed by the United Nations Development Program (UNDP) in 2015 to address and guide through 17 interconnected global goals serving the previously mentioned trend. Out of the 17 goals, Sustainable Cities and Communities (goal #11) and Good Health and Well-Being (goal #3) are the focus of this paper directed towards holding a comparative analysis between the community scale commonly known and mostly used rating system Leadership of Energy and Environmental Design (LEED-Cities and Communities) (USA) versus similar rating systems like Tarsheed-Communities (Egypt) and Estidama-Pearl (UAE) rating systems meeting sustainable development goal #11. Conjointly, another complimenting comparative review of the occupant’s health and wellbeing rating systems, such as Fitwel (USA) and Well (USA) are studied under sustainable development goal #3;however, they are focused on a building scale assessment. Living Community Challenge (LCC, USA) rating system linking community rating system with health & wellbeing credits was first issued in 2006, yet is it not cost effective neither easy to apply acting as a primary step while being affordable, accessible, and easy to implement. The objective of this paper is to highlight the pros and gaps under both categories of studies of community rating system and occupants’ health & wellbeing rating systems based on scientific content and commercial acceptance and do-ability. This comparison is done via comparing credits and sections within each rating system type;this will support in addressing the focal points needed for an integrated rating system between both categories that will serve in meeting SDG Sustainable Cities and Communities (goal #11) and Good Health and Well-Being (goal #3). 展开更多
关键词 Sustainable Communities Sustainable Community Rating Systems Occupant’s Health & Well-Being Rating System SDG#3 (Good Health and Well-Being) SDG#11 (Sustainable Cities and Communities)
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