Browse Topic: Public transportation systems

Items (1,144)
This study presents a method to evaluate the daily operation of traditional public transportation using multi-source data and rank transformation. In contrast with previous studies, we focuses on dynamic indicators generated during vehicle operation, while ignoring static indicators. This provides a better reference value for the daily operation management of public transport vehicles. Initially, we match on-board GPS data with network and stop coordinates to extract arrival and departure timetable. This helps us calculate dynamic operational metrics such as dwell time, arrival interval, and frequency of vehicle bunching and large interval. By integrating IC card data with arrival timetable, we can also estimate the number of people boarding at each stop and derive passenger arrival time, waiting time, and average waiting time. Finally, we developed a comprehensive dynamic evaluation method of public transportation performance, covering the three dimensions: bus stops, vehicles, and
Zhou, YangShao, YichangHan, ZhongyiYe, Zhirui
With the acceleration of urbanization, developing public transportation is an important means to alleviate travel pressure and traffic congestion in cities. Work zones that occupy urban road resources affect normal vehicle operations, leading to reduced vehicle efficiency. Based on this, the paper conducts research on traffic flow modeling and simulation analysis for work zones in a vehicle-road coordination environment. Based on the Gipps model and the SCAT model, optimizations and improvements were made to the following and lane-changing rules for three types of vehicles: human-driven vehicles (HVs), autonomous and connected vehicles (CAVs), and buses. Using cellular automata theory, it constructs a running model suitable for mixed traffic flow vehicles in work zones. MATLAB software is utilized to simulate the operation process of vehicles under work zone scenarios, analyzing changes in traffic flow from two directions: road geometric conditions (speed limits) and traffic flow
Xie, RongkaiSun, BoZheng, YunchaoLiao, MeixianZhang, WendiLi, Rui
Aiming at the problem of insufficient capacity of taxiways in hub airports, which combine the safety interval, conflict resolution and fair principles, a taxiway planning model is established by taking the shortest taxiway as the optimisation goal, considering fuel consumption and exhaust emissions. Dijkstra algorithm is used to transform the taxiing path into an adjacency matrix, and conflict resolution is carried out in a weighted way. Under the premise of ensuring zero conflict of taxiways, the total taxiing distance is reduced. Based on actual operational data from a hub airport in China, the results show that the proposed taxiing path planning method is feasible, shortening the aircraft taxiing distance and improving the surface taxiing efficiency.
Feng, BochengQi, XinyueZhang, Hongbin
The COVID-19 pandemic has reshaped public transportation dynamics globally, prompting shifts in passenger behavior and payment methods. Concurrently, the rise of fintech and Industry 4.0 has accelerated the adoption of digital payment solutions, aligning with the trend towards cashless societies. This study investigates the impact of the pandemic on the transition from cash to card payments for public transport fares in Belo Horizonte, Brazil. Leveraging data from the city's transparency portal, analyses were conducted on passenger numbers, payment methods, and card usage from November 2019 to November 2021. Findings reveal a steady usage of card payments compared to cash, with a notable increase in individual ticket card transactions post-vaccination. Conversely, employer-provided transportation voucher card usage experienced a decline. These trends suggest a preference among users for card-based payments, potentially driven by concerns over direct cash handling and adherence to
Rodrigues, CádmoSantos Júnior, Wagner
The world’s commitment towards the mitigation of climate changes has driven many sectors into an effort to reduce their carbon footprint. The transit bus sector, which currently strongly relies on diesel fueled buses, is challenged to reduce its carbon footprint, as well as to reduce the emission of criteria pollutant and noise, which negatively affect the world cities’ population, especially those living nearby the large transit bus corridors. In this context, the Battery Electric Buses (BEB), has been set as the transit sector’s workhorse for reaching the global, regional and local environmental targets. However, despite the relative maturity level of both the electric powertrain and the energy storage devices (ESD) technologies, the bus electrification transition is a disruptive process, from both a technological, operational and managerial standpoint, which might take into account both the (electrical) infrastructure, as well as the operational customization requirements. Moreover
Barbosa, Fábio Coelho
The planning of mountain campus bus routes needs to take into account user demand, convenience, and other factors. This study adopts a comprehensive research method that combines quantitative and qualitative viewpoints. From the perspective of university students, this article studies the demand of campus public transportation and proposes the layout of campus bus routes in mountainous universities to meet the needs of users. The psychological needs questionnaire was used to investigate college students’ expectation of bus station service function. Taking three mountain universities as examples, the integration and selectivity of campus road networks are evaluated by using space syntax analysis, which provides valuable insights into the quality of bus stop areas. This article discusses the correlation between psychological needs assessment of college students and objective conditions of campus road network. The study concludes with the following findings: (1) The pedestrian environment
