Bus Transfer Research Articles

Разработка интеллектуальной релейной защиты в сочетании с быстродействующим автоматическим вводом резерва

Разработка интеллектуальной релейной защиты в сочетании с быстродействующим автоматическим вводом резерва

Exploring the effects of perceived values, free bus transfer, and penalties on intermodal metro–bus transfer users' intention

This study examines metro passengers who use intermodal transfer service during their metro system and bus travel and develops research hypotheses based on the perceived value theory. The intentions of potential and retained passengers to use intermodal transfer are influenced by the different amounts of information they possess as well as potential intermodal transfer penalties and benefits (perceived value and free bus transfer). Thus, this study adopts the information processing theory to investigate such behavior intentions and to derive various market segmentation strategies between potential and retained passengers concerning their transfer service use. We also look at the interrelationships between the two main constructs, transfer penalties and benefits, and adopt structural equation modeling to test our hypotheses. The analytical results show that perceived transfer penalties, perceived values, and free bus transfer all influence metro–bus transfer intentions. Perceived value is the most essential determinant of behavioral intention among all the other attributes related to transit transfer in this study and can mediate the relationship between free bus transfer and transfer intentions. The study's conclusions have managerial implications for metro system and bus system agencies and may be applied to intermodal transfer services in other transportation industries. Perceived value of metro–bus transfer service usage can possibly be elevated through the following measures: timetable coordination between metro and bus agencies, passenger guidance information, comfortable bus shelters and waiting environment provisions, low-floor bus services, and smart card integration between the metro and buses.

Analysis of robustness of urban bus network**Project supported by the National Natural Science Foundation of China (Grant Nos. 61473073, 61374178, 61104074, and 61203329), the Fundamental Research Funds for the Central Universities (Grant Nos. N130417006, L1517004), and the Program for Liaoning Excellent Talents in University (Grant No. LJQ2014028).

In this paper, the invulnerability and cascade failures are discussed for the urban bus network. Firstly, three static models(bus stop network, bus transfer network, and bus line network) are used to analyse the structure and invulnerability of urban bus network in order to understand the features of bus network comprehensively. Secondly, a new way is proposed to study the invulnerability of urban bus network by modelling two layered networks, i.e., the bus stop-line network and the bus line-transfer network and then the interactions between different models are analysed. Finally, by modelling a new layered network which can reflect the dynamic passenger flows, the cascade failures are discussed. Then a new load redistribution method is proposed to study the robustness of dynamic traffic. In this paper, the bus network of Shenyang City which is one of the biggest cities in China, is taken as a simulation example. In addition, some suggestions are given to improve the urban bus network and provide emergency strategies when traffic congestion occurs according to the numerical simulation results.

Behavioural micro-dynamics of car ownership and travel in the Seattle metropolitan region from 1989 to 2002

In this paper data from 230 households observed in ten different occasions (waves) from 1989 to 2002 in the Puget Sound region are used to explore relationships among number of cars owned, number of trips driving alone, and number of trips sharing cars with household members. Using a mixture latent class Markov model we identify four distinct groups that are a High Mobility group with more cars and car trips, an Average Mobility group with lower car ownership and trips driving alone, a third group with relatively high car ownership but few car sharing trips, and a fourth group of Low Mobility characterized by the low car ownership and trips. Households change behaviour adapting to internal and external changes to their environment but they also anticipate changes and go through a "preparation" stage (e.g., adding another car in their fleet in expectation of adding another employed person). Land use plays a somewhat secondary role. The analysis also reveals three classes (hidden Markov chains) of households underlying behavioural dynamics with increases in the low car ownership categories (zero and one car per household), decreases in the high car ownership (three cars and four or more cars per household) and stable behaviour in the two cars per household group. Household membership in these classes is significantly influenced by householder ratings to parking availability, schedule flexibility, bus transfers, and day-to-day costs of driving. The findings here show attitudes and land use enhance understanding of longitudinal heterogeneity.

