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Eco-environmental benefit assessment of China's South-North Water Transfer Scheme——the middle route project
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作者 DUANGuang-ming ZHAOJing-zhu LIUGuo-hua KEBing XIAOHan WUGang DENGHong-bing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第2期308-315,共8页
This paper assess the eco-environmental benefits that may come from the middle route project of China's South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of ... This paper assess the eco-environmental benefits that may come from the middle route project of China's South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of SNWT's middle route project. Some benefits were calculated in monetary units. To make sure that the results can be comparable with normal monetary indices, concrete assessment objects and the parameters are prudently selected according to the major characteristics of the project and its water import region. Primary assessment revealed that in different project construction stages, the benefit could be more than 13 07 billion RMB Yuan in 2010 and 19 79 billion RMB Yuan in 2030, respectively. The monetary value tends to increase with social-economic development. To realize these potential benefits, however, calls for more endeavors. 展开更多
关键词 China's South-North Water transfer scheme(SNWT) the middle route project of South-North Water transfer(MRPSNWT) assessment ecosystem services monetary indices
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Estimating minimum ecological water required of the western route first stage project of China's south-to-north water transfer scheme for water exporting rivers
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作者 MEN Bao-hui 《Journal of Environmental Science and Engineering》 2007年第1期19-24,共6页
It is well known that there is abundant water resources in basin of the Yangtze River, the first largest river in China, which is mainly located in Southern China. However, water resources is very scarce in the basin ... It is well known that there is abundant water resources in basin of the Yangtze River, the first largest river in China, which is mainly located in Southern China. However, water resources is very scarce in the basin of the Yellow River, which is mainly located in Northern China. So the western route project of south-north water transfer scheme (WRP-SNWTS) aims to transfer water from the Yangtze River to the Yellow River. The area of WRP-SNWT, located in the upper reaches of the Yangtze River and the main areas of Sichuan and the marginal areas of the Qinghai-Tibet Plateau, has sufficient water resources but fragile ecology and environment. Therefore, it is necessary for WRP-SNWT to analyze the ecology water required. Based on the planning principles of from low elevation to high elevation, from small to large, from short to long and from easy to difficulty, the WRP-SNWT will be constructed through three stage projects. The western route first stage project of the south-north water transfer scheme (WRFST-SNWTS) is planned to transfer 4×10^9m^3/a from six tributaries of the Yalong river and from Dadu river to Jiaqu of Yellow River.. Daqu river and Niqu river are the branches of Xianshui river. Sequ river, Duke river, Make river and Ake river are the branches of Dadu river, which account for 65-70% of the total