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Associations of land use around rail transit stations with jobs-housing distribution of rail commuters from smart-card data 被引量:1
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作者 Qingming Zhan Yuqiu Jia +2 位作者 Zhenhua Zheng Qi Zhang Lei Luo 《Geo-Spatial Information Science》 SCIE EI CSCD 2023年第3期346-361,共16页
Previous studies generally used land use and travel flow to investigate the efficiency of the railway system in Transit-Oriented Development(TOD)cities.Furthermore,to study the association of land use and jobs-housing... Previous studies generally used land use and travel flow to investigate the efficiency of the railway system in Transit-Oriented Development(TOD)cities.Furthermore,to study the association of land use and jobs-housing distribution of commuters,we can find out the potential development of rail commuting.In this research,four railway lines in Wuhan,China,were selected to explore the land use in promoting practical commuting population according to the smart-card data obtained.For land use issues,except the road density and building density,a Normalized Location-Weighted Landscape Index(NLWLI)based on the source-sink theory in landscape ecology was established to assess the jobs-housing land use around rail transit stations.Meanwhile,employment and housing details of commuters around rail transit stations were identified using smart-card data.We found that the generation of commuting flow was affected by building density and the land use of employment in the immediate vicinity of rail transit stations.The distribution of building density and commuters in a mature rail line was roughly a normal distribution.However,due to the inconsistency of land use and jobs-housing distribution around stations,the requirement of the balance of land use and jobs-housing distribution should be reduced at the scale of rail stations in the TOD planning systems.This study is the application of massive smart-card data in the field of urban research.It identifies land use issues that affect rail transit commuting flow,and can help urban planners improve the efficiency of rail transit through planning and design. 展开更多
关键词 commuter jobs-housing ratio source-sink landscape TOD
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Prediction of Commuter Vehicle Demand Torque Based on Historical Speed Information
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作者 Shiji Sun Mingxin Kang Yuzhe Li 《Journal of Beijing Institute of Technology》 EI CAS 2022年第4期362-370,共9页
The development of vehicle-to-everything and cloud computing has brought new opportunities and challenges to the automobile industry.In this paper,a commuter vehicle demand torque prediction method based on historical... The development of vehicle-to-everything and cloud computing has brought new opportunities and challenges to the automobile industry.In this paper,a commuter vehicle demand torque prediction method based on historical vehicle speed information is proposed,which uses machine learning to predict and analyze vehicle demand torque.Firstly,the big data of vehicle driving is collected,and the driving data is cleaned and features extracted based on road information.Then,the vehicle longitudinal driving dynamics model is established.Next,the vehicle simulation simulator is established based on the longitudinal driving dynamics model of the vehicle,and the driving torque of the vehicle is obtained.Finally,the travel is divided into several accelerationcruise-deceleration road pairs for analysis,and the vehicle demand torque is predicted by BP neural network and Gaussian process regression. 展开更多
关键词 demand torque prediction commuter vehicle historical driving data machine learning
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Analysis of GHG Emissions for City Passenger Trains: Is Electricity an Obvious Option for Montreal Commuter Trains?
