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培养条件对小鼠骨髓基质集落形成细胞在体外生长的影响 被引量:1
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作者 徐承熊 韩锐 《中国医学科学院学报》 CAS CSCD 北大核心 1990年第4期257-261,共5页
对一些可能影响小鼠CFU—f集落形成率的因素进行了研究。这些因素包括培养基、血清、培养皿、小鼠品系以及培养容器中的氧浓度。研究发现,在诸因素中以氧浓度最为关键。用含5%O_2、5%CO_2及90%N_2的混合气体代替含5%CO_2空气不仅使... 对一些可能影响小鼠CFU—f集落形成率的因素进行了研究。这些因素包括培养基、血清、培养皿、小鼠品系以及培养容器中的氧浓度。研究发现,在诸因素中以氧浓度最为关键。用含5%O_2、5%CO_2及90%N_2的混合气体代替含5%CO_2空气不仅使CFU—f的集落形成率明显提高,而且可减轻其它因素对细胞生长的影响。用燃烛法消耗空气中的氧虽可使某些肿瘤细胞系在软琼脂中形成集落,但不利于CFU—f生长。 展开更多
关键词 造血微环境 质集荔形成 氧浓度
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株洲先进硬质材料产业集群数字化高技能人才培养路径
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作者 王红亮 陈燕彬 席莉 《太原城市职业技术学院学报》 2024年第7期32-34,共3页
数字化高技能人才是数字经济时代产业集群转型升级的核心驱动力。相关调研数据显示,先进硬质材料产业集群对高技能人才的数字化能力提出了新的要求。高职院校人才培养模式要适应数字化的变革与转型,通过设定数字化人才培养目标、创新课... 数字化高技能人才是数字经济时代产业集群转型升级的核心驱动力。相关调研数据显示,先进硬质材料产业集群对高技能人才的数字化能力提出了新的要求。高职院校人才培养模式要适应数字化的变革与转型,通过设定数字化人才培养目标、创新课程体系建设、培育双师型师资队伍、深化校企合作办学等路径,为先进硬质材料产业集群输出更多高质量的数字化高技能人才。 展开更多
关键词 材料产业 产教融合 数字化人才
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浅谈智能化快速部署医院健康档案数据集质量控制 被引量:3
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作者 王浩 周娟 +3 位作者 曾雪 孟祥峰 张超 李佳戈 《中国医疗设备》 2021年第9期11-14,共4页
目的研究健康档案数据集的质量控制策略,旨在促进该领域的人工智能医疗器械专用标准规范。方法根据健康档案数据集的技术特点和开发场景,对此类数据集的特殊性进行分析,梳理质控要点;采用不同方法,对具体的数据模态开展抽样检验实验,比... 目的研究健康档案数据集的质量控制策略,旨在促进该领域的人工智能医疗器械专用标准规范。方法根据健康档案数据集的技术特点和开发场景,对此类数据集的特殊性进行分析,梳理质控要点;采用不同方法,对具体的数据模态开展抽样检验实验,比较和评估资源消耗。结果与生产验收抽验方法相比,质量监督抽验方法需要的样本量更低,更具有经济性和可行性。结论本文研究的思路和方法有助于促进健康档案数据集的质量控制,加速智能化快速部署医院等特殊情景的数据集建设。 展开更多
关键词 人工智能医疗器械 健康档案 数据 智能化快速部署医院
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多状态系统故障树质蕴含集的求取算法 被引量:1
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作者 曾亮 《国防科技大学学报》 EI CAS CSCD 1997年第5期70-75,共6页
本章首先给出多状态系统状态空间的立方体表示方法,然后建立相应的运算规则。在这些规则的基础上,提出多状态系统故障树质蕴含集的求取算法。通过实例分析,说明了这种方法的可行性。
关键词 多状态系统 故障树 蕴含 立方体
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视觉识别系统联合集束化质控策略在神经外科鼻胃管喂养管理中的应用
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作者 张琴 潘璐 《中国乡村医药》 2020年第8期69-70,共2页
目的观察视觉识别系统联合集束质控策略在神经外科鼻胃管喂养管理中的应用效果。方法2018年1月至2019年2月该院神经外科接受鼻胃管喂养患者120例,按入院时间先后分为对照组与观察组各60例。对照组给予鼻胃管喂养常规护理,观察组给予视... 目的观察视觉识别系统联合集束质控策略在神经外科鼻胃管喂养管理中的应用效果。方法2018年1月至2019年2月该院神经外科接受鼻胃管喂养患者120例,按入院时间先后分为对照组与观察组各60例。对照组给予鼻胃管喂养常规护理,观察组给予视觉识别系统联合集束化质控策略干预,比较两组干预后鼻胃管喂养关键管理措施落实率、一次置管成功率、给药错误率、置管错位发生率。结果观察组鼻胃管喂养各项关键管理措施落实率明显高于对照组,一次置管成功率(96.7%)明显高于对照组(86.7%),给药错误率与鼻胃管置管错位发生率明显低于对照组,差异有统计学意义(P<0.05)。结论采用视觉识别系统联合集束化质控策略对神经外科鼻胃管喂养者开展管理,可有效提高鼻胃管喂养安全有效性。 展开更多
关键词 视觉识别系统 束化 神经外科 鼻胃管喂养
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榫卯结构三角支撑轻质薄板安全多旋翼飞行器
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作者 徐知非 《信息技术与信息化》 2017年第12期54-60,共7页
针对多旋翼飞行器训练中存在的飞行安全、设备昂贵、组装维修繁琐的状况,受中国木结构建筑的启发,把中国最古老的柔性框架结构技术——-榫卯结构三角支撑用于现代飞行器制造,发明出基于榫卯结构三角支撑、KT板式轻质薄板的安全多旋翼飞... 针对多旋翼飞行器训练中存在的飞行安全、设备昂贵、组装维修繁琐的状况,受中国木结构建筑的启发,把中国最古老的柔性框架结构技术——-榫卯结构三角支撑用于现代飞行器制造,发明出基于榫卯结构三角支撑、KT板式轻质薄板的安全多旋翼飞行器。该飞行器主要包括机身、旋翼、位于机身中部的飞行控制模块以及集成线束式的连接线。机身由若干块轻质垂直结构板榫卯插接组成的框架,在垂直结构板最外侧相交处的竖直方向设有旋翼。和框架垂直面连接有固定用的水平结构板,水平结构板上以旋翼电机轴为圆心,设有若干保护旋翼用略大于旋翼直径的圆形旋翼孔,该孔既保护底部电源控制模块,又增加机身整体强度,旋翼安装在水平结构板的旋翼孔内,有效地保证了设备和人身安全。改进后的多旋翼飞行器具有结构坚固、安装简单、安全可靠、线路集成、成本低廉的优点,解决了当今多旋翼飞行器结构复杂、安装繁琐、碳纤材质单一、维修成本昂贵和飞行训练中人身及设备的安全问题。适合多旋翼飞行培训教学使用,具有广泛的推广应用价值。 展开更多
关键词 多旋翼飞行器 榫卯结构 三角支撑 薄板成化动力系统 安全 低成本
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条件独立性的三种形式及其相互关系 被引量:9
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作者 李开灿 耿直 《北京大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第5期629-634,共6页
给出了随机变量的随机条件独立性、回归条件独立性及其强随机条件独立性的概念 ,并且证明了这几种条件独立性的相互关系。主要结论是在一定条件下 ,强随机条件独立必有回归条件独立 ;随机条件独立性与回归条件独立性是等价的。它们对概... 给出了随机变量的随机条件独立性、回归条件独立性及其强随机条件独立性的概念 ,并且证明了这几种条件独立性的相互关系。主要结论是在一定条件下 ,强随机条件独立必有回归条件独立 ;随机条件独立性与回归条件独立性是等价的。它们对概率论及其数理统计的应用是有意义的。 展开更多