river run-off. It need more research and the rest run-off can satisfy channel ecology water required. According to analysis ecological water required which mainly satisfy for aquicolous biology in water-exporting region, such as low air temperature. Fish and aquicolous biology main living from May to August, and rivers are iced up from December to March of next year, ecology water required mainly for fish and aquicolous biology. The flow criterion of Tennant method is modified. The ecology water required of WRFSP-SNWTS is estimated by the flow data of Zhuwo gauging station, Zhuba gauging station, Chuosijia gauging station and Zumuzu gauging station. The result show that the ecology water required calculated by modified Tennant less 1 l percent than that of Tennant. This estimating result can supply more water resources for transferring to Yellow River. Meanwhile, this can supply gist for research transferring water of WRFSP-SNWTS. 展开更多
关键词 Yangtze River Yellow River western route first stage project of the south-north water transfer scheme minimum ecological water required Tennant method
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Need for operational simplicity and timely disbursal of benefits—a qualitative exploration of the implementation of a direct benefit transfer scheme for persons with tuberculosis in India
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作者 Malu Mohan Jeromie W.V.Thangaraj +17 位作者 Sumit Pandey G.Sri Lakshmi Priya Sivavallinathan Arunachalam Rahul Sharma Hemant Deepak Shewade B.Aishwarya K.Afeeq Afsana Khatoon B.Gokulvijay Gude Sireesha Kavita Chandra S.Nandhakumar Prince Samuel C.Nanditha Viswanathan Devika Shanmugasundaram Raghuram Rao Manoj V.Murhekar Kathiresan Jeyashree 《Infectious Diseases of Poverty》 SCIE CAS CSCD 2024年第3期58-72,共15页
Background Ni-kshay Poshan Yojana(NPY)is a direct benefit transfer scheme of the Government of India introduced in 2018 to support the additional nutritional requirements of persons with TB(PwTB).Our recent nationwide... Background Ni-kshay Poshan Yojana(NPY)is a direct benefit transfer scheme of the Government of India introduced in 2018 to support the additional nutritional requirements of persons with TB(PwTB).Our recent nationwide evaluation of implementation and utilization of NPY using programmatic data of PwTB from nine randomly selected Indian states,reported a 70%coverage and high median delay in benefit credit.We undertook a qualitative study between January and July 2023,to understand the detailed implementation process of NPY and explore the enablers and barriers to effective implementation and utilization of the NPY scheme.Methods We followed a grounded theory approach to inductively develop theoretical explanations for social phenomena through data generated from multiple sources.We conducted 36 in-depth interviews of national,district and field-level staff of the National Tuberculosis Elimination Programme(NTEP)and NPY beneficiaries from 30 districts across nine states of India,selected using theoretical sampling.An analytical framework developed through inductive coding of a set of six interviews,guided the coding of the subsequent interviews.Categories and themes emerged through constant comparison and the data collection continued until theoretical saturation.Results Stakeholders perceived NPY as a beneficial initiative.Strong political commitment from