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作者 Sabrina Chan Luis Miranda-Moreno Zachary Patterson 《Journal of Transportation Technologies》 2013年第2期17-29,共13页
Alternative technologies have emerged to reduce the greenhouse gas (GHG) emissions of traditional commuter rail systems powered by diesel. Even larger reductions can be obtained with energy production from renewable r... Alternative technologies have emerged to reduce the greenhouse gas (GHG) emissions of traditional commuter rail systems powered by diesel. Even larger reductions can be obtained with energy production from renewable resources. This paper uses the commuter rail system in Montreal, Quebec, as a case study for implementing alternative technologies, namely, complete electrification of the network (only one of the existing five lines is electrified) and hydrogen fuel cell-powered trains. It is important to note that the main source of electricity generation in Quebec is hydropower which is offered at a relatively low cost. Several criteria were considered to determine the most suitable alternative including GHG emissions from operation and fuel production, operation and capital costs, and technological and commercial viability. Electrification of the commuter rail system would decrease annual emissions by 98% which is more than 27,000 tons. The GHG reductions for hydrogen trains are lower than electric trains but still substantial. The operation costs favor the electrification scenario;however, the high costs of electrical infrastructure make hydrogen trains more competitive since additional infrastructure is unnecessary. However, hydrogen trains remain a new and unproven technology;uncertainties associated with it should be settled before full implementation. 展开更多
关键词 Alternative Technologies commuter RAIL GREENHOUSE GASES
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First Aid Kit Uses among Commuter Bus Attendants in Nyamagana District, Mwanza City
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作者 Namanya Basinda Giveness Zacharia +2 位作者 Joshua Patrick Ngimbwa Joshua Patrick Ngimbwa Stanley Mwita 《Open Journal of Epidemiology》 2022年第3期274-284,共11页
Introduction: Provision of prehospital care in the event of a crash is vital to prevent loss of life and other severe outcomes. However, this involves adequate first aid knowledge and skills among vehicle attendants, ... Introduction: Provision of prehospital care in the event of a crash is vital to prevent loss of life and other severe outcomes. However, this involves adequate first aid knowledge and skills among vehicle attendants, and most importantly, the availability of the first aid kit items and knowing their uses. The aim of this study was to determine the knowledge, availability, and use of first aid kits among commuter bus attendants. Methods: This cross-sectional study was conducted in Nyamagana district, Mwanza, Tanzania in May 2018. A total of 240 were recruited randomly and interviewed using pretested questionnaires. Data was first entered in Microsoft Excel for data cleaning and consistent checks and thereafter exported to the software STATA for analysis. Results: Findings from the study showed that 22.9% of respondents had knowledge concerning first aid practice. Only 17.9% of the participants claimed to have ever had first aid training. All commuters had incompletely equipped first aid kits. Around 30.8% of the respondents reported having practiced giving first aid. Conclusion: The majority of commuter bus attendants were found to have insufficient knowledge of first aid and first aid kits, according to the current study. No vehicle had a complete kit despite the fact that the majority of the participants believed that having a first aid kit in the vehicle was essential. The majority of participants expressed a desire to assist and learn, indicating that efforts to train commuter attendants should be undertaken and potentially save lives. 展开更多
关键词 First Aid Kit First Aid Prehospital Care commuter Buses Mwanza
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Analysis of Benzene Exposure Levels on Commuters Traveling within the Metropolitan Area of Costa Rica
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作者 Wendy Villalobos-Gonzalez Germain Esquivel-Hernandez +2 位作者 Ricardo Sanchez-Murillo José Leonardo Corrales-Salazar Juan Valdes-Gonzalez 《Open Journal of Air Pollution》 2015年第1期38-46,共9页
This study reports the benzene exposure levels of commuters traveling within the metropolitan area of Costa Rica using personal cars, buses, and urban trains. 47 in-vehicle samples were collected in the 2014 wet seaso... This study reports the benzene exposure levels of commuters traveling within the metropolitan area of Costa Rica using personal cars, buses, and urban trains. 