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基于模糊综合评价法的多源污泥协同建材利用综合解决方案研究

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给水排水 2024年第1期50卷 11-16页

作者：张辰谭学军金宁奔刘战广段妮娜王盼上海市政工程设计研究总院(集团)有限公司上海200092

针对城市多源污泥主体多、产量大、来源复杂、处置分散等问题,以及缺乏适用可靠的综合解决方案等难题,在对多源污泥协同建材利用影响因素进行分析的基础上,建立多源污泥协同建材利用技术路线评价两级指标体系。综合分析各评价指标之间... 详细信息

针对城市多源污泥主体多、产量大、来源复杂、处置分散等问题,以及缺乏适用可靠的综合解决方案等难题,在对多源污泥协同建材利用影响因素进行分析的基础上,建立多源污泥协同建材利用技术路线评价两级指标体系。综合分析各评价指标之间的相关性,基于专家调查法和层次分析法,构建模糊综合评价模型,并对多源污泥协同建材利用技术路线进行评价。通过实例分析,验证了该评价方法的有效性,并提出了城市多源污泥协同建材利用综合解决方案优化的建议。

关键词：模糊综合评价法层次分析法多源污泥协同建材利用综合解决方案

变温条件下解析Preisach磁滞模型误差修正和特征参数辨识方法

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电工电能新技术 2024年第6期43卷 60-69页

作者：陈彬曾庆麟王斐然万妮娜黄力唐波湖北省输电线路工程技术研究中心(三峡大学) 湖北宜昌443002 三峡大学电气与新能源学院湖北宜昌443002 国网湖北省电力有限公司宜昌供电公司湖北宜昌443002

温度升高会影响磁性材料的磁滞特性,从而改变电气设备的性能。目前解析Preisach模型无法对温度进行有效表征,导致损耗计算结果误差较大。为此,本文首先分析了基于Lorentzian函数的解析Preisach模型特征参数对磁滞回线形状参数的影响程度... 详细信息

温度升高会影响磁性材料的磁滞特性,从而改变电气设备的性能。目前解析Preisach模型无法对温度进行有效表征,导致损耗计算结果误差较大。为此,本文首先分析了基于Lorentzian函数的解析Preisach模型特征参数对磁滞回线形状参数的影响程度,如饱和磁通密度、矫顽力、剩磁等,研究了不同温度下模型参数和材料磁特性的变化。根据模型特征参数具有的磁滞回线形状相关性和温度相关性,引进温度系数来修正模型特征参数,构建变温条件下的解析Preisach模型,并给出了计及温度影响的模型参数辨识方法。最终实验测量纳米晶合金在变温条件下的极限磁滞回线,对多组实测值和修正后的解析Preisach模型计算值进行对比后,得出在饱和磁通密度、矫顽力和剩磁处修正模型结果的平均相对误差分别为0.15%、2.21%、5.76%,证明了该修正模型的准确性。

关键词：解析Preisach磁滞模型可逆磁化磁滞回线温度特性参数辨识

裂褶菌发酵西洋参工艺优化及体外抗氧化能力研究

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食品工业科技 2024年第7期45卷 142-151页

作者：王崑仑管立军高扬严松李家磊季妮娜李波周野黑龙江省农业科学院食品加工研究所黑龙江哈尔滨150086 黑龙江省食品加工重点实验室黑龙江哈尔滨150086 黑龙江省农业科学院大豆研究所黑龙江哈尔滨150086

为提高西洋参的经济价值,本研究以西洋参为原料,利用裂褶菌固态发酵西洋参,提高西洋参中活性成分的含量,并对发酵工艺进行优化。本研究以西洋参中总人参皂苷含量为指标,先从3种裂褶菌菌株中筛选出2号菌株作为固态发酵西洋参用菌。再对... 详细信息