the state administration,mainstreaming of NTEP work with the district public healthcare delivery system,availability of good geographic and internet connectivity and state-specific grievance redressal mechanisms and innovations were identified as enablers of implementation.However,the complex,multi-level benefit approval process,difficulties in accessing banking services,perceived inadequacy of benefits and overworked human resources in the NTEP were identified as barriers to implementation and utilization.Conclusion The optimal utilization of NPY is enabled by strong political commitment and challenged by its lengthy implementation process and delayed disbursal of benefits.We recommend greater operational simplicity in NPY implementation,integrating NTEP activities with the public health system to reduce the burden on the program staff,and revising the benefit amount more equitably. 展开更多
关键词 National Tuberculosis Elimination Programme Nutritional status Direct benefit transfer IMPLEMENTATION Cash transfer scheme Grounded theory INDIA
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Delay Effect on Coherent Transfer of Optical Frequency Based on a Triple-Pass Scheme 被引量:1
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作者 Chao-qun Ma Li-Fei Wu +2 位作者 Jiao Gu Yan-He Chen Guo-Qing Chen 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第8期9-13,共5页
We demonstrate a triple-pass scheme for coherent transfer of optical frequency and the delay effect on the fiber phase noise compensation. It is theoretically proved that the delay effect consists of both fiber delay ... We demonstrate a triple-pass scheme for coherent transfer of optical frequency and the delay effect on the fiber phase noise compensation. It is theoretically proved that the delay effect consists of both fiber delay and servo delay. The delay effect confines the servo bandwidth within 1/8 and induces a residual fiber phase noise after noise compensation. For a 25-km-long fiber, the servo bandwidth is found to be around 1 k Hz, and the fiber phase noise is suppressed approaching to the theoretical limitation. The triple-pass scheme enables the simultaneous transfer of optical frequency to multiple remote users. The performance of noise compensator in the triple-pass scheme can achieve a similar level result compared with that in the double-pass scheme. 展开更多
关键词 Delay Effect on Coherent transfer of Optical Frequency Based on a Triple-Pass scheme AOM
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S-scheme活性炭负载g-C_(3)N_(4)/TiO_(2)光催化混凝土降解性能分析 被引量:2
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作者 张典 《无机盐工业》 北大核心 2025年第4期118-127,共10页
为了解决抗生素废水污染和室内装修低浓度甲醛污染,采用简易的混合高温煅烧法制备了活性炭负载g-C_(3)N_(4)/TiO_(2)(g-C_(3)N_(4)/TiO_(2)/AC)复合光催化剂。通过XRD、XPS、TEM、UV-vis DRS和PL等技术对复合光催化剂的物相晶型、元素... 为了解决抗生素废水污染和室内装修低浓度甲醛污染,采用简易的混合高温煅烧法制备了活性炭负载g-C_(3)N_(4)/TiO_(2)(g-C_(3)N_(4)/TiO_(2)/AC)复合光催化剂。通过XRD、XPS、TEM、UV-vis DRS和PL等技术对复合光催化剂的物相晶型、元素组成、微观形貌、光谱响应范围和光生载流子重组等进行了表征。S-scheme异质结弯曲能带和内电场实现了光生载流子的高效分离,拓宽了光谱吸收范围,有效保留了高活性的·O_(2)^(-)、h^(+)和·OH等活性基团,表现出优异的磺胺甲基噻唑(STZ)降解活性和稳定性,g-C_(3)N_(4)/TiO_(2)/AC投加量为1.0 mg和STZ初始质量浓度为100 mg/L条件下,可见光照射30 min时STZ降解率为98.8%,明显优于g-C_(3)N_(4)、TiO_(2)和TiO_(2)/AC。g-C_(3)N_(4)/TiO_(2)/AC掺杂到环氧树脂涂料中合成了光催化涂料,通过空气喷枪均匀喷涂到混凝土表面得到光催化混凝土,光催化混凝土表现出良好的甲醛降解活性和稳定性,g-C_(3)N_(4)/TiO_(2)/AC负载量为3%、甲醛初始质量浓度为1000 mg/L、可见光照射180 min时,甲醛降解率达到了96.3%,有效实现了室内装修低浓度甲醛气体的高效降解。 展开更多
