期刊文献+
共找到8篇文章
< 1 >
每页显示 20 50 100
An analysis of ridesharing trip time using advanced text mining techniques
1
作者 Wenxiang Xu Anae Sobhani +5 位作者 Ting Fu Amir Mahdi Khabooshani Aminreza Vazirinasab Sina Shokoohyar Ahmad Sobhani Behnaz Raouf 《Digital Transportation and Safety》 2023年第4期308-319,共12页
The time cost of ridesharing rental represents a crucial factor influencing users'decisions to rent a car.Researchers have explored this aspect through text analysis and questionnaires.However,the current research... The time cost of ridesharing rental represents a crucial factor influencing users'decisions to rent a car.Researchers have explored this aspect through text analysis and questionnaires.However,the current research faces limitations in terms of data quantity and analysis methods,preventing the extraction of key information.Therefore,there is a need to further optimize the level of public opinion analysis.This study aimed to investigate user perspectives concerning travel time in ridesharing,both pre and post-pandemic,within the Twitter application.Our analysis focused on a dataset from users residing in the USA and India,with considerations for demographic variables such as age and gender.To accomplish our research objectives,we employed Latent Dirichlet Allocation for topic modeling and BERT for sentiment analysis.Our findings revealed significant influences of the pandemic and the user's country of origin on sentiment.Notably,there was a discernible increase in positive sentiment among users from both countries following the pandemic,particularly among older individuals.These findings bear relevance to the ridesharing industry,offering insights that can aid in establishing benchmarks for improving travel time.Such improvements are instrumental in enabling ridesharing companies to effectively compete with other public transportation alternatives. 展开更多
关键词 Ridesharing Trip time Topic modeling Sentiment analysis Twitter data
下载PDF
Selection model of trip time for rural population 被引量:2
2
作者 冯忠祥 袁华智 +2 位作者 刘静 高璇 张卫华 《Journal of Central South University》 SCIE EI CAS 2013年第1期274-278,共5页
Referring to the 1 248 survey data of rural population in 14 provinces of China, the influencing factors of trip time choice were analyzed. Based on the basic theory of disaggregate model and its modelling method, nin... Referring to the 1 248 survey data of rural population in 14 provinces of China, the influencing factors of trip time choice were analyzed. Based on the basic theory of disaggregate model and its modelling method, nine grades were selected as the alternatives of trip time, the variables affecting time choice and the method getting their values were determined, and a multinomial logit (MNL) model was developed. Another 1 200 trip data of rural population were selected to testify the model's validity. The result shows that the maximum absolute error of each period between calculated value and statistic is 3.6%, so MNL model has high calculation accuracy. 展开更多
关键词 traffic planning rural population trip time disaggregate model multinominal logit (MNL) model
下载PDF
Synchronous hybrid transport network design 被引量:1
3
作者 李夏苗 曾明华 +1 位作者 傅白白 朱晓立 《Journal of Central South University》 SCIE EI CAS 2009年第2期332-338,共7页
Delay,as an inevitable real-world phenomenon,is usually ignored in transport network design.A model of urban hybrid transport system with stochastic delay was created on the basis of the idealized public transport sys... Delay,as an inevitable real-world phenomenon,is usually ignored in transport network design.A model of urban hybrid transport system with stochastic delay was created on the basis of the idealized public transport system design.After formulating the total trip time cost composed of accessing time in the sub-region of the city,waiting time at the public transport station,and in-vehicle time in the public transit network,the analytical properties of the total trip time cost function were investigated.The results show that in the urban hybrid transport network design,the total trip time cost reaches its approximate minimum in a δ-neighbourhood of buffer time of 1.5 min,and that through modelling optimal delay in hybrid transport system,the maximal synchronization can be achieved and operational efficiency and passenger satisfaction can be improved.The proposed modelling and analytical investigations are attempts to contribute to more realistic modelling of future idealized public transport system that involves more practical constraints. 展开更多
关键词 transport network design DELAY SYNCHRONIZATION total trip time cost
下载PDF
Transmission Delay Based Control over Networks with Wireless Links
4
作者 Zhou Zhi zhao, Han Zheng zhi College of Electronic and Information Engineering, Shanghai Jiaotong University, Shanghai 200030,China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第4期431-436,共6页
To achieve the mobility of computers during communication, the TCP connections between fixed host and mobile host may often traverse wired and wireless networks, and the recovery of losses due to wireless transmission... To achieve the mobility of computers during communication, the TCP connections between fixed host and mobile host may often traverse wired and wireless networks, and the recovery of losses due to wireless transmission error is much different from congestion control. The paper analyzes the side effect of RTT estimation while making the TCP source to handle congestion and wireless error losses properly. Then present a strategy using information feedback by the last hop acknowledgement and monitoring the queuing level of the wired bottleneck link by calculating the changes in transmission delay along the path. With the identification of the early stage of congestion, it can respond to wired congestion quickly while keeping wireless link more reliable, and make TCP react to the different packets losses more appropriately. 展开更多
关键词 Key words round trip times retransmission timeout value last hop acknowledgement delay explicit loss nodification
下载PDF
Finding an Effective Distance Between T-Cell and B-Cell Using S/W ARQ in an Immune System Communication
5
作者 Sanjit Ningthoujam Tekcham Chingkheinganba Swarnendu K Chakraborty 《China Communications》 SCIE CSCD 2020年第1期174-185,共12页