为提高西洋参的经济价值,本研究以西洋参为原料,利用裂褶菌固态发酵西洋参,提高西洋参中活性成分的含量,并对发酵工艺进行优化。本研究以西洋参中总人参皂苷含量为指标,先从3种裂褶菌菌株中筛选出2号菌株作为固态发酵西洋参用菌。再对影响裂褶菌西洋参发酵物的总人参皂苷含量的4个因素(发酵温度、裂褶菌接种量、pH和发酵时间)进行单因素实验。在此结果基础上,利用响应面Box-Behnken试验设计进一步优化裂褶菌固态发酵西洋参工艺,确定优化后的工艺条件为:裂褶菌接种量10.90%,发酵温度31℃、发酵时间10 d,发酵pH5.9。在上述条件下,裂褶菌西洋参发酵物的总人参皂苷含量为10.28%,粗多糖含量为12.85%,总黄酮含量为0.67%,均比未发酵西洋参的高。并且大分子人参皂苷Rb1、Rg_(2)和Re含量降低,小分子人参皂苷Rg_(1)、Rc、Rb_(2)、>、Rd、Rg3、s-Rh_(2)、r-Rh_(2)和拟人参皂苷CK含量升高。其中,稀有人参皂苷Rg_(3)、s-Rh_(2)、r-Rh_(2)和拟人参皂苷CK为新出现皂苷。体外抗氧化实验表明裂褶菌西洋参发酵物的DPPH和ABTS^(+)自由基清除能力的IC_(50)值分别为31365和10910μg/mL,均强于未发酵西洋参。本研究证明了裂褶菌固态发酵西洋参提高了总人参皂苷、粗多糖、总黄酮和稀有人参皂苷的含量,增强了抗氧化能力,为西洋参的开发利用提供数据支持。

关键词：西洋参裂褶菌固态发酵响应面人参皂苷抗氧化

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一种新型重度铬污染土壤修复技术

科技创新与应用 2024年第13期14卷 30-34页

作者：蒋妮娜李东李林高然重庆远达烟气治理特许经营有限公司科技分公司重庆401122 重庆大学环境与生态学院重庆400044

我国退役铬化工企业的土壤铬污染严重,部分土壤六价铬浓度可高达10^(3)~10^(4)mg·kg^(-1),对植物生长、人类活动产生了不良影响。常用的铬污染土壤修复方法有还原修复技术、生物修复技术、酸淋洗-还原联合修复技术,用稀酸溶液加上还原... 详细信息

我国退役铬化工企业的土壤铬污染严重,部分土壤六价铬浓度可高达10^(3)~10^(4)mg·kg^(-1),对植物生长、人类活动产生了不良影响。常用的铬污染土壤修复方法有还原修复技术、生物修复技术、酸淋洗-还原联合修复技术,用稀酸溶液加上还原剂将土壤中的六价铬浸出、还原。但酸溶液对难提取六价铬的溶解效果有限,且易引起土壤侵蚀等次生环境问题。碱性条件下重度铬污染土壤淋洗和还原的修复工艺能有效解决酸淋洗存在的土壤溶蚀、钙流失、含盐量大幅增加以及其他重金属浸出浓度超标等次生环境问题,且该技术通过碱淋洗还原工艺显著提高难提取六价铬的提取和还原效率,该研究形成经济可行、易于推广的铬污染土壤修复技术路线。

关键词：污染土壤修复重度铬六价铬

Multiplex Rapid Test with Acceptable Diagnosis Performance as a Solution to Increase Diagnosis of hepatitis B and C Viruses in Pregnant Women in an Area of High Prevalence of Both hepatitis Viruses Associated with HIV

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Open Journal of Medical Microbiology 2024年第1期14卷 50-65页