关键词 g-C_(3)N_(4) TiO_(2) 光催化 混凝土 S-scheme电荷转移机制 抗生素降解 室内装修甲醛降解
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宁波市轨道交通5号线一期三官堂站换乘方案研究
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作者 何耀武 《现代工程科技》 2026年第1期49-52,共4页
随着城市轨道交通的快速发展,城市轨道交通线网系统覆盖范围越来越大,线网交织产生越来越多的换乘车站,由此出现了既有高架站与新建地下站换乘的情况。此外,为提高土地利用率,增加轨道交通带来的经济效应,为城市发展注入新的活力,地铁... 随着城市轨道交通的快速发展,城市轨道交通线网系统覆盖范围越来越大,线网交织产生越来越多的换乘车站,由此出现了既有高架站与新建地下站换乘的情况。此外,为提高土地利用率,增加轨道交通带来的经济效应,为城市发展注入新的活力,地铁车站与物业开发相结合的建设形式也备受青睐。以宁波轨道交通三官堂站为例,分析了本站换乘方案重难点,对换乘方案进行比选,研究车站与物业结合的形式,详细论述了既有高架站与新建地下站换乘并与物业相结合的车站方案设计要点,为后续类似案例提供借鉴。 展开更多
关键词 地铁 地上车站 地下车站 换乘方案 物业开发
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有限容积方法数值求解声子玻尔兹曼方程中的偏置误差及其影响规律
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作者 冯相友 陶文铨 《西安交通大学学报》 北大核心 2026年第1期81-93,共13页
为了进一步厘清有限容积方法(FVM)在数值求解声子玻尔兹曼方程(BTE)中的误差机制,在普遍认为的假散射和射线效应误差外,发现了一种新的误差来源——偏置误差,并分析了其影响规律。首先,基于两个热传导算例中的温度、热流计算偏差的分析... 为了进一步厘清有限容积方法(FVM)在数值求解声子玻尔兹曼方程(BTE)中的误差机制,在普遍认为的假散射和射线效应误差外,发现了一种新的误差来源——偏置误差,并分析了其影响规律。首先,基于两个热传导算例中的温度、热流计算偏差的分析,定义了偏置误差的概念。偏置误差是在采用迎风偏置格式离散对流项时,同一界面上不同方向声子能量所取上游节点不同,所产生的热流计算偏差。然后,对偏置误差的影响因素进行了分析。最后,探究了高阶格式特征线分布对偏置误差的影响规律。结果表明:影响偏置误差的因素主要有3个,即网格克努森数Kn_(Δ)(声子平均自由程与网格宽度的比值)、格式的偏置特性、结果的分布线型;在一般情况下,算例的1/Kn_(Δ)越大、所用离散格式特征线偏离零偏置线的程度越大、结果线型的非线性越强,其偏置误差越大;偏置误差的影响趋势可以由格式特征线偏离零偏置线的方向定性确定,若格式特征线在零偏置线之下,偏置误差会导致计算中高估热流,格式特征线在零偏置线之上则相反。该研究为声子BTE在求解微纳尺度传热问题中,合理选择对流项离散格式和结果的误差评估提供了理论支持。 展开更多
关键词 声子玻尔兹曼方程 有限容积方法 偏置误差 离散格式 微纳尺度传热
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步进式加热炉炉底平移框架梁体开裂原因分析与加固方案研究
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作者 赵立勇 刘璇 韩腾飞 《工业加热》 2026年第1期63-70,共8页
步进式加热炉作为一种加热设备在金属加工行业广泛应用,步进梁作为其机械传动部件,在长期往复循环作用下工作易出现开裂问题。以某步进式加热炉炉底平移框架梁体开裂治理项目为例,通过现场调查、验算分析,从结构受力角度出发对其开裂原... 步进式加热炉作为一种加热设备在金属加工行业广泛应用,步进梁作为其机械传动部件,在长期往复循环作用下工作易出现开裂问题。以某步进式加热炉炉底平移框架梁体开裂治理项目为例,通过现场调查、验算分析,从结构受力角度出发对其开裂原因进行深入分析。结果表明,该加热炉炉底平移框架梁体在长期往复循环载荷作用下由于疲劳导致了开裂,滚轮出现脱空加剧了疲劳开裂的速度,同时,滚轮出现偏心使梁体腹板支承加劲肋底部产生屈曲变形。最后,从开裂原因出发对梁体出具加固方案,能使其满足下一个炉龄的使用要求,加固方案合理可行。 展开更多
关键词 步进式加热炉 步进梁 平移框架 开裂 加固方案
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Transfer Path Contribution to Floor Vibration of Metro Vehicles Based on Operational Transfer Path Analysis Method 被引量:1
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作者 Laixian Peng Jian Han +2 位作者 Jiaxing Nie Xinbiao Xiao Caiying Mi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第2期228-238,共11页
Operational transfer path analysis(OTPA)is an advanced vibration and noise transfer path identification and contribution evaluation method.However,the application of OTPA to rail transit vehicles considers only the ex... Operational transfer path analysis(OTPA)is an advanced vibration and noise transfer path identification and contribution evaluation method.However,the application of OTPA to rail transit vehicles considers only the excitation amplitude and ignores the influence of the excitation phase.This study considers the influence of the excitation amplitude and phase,and analyzes the contribution of the secondary suspension path to the floor vibration when the metro vehicle runs at 60 km/h,using an analysis based on the OTPA method.The results show that the vertical direction of the anti-rolling torsion bar area provides the maximum contribution to the floor vibration,with a contribution of 22.1%,followed by the longitudinal vibration of the air spring area,with a contribution of 17.1%.Based on the contribution analysis,a transfer path optimization scheme is proposed,which may provide a reference for the optimization of the transfer path of metro vehicles in the future. 展开更多