47 in-vehicle samples were collected in the 2014 wet season under three different driving conditions: rush hour traffic, normal traffic and weekends. Samples were collected in Tedlar bags and analyzed using 75 μm carboxenpolydimethylsiloxane (CAR/PDMS) and gas chromatography with flame ionization detection (GC-FID). Additionally, duplicate samples were collected on adsorption tubes filled with Tenax TA and analyzed by thermal desorption (TD) and GC-FID. Results indicate that travelling in cars and buses under rush hour conditions exposes commuters to statistically equal average benzene concentration of 48.7 and 51.6 μg/m3, respectively. Average benzene levels in urban trains (33.0 μg/m3) were measured only during morning rush hours. Greater benzene levels in buses than personal cars concentrations may be attributable to the immersion of traffic-related emission within the bus cabins. Factors, such as the driving pattern, the number of vehicles on the route, the road infrastructure, and the prevalence of gasoline-fueled vehicles in Costa Rica, may increase ambient benzene concentrations. Benzene levels inside car cabins reported in this study are in the range of those reported in other urban areas;however, the corresponding concentrations inside buses and urban trains (rush hour only) are higher than previously published exposure levels. 展开更多
关键词 Costa Rica Benzene EXPOSURE LEVELS Solid Phase MICROEXTRACTION (SPME) Traffic Hours commuterS EXPOSURE
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An Analysis of the Women Commuters’ Satisfaction in the Public Bus Service in Bangladesh: A Survey on Local Buses in Major Cities
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作者 Ayesha Umme Kojima Aya Kubota Hisashi 《Journal of Transportation Technologies》 2022年第4期559-577,共19页
Bangladesh is one of the most populated developing countries where public bus service plays a vital role as a public transport mode since it is easily available and cost-effective. In the social, commercial, education... Bangladesh is one of the most populated developing countries where public bus service plays a vital role as a public transport mode since it is easily available and cost-effective. In the social, commercial, educational, and administrative spheres, women’s participation in the labor force in economic enterprises is steadily expanding in the country. Very little research considers only women commuters to analyze the service quality of public buses and they selected only Dhaka city as a study area. However, a large number of trips were generated by women commuters in the industrial and commercial zones such as Gazipur, Narayanganj, and Dhaka. This paper ascertains the public bus service attributes that affect women commuters’ satisfaction as well as finds out the major problems of women commuters while traveling on public buses and the possible solutions to them. This survey included 766 women commuters from Dhaka, Narayanganj, and Gazipur who were interviewed face to face. Structural Equation Model (SEM) was used as the instrument for identifying the service quality (SQ) attributes that influenced the women commuters’ satisfaction. A series of models were developed based on the trial-and-error method and the model M<sub>3</sub> is selected as the best fit according to SEM fit indices values. The study’s main goal was to compile a list of service quality attributes that influence women commuters’ satisfaction. Major issues with the current public bus service in terms of safety and security, as well as remedies, were identified through discussions with experienced female commuters. These findings reveal that women commuters’ satisfaction is primarily influenced by safety and security, as well as the degree of comfort provided by bus service because they frequently encounter major safety and security issues on public buses and want an immediate remedy. This paper offers some potential strategies for addressing the issues, which may prompt policymakers to pay more attention to these aspects in transportation planning. 展开更多
关键词 Public Bus Service Quality Women commuters’ Satisfaction SEM
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Recouping Braking Energy from Diesel-Hauled Commuter Trains
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作者 Peter Eggleton 《Journal of Energy and Power Engineering》 2013年第10期1871-1883,共13页
Research was undertaken to define the concept of a coach-based braking energy recoupment, storage and regeneration system to augment the acceleration of regional commuter trains hauled by diesel locomotives. Functiona... Research was undertaken to define the concept of a coach-based braking energy recoupment, storage and regeneration system to augment the acceleration of regional commuter trains hauled by diesel locomotives. Functional specifications were developed having the goal of increasing by 25% the acceleration rate of a train consisting of 10 bi-level coaches hauled by a 3,000 hp diesel locomotive, typical of the rolling stock now in commuter services in Canada and the USA. Examining three alternate hybrid system technologies for train retardation based, respectively, on hydrostatic, battery and ultracapacitor energy storage. The ultracapacitor hybrid system appeared the most promising due to the capability ofultracapacitors to repeatedly and rapidly accept large energy charges without degradation, temperature insensitive and flexible in the placement of modules in the limited space available. Analyses of train operation simulations showed that in addition to augmenting acceleration and reducing trip time, braking energy recoupment reduced fuel consumption and concomitant diesel emissions. 展开更多
关键词 commuter trains braking energy recoupment STORAGE REGENERATION ultracapacitors.