作者： Catherine Boni-Cisse nina Esther Onstira Ngoyi hermione Dahlia Mossoro-Kpinde Noella Packo Rabi Senekian hermann Ndoidet Koutou Coretha Bokia-Baguida Christelle Luce Bobossi-Gadia Arthur Simplice Sombot-Ndicky Daniel Yvon Gonessa Freddy Samuel Ngbonga Konzapa Voulou Christian Diamant Mossoro-Kpinde Alassane OUATTARA National Center of Medical Oncology and Radiotherapy Abidjan Ivory Cost Department of Microbiology UFR of Medical Sciences University of Cocody Abidjan Ivory Cost Laboratory of Bacteriology-Virology of Teaching Hospital Center of Brazzaville Brazzaville Republic of Congo Faculty of health Sciences Marien NGOUABI University Brazzaville Republic of Congo Department of Labor Medicine Service of HIV and STDs Control in the Workplace Bangui Central African Republic (CAR) Faculty of health Sciences University of Bangui Bangui Central African Republic National Reference Center of Sexually Transmitted Diseases and Antiretroviral Therapy Bangui Central African Republic National Laboratory of Clinical Biology and Public health Bangui Central African Republic Medicine Department District Hospital of Alindao Alindao Ouaka Prefecture Central African Republic Doctoral School of Sciences and Technology University of Bangui Bangui Central African Republic Coordination of Specialized Study of Clinical Biology University of Bangui Bangui Central African Republic Doctors without Borders Hospital Sica BanguiCRA Laboratory of Medical Analysis of Teaching Hospital Center Mother Elisabeth DOMITIEN of Bimbo Bimbo Central African Republic

Background and Objective: HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) are very widespread in the world, however, less than 20% of the people affected are diagnosed and treated. This study aimed to determine the prevalence of HIV, HCV and HBV co-infections in pregnant women at Bangui Community University Hospital and the cost of screening. Methods: A cross-sectional study involving consenting pregnant women who came for antenatal care was performed. HIV, HCV antibodies and HBV antigens were detected using Exacto Triplex? HIV/HCV/HBsAg rapid test, cross-validated by ELISA tests. Sociodemographic and professional data, the modes of transmission and prevention of HIV and both hepatitis viruses were collected in a standard sheet and analyzed using the Epi-Info software version 7. Results: Pregnant women aged 15 to 24 were the most affected (45.3%);high school girls (46.0%), and pregnant women living in cohabitation (65.3%) were the most represented. Twenty-five (16.7%) worked in the formal sector, 12.7% were unemployed housewives and the remainder in the informal sector. The prevalence of HIV, HBV, and HCV viruses was 11.8%, 21.9% and 22.2%, respectively. The prevalence of co-infections was 8.6% for HIV-HBV, 10.2% for HIV-HCV, 14.7% for HBV-HCV and 6.5% for HIV-HBV-HCV. All positive results and 10% of negative results by the rapid test were confirmed by ELISA tests. The serology of the three viruses costs 39,000 FCFA (60 Euros) by ELISA compared to 10,000 FCFA (15.00 Euros) with Exacto Triplex? HIV/HCV/AgHBs (BioSynex, Strasbourg, France). Conclusion: The low level of education and awareness of hepatitis are barriers to development and indicate the importance of improving the literacy rate of women in the Central African Republic (CAR). Likewise, the high prevalence of the three viruses shows the need for the urgent establishment of a national program to combat viral hepatitis in the CAR.

关键词： HIV-HCV-HBV Co-Infection Multiplex Immunochromatographic Rapid Test Central Africa Serology Test Cost Diagnostic Accessibility

Item-level Forecasting for E-commerce Demand with High-dimensional Data Using a Two-stage Feature Selection Algorithm

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Journal of Systems Science and Systems Engineering 2022年第2期31卷 247-264页

作者： Hongyan Dai Qin Xiao nina Yan Xun Xu Tingting Tong Business School Central University of Finance and EconomicsBeijing 100081China Department of Management Operationsand MarketingCollege of Business AdministrationCalifornia State UniversityStanislausTurlockCA95382United States Institute of Supply Chain Analytics&International Business College Dongbei University of Finance and EconomicsDalian 116025China