关键词 OTPA Secondary suspension Contribution analysis transfer path optimization scheme Metro vehicles
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Systematic Direct Approach for Optimizing Continuous-thrust Earth-orbit Transfers 被引量:5
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作者 高扬 李卫琪 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第1期56-69,共14页
This article presents a systematic direct approach to carry out effective optimization of a wide range of continuous-thrust Earth-orbit transfers with intermediate-level thrust acceleration,including minimum-time (wit... This article presents a systematic direct approach to carry out effective optimization of a wide range of continuous-thrust Earth-orbit transfers with intermediate-level thrust acceleration,including minimum-time (with a single burn arc) and mini-mum-fuel (with multiple burn arcs) transfers. With direct control parameterization,in which the control steering programs of burn arcs are interpolated through a finite number of nodes,the optimal control problem is converted into the parameter optimi-zation proble... 展开更多
关键词 LOW-THRUST orbital transfer optimization multiple shooting variable specific impulse guidance scheme model pre-dictive control
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A multi-objective decision-making method for the treatment scheme of landslide hazard 被引量:8
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作者 QuanminXie YuanyouXia 《Journal of University of Science and Technology Beijing》 CSCD 2004年第2期101-105,共5页
The treatment engineering of landslide hazard is a complicated systemengineering. The selecting treatment scheme is influenced by many factors such as technology,economics, environment, and risk. The decision-making o... The treatment engineering of landslide hazard is a complicated systemengineering. The selecting treatment scheme is influenced by many factors such as technology,economics, environment, and risk. The decision-making of treatment schemes of landslide hazard is aproblem of comprehensive judgment with multi-hierarchy and multi-objective. The traditional analysishierarchy process needs identity test. The traditional analysis hierarchy process is improved bymeans of optimal transfer matrix here. An improved hierarchy decision-making model for the treatmentof landslide hazard is set up. The judgment matrix obtained by the method can naturally meet therequirement of identity, so the identity test is not necessary. At last, the method is applied tothe treatment decision-making of the dangerous rock mass at the Slate Mountain, and its applicationis discussed in detail. 展开更多
关键词 landslide hazard treatment scheme improved hierarchy decision-making model optimal transfer matrix
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Prediction of Better Flow Control Parameters in MHD Flows Using a High Accuracy Finite Difference Scheme
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作者 A. D. Abin Rejeesh S. Udhayakumar +1 位作者 T. V. S. Sekhar R. Sivakumar 《American Journal of Computational Mathematics》 2017年第3期243-275,共33页