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Commuter exposure to BTEX in public transportation modes in Bangkok, Thailand
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作者 Maneerat Ongwandee Orathai Chavalparit 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第3期397-404,共8页
Measurements and monitoring of volatile organic compounds (VOCs) have been conducted in the metropolitan Bangkok. However, in-vehicle levels of VOCs are still lacking. This study investigated VOCs concentrations in ... Measurements and monitoring of volatile organic compounds (VOCs) have been conducted in the metropolitan Bangkok. However, in-vehicle levels of VOCs are still lacking. This study investigated VOCs concentrations in four public transportation modes in Bangkok, Thailand during two rush hour periods (7:00–9:00 a.m. and 4:00–7:00 p.m.). The four modes included an air-conditioned bus (A/C bus), non-air-conditioned bus (non-A/C bus), electric sky train, and a passenger boat traveling along the canal. Comparison among three important bus routes was also studied. In-vehicle air samples were collected using charcoal sorbent tubes and then analyzed by a gas chromatography-mass spectrometer. Results showed that the transportation modes significantly influenced the abundance of in-vehicle benzene, toluene, ethylbenzene, and m,p-xylene (BTEX). Median concentrations of BTEX were 11.7, 103, 11.7, and 42.8 μg/m3 in A/C bus; 37.1, 174, 14.7, and 55.4 μg/m3 in non-A/C bus; 2.0, 36.9, 0.5, and 0.5 μg/m3 in sky train; and 3.1, 58.5, 0.5, and 6.2 μg/m3 in boat, respectively. Wilcoxon rank sum test indicated that toluene and m,p-xylene in the sky trains were statistically lower than that in the other three modes at a p-value of 0.05. There were statistical differences in TEX concentrations among the bus routes in the non-A/C buses. In addition, the benzene to toluene ratios implied that tail-pipe emissions were important contributor to the abundance of in-vehicle VOCs. 展开更多
关键词 BENZENE public transportation COMMUTING vehicle exhaust
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Choice behavior of commuters’rail transit mode during the COVID-19 pandemic based on logistic model 被引量:11
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作者 Limin Tan Changxi Ma 《Journal of Traffic and Transportation Engineering(English Edition)》 CSCD 2021年第2期186-195,共10页
To understand whether commuters will take rail transit during the COVID-19 pandemic,a logistic regression model was constructed from three aspects of personal attributes,travel attributes and perception of COVID-19 ba... To understand whether commuters will take rail transit during the COVID-19 pandemic,a logistic regression model was constructed from three aspects of personal attributes,travel attributes and perception of COVID-19 based on 559 valid questionnaires.The results show that:occupation,commuting tools before the COVID-19 pandemic,walking time from residence to the nearest subway station,the possibility of being infected in private car and the possibility of being infected in public transport have significant influence on the commuters’choice of rail transit.Self-employed people and freelancers,commuters who used non-public transport before the COVID-19 pandemic,and commuters who take longer to walk from their residences to the nearest subway station are less likely to commute by rail transit during the COVID-19 pandemic.Commuters who think that the risk of being infected with the virus in public transport is higher have a lower probability of choosing rail transit.The confidence in bus/subway/taxi/taxi-hailing of commuters who do not choose to commute by rail transit during the COVID-19 pandemic is not high.The study of this paper can provide reference for the formulation of urban rail transit control measures during the COVID-19 pandemic,so as to formulate more perfect measures to ensure the safety of the returning workers. 展开更多
关键词 Traffic engineering commuterS Rail transit QUESTIONNAIRE Influencing factors Logistic regression model