关键词 条件独立性 Σ-域 条件期望 质集 概率论 随机变量 概率空间 数理统计
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Mechanical properties of epoxy asphalt mixture pavement with lightweight aggregate applied on bascule bridge 被引量:1
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作者 刘云 钱振东 +1 位作者 张磊 江陈龙 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期321-326,共6页
The high temperature anti-rutting performance,water stability and low temperature bending property of epoxy asphalt mixture with 0%,15%,25%,40%,and 70% granulated and circular lightweight aggregates by weight are test... The high temperature anti-rutting performance,water stability and low temperature bending property of epoxy asphalt mixture with 0%,15%,25%,40%,and 70% granulated and circular lightweight aggregates by weight are tested,respectively.The dynamic responses under the vehicle load and in the opening process are analyzed to obtain the mechanical responses of pavements by using the finite element method.The complicated structure including a steel deck and a waterproof adhesive layer is made to verify the bond strength of the 2451-type epoxy asphalt binder.Research results show that the epoxy asphalt mixtures with lightweight aggregate replacement percentages from 0% to 70% all satisfy the requirements for steel bridge pavements.The epoxy asphalt mixture with a 70% circular lightweight aggregate replacement percentage is recommended because of its smaller density when compared with other epoxy asphalt mixtures.The shear stress increases with the increase in the opening angle and achieves its maximum at the maximum opening angle of 85°.Test results show that the Tianjin Bascule Bridge can be used for first opening after a 3 d pavement conditioning. 展开更多
关键词 bascule bridge steel bridge deck pavement lightweight aggregate mechanical response shear stress
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A Novel Lateral Solenoidal On-Chip Integrated Inductor Implemented in Conventional Si Process 被引量:1
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作者 刘畅 陈学良 +1 位作者 严金龙 顾伟东 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第4期352-365,共14页
A new structure of the on- chip integrated inductors im plem ented in conventional Si process is presented as a lateral solenoid.The fabrication process utilizes a conventional Si technology with standard double- lay... A new structure of the on- chip integrated inductors im plem ented in conventional Si process is presented as a lateral solenoid.The fabrication process utilizes a conventional Si technology with standard double- layer m etal- lization.S param eters of the inductors based equivalent circuit are investigated and the inductor parameters are cal- culated from the m easured data.Experimental results are presented on an integrated inductors fabricated in a lateral solenoid type utilizing double m etal layers rather than a single metal layer as used in conventional planar spiral de- vices.Inductors with peak Q of 1.3and inductance value of 2 .2 n H are presented,which are com parable to conven- tional planar spiral inductors. 展开更多
关键词 integrated inductor solenoidal inductor spiral inductor quality factor
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INTEGRATION OF HUMAN FACTORS ENGINEERING AND QUALITY MANAGEMENT 被引量:1
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作者 卢岚 秦嵩 +1 位作者 陆全 Dessouky MohomedI 《Transactions of Tianjin University》 EI CAS 2001年第3期178-181,共4页