We have successfully attempted to solve the equations of full-MHD model within the framework of &Psi;- &omega;formulation with an objective to evaluate the performance of a new higher order scheme to predict b... We have successfully attempted to solve the equations of full-MHD model within the framework of &Psi;- &omega;formulation with an objective to evaluate the performance of a new higher order scheme to predict better values of control parameters of the flow. In particular for MHD flows, magnetic field and electrical conductivity are the control parameters. In this work, the results from our efficient high order accurate scheme are compared with the results of second order method and significant discrepancies are noted in separation length, drag coefficient and mean Nusselt number. The governing Navier-Stokes equation is fully nonlinear due to its coupling with Maxwell’s equations. The momentum equation has several highly nonlinear body-force terms due to full-MHD model in cylindrical polar system. Our high accuracy results predict that a relatively lower magnetic field is sufficient to achieve full suppression of boundary layer and this is a favorable result for practical applications. The present computational scheme predicts that a drag-coefficient minimum can be achieved when &beta;=0.4 which is much lower when compared to the value &beta;=1 as given by second order method. For a special value of &beta;=0.65, it is found that the heat transfer rate is independent of electrical conductivity of the fluid. From the numerical values of physical quantities, we establish that the order of accuracy of the computed numerical results is fourth order accurate by using the method of divided differences. 展开更多
关键词 Full-MHD Equations FORCED CONVECTIVE Heat transfer High Order Compact schemes Divided DIFFERENCES
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Price Analysis of Water Supply for South-to-North Water Transfer Project
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作者 QIU Zhong enProfessor, Design Institute, Changjiang Water Resources Commission, Wuhan 430010, China Tan Chang liSenior Engineer, Design Institute, Changjiang Water Resources Commission, Wuhan 430010, China ZHU Qin Engineer, Design Institute, Chan 《人民长江》 北大核心 2001年第S1期29-32,共4页
The factors influencing the water supply price of a hydraulic project include natural conditions and economic policies. This paper thoroughly demonstrates the water price of South-to-North Water Transfer Project from ... The factors influencing the water supply price of a hydraulic project include natural conditions and economic policies. This paper thoroughly demonstrates the water price of South-to-North Water Transfer Project from the viewpoint of economic policies. It is considered that if the project is assigned as a profitable one and built depending on commercial loan from bank completely or mostly, the water price will be too high to be undertaken by users,and if the project places the public good at first while considering the economic benefit, its investment mainly relies on the state (national or local governments) appropriation and self-raised funds and a little from the bank loan on favorable terms, the price determined according to the principle of satisfying the cost and reasonable profit will be relatively lower and can be undertaken by the users in the North China where water shortage is serious. The problem of higher water price of agricultural irrigation to the north of the Yellow River can be tackled by taking measures such as "compensating agriculture by industry" according to foreign practical experiences and relevant suggestions. 展开更多