In this paper,we present the effective distance between T-cell and B-cell in an immune system using Stop and Wait(S/W)Automatic Repeat Request(ARQ).The concentration of the molecules can be increased by increasing the... In this paper,we present the effective distance between T-cell and B-cell in an immune system using Stop and Wait(S/W)Automatic Repeat Request(ARQ).The concentration of the molecules can be increased by increasing the transmitting number of molecules but it may reduce the performance of communication due to higher collision or interference with other molecules.It is also reported in the literature that the concentration of the emitted molecules reduces if the distance from Transmitter(Tx)to Receiver(Rx)increases.Thus,this paper mainly focuses on enhancing the receiver’s capture probability and higher successful complete transmission of the desired molecules by obtaining the effective distance from T-cell to B-cell.In order to find the effective distance,T-cell transmits the molecules 1(Interleukins-2)to B-cell,upon successful reception of molecules 1,antibodies(molecules 2)transmit back to T-cell.Then,the effective distance of an immune system can be obtained after T-cell detects the concentration of the molecules 2 with respect to time.Different schemes of S/W ARQ protocols have implemented in Molecular Communication(MC)but it requires retransmission of duplicate copies due to the lack of addressing an effective distance.Thus,the simulations are performed in MATLAB and the results obtain higher capture probability and also successful complete transmission of the desired molecules. 展开更多
关键词 T-CELL B-CELL MC ANTIGENS antibodies diffusion coefficient(D) round trip time(RTT)
下载PDF
Optimal charging plan for electric bus considering time-of-day electricity tariff 被引量:6
6
作者 Yuhan Liu Linhong Wang +1 位作者 Ziling Zeng Yiming Bie 《Journal of Intelligent and Connected Vehicles》 2022年第2期123-137,共15页
Purpose–The purpose of this study is to develop an optimization method for charging plans with the implementation of time-of-day(TOD)electricity tariff,to reduce electricity bill.Design/methodology/approach–Two opti... Purpose–The purpose of this study is to develop an optimization method for charging plans with the implementation of time-of-day(TOD)electricity tariff,to reduce electricity bill.Design/methodology/approach–Two optimization models for charging plans respectively with fixed and stochastic trip travel times are developed,to minimize the electricity costs of daily operation of an electric bus.The charging time is taken as the optimization variable.The TOD electricity tariff is considered,and the energy consumption model is developed based on real operation data.An optimal charging plan provides charging times at bus idle times in operation hours during the whole day(charging time is 0 if the bus is not get charged at idle time)which ensure the regular operation of every trip served by this bus.Findings–The electricity costs of the bus route can be reduced by applying the optimal charging plans.Originality/value–This paper produces a viable option for transit agencies to reduce their operation costs. 展开更多
关键词 Electric bus Charging plan time-of-day electricity tariff Stochastic trip travel time Optimization model
原文传递
A methodology for rearranging transit stops for enhancing transit users generalized travel time 被引量:1
7
作者 Mohammad Nurul Hassan Yaser E.Hawas 《Journal of Traffic and Transportation Engineering(English Edition)》 2017年第1期14-30,共17页
This study develops a methodology to consohdate transit stops. It develops a mathematical model and a program which takes stop consolidation decision(s) according to users gener- alized travel time savings and desir... This study develops a methodology to consohdate transit stops. It develops a mathematical model and a program which takes stop consolidation decision(s) according to users gener- alized travel time savings and desired accessibility. The model iterates until the users generalized travel time savings are maximized. The study tests this mathematical model in different hypothetical scenarios. Six factors (distance between stops, passenger activity, average cruising speed, maximum walking distance, service frequency, and percentage of decreased passengers) with multiple levels were set to build the scenarios. Three responses {percentage of consolidated stops, percentages of travel time and operating time savings) were observed. The findings showed that the distance between the stops the passenger ac- tivity, and the probable demand change (or the percentage of decreased passengers) are the most influential factors. The frequency of service was found to be influential as well. The average cruising speed has very little influence on the response variables. Finally, the model is tested on two routes (route 900 and 930) ofAl Ain City public bus service. It shows that 22 and 32 out of 98 and 126 stops can be consolidated in route 900 and 930 respectively. This can save considerable amounts of users travel and operating times. In monetary values, the savings are about $329,827 and $491,094 per year for routes 900 and 930, respectively. 展开更多
关键词 Public transit Stop consolidation Transit users travel time Transit operating time Trip time
原文传递
Indoor positioning based on tightly coupling of PDR and one single Wi-Fi FTM AP 被引量:3
8
作者 Yuan Wu Ruizhi Chen +3 位作者 Wenju Fu Wei Li Haitao Zhou Guangyi Guo 《Geo-Spatial Information Science》 SCIE EI CSCD 2023年第3期480-495,共16页
The indoor positioning system is now an important technique as part of the Internet-of-Things(IoT)ecosystem.Among indoor positioning techniques,multiple Wi-Fi Access Points(APs)-based positioning systems have been res... The indoor positioning system is now an important technique as part of the Internet-of-Things(IoT)ecosystem.Among indoor positioning techniques,multiple Wi-Fi Access Points(APs)-based positioning systems have been researched a lot.There is a lack of research focusing on the scene where only one Wi-Fi AP is available.This work proposes a hybrid indoor positioning system that takes advantage of the Fine-Timing Measurements(FTM)technique that is part of the IEEE 802.11mc standard,introduced back in 2016.The system uses one single Wi-Fi FTM AP and takes advantage of the built-in inertial sensors of the smartphone to estimate the device’s position.We explore both Loosely Coupled(LC)and Tightly Coupled(TC)integration schemes for the sensors’data fusion.Experimental results show that the proposed methods can achieve an average positioning accuracy of about 1 m without knowing the initial position.Compared with the LC integration method,the median error accuracy of the proposed TC fusion algorithm has improved by more than 52%and 67%,respectively,in the two experiments we set up. 展开更多
关键词 Indoor positioning Wi-Fi Fine time Measurement(FTM)/Round Trip time(RTT) Tightly Coupled(TC)integration Pedestrian Dead Reckoning(PDR) Extended Kalman Filter(EKF)
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部