With the rapid development of information technology and fast growth of Internet users,e-commerce nowadays is facing complex business environment and accumulating large-volume and highdimensional data.This brings two challenges for demand forecasting.First,e-merchants need to find appropriate approaches to leverage the large amount of data and extract forecast features to capture various factors affecting the demand.Second,they need to efficiently identify the most important features to improve the forecast accuracy and better understand the key drivers for demand changes.To solve these challenges,this study conducts a multi-dimensional feature engineering by constructing five feature categories including historical demand,price,page view,reviews,and competition for e-commerce demand forecasting on item-level.We then propose a two-stage random forest-based feature selection algorithm to effectively identify the important features from the high-dimensional feature set and avoid overfittlng.We test our proposed algorithm with a large-scale dataset from the largest e-commerce platform in China.The numerical results from 21,111 items and 109 million sales observations show that our proposed random forest-based forecasting framework with a two-stage feature selection algorithm delivers 11.58%,5.81%and 3.68%forecast accuracy improvement,compared with the Autoregressive Integrated Moving Average(ARIMA),Random Forecast,and Random Forecast with one-stage feature selection approach,respectively,which are widely used in literature and industry.This study provides a useful tool for the practitioners to forecast demands and sheds lights on the B2C e-commerce operations management.

关键词： Forecasting e-commerce high-dimensional feature feature selection

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关于新时代弘扬科学精神工作的几点思考

今日科苑 2024年第4期 78-85页

作者：董亚峥张亦旒鲍妮娜中国科协科学技术传播中心北京100012

新时代在解决科技支撑发展、公民科学素质进一步提升等问题时,弘扬科学精神都是重要的内容。文章分析了关于科学精神的理论研究和社会实践面临的挑战,从科学精神的概念体系入手,分析了新时代弘扬科学精神的关注重点,并对具体工作提出建... 详细信息

新时代在解决科技支撑发展、公民科学素质进一步提升等问题时,弘扬科学精神都是重要的内容。文章分析了关于科学精神的理论研究和社会实践面临的挑战,从科学精神的概念体系入手,分析了新时代弘扬科学精神的关注重点,并对具体工作提出建议,包括弘扬科学家精神、一流学术传统构建、人类命运共同体构建、文化自信等内容。

关键词：科学精神科学家精神一流学术传统人类命运共同体文化自信

Aeration performances and air—Water mass transfer on steep stepped weirs with horizontal and inclined steps

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Journal of Hydrodynamics 2022年第5期34卷 904-916页

作者： Yvan Arosquipa nina Rui Shi Davide Wüthrich Hubert Chanson The University of Queensland School of Civil EngineeringBrisbaneAustralia Department of Hydraulic Engineering Delft University of TechnologyDelftThe Netherlands

At hydraulic structures,some strong interactions may develop between fast flowing waters and the air adjacent to the water in motion that enhance the air-water transfer of atmospheric and volatile gases in the flow.In turn,in-stream structures may contribute to the aeration and re-oxygenation during overflow.The present study aims to characterize the aeration performance of a steep stepped weir,based upon a detailed physical investigation of air-water interfacial properties across a relatively wide range of discharges.The data showed a strong fragmentation of the air-water flows,a very broad range of entrained bubbles and drops,and a large amount of particle clustering.The results implied a monotonic increase in re-aeration with increasing rate of energy dissipation,while the largest aeration efficiency was observed on the horizontal step weir chute,with the smallest on the 1V:2.33H inclined downward steps.Altogether,the study showed that a steep stepped chute can make a sizeable contribution to the re-oxygenation of the waters,although the downward inclined steps reduce the re-aeration performances.

关键词： Stepped weirs aeration re-oxygenation physical modeling flow fragmentation

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助产学课程主题情境教学实践

中华护理教育 2024年第1期21卷 53-56页

作者：谢颖高燕戴小红蒋妮娜肖雪军戴云云桂林医学院护理学院桂林市541000

该文阐述了助产学课程教学创新与实践,介绍了在主题情境思维框架下重构助产知识结构、建设情境教学资源、构建“知识-情景-问题”链路式教学路径。该课程经多年教学改革已获批广西壮族自治区线下一流本科课程,授课教师荣获区级高校教师... 详细信息

该文阐述了助产学课程教学创新与实践,介绍了在主题情境思维框架下重构助产知识结构、建设情境教学资源、构建“知识-情景-问题”链路式教学路径。该课程经多年教学改革已获批广西壮族自治区线下一流本科课程,授课教师荣获区级高校教师教学创新大赛二等奖,可为助产学课程建设、提升助产专业学生临床思维能力提供参考。

关键词：教育,护理助产学情境教学