Human factors engineering and quality management are different research branches in the field of industrial engineering.A basis for interaction based on the concepts and techniques of human factors engineering and qua... Human factors engineering and quality management are different research branches in the field of industrial engineering.A basis for interaction based on the concepts and techniques of human factors engineering and quality management with some practical examples of cooperative effect is defined in this paper.The specific challenges about the quality management in manufacturing and service are presented to demonstrate that the human factors analysis of quality problems leads to new tends for integrated development. 展开更多
关键词 human factors engineering quality management integrated development cooperative effect
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Novel Substrate pn Junction Isolation for RF Integrated Inductors on Silicon 被引量:5
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作者 刘畅 陈学良 严金龙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第12期1486-1489,共4页
A new method for reducing the substrate rated losses of integrated spiral inductors is presented.The method is to block the eddy currents induced by spiral inductors by directly forming pn junction isolation in the S... A new method for reducing the substrate rated losses of integrated spiral inductors is presented.The method is to block the eddy currents induced by spiral inductors by directly forming pn junction isolation in the Si substrate. The substrate pn junction can be realized by using the standard silicon technologies without any additional processing steps.Integrated inductors on silicon are designed and fabricated. S parameters of the inductor based equivalent circuit are investigated and the inductor parameters are calculated.The impacts of the substrate pn junction isolation on the inductor quality factor are studied.The experimental results show that substrate pn junction isolation in certain depth has achieved a significant improvement.At 3GHz,the substrate pn junction isolation increases the inductor quality factor by 40%. 展开更多
关键词 Si integrated inductor quality factor eddy current pn junction isolation
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一起水污染事件的吹扫捕集-气相色谱-质谱的分析结果 被引量:3
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作者 张宏斌 胡斌 《职业与健康》 CAS 2011年第3期291-292,共2页
2010年7月29日,昆山市疾病预防控制中心接某乡镇打工楼的某公司职工反映,该宿舍楼自来水有异味,部分职工饮用后出现恶心反应,本中心接报后立即赶赴现场调查处理。该宿舍楼二期工程(5、6、7号楼)刚于本月初竣工,某公司职工90人于2周前... 2010年7月29日,昆山市疾病预防控制中心接某乡镇打工楼的某公司职工反映,该宿舍楼自来水有异味,部分职工饮用后出现恶心反应,本中心接报后立即赶赴现场调查处理。该宿舍楼二期工程(5、6、7号楼)刚于本月初竣工,某公司职工90人于2周前入住,现场调查发现,(5、6、7号楼)各楼层自来水末梢水均有油漆味,刚开启时尤甚,放水一段时间后气味减轻,而一期工程的宿舍(1、2、3、4号楼)、食堂等处自来水未发现异味。 展开更多
关键词 水污染事件 吹扫捕-气相色谱-谱分析
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Neighborhood Union of Essential Sets and Hamiltonicity of Claw-Free Graphs
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作者 徐新萍 《Journal of Southeast University(English Edition)》 EI CAS 2002年第2期184-187,共4页
Let G be a graph, an independent set Y in G is called an essential independent set (or essential set for simplicity), if there is {y 1,y 2} Y such that dist (y 1,y 2)=2. In this paper, we wi... Let G be a graph, an independent set Y in G is called an essential independent set (or essential set for simplicity), if there is {y 1,y 2} Y such that dist (y 1,y 2)=2. In this paper, we will use the technique of the vertex insertion on l connected ( l=k or k+1,k≥2 ) claw free graphs to provide a unified proof for G to be hamiltonian or 1 hamiltonian, the sufficient conditions are expressed by the inequality concerning ∑ki=0N(Y i) and n(Y) for each essential set Y={y 0,y 1,...,y k} of G , where Y i={y i,y i-1 ,...,y i-(b-1) }Y for i∈{0,1,...,k} (the subscriptions of y j ’s will be taken modulo k+1 ), b ( 0【b【k+1 ) is an integer, and n(Y)={v∈V(G): dist (v,Y)≤2 }. 展开更多
关键词 HAMILTONICITY claw free graph neighborhood union vertex insertion essential set