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功能至尚 自在骑行——Levi’s~ Commuter系列,单车潮人必选潮品
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《东方电影》 2012年第8期58-59,共2页
近几年,环保健康的概念已越来越受年轻人的关注,众多年轻人选择了骑单车出行,这种最普及简单的出行工具已成为最潮的街头运动。单车运动一时间如同飓风一般席卷而来!怎样才能在骑行中仍旧保持最IN的造型。想必是热衷单车且对时尚敏感的... 近几年,环保健康的概念已越来越受年轻人的关注,众多年轻人选择了骑单车出行,这种最普及简单的出行工具已成为最潮的街头运动。单车运动一时间如同飓风一般席卷而来!怎样才能在骑行中仍旧保持最IN的造型。想必是热衷单车且对时尚敏感的潮人们最关心的问题了。如今Levi’s<sup>?</sup>透过聆听潮流单车族的心声,触发灵感,推出了一款适合走在潮流前端的单车族的产品,全新的Commuter系列,为风中的骑手量身打造,时尚和运动终于可以并户同行了! 展开更多
关键词 commuter Levi’s 潮人 车族 出行工具 专业功能 环保健康 环保日 行中 在黑暗中
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功能至尚 自在骑行——Levi’s~ Commuter系列,单车潮人必选潮品
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《东方电影》 2012年第7期78-79,共2页
近几年,环保健康的概念已越来越受年轻人的关注,众多年轻人选择了骑单车出行,这种最普及简单的出行工具已成为最潮的街头运动。单车运动一时间如同飓风一般席卷而来!怎样才能在骑行中仍旧保持最IN的造型。想必是热衷单车且对时尚敏感的... 近几年,环保健康的概念已越来越受年轻人的关注,众多年轻人选择了骑单车出行,这种最普及简单的出行工具已成为最潮的街头运动。单车运动一时间如同飓风一般席卷而来!怎样才能在骑行中仍旧保持最IN的造型。想必是热衷单车且对时尚敏感的潮人们最关心的问题了。如今LeVi’s<sup>?</sup>透过聆听潮流单车族的心声,触发灵感,推出了一款适合走在潮流前端的单车族的产品,全新的Commuter系列,为风中的骑手量身打造,时尚和运动终于可以并肩同行了! 展开更多
关键词 commuter Levi’s 出行工具 潮人 车族 行中 在黑暗中 环保健康 数字统计 单声
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The New Bike Sharing A Concept for Urban Commuters
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作者 Zhao Yang 《Voice of Friendship》 2017年第2期25-27,共3页
Shanghai saw the launch last April of bike-sharing startup MoBike,with its fleet of station-free bicycles distinguished by their app-activated rear-wheel locks.The company’s aim was to provide urban dwellers with aff... Shanghai saw the launch last April of bike-sharing startup MoBike,with its fleet of station-free bicycles distinguished by their app-activated rear-wheel locks.The company’s aim was to provide urban dwellers with affordable,convenient,short-distance transportation.The bikes were an immediate success.A few months later they 展开更多
关键词 bus The New Bike Sharing A Concept for Urban commuters
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The Impact of Floods on the Mobility of Automobile Commuters in Shanghai Under Climate Change
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作者 Qian Yao Xinmeng Shan +1 位作者 Mengya Li Jun Wang 《International Journal of Disaster Risk Science》 CSCD 2024年第6期986-1000,共15页
As sea level rises,low-lying coastal cites face increasing threat of flood disruption,particularly in terms of human mobility.Commuters are vulnerable to bad weather,as it is difficult to cancel trips even in extreme ... As sea level rises,low-lying coastal cites face increasing threat of flood disruption,particularly in terms of human mobility.Commuters are vulnerable to bad weather,as it is difficult to cancel trips even in extreme weather conditions.Using Shanghai's automobile commuting population as an example,we categorized commuters by travel distance and income level to assess disruptions and delays due to floods,considering future sea level rise.The results show that local flooding disrupts commuting patterns by affecting roadways,with disruption decreasing with distance from the flooded area.This offers a mobility perspective on the indirect impacts of floods.During baseline flood events,long-distance commuters and the lowincome group are most affected,while short-distance commuters and the high-income group are less impacted.As sea level rises,floods will threaten all commuting groups,especially the high-income group.Using inaccessibility-commuting delay bivariate maps,this study revealed how socioeconomic differences impact mobility recovery after floods under climate change.The research highlights the differential impacts of floods on various socioeconomic groups in the context of climate change,offering insights for future urban planning and disaster mitigation strategies. 展开更多
关键词 Climate change Commuting patterns Human mobility Indirect flood effect SHANGHAI Socioeconomic disparities
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A Bilinear Sparse Domination for the Maximal Calder´on Commutator with Rough Kernel
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作者 WANG Meizhong ZHAO Junyan 《数学进展》 北大核心 2025年第5期1059-1074,共16页
