scholarly journals Tandem Design of Bus Priority Based on a Pre-Signal System

2021 ◽  
Vol 13 (18) ◽  
pp. 10109
Author(s):  
Yutong Sun ◽  
Jin Li ◽  
Xiaozhong Wei ◽  
Yuling Jiao

Giving buses priority is an important measure to improve the attractiveness of public transport and to reduce urban traffic congestion. Reducing bus service delays as much as possible will have a positive impact on urban traffic. Based on the pre-signal system, a bus at an intersection with a left-turn special phase is optimized by “tandem design”. The design model is applied to the entrance of an intersection to study the process of vehicle arrival and departure at the main signal and pre-signal, and to calculate and analyze the delay changes of buses, straight social vehicles (meaning vehicles other than those required to be open to traffic) and left-turn vehicles before and after the adoption of “tandem design”. The results show that when the vehicle capacity at the intersection is saturated, the delays to buses and the delays of left-turn vehicles will be significantly reduced once the “tandem design” is adopted at the entrance of a cross intersection with a special left-turn phase. However, it has little effect on the delay of straight-on vehicles; with this system, the total delay experienced by straight vehicles will be reduced to one cycle.

2015 ◽  
Vol 740 ◽  
pp. 900-903
Author(s):  
Wen Cang Zhao ◽  
Bo Tong ◽  
Xiao Xiao Wang

Urban transport is an important part of urban activities, and it is not just a public works technical problems or traffic problems, but also is a comprehensive social problems. There are some traffic congestion problems exist in the current urban traffic network. By using the theory of generalized stochastic Petri to the study of Cyber-physical Systems (CPS), this paper established an urban transport GSPN (Generalized Stochastic Petri Net) model, which chosen bus priority strategies to improve the utilization of road.


2018 ◽  
Vol 45 (11) ◽  
pp. 986-1003 ◽  
Author(s):  
Ronghan Yao ◽  
Xiaotong Zhang ◽  
Na Wu ◽  
Xianmin Song

Unbalanced directional traffic, which often exists at intersection approaches, is an important factor to induce traffic congestion on urban streets. Considering the settings of variable approach lanes, the presence of left-turn bays, and a variety of vehicle categories on an arterial road, an optimization model that minimizes the total delay is formulated and a control method that coordinates a variable sign and the corresponding signal group is put forward. To design the signal control scenarios with time of day, the procedure for using the proposed methodology is also presented in practice. To verify the given methodology, a case study is implemented using the field data and the four scenarios. The results reveal that the new methodology can better respond to the time-varying traffic flow at intersection approaches, and the provision of variable approach lanes and left-turn bays are helpful to reduce the average delay and enhance the average speed.


Author(s):  
Duy Q. Nguyen-Phuoc ◽  
Graham Currie ◽  
Chris De Gruyter ◽  
William Young

Public transit is widely recognized to reduce urban traffic congestion, as it encourages automobile travelers off the road. However, streetcars have been criticized for causing traffic congestion because large trams must operate in mixed traffic on narrow, congested streets. At the same time, streetcars reduce congestion by encouraging automobile drivers to use trams. So what is the net effect of streetcars on congestion? This paper presents a new method for assessing the net traffic congestion effects associated with streetcar operations in Melbourne, Australia, which has the largest streetcar network in the world. Impacts were determined with the use of a traffic network model to compare congestion with trams and without trams. The positive impacts of trams were estimated by using mode shift from tram to automobile when tram services were removed. Negative impacts were explored by considering streetcar traffic operations, the impact of curbside tram stops, and the effect of exclusive priority tram lanes on traffic flow. Findings show that the streetcar network in inner Melbourne results in a net congestion benefit to traffic; a 3.4% decrease in vehicle time traveled and total delay on the road network was established. The streetcar network also contributes to reducing the number of moderately congested links by 16%. Areas for future research are suggested, such as exploring the spatial distribution of the mode shift to automobile and the long-term effect of trams on traffic.


2021 ◽  
Vol 2021 ◽  
pp. 1-22
Author(s):  
Binghong Pan ◽  
Jinfeng Ying ◽  
Shasha Luo ◽  
Yang Shao ◽  
Shangru Liu ◽  
...  