Duan, RanTang, RuiWang, ZhigangZhao, YixueWang, QidaYang, JiyiSu, Jiafu
The increase in vehicular traffic on Indian roads has led to a significant rise in the frequency of horn usage, particularly in city driving conditions and during peak traffic hours. Existing electro-mechanical horns are designed to have a mission life of 100,000 cycles according to Indian standards IS 1884 [1]. However, the intensified usage patterns have prompted a re-evaluation of the efficacy of these requirements. Studies reveal that the average horn blow frequency for normal usage vehicles is approximately three times per kilometer. When extrapolated to various usage categories, such as public transport and privately owned vehicles, observed increase in average horn blowing frequency per kilometer. When extrapolated, this corresponds to more than 4 lakhs cycles for a vehicle mission life of 2.5 lakhs kilometers. This insight drives the need to review and update validation test specifications to better align with customer usage patterns, thereby enhancing component reliability. By
Joshi, Vivek S.Jape, Akshay
Autonomous vehicles (AVs) are positioned to revolutionize transportation, by eliminating human intervention through the use of advanced sensors and algorithms, offering improved safety, efficiency, and convenience. In India, where rapid urbanization and traffic congestion present unique challenges, AVs still hold a significant promise. This technical paper discusses the relevance of autonomous vehicles in the Indian context and the challenges that need to be addressed before the widespread adoption of autonomous vehicles in India. These challenges include the lack of infrastructure, concerns regarding road safety, software vulnerabilities, adaptability of change towards autonomous vehicles, and the management of traffic. The paper also highlights the government's initiatives to encourage the development and adoption of autonomous vehicles, ideology behind the legal framework and the required changes in terms of technological advancements, and urban planning. In a brief manner, this
Mishra, AdarshMathur, Gaurav
Since the COVID-19 pandemic that advanced contactless service, robots are increasingly being seen conducting routine deliveries around hospitals and hotels. Developed by Robotise Technologies, JEEVES is one such autonomous service robot used in hotels, healthcare facilities, offices, airports, and other settings. Its main duty is to transport materials and products.
The advent of the low-altitude economy represents a novel economic paradigm that has emerged in recent years in response to technological advancement and an expanding social demand. The low-altitude economy is currently undergoing a period of rapid development, which underscores the importance of ensuring the safety of airfield operations. To enhance operational efficiency, unmanned aerial vehicles (UAVs) can be utilized for the inspection of the surrounding area, runway inspection, environmental monitoring, and other tasks. This paper employs TurMass technology, the TurMass gateway is miniaturised as the communication module of FT24, and the TK8620 development board replaces the LoRa RF module in the ELRS receiver to achieve the communication transmission between the remote control and the receiver. Additionally, a TurMass chip is integrated into the UAV to transmit beacons, while an airfield management aerial vehicle is employed to receive nearby UAV data, thereby preventing
Zhang, XiaoyangChen, Hongming
The purpose of this AIR is to establish a baseline for hydrogen fueling protocol and process limits for both gaseous and liquid hydrogen fueling of aircraft (eCTOL, eRotor, eVTOL, LTA) at the airport from small aircraft to wide-body. A further goal is to harmonize and establish common aircraft fueling safety definitions wherever possible with other SAE and EUROCAE standards and NFPA codes alike. Hydrogen fueling process limits (including the fuel temperature, the maximum flow rate, time required, etc.) are affected by factors such as ambient temperature, fuel delivery temperature, and initial pressure in the hydrogen storage system. The further goal is to establish basic fueling protocols within these limits as a starting point while evaluating minimum criteria, including evaluation of fueling with or without communications. AIR8466 establishes the protocol and process limits for hydrogen fueling of aircraft and plans to establish fueling protocols starting with small aircraft
AE-5C Aviation Ground Fueling Systems Committee
This equipment specification covers requirements for airfield liquid anti-icing/deicing equipment for airfield snow removal purposes. The unit shall include a combination of a carrier vehicle, liquid product tank, and dispensing system. This vehicle as a unit shall be an integrated chemical dispensing deicing/anti-icing application system. Primary application is for the liquid chemical application for cleaning of ice and snow from airfield operational areas such as runways, taxiways, and ramp aprons. The term “carrier vehicle” represents the various self-propelled prime movers that provide the motive power necessary to move snow and ice control equipment during winter operations. The airport operator may require this specified piece of equipment in order to maintain the airfield during large and small snow events. When necessary, the airfield liquid anti-icing/deicing chemical applicator (ALAD) shall be a central and critical element in the winter pavement maintenance fleet in the
G-15 Airport Snow and Ice Control Equipment Committee