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咸阳中国画院作品选
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作者 张路 《人文杂志》 1987年第4期2-129,共2页
咸阳是周秦汉唐灿烂文化的发祥地,自古就是诗文书画之乡,现在已经成为一座焕发青春、放射异彩的明星城市。 咸阳中国画院是在逆境中崛起的一个艺术群体。当代中国画正处在一个“更新换代”
关键词 咸阳 中国画 作品选 周秦汉唐 焕发青春 发祥地 质集 明星 文书 当代中国
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GEOTHERMAL RESOURCES ASSESSMENT AND NUMERICAL SIMULATION IN TUANBO REGION
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作者 朱家玲 李春华 高天真 《Transactions of Tianjin University》 EI CAS 2001年第4期251-254,共4页
This paper mainly deals with the reservoir on the heat and mass transfer and mass and energy balance in a geothermal field.On the basis of briefing the general characteristics of the reservoir and the supposition of t... This paper mainly deals with the reservoir on the heat and mass transfer and mass and energy balance in a geothermal field.On the basis of briefing the general characteristics of the reservoir and the supposition of the reservoir modeling,the paper emphasizes the mathematical descriptions of hydra thermal transportation and convection by two methods according to the different models,such as lumped parameter model and distributed parameter model.It is effective to use these models in simulating the heterogeneous,and anisotropical fracture reservoir for the designed lifetime of 15 years. 展开更多
关键词 assessment of geothermal resources mass and energy balance lumped parameter model distributed parameter model
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Researches on Extraction,Purification Technique and Properties of Lectin from Porphyra yezoensis
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作者 盘赛昆 张林维 胡赛泉 《Agricultural Science & Technology》 CAS 2010年第8期129-132,136,共5页
[Objective] The aim was to explore the extraction technique and purification method of lectin from Porpya yezoensis,as well as to investigate the properties of lectin. [Method] The effects of four factors such as buff... [Objective] The aim was to explore the extraction technique and purification method of lectin from Porpya yezoensis,as well as to investigate the properties of lectin. [Method] The effects of four factors such as buffer system,solid-liquid ratio,temperature,and extracting time on the lectin extraction result from P. yezoensis were investigated by the use of specific activity as the indicator. Then the lectin was purified by DEAE-Sepharose FF chromatography. The hemagglutination activity was used as the indicator,and the properties of the lectin such as carbohydrate specificity,divalent cations dependence,temperature,acidic and alkaline stability and others were detected. [Result] The optimal extraction conditions were:extraction ageat Tris-HCl buffer (25 mmol/L,pH=7.5 ),solid-liquid ratio of 1:5,extracting temperature of 40 ℃,and extracting time of 16 h. The activity of the lectin of P. yezoensis didn't change after 30 min of being heated at 50 ℃,which showed a certain extent of thermal stability,and the suitable pH value was 7-9. The lectin of P. yezoensis could combine with maltose,D-galactose,D-xylose and L-Arabinose,in which the binding force with the maltose was the strongest. The lectin activity was depended on the addition of Ca2+ and Mg2+. [Conclusion] The research had provided theoretical basis for the clarification of immune mechanism of P. yezoensis,as well as its high effective utilization. 展开更多
关键词 Porphyra yezoensis LECTIN EXTRACTION PROPERTIES
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实现非单调关联故障树PIS的联合技术 被引量:1
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作者 罗泽林 任强 罗航 《计算机应用》 CSCD 北大核心 2011年第11期3143-3148,共6页