Motor Reacceleration to Improve Process Uptime

Reacceleration is a method of automatically restarting motors after an unexpected deacceleration caused by system voltage events such as dips, outages, or bus transfers. Reacceleration schemes are designed to minimize process disruptions by rapid detection of supply loss, recovery/ monitoring of acceptable transient torque limits, and then automatic reclosure of the motor contactors. Depending on the connected load and minimum available fault current, the reacceleration may be “instantaneous” or a staged event designed to assure that the bus voltage is maintained at an acceptable level during the process restart. Poor coordination of the reacceleration process may cause further system outages if the nominal bus voltage drops below tolerable levels. Special consideration is required to prioritize loads, to maintain production, to prevent lifting of safety valves, and to avert equipment damage. Various processes differ in their ability to withstand temporary outages, from milliseconds (ms) to several seconds. Today's protection and control intelligent electronic devices (IEDs) provide settings, dedicated measurement, and timing circuits to allow these variances to be preprogrammed and activated based on outage duration and magnitude. Short-time outages within millisecond range combined with electrically held contactors provide the least complex situations for enabling a reacceleration system. More complex situations arise when motors are still decelerating and when the supply is restored, especially if the contactors were maintained closed during the outage. Certain more advanced IEDs also provide multiple reacceleration schemes that are automatically deployed based on longer outages—typically up to 30 min.

IEC 61850-based parallel bus transfer scheme for industrial substations

IEC 61850-based parallel bus transfer scheme for industrial substations

A novel bus transfer mode (AS transfer) and a performance evaluation methodology

This paper proposes an innovative on-Chip bus transfer mode – the Advanced Encryption Standard (AES) state transfer (AS) and a performance evaluation methodology to estimate the transfer performance. By modeling and collecting several performance metrics including bus latency, bandwidth, valid bandwidth, power and energy consumption using the methodology, it enhances fidelity of the performance analysis and evaluation. As a case study, we formally complete the hardware implementation flow on Advanced High-Performance Bus (AHB), Advanced eXensible Interface 4 (AXI4) and AS bus (ASBUS) DMA, and demonstrate high estimation accuracy by comparing all the experimental results. Both static analysis and hardware implementation results show that the data transfer latency is close to 29% of AHB and 58% of AXI4 by using the AS transfer. Moreover, it is observed that this high-efficiency transfer mode of ASBUS helps to enhance the valid data bandwidth to around 3.4 times that of AHB and 1.7 times that of AXI4, and the energy consumption of ASBUS is only a half of AHB and AXI4. Furthermore, the proposed evaluation methodology is effectively used with sufficient accuracy (the average estimation error: 3.3%) in the design flow.

A Compensated DFT-Based Phase-Angle Estimation for Fast Motor-Bus Transfer Applications

Motor-bus transfer systems are designed to maintain process continuity during the transfer of a motor bus from one power source to an alternate power source. A proper motor-bus transfer system must be designed in such a way that it can operate fast, and prevent damages to the motors and loads connected to the transferred bus. This paper investigates the application challenges associated with the design of a fast motor-bus transfer system. The paper also proposes a compensated discrete-Fourier-transform-based algorithm that enables a fast and reliable bus transfer for power generating plants and industrial facilities. The main advantage of the proposed algorithm is its simple implementation using the commercially available relay technologies. The effectiveness of the proposed algorithm is validated through comprehensive digital simulation of realistic motor-bus transfer systems in the PSCAD/EMTDC and MATLAB software environments.

Research on urban public traffic network with multi-weights based on single bus transfer junction

Regarding single bus transfer junction as a research object, this paper constructs the urban traffic network models with multi-weights taking different bus lines in bus transfer junction as the network nodes, that is, the urban traffic network with multi-weights is given different properties weights at every edge. According to the method of network split, the complex network with multi-weights is split into several different single weighted complex networks. Then, we study the global synchronization of the new network model by changing congestion degrees, transfers coefficient and passenger flow density between different bus lines. Finally, analytical and simulated results are given to show the impact of different properties weights to the public traffic network balance.

Quantifying transit travel experiences from the users’ perspective with high-resolution smartphone and vehicle location data: Methodologies, validation, and example analyses

While transit agencies have increasingly adopted systems for collecting data on passengers and vehicles, the ability to derive high-resolution passenger trajectories and directly associate them with transit vehicles in a general and transferable manner remains a challenge. In this paper, a system of integrated methods is presented to reconstruct and track travelers usage of transit at a detailed level by matching location data from smartphones to automatic transit vehicle location (AVL) data and by identifying all out-of-vehicle and in-vehicle portions of the passengers trips. High-resolution travel times and their relationships with the timetable are then derived. Approaches are presented for processing relatively sparse smartphone location data in dense transit networks with many overlapping bus routes, distinguishing waits and transfers from non-travel related activities, and tracking underground travel in a Metro network. The derived information enables a range of analyses and applications, including the development of user-centric performance measures. Results are presented from an implementation and deployment of the system on San Francisco’s Muni network. Based on 103 ground-truth passenger trips, the detection accuracy is found to be approximately 93%. A set of example applications and findings presented in this paper underscore the value of the previously unattainable high-resolution traveler-vehicle coupled movements on a large-scale basis.