Autonomous vehicle technologies have become increasingly popular over the last few years. One of their most important application is autonomous shuttle buses that could radically change public transport systems. In order to enhance the availability of shuttle service, this article outlines a series of interconnected challenges and innovative solutions to optimize the operation of autonomous shuttles based on the experience within the Shuttle Modellregion Oberfranken (SMO) project. The shuttle shall be able to work in every weather condition, including the robustness of the perception algorithm. Besides, the shuttle shall react to environmental changes, interact with other traffic participants, and ensure comfortable travel for passengers and awareness of VRUs. These challenging situations shall be solved alone or with a teleoperator’s help. Our analysis considers the basic sense–plan–act architecture for autonomous driving. Critical components like object detection, pedestrian tracking
Dehghani, AliSalaar, HamzaSrinivasan, Shanmuga PriyaZhou, LixianArbeiter, GeorgLindner, AlisaPatino-Studencki, Lucila
US transportation infrastructure is dominated by the automobile form factor. Alternative modalities of movement, such as bikes, golf carts, and other micromobility options, have existed but are decidedly at a lower tier of importance. Even pedestrian access ways are not overly emphasized in the US transportation system. This lack of prioritization matches the reality that the vast majority of people and commerce moves through the motor vehicle infrastructure, with micromobility sitting in the periphery. Additionally, given the current lack of commercial applications, there are limited direct fee-based funding mechanisms connected to micromobility form factors. Micromobility and the Next Infrastructure Wave discusses how recent technological innovations in electrification, e-commerce, and autonomy are enabling a new class of micromobility devices which offer palpable value to consumers and enable significant commercial applications. Unlike the past, these micromobility devices now have
Razdan, Rahul
A challenge of public transportation GPS data is the frequent utilization of monitoring systems with low sampling rates, primarily driven by the high costs associated with cellular data transmission of large datasets. Altitude data is often imprecise or not recorded at all in regions without large elevation changes. The low data quality limits the use of the data for further detailed investigations like a realistic energy consumption forecast for assessing the electrical grid load resulting from charging the vehicle fleet. Modern research often reconstructs speed data only, or uses additional GPS loggers, which is associated with increased costs in the vehicle fleet. The importance of precise and high-quality altitude data and specialized expertise in mountainous regions are frequently overlooked. This paper introduces an efficient new route matching method to reconstruct speed and respective road slope data of a GPS signal sampled at low frequency for a public transportation electric
Hitz, ArneKonzept, AnjaReick, BenediktRheinberger, Klaus
A bearing is a mechanical component that transmits rotation and supports load. Depending on the type of rotating mechanism, bearings are categorized into ball bearings and tapered-roller bearings. Tapered-roller bearings are superior to ball bearings in load-bearing capabilities. They are used in applications where high loads, such as, the wheel bearings for commercial vehicles and trucks, aircraft, high-speed trains, and heavy-duty spindles for heavy machinery must be supported. The demand for reducing the friction torque in automobiles has recently increased owing to carbon-emission regulations and fuel-efficiency requirements. Therefore, research on the friction torque of bearings is essential; studies have been conducted on lubrication, friction, and contact in tapered-roller bearings. There have also been studies on lip friction, roller misalignment, and so on; however, research on the influence of roller geometries and material properties is scarce. This study investigated the
Lee, SeungpyoAn, Hyun Gyu
To identify the influences of various built environment factors on ridership at urban rail transit stations, a case study was conducted on the Changsha Metro. First, spatial and temporal distributions of the station-level AM peak and PM peak boarding ridership are analyzed. The Moran’s I test indicates that both of them show significant spatial correlations. Then, the pedestrian catchment area of each metro station is delineated using the Thiessen polygon method with an 800-m radius. The built environment factors within each pedestrian catchment area, involving population and employment, land use, accessibility, and station attributes, are collected. Finally, the mixed geographically weighted regression models are constructed to quantitatively identify the effects of these built environment factors on the AM and PM peak ridership, respectively. The estimation results indicate that population density and employment density have significant but opposite influences on the AM and PM peak
Su, MeilingLiu, LingChen, XiyangLong, RongxianLiu, Chenhui
In the evolving landscape of automated driving systems, the critical role of vehicle localization within the autonomous driving stack is increasingly evident. Traditional reliance on Global Navigation Satellite Systems (GNSS) proves to be inadequate, especially in urban areas where signal obstruction and multipath effects degrade accuracy. Addressing this challenge, this paper details the enhancement of a localization system for autonomous public transport vehicles, focusing on mitigating GNSS errors through the integration of a LiDAR sensor. The approach involves creating a 3D map using the factor graph-based LIO-SAM algorithm, which is further enhanced through the integration of wheel encoder and altitude data. Based on the generated map a LiDAR localization algorithm is used to determine the pose of the vehicle. The FAST-LIO based localization algorithm is enhanced by integrating relative LiDAR Odometry estimates and by using a simple yet effective delay compensation method to