LetΩbe homogeneous of degree zero,integrable on S^(d−1) and have vanishing moment of order one,a be a function on R^(d) such that ∇a∈L^(∞)(R^(d)).Let T*_(Ω,a) be the maximaloperator associated with the d-dimensional... LetΩbe homogeneous of degree zero,integrable on S^(d−1) and have vanishing moment of order one,a be a function on R^(d) such that ∇a∈L^(∞)(R^(d)).Let T*_(Ω,a) be the maximaloperator associated with the d-dimensional Calder´on commutator defined by T*_(Ωa)f(x):=sup_(ε>0)|∫_(|x-y|>ε)^Ω(x-y)/|x-y|^(d+1)(a(x)-a(y))f(y)dy.In this paper,the authors establish bilinear sparse domination for T*_(Ω,a) under the assumption Ω∈L∞(Sd−1).As applications,some quantitative weighted bounds for T*_(Ω,a) are obtained. 展开更多
关键词 Calderon commutator Fourier transform multiplier operator approximation bilinear sparse domination rough kernel
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Boundedness of the Commutators of Rough Singular Integral Operators on Triebel–Lizorkin Spaces
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作者 LIU Jie GAO Wenhua 《数学进展》 北大核心 2025年第5期1075-1086,共12页
Let Ω be homogeneous of degree zero,integrable on S^(n−1) and have mean value zero,T_(Ω) be the homogeneous singular integral operator with kernel Ω(x)/|x|^(n) and[b,T_(Ω)]be the commutator of T_(Ω)with symbol b∈BMO(... Let Ω be homogeneous of degree zero,integrable on S^(n−1) and have mean value zero,T_(Ω) be the homogeneous singular integral operator with kernel Ω(x)/|x|^(n) and[b,T_(Ω)]be the commutator of T_(Ω)with symbol b∈BMO(R^(n)).In this paper,the authors prove that if sup ζ∈S^(n−1)∫Sn−1^(|Ω(θ)|log^(β)(1/|θ·ζ|)dθ<∞ with β>2,then[b,T_(Ω)]is bounded on Triebel–Lizorkin space F^(0,q)p(R^(n))provided that 1+1/β−1<p,q<β. 展开更多
关键词 rough singular integral operator COMMUTATOR Triebel-Lizorkin space Littlewood-Paley theory
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Compactness of Fractional Calderón Type Commutators on Morrey Spaces
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作者 LI Aobo MEI Ting WEI Qi 《数学进展》 北大核心 2025年第4期858-870,共13页
In this paper,the authors study the fractional Calderon type commutator T_(Ω,α)^(A)and its maximal operator M_(Ω,α)^(A)with kernels having some kinds of Log-type Dini-condition and obtain the compactness on Morrey... In this paper,the authors study the fractional Calderon type commutator T_(Ω,α)^(A)and its maximal operator M_(Ω,α)^(A)with kernels having some kinds of Log-type Dini-condition and obtain the compactness on Morrey spaces L^(p,λ)(R^(n)). 展开更多
关键词 Calderón type commutator COMPACTNESS Log-type Dini-condition Morrey space
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Phragmen-Lindelof Alternative Results for the Linear Viscoelastic Damped Wave Equation
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作者 SHI Jincheng LIU Yan LIN Yiwu 《应用数学》 北大核心 2025年第2期508-516,共9页
In this article,the viscoelastic damped was equation in three-dimensional cylindrical domain were studied by using a second-order differential inequality.We proved a Phragm´en-Lindelof alternative results,i.e.,th... In this article,the viscoelastic damped was equation in three-dimensional cylindrical domain were studied by using a second-order differential inequality.We proved a Phragm´en-Lindelof alternative results,i.e.,the smooth solutions either grow or decay exponentially as the distance from the entry section tends to infinity.Our results can be seen as a version of the Saint-Venant principle. 展开更多
关键词 Fractional integral commutators Variable exponent Herz-Hardy space Variable exponent weak Herz space Variable kernel
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Impact of Short-Term Power Shortage from Low Voltage Ride through and DC Commutation Failure on Power Grid Frequency Stability
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作者 Wenjia Zhang Sixuan Xu +2 位作者 Wanchun Qi Zhuyi Peng Wentao Sun 《Energy Engineering》 2025年第6期2371-2387,共17页