As the number of vehicles continues to grow in China, the problem of urban traffic congestion gets more serious, particularly at intersections. As a new type of unconventional intersection, the displaced left-turn (DLT) intersection has been widely recognized to improve the efficiency of intersections with heavy left-turn traffic flows. Converting an existing intersection into an intersection with additional DLT lanes is a valuable solution. However, the studies on DLT intersections mainly focus on performance, applicability, and safety. The guidelines on the specific engineering design process mostly come from experience, and the study on the considering multifactor design method is still insufficient. Therefore, this paper proposed an evaluation and analysis model of the lengths of added DLT lanes based on the entropy evaluation method, in which VISSIM and Surrogate Safety Assessment Model (SSAM) software were adopted for simulation. A design process for the length of the added DLT lanes was proposed with this model. An urban intersection in Xi’an was taken as a case study, and the application of the model and the design process was studied in detail. After selecting four evaluation indicators, the model was applied to calculate and analyze the optimal length of the added DLT lanes under 45 different traffic volume combinations. The recommended lengths of different situations were within the range recommended in the guidebook published by Federal Highway Administration. The results of the case study proved that the model proposed in this paper was advanced, reasonable, and practical.


2018 ◽  
Vol 15 (1) ◽  
pp. 55-72
Author(s):  
Herlin Hamimi ◽  
Abdul Ghafar Ismail ◽  
Muhammad Hasbi Zaenal

Zakat is one of the five pillars of Islam which has a function of faith, social and economic functions. Muslims who can pay zakat are required to give at least 2.5 per cent of their wealth. The problem of poverty prevalent in disadvantaged regions because of the difficulty of access to information and communication led to a gap that is so high in wealth and resources. The instrument of zakat provides a paradigm in the achievement of equitable wealth distribution and healthy circulation. Zakat potentially offers a better life and improves the quality of human being. There is a human quality improvement not only in economic terms but also in spiritual terms such as improving religiousity. This study aims to examine the role of zakat to alleviate humanitarian issues in disadvantaged regions such as Sijunjung, one of zakat beneficiaries and impoverished areas in Indonesia. The researcher attempted a Cibest method to capture the impact of zakat beneficiaries before and after becoming a member of Zakat Community Development (ZCD) Program in material and spiritual value. The overall analysis shows that zakat has a positive impact on disadvantaged regions development and enhance the quality of life of the community. There is an improvement in the average of mustahik household incomes after becoming a member of ZCD Program. Cibest model demonstrates that material, spiritual, and absolute poverty index decreased by 10, 5, and 6 per cent. Meanwhile, the welfare index is increased by 21 per cent. These findings have significant implications for developing the quality of life in disadvantaged regions in Sijunjung. Therefore, zakat is one of the instruments to change the status of disadvantaged areas to be equivalent to other areas.


2021 ◽  
Vol 8 ◽  
pp. 237437352110180
Author(s):  
Robin E. McAtee ◽  
Laura Spradley ◽  
Leah Tobey ◽  
Whitney Thomasson ◽  
Gohar Azhar ◽  
...  

Millions of Americans live with dementia. Caregivers of this population provide countless hours of multifaceted, complex care that frequently cause unrelenting stress which can result in immense burden. However, it is not fully understood what efforts can be made to reduce the stress among caregivers of persons with dementia (PWD). Therefore, the aim of this pretest–posttest designed study was to evaluate changes in caregiver burden after providing an educational intervention to those caring for PWD in Arkansas. Forty-one participants completed the Zarit Caregiver Burden Scale before and after attending a 4-hour dementia-focused caregiving workshop. The analysis of the means, standard deviations, and paired t tests showed that there was an increase in the confidence and competence in caring for PWD 30 to 45 days after attending the workshop. Health care providers need to understand both the vital role caregivers provide in managing a PWD and the importance of the caregiver receiving education about their role as a caregiver. Utilizing caregiver educational programs is a first step.