Kramer, MarkusBeierlein, Georg
The winged body reusable launch vehicle needs to be tested and evaluated for its functionality during the pre-flight preparation at the runway. The ground based checkout systems for the avionics and the actuator performance testing during pre-flight evaluation are not designed for rapid movement. This new kind of launch vehicle with solid rocket first-stage and winged body upper-stage demands the system testing at Launchpad and at the runway. The safety protocol forbids the permanent structure for hosting the checkout system near runway. The alternative is to develop a rapidly deployable and removable checkout system. A design methodology adopting conventional industrial instrumentation systems and maintaining mobility is presented. This paper presents the design and development of a mobile checkout system for supporting the ground pre-flight testing during autonomous flight landing trials.
V, Vivekanand
The impending deployment of automated vehicles (AVs) represents a major shift in the traditional approach to ground transportation; its effects will inevitably be felt by parties directly involved with vehicle manufacturing and use (e.g., automotive original equipment manufacturers (OEMs), public transportation systems, heavy goods transportation providers) and those that play roles in the mobility ecosystem (e.g., aftermarket and maintenance industries, infrastructure and planning organizations, automotive insurance providers, marketers, telecommunication companies). The focus of this chapter is to address a topic overlooked by many who choose to view automated driving systems and AVs from a “10,000-foot perspective:” the topic of how AVs will communicate with other road users such as conventional (human-driven) vehicles, bicyclists, and pedestrians while in operation. This unsettled issue requires assessing the spectrum of existing modes of communication—both implicit and explicit
Beiker, SvenRazdan, RahulFavaro, FrancescaTaiber, JoachimSell, Raivo
When the aircraft towing operations are carried out in narrow areas such as the hangars or parking aprons, it has a high safety risk for aircraft that the wingtips may collide with the surrounding aircraft or the airport facility. A real-time trajectory prediction method for the towbarless aircraft taxiing system (TLATS) is proposed to evaluate the collision risk based on image recognition. The Yolov7 module is utilized to detect objects and extract the corresponding features. By obtaining information about the configuration of the airplane wing and obstacles in a narrow region, a Long Short-Term Memory (LSTM) encoder-decoder model is utilized to predict future motion trends. In addition, a video dataset containing the motions of various airplane wings in real traction scenarios is constructed for training and testing. Compared with the conventional methods, the proposed method combines image recognition and trajectory prediction methods to describe the relative positional relationship
Zhu, HengjiaXu, YitongXu, ZiShuoJiYuan, LiuZhang, Wei
The study emphasizes transitioning school buses from diesel to electric to mitigate their environmental impact, addressing challenges like limited driving range through predictive models. This research introduces a comprehensive control-oriented model for estimating auxiliary loads in electric school buses. It begins by developing a transient thermal model capturing cabin behavior, divided into passenger and driver zones. Integrated with a control-oriented HVAC model, it estimates heating and cooling loads for desired cabin temperatures under various conditions. Real-world operational data from school bus specifications enhance the model’s practicality. The models are calibrated using experimental cabin-HVAC data, resulting in a remarkable overall Root Mean Square Error (RMSE) of 2.35°C and 1.88°C between experimental and simulated cabin temperatures. A lateral powertrain model has been developed that encompasses vehicle dynamics, electric machinery, transmission, and electrical loads
Nawaz, MuneebullahAlsharif, KhaledHanif, AtharAhmed, Qadeer
Given the growing interest in improving the efficiency of the bus fleet in public transportation systems, this paper presents an analysis of the energy consumption of a battery electric bus. During the experimental campaign, a battery electric bus was loaded using sand payloads to simulate the passenger load on board and followed another bus during regular service. Data related to the energy consumed by various bus utilities were published on the vehicle’s CAN network using the FMS standard and sampled at a frequency of 1 Hz. The collected experimental data were initially analyzed on a daily basis and then on a per-route basis. The results reveal the breakdown of energy consumption among various utilities over the course of each day of the experiment, highlighting those responsible for the highest energy consumption. Subsequently, the relationship between the energy consumption of the traction motor and the climate control system was investigated concerning environmental parameters
Belloni, MattiaTarsitano, DavideSabbioni, Edoardo
This document includes recommendations of installations of adequate landing and taxiing lighting systems in aircraft of the following categories: a Single engine personal and/or liaison type b Light twin engine c Large multiengine propeller d Large multiengine turbojet e Military high-performance fighter and attack f Helicopter g Electric Vertical Takeoff and Landing (EVTOL) and Urban Air Mobility (UAM)
A-20B Exterior Lighting Committee
This specification covers runway deicing and anti-icing products in the form of a liquid. Unless otherwise stated, all specifications referenced herein are latest (current) revision.