采用"非正规"二元决策图(BDD)技术获取最小形割集(MCS)可能存在掩盖非单调底事件作用的弊端"。以"继承"关键技术为基础,提出了用统一编码的"正规"BDD技术来获取非单调关联故障树的MCS。结合Q-M算法... 采用"非正规"二元决策图(BDD)技术获取最小形割集(MCS)可能存在掩盖非单调底事件作用的弊端"。以"继承"关键技术为基础,提出了用统一编码的"正规"BDD技术来获取非单调关联故障树的MCS。结合Q-M算法,研究了联合获取非单调关联故障树的质蕴涵集(PIS)的完整过程。实际例证表明,所述方法不但能够准确地析出非单调关联故障树的MCS,而且能够自动地获取其PIS。 展开更多
关键词 故障树 蕴含 非单调 二元决策图 继承 合并
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Fracture prediction using prestack Q calculation and attenuation anisotropy 被引量:1
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作者 安勇 《Applied Geophysics》 SCIE CSCD 2015年第3期432-440,469,共10页
The analysis of fractured reservoirs is very important to hydrocarbon exploration. The quality factor Q is a parameter used to characterize the attenuation of seismic waves in subsurface media. Q not only reflects the... The analysis of fractured reservoirs is very important to hydrocarbon exploration. The quality factor Q is a parameter used to characterize the attenuation of seismic waves in subsurface media. Q not only reflects the inherent properties of the medium but also is used to make predictions regarding reservoir fractures. Compared with poststack seismic data, prestack seismic data contain detailed stratigraphic information of seismic attributes and data inversion in reservoirs. The extraction of absorption parameters from prestack data improves the accuracy of attenuation estimates. In this study, I present a new method for calculating Q based on the modified S transform (MST) using common midpoint (CMP) preprocessed gathers. First, I use the MST with adjustable time-frequency resolution to carry out a high-precision time-frequency analysis of prestack CMP gathers and derive the calculation formula for the improved S transform-based frequency spectrum ratio method. Then, I use the energy density ratio to calculate the slope of the frequency spectrum ratio instead of the conventional amplitude ratio. Thus, I establish the relation between the slope of the spectrum ratio and offset as well as eliminate the offset effect by multichannel linear fitting, obtaining accurate Q values from seismic prestack data. Finally, I use the proposed prestack Q extraction method to study the fractured reservoir in Qianjin burried hill and P-wave absorption and attenuation anisotropy with good results in the fracture characterization. 展开更多
关键词 FRACTURE ATTENUATION quality factor MST CMP gather
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Some properties of monotone set functions defined by Choquet integral 被引量:4
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作者 欧阳耀 李军 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期423-426,共4页
In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-ad... In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-additivity, strong order continuity, property (s) andpseudomelric generating property, etc., are preserved by the new set function. It is also shown thatC-integrability assumption is inevitable for the preservations of strong order continuous andpseudometric generating property. 展开更多
关键词 non-additive measure monotone set function choquet integral
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岛屿硬化集水面雨水弃流方案与分质收集策略研究 被引量:1
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作者 杨伟伟 孟颖 +4 位作者 袁庆科 姚国庆 郑雨 栾富波 徐大勇 《环境科学学报》 CAS CSCD 北大核心 2021年第11期4585-4595,共11页
通过研究海南岛文昌市水泥屋顶和水泥路面上的雨水径流特征,建立了岛屿地区不同硬化集水面的雨水弃流方案和分质收集策略.在降雨初期,水泥路面和水泥屋顶均发生明显的冲刷效应,水泥路面雨水径流污染物浓度远高于水泥屋顶,且不同硬化集... 通过研究海南岛文昌市水泥屋顶和水泥路面上的雨水径流特征,建立了岛屿地区不同硬化集水面的雨水弃流方案和分质收集策略.在降雨初期,水泥路面和水泥屋顶均发生明显的冲刷效应,水泥路面雨水径流污染物浓度远高于水泥屋顶,且不同硬化集水面上前30%雨水中的污染物浓度均高于后70%的雨水.通过与相关水质指标对比得出,水泥屋顶雨水径流可作为饮用水水源,水泥路面雨水径流经处理可作为城市杂用水使用.通过建立雨水径流污染物累积⁃冲刷经验模型,可计算不同硬化集水面的弃流雨量,并以此为依据制定了弃流方案.以两种典型硬质化集水面径流污染物传输特征、水质特征和弃流方案为基础,分别提出了屋顶雨水收集方案和多种生态方法协同作用的路面雨水收集方案,可为岛屿地区的雨水收集利用方案提供参考依据. 展开更多
关键词 岛屿地区 水面 雨水弃流
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