2021 ◽  
Vol 13 (8) ◽  
pp. 4437
Author(s):  
Sitti Asmah Hassan ◽  
Intan Nurfauzirah Shafiqah Hamzani ◽  
Abd. Ramzi Sabli ◽  
Nur Sabahiah Abdul Sukor

Bus rapid transit (BRT) is one of the strategies to promote improvements in urban mobility. In this study, BRT scenarios, which integrate exclusive bus lanes and bus priority signal control in mixed traffic scenarios, were modelled using a VISSIM microsimulation. Three scenarios of BRT were modelled to represent 16:84, 38:62 and 54:46 modal splits between public transport and private vehicles. It was found that Scenario 4 (the 54:46 scenario) offers better benefits in terms of delay time saving and economic benefits. In general, it was found that the BRT system enhances the functioning of the transport system and provides people with faster and better mobility facilities, resulting in attractive social and economic benefits, especially on a higher modal split of public transport. It is regarded as one strategy to alleviate traffic congestion and reduce dependency on private vehicles. The finding of this study provides an insight on the effective concept of the BRT system, which may promote the dissemination of an urban mobility solution in the city. The results can help policymakers and local authorities in the management of a transport network in order to ensure reliable and sustainable transport.


SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A140-A141
Author(s):  
Emma Zhao ◽  
Afik Faerman ◽  
David Spiegel

Abstract Introduction Hypnosis-based interventions have been shown to have a positive impact on several dimensions of sleep health. However, current evidence is limited as only a paucity of studies included populations with sleep complaints. Here we present a pilot data set to demonstrate the feasibility of developing a hypnosis-based adjunctive treatment for subjective sleep complaints. Methods Eleven adults (42% female; mean age 45±16.87 years) who sought treatment at the Stanford Sleep Medicine Center or Center for Integrative Medicine for subjective sleep complaints received hypnosis as adjunctive treatment. Self-report questionnaires were used to assess the weekly frequency of subjective sleep disturbances experienced before and after treatment, as well as 5-point Likert scale ratings of perceived qualitative improvement in symptom severity and overall sleep quality. Results Five participants (45%) reported a reduction in symptom frequency and severity after hypnosis treatment. All five participants attributed at least some of the improvement to hypnosis treatment. Most participants (63%) observed post-treatment improvements in their overall sleep quality. No participants reported adverse effects of hypnosis. Conclusion Results suggest hypnosis-based adjunctive treatment may be effective for alleviating subjective sleep disturbances. The findings serve as preliminary support for further randomly controlled trials in larger samples. Support (if any):


2021 ◽  
pp. 232020682110034
Author(s):  
Hamad Alzoman ◽  
Khalid Alamoud ◽  
Waad K. Alomran ◽  
Abdullazez Almudhi ◽  
Naif A. Bindayel

Aim: To evaluate the periodontal status before and after orthodontic treatment and to analyze the confounding factors associated with it. Materials and Methods: The present retrospective study analyzed pre- and posttreatment records of a total of 60 patients. Intraoral digital photographs before and after the orthodontic treatment were used to measure the following three periodontal variables: (a) width of the keratinized gingiva, (b) gingival recession, and (c) the status of interdental papilla. The ImageJ 46 software imaging program was used to perform the required measurements. The clinical data were then analyzed in an association with the participants’ demographic data, the type of orthodontic tooth movement, and other confounding factors. The data obtained were manually entered into the statistical package and analyzed using a significance level set at P < .05. Descriptive statistics, paired t-tests, and Pearson’s correlation analysis were used to identify differences among the studied variables. Results: Among the 60 patients, the majority (66.7%) were females. Most cases of the treated malocclusion were Class II, and most patients underwent intrusion and retrusion movements. The width of keratinized gingiva increased for most sites of upper teeth. In contrast, the lower teeth showed a mix of improvement and compromised width of keratinized gingiva. As a measure of gingival recession, the difference of clinical crown height revealed the tendency toward a reduced clinical crown height for most sites. Upper left lateral incisors and canines showed significant values with regard to keratinized gingival width measurements and tooth movements such as extrusion and intrusion movements. Likewise, with regard to the clinical crown height, upper right central incisors showed significant differences when correlated with the interincisal angle, lower incisors to the mandibular plane, and upper incisors to the NA line. The upper lateral incisors also showed significant correlations to certain cephalometric measurements. Conclusions: The orthodontic treatment was found to exert a significantly positive impact on the surrounding periodontium, particularly in the upper canine areas. Likewise, various types of tooth movement were found to positively affect the periodontium.


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