G-12RDP Runway Deicing Product Committee
This specification covers a runway deicing and anti-icing product in the form of a solid. Unless otherwise stated, all specifications referenced herein are latest (current) revision.
G-12RDP Runway Deicing Product Committee
The use of appropriate loads and regulations is of great importance in weld fatigue assessment of rail on-track maintenance equipment and similar vehicles for optimized design. The regulations and available loads, however, are often generalized for several categories, which proves to be overly conservative for some specific categories of machines. EN (European Norm) and AAR (Association of American Railroads) regulations play a pivotal role in determining the applicable loads and acceptance criteria within this study. The availability of track-induced fatigue load data for the cumulative damage approach in track maintenance machines is often limited. Consequently, the FEA-based validation of rail track maintenance equipment often resorts to the infinite life approach rather than cumulative damage approach for track-induced travel loads, resulting in overly conservative designs. The work presented in this article evaluates and compares the weld fatigue damage of track maintenance
Patil, DipakPetersen, Michael
A bus is integral part of public transportation in both rural and urban areas. It is also used for scheduled transport, tourism, and school transport. Buses are the common mode of transport all over the world. The growth in economy, the electrification of public transport, demand in shared transport, etc., is leading to a surge in the demand for buses and accelerating the overall growth of the bus industry. With the increased number of buses, the issue of safety of passengers and the crew assumes special importance. The comfort of driver and passenger in the vehicle involves the vibration performance and therefore, the structural integrity of buses is critically important. Bus safety act depicts the safety and comfort of bus operations, management of safety risks, continuous improvement in bus safety management, public confidence in the safety of bus transport, appropriate stakeholder involvement and the existence of a safety culture among bus service providers. In order to provide
Bijwe, Vilas B.Mahajan, RahulVaidya, RohitPatel, KaustubhHiwale, DiwakarWalke, Abhijit Ashok
India is a highly populous country. The traffic problems faced by the people here are not uncommon. The increase in traffic leads to increase in accidents, pollution, inconvenience and frustration. It also comes with costs of additional fuel and time. Though public transport is extensively available in India, still it isn't sufficient for the population of India. Especially in Metro cities, public transport services are often crowded. So, to travel peacefully people are opting for commuting in their own vehicles. And as a result, more vehicles are coming on roads. Other major reasons for increasing traffic are lack of proper implementation of traffic rules and traffic signals out of sync. In addition to city traffic, congestion is also seen on highways, mainly at toll plazas. Although implementation of FASTag has reduced it to some extent, some toll plazas still face traffic congestion issues. This paper provides an idea to ease the traffic problems in the city and on the highways too
Jain, Pritesh
The transport sector in all domains like personal vehicles, public transport and logistics has seen a tremendous growth over the past decade, more so in the last 5 years. The main reasons for this rapid growth is the development of new energy storage systems in battery technology (Lithiumion, sodium ion, aluminum air etc.), hydrogen fuel cells, super capacitors etc. On the other hand there has been tremendous development in the motor drive technology with the availability of brushless dc motors (BLDC Motors), induction motors, Permanent magnet synchronous motors (PMSM, IPMSM). Each motor having its own special characteristics and usage suited for a very specific application in terms of torque and load bearing capacities. In this paper we describe a unique platform with twin motor drive system electric vehicle which is powered by an artificial intelligence (AI) enabled electronic module DuoPackR. The basic platform is described with the help of a bicycle which has two BLDC motors on the