关键词 PRICE of WATER supply WATER PRICE estimation FUND RAISING schemes WATER transfer cost Middle-Route Project of South-to-North WATER transfer
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碳排放权交易、成本转嫁与绿色技术创新——来自民航业的证据 被引量:1
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作者 田利军 许倩 王俊凯 《物流科技》 2025年第1期95-100,共6页
碳排放权交易是控制和减少温室气体排放、推动绿色低碳发展的重大制度创新。以中国商业航空公司为研究对象,以2013—2021年为时间窗口,采用DID模型检验了碳市场交易机制对绿色技术创新的影响及成本转嫁能力的对该影响的调节效应。研究发... 碳排放权交易是控制和减少温室气体排放、推动绿色低碳发展的重大制度创新。以中国商业航空公司为研究对象,以2013—2021年为时间窗口,采用DID模型检验了碳市场交易机制对绿色技术创新的影响及成本转嫁能力的对该影响的调节效应。研究发现,参与碳市场的控排企业基于成本压力、声誉效应和潜在收益会强化绿色技术创新。碳交易机制的政策效应存在显著滞后性,长周期观察更能体现政策效果。成本转嫁能力负向调节碳交易机制对绿色技术创新的促进作用,碳排放权交易政策对控排企业绿色技术创新的促进作用存在产权异质性、规制强度异质性、配额分配方式异质性、企业规模异质性和经营模式的异质性。研究结论为合理评估碳排放权交易的政策效应,纠偏民航企业绿色行为异化,促进行业高质量发展提供理论依据和经验证据。 展开更多
关键词 碳排放权交易 成本转嫁 绿色技术创新 民航业
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轨道交通换乘枢纽客流组织方案仿真评价 被引量:2
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作者 吕慎 林均沛 张达奇 《交通科技与经济》 2025年第1期74-81,共8页
为缓解大客流换乘枢纽站台拥堵,研究枢纽内客流组织方案有效评估方法,以提升乘客的换乘效率和安全。选取线路满载率高且客流量大的换乘枢纽为研究对象,以深圳上梅林轨道交通枢纽为例,针对站台拥堵问题提出经通道绕行站厅至站台换乘的客... 为缓解大客流换乘枢纽站台拥堵,研究枢纽内客流组织方案有效评估方法,以提升乘客的换乘效率和安全。选取线路满载率高且客流量大的换乘枢纽为研究对象,以深圳上梅林轨道交通枢纽为例,针对站台拥堵问题提出经通道绕行站厅至站台换乘的客流组织方案。分析乘客对节点设施的选择决策行为,应用Logit模型建立枢纽内关键节点设施选择模型,确定乘客对楼梯、扶梯和垂直电梯的选择概率,设定仿真平台行人行为模块。将Fruin设施服务水平划分标准和乘客平均换乘时间作为乘客安全和效率评估依据,基于MassMotion对该客流组织方案有效性进行评估。结果表明:该客流组织方案不仅将站台拥挤最严重区域的服务水平由E级提升为C级,而且线路满载率大的方向平均换乘时间减少6.65%。 展开更多
关键词 交通工程 客流组织方案 仿真评价 换乘枢纽 轨道交通
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生态环境修复方案的模糊-改进AHP评价——以盘石头水库为例
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作者 李建林 胡兴文 +3 位作者 张钰锋 邓晓颖 齐玉峰 郝成元 《河南理工大学学报(自然科学版)》 北大核心 2025年第4期134-141,共8页
生态环境修复方案的可行性论证与修复效果评价是生态环境修复工程的重要内容,对生态环境修复工程的设计及建设具有重要指导意义。目的为确定生态环境修复方案可行性和修复的综合效果,以盘石头水库为例,对该水库生态修复方案进行综合评... 生态环境修复方案的可行性论证与修复效果评价是生态环境修复工程的重要内容,对生态环境修复工程的设计及建设具有重要指导意义。目的为确定生态环境修复方案可行性和修复的综合效果,以盘石头水库为例,对该水库生态修复方案进行综合评价研究。方法首先,参照OECD(Organization for Economic Cooperation and Development)模型,构建由生态效益、景观效益、社会效益、维护管理共4个准则层和18个评价子指标组成的盘石头水库生态环境修复方案可行性和修复效果评价体系;其次,通过最优传递矩阵对层次分析法的权重计算进行改进,对构建的评价指标体系进行权重的计算;最后,将改进AHP与模糊综合评价方法相结合,对盘石头水库生态修复方案进行综合评价。结果结果表明,在盘石头水库生态环境修复方案中最重要的准则层指标是生态效益;在选取的18个评价子指标中,物种多样性、观赏价值、改善城市形象和降低灾害这4个指标的权重较大;所评价的鹤壁市盘石头水库生态环境修复方案的修复效果为优,方案可行。结论模糊-改进AHP法为生态环境修复及其方案可行性的评价提供了一种新的、更有效的方法。 展开更多
关键词 盘石头水库 生态环境修复方案 最优传递矩阵 改进层次分析法 模糊综合评价
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Investigation of nonlinear temperature distribution in biological tissues by using bioheat transfer equation of Pennes’ type 被引量:3
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作者 Ahmed Lakhssassi Emmanuel Kengne Hicham Semmaoui 《Natural Science》 2010年第3期131-138,共8页
In this paper, a two level finite difference scheme of Crank-Nicholson type is constructed and used to numerically investigate nonlinear temperature distribution in biological tissues described by bioheat transfer equ... In this paper, a two level finite difference scheme of Crank-Nicholson type is constructed and used to numerically investigate nonlinear temperature distribution in biological tissues described by bioheat transfer equation of Pennes’ type. For the equation under consideration, the thermal conductivity is either depth-dependent or tem-perature-dependent, while blood perfusion is temperature-dependent. In both cases of depth- dependent and temperature-dependent thermal conductivity, it is shown that blood perfusion decreases the temperature of the living tissue. Our numerical simulations show that neither the localization nor the magnitude of peak tempera-ture is affected by surface temperature;however, the width of peak temperature increases with surface temperature. 展开更多