Countries worldwide are advocating for energy transition initiatives to promote the construction of low-carbon energy systems.The low voltage ride through(LVRT)characteristics of renewable energy units and commutation... Countries worldwide are advocating for energy transition initiatives to promote the construction of low-carbon energy systems.The low voltage ride through(LVRT)characteristics of renewable energy units and commutation failures in line commutated converter high voltage direct current(LCC-HVDC)systems at the receiving end leads to short-term power shortage(STPS),which differs from traditional frequency stability issues.STPS occurs during the generator’s power angle swing phase,before the governor responds,and is on a timescale that is not related to primary frequency regulation.This paper addresses these challenges by examining the impact of LVRT on voltage stability,developing a frequency response model to analyze the mechanism of frequency instability caused by STPS,deriving the impact of STPS on the maximum frequency deviation,and introducing an energy deficiency factor to assess its impact on regional frequency stability.The East China Power Grid is used as a case study,where the energy deficiency factor is calculated to validate the proposed mechanism.STPS is mainly compensated by the rotor kinetic energy of the generators in this region,with minimal impact on other regions.It is concluded that the energy deficiency factor provides an effective explanation for the spatial distribution of the impact of STPS on system frequency. 展开更多
关键词 Commutation failure frequency stability LVRT renewable energy short-term power shortage LCCHVDC
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Riding on Four Lanes How a 10-km road expansion project will transform lives in Rwanda’s Masaka and beyond
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作者 《ChinAfrica》 2025年第11期42-43,共2页
For the people of Masaka,Kabuga and Muyumbu in Rwanda,the daily commute often takes longer than it should.A stretch of just 10 km along the Prince House-Giporoso-Masaka road can take half an hour during peak hours.The... For the people of Masaka,Kabuga and Muyumbu in Rwanda,the daily commute often takes longer than it should.A stretch of just 10 km along the Prince House-Giporoso-Masaka road can take half an hour during peak hours.The narrow two-lane artery,clogged with long-haul trucks from the Rwanda-Tanzania border and commuter traffic,has long tested the patience of drivers and pedestrians alike.In May,a long-awaited announcement finally arrived.Rwanda’s Ministry of Infrastructure confirmed plans to expand the road from two lanes to four,adding a 1.2-km flyover at Giporoso-Remera and an underpass to keep tra"c flowing smoothly.The$60.5 million(Rwf86 billion)project will be fully funded by China,a testament to the deepening friendship and cooperation between the two nations.For many residents,it signals the end of years of lost time and daily frustration. 展开更多
关键词 Muyumbu Rwanda Masaka traffic congestion road expansion daily commute expand road Kabuga
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L^(P) BOUNDEDNESS OF COMMUTATOR AND HÖRMANDER CONDITION
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作者 Qixiang YANG Haibo YANG +1 位作者 Chitin HON Tao QIAN 《Acta Mathematica Scientia》 2025年第5期2171-2189,共19页
For 1<p<∞,Coifman-Rochberg-Weiss established L^(p) boundedness of commutators of smooth kernels.Later,many works tried to weaken the smooth condition.In this paper,we extend these mentioned results to the case ... For 1<p<∞,Coifman-Rochberg-Weiss established L^(p) boundedness of commutators of smooth kernels.Later,many works tried to weaken the smooth condition.In this paper,we extend these mentioned results to the case of non-homogeneous but with strong H¨ormander condition.Our main skills lie in wavelet decomposition,wavelet commutators,Hardy-Littlewood maximal operator and Fefferman-Stein's vector-valued maximum function Theorem. 展开更多
关键词 WAVELETS COMMUTATOR Hardy space Hormander condition vector-valued max-imum function Lp boundedness
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