Efficiency and robustness of different bus network designs

We compare the efficiencies and robustness of four transport networks that can be possibly formed as a result of deliberate city planning. The networks are constructed based on their spatial resemblance to the cities of Manhattan (lattice), Sudan (random), Beijing (single-blob) and Greater Cairo (dual-blob). For a given type, a genetic algorithm is employed to obtain an optimized set of the bus routes. We then simulate how commuter travels using Yen's algorithms for k shortest paths on an adjacency matrix. The cost of traveling such as walking between stations is captured by varying the weighted sums of matrices. We also consider the number of transfers a posteriori by looking at the computed shortest paths. With consideration to distances via radius of gyration, redundancies of travel and number of bus transfers, our simulations indicate that random and dual-blob are more efficient than single-blob and lattice networks. Moreover, dual-blob type is least robust when node removals are targeted but is most resilient when node failures are random. The work hopes to guide and provide technical perspectives on how geospatial distribution of a city limits the optimality of transport designs.

Investigations on Requirements for UHV/EHV AC Switchgear by CIGRE Study Committee A3

On request of IEC Technical Subcommittee 17A, CIGRE Study Committee A3 “High Voltage Equipment” investigated the requirements for ultra-high voltage ac switchgear, especially for parameters which cannot be extrapolated linearly from the corresponding equipment characteristics with lower-rated voltage, namely 800 kV. For circuit breakers, such aspects are the first pole-to-clear factor, the amplitude factor, the time to peak to define the transient recovery voltage envelope, the surge impedance of overhead lines, the damping and refraction of traveling waves, long-line faults, transformer-limited faults, initial transient recovery voltage, and the influence of shunt and series compensation. Disconnectors utilized for interrupting the bus transfer currents, bus charging currents and very fast transients, ground switches used for interrupting induced line currents, and high-speed ground or earthing switches have been studied as well. Based on these system and substation studies and simulations, recommendations have been provided to IEC SC 17A.

Predictors of repeated “no-showing” to clinic appointments

ObjectiveTo determine the variables that contribute to repeated patient non-compliance with showing up to clinic appointments. Study designRetrospective chart review. SettingSingle tertiary care academic institution. Subjects and MethodsPatients who did not show up to 3 or more clinic appointments in the otolaryngology department in the Henry Ford Health System in metro Detroit, Michigan between July 1, 2011 to June 30, 2012 area were compared to control patients randomly chosen from those who had appointments on the same day with the same provider as the no-show patients. Results105 patients were identified who no-showed to 3 or more clinic appointments. Younger age, black race, and lower income were all found to be significant factors for patients missing appointments in a multiple variate model. On logistic regression, Medicaid insurance, closer distance from home to appointment, less bus transfers, and less time by bus travel were also found to correlate with no-showing. ConclusionAge, race, and income are significantly related to patient non-compliance with clinic appointments. Paradoxically, proximity to the clinical appointment location is also significantly related – we hypothesize this may be the result of significant income inequality in the metro Detroit population distribution. Follow up studies include analyzing factors that precluded patient access and interventions to improve compliance and decrease cost.

A new MV bus transfer scheme for nuclear power plants

Fast bus transfer method is the most popular and residual voltage transfer method that is used as a backup in medium voltage buses in general. The use of the advanced technology like open circuit voltage prediction and digital signal processing algorithms can improve the reliability of fast transfer scheme. However, according to the survey results of the recent operation records in nuclear power plants, there were many instances where the fast transfer scheme has failed. To assure bus transfer in any conditions and circumstances, uninterruptible bus transfer scheme utilizing the state of the art medium voltage UPS is discussed and elaborated.