关键词 Bioheat transfer EQUATION of Pennes TYPE Pennes’ Bioheat transfer EQUATION Modified Crank-Nicholson Method TWO-LEVEL FINITE DIFFERENCE scheme
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Modeling of unsteady MHD free convection flow with radiative heat transfer in a rotating fluid
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作者 Harouna Naroua 《Natural Science》 2010年第12期1386-1393,共8页
In this paper, a numerical simulation has been carried out on unsteady hydromagnetic free convection near a moving infinite flat plate in a rotating medium. The temperatures involved are assumed to be very high so tha... In this paper, a numerical simulation has been carried out on unsteady hydromagnetic free convection near a moving infinite flat plate in a rotating medium. The temperatures involved are assumed to be very high so that the radiative heat transfer is significant, which renders the problem highly non-linear even with the assumption of a differential approximation for the radiative heat flux. A numerical method based on the Nakamura scheme has been employed to obtain the temperature and velocity distributions which are depicted graphically. The effects of the different parameters entering into the problem have been discussed extensively. 展开更多
关键词 Modeling Numerical Simulation Nakamura scheme UNSTEADY HYDROMAGNETIC Free CONVECTION RADIATIVE Heat transfer COMPUTER Program
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基于线性优化模型的口门引水流量优化研究 被引量:1
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作者 屈磊飞 代小平 +4 位作者 刘闯 马建强 沈超 金倩 陈胜丽 《华北水利水电大学学报(自然科学版)》 北大核心 2025年第3期61-68,共8页
引入清水是改善河道水质的重要措施,在多引水口门与流量限制条件下,科学确定各口门的引水流量是提高引水效率的关键。在分析引水对河道水质改善方式的基础上,建立了河道引水水质方程,进而以水质改善率最大为目标,以引水流量、引水量、... 引入清水是改善河道水质的重要措施,在多引水口门与流量限制条件下,科学确定各口门的引水流量是提高引水效率的关键。在分析引水对河道水质改善方式的基础上,建立了河道引水水质方程,进而以水质改善率最大为目标,以引水流量、引水量、河道引水后水质为约束条件,构建了河道引水流量线性优化模型,并以望虞河常熟段东岸口门为例,基于典型区域的调水试验,验证了引水水质方程的有效性,同时对口门的引水流量进行了优化模拟。结果表明:引水水质方程的预测水质与实测水质的平均相关系数为0.40,最高相关系数为0.66,该方程能够较好地预测离引水口门较近河道的水质;优化模型能够在满足约束条件下实现优化目标,模拟得到的河道平均水质改善率为55%。鉴于引水口门基本不具备停水条件,建议各口门采取持续小流量引水方式。该研究内容为一般精度下的河道引水水质分析和引水流量优化提供了一种简便方法,所得结论可为引清调度实践提供参考。 展开更多
关键词 引清调度 调水方案 望虞河 线性规划模型
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不同调水方式对调水河流水文情势影响评估 被引量:1
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作者 张钰 崔萌 +6 位作者 唐梅英 严登明 刘杨 张权 盖永岗 虎珀 王珈珞 《南水北调与水利科技(中英文)》 北大核心 2025年第3期651-659,共9页
为定量评估不同调水方式对调水河流水文情势的影响,根据减水比与丰增枯减等原则设置7种调水方式,采用水文变异指标法和改进变化范围法,对不同调水方式下南水北调西线一期上线6座水源水库下游水文情势变异程度进行分析。结果表明:基于推... 为定量评估不同调水方式对调水河流水文情势的影响,根据减水比与丰增枯减等原则设置7种调水方式,采用水文变异指标法和改进变化范围法,对不同调水方式下南水北调西线一期上线6座水源水库下游水文情势变异程度进行分析。结果表明:基于推荐调水规模,不同调水方式明显影响输水隧洞设计流量与水源水库调节库容等工程规模指标,均匀调水方式下隧洞设计流量较小,若减水比由60%减小至40%,热巴、阿安、仁达、霍那调节库容分别增加约1.4亿、0.3亿、0.4亿、0.8亿m3,满足丰增枯减需进一步增大调节库容以提高水库丰枯调剂能力;隧洞设计流量受调水保证率影响较大,在调水保证率不变时,各水库引水支洞设计流量差别控制在1.5 m3/s;不同调水方式下各水源水库下游水文情势整体变异等级多为中等,霍那为低等;水文情势变化与减水比的大小直接相关,减水比由60%降至40%,热巴、阿安、仁达、霍那下游水文整体变异度值分别减小14.58%、12.67%、15.58%、26.92%,而丰增枯减设置对水文情势改变视水库而定。 展开更多
关键词 南水北调西线 水源区 不同调水方式 丰增枯减 减水比 水文情势影响评估
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