Model of Bus and Urban Rail Transfer Behavior Based on General Cost Function

To design an efficient feeder bus route network and develop a better integrated intermodal system, it is necessary to study travelers' mode choice behavior. This paper focuses on the transfer behavior model between bus transit and urban rail. Based on the theory of Binary logit (BL) model, a new generalized travel cost model (GTC) which considers the influencing factors including travel distance, travel cost, and transfer time is established, and the choice model of bus and urban rail with the influence of transfer behavior is built. Then, a deeper analyzing process is conducted to get the significance of the model. In addition, the accuracy and feasibility of the model are verified through using the real survey data. Finally, according to the model results, some countermeasures consisting of improving the transfer condition and optimizing price charging pattern are given to promote a better public transportation system.

Variables for Repeated No‐Showing to Clinic Appointments

Objectives: Determine the variables that contribute to non-compliance with showing up to clinic appointments. Patients no-showing to their appointments represent a significant burden to the health care system by decreasing access to care and lost potential revenue. Identifying patient factors correlated with missed appointments may help characterize why these appointments are missed and identify opportunities to help patients get the care they need. Methods: Retrospective chart review. Patients who did not show up to 3 or more clinic appointments in the otolaryngology department in the Henry Ford system in metro Detroit, Michigan, between July 1, 2011, and June 30, 2012, were analyzed. Controls were patients who had appointments on the same day with the same provider as the no-show patients. Results: A total of 106 patients were identified who no-showed to 3 or more clinic appointments. Younger age, black race, and lower income were found to be significant factors for patients not showing up to appointments on multiple variate model. On logistic regression, Medicaid insurance, closer distance from home to appointment, less bus transfers, and less time by bus travel were also found to be significant for no-showing. Conclusions: Age, race, and income are significant contributors to patient noncompliance with clinic appointments. Paradoxically, proximity to the clinical appointment location is also a significant factor; we hypothesize this may be the result of relative income inequality in the metro Detroit population. Follow-up studies include analyzing severity of patient complaints and weather as a factor of noncompliance.

Evaluation of Public Transit System

To evaluate the comfort, safety, convenience, timeliness, coordination of urban public transport hubs, thereby optimizing planning, following the five evaluation principles, I established a comprehensive evaluation system of urban bus transfer system ,proposed transfer hub noise figure, transfer comfort, the per capita area ,etc.10 hubs evaluation, and gave definitions of indicators, calculation methods and indicators for classification value by a combination of quantitative and qualitative indicators method.

High-Speed Bus Transfer Supervision

This paper explains how to supervise the transfer of an important load bus from one source to another in less than one half-cycle. This supervision is required for large-scale industrial processes such as petroleum refineries.

Evaluation of Gas Insulated Disconnector Switch for Bus Charging and Bus Transfer Currents

Abstract Gas insulated disconnector switches (DSs) are employed in a gas insulated substation (GIS) to interrupt and to make capacitive currents, in principle. During switching of capacitive currents very fast transient over-voltages (VFTOs) are common to DS. Intense VFTOs may result in peak voltage close to basic insulation level (BIL) of the connected equipment, leading to progressive deterioration and secondary breakdowns in very high voltage gas-insulated systems. At the same time, arcing during switching of bus transfer currents, by the DS, is considered as a source of substantial amount of decomposed products. This contamination may result in significant reduction in insulation strength of the medium. In order to ensure reliability of the design, it is essential to establish the DS for bus charging and bus transfer current duties under most onerous service conditions through suitable tests. The optimal design of DS to meet these test duties is established with suitable analytical techniques. The tests, which have been discussed and analyzed as part of this study, were performed on an indigenously developed 145 kV gas insulated DS as per IEC 62271-102. A detailed arrangement of the DS (main and auxiliary) and guidelines for conducting the above tests are also explained. Different performance parameters like arcing time, pre-arcing time, secondary discharges, trapped voltages, and level of contamination are analyzed. The behavior of DS during these evaluations is also reported in the present paper. Finally, the effect of different design parameters on performance of the DS has been analyzed.

Efficient Usage of Transfer based System in Intracity Bus Transit Operation: Sample of Izmir

In this study, intracity bus transit lines based on transfer system are reorganized by using O-D matrix that are obtained from analyzing smart card data. Vertical bus routes that reach the rail system stations are designed and also bus lines that have connection with city center are converted to the regional bus lines. In this way travel times will be decreased thus agency can serve with efficient and reliable bus routes. Decreasing the number of lines and buses that using arterials in the city center can provide more regular headways. Additionally, existing bus line system and transfer based line system are compared and operational benefits (number of vehicles, number of services, total route length, etc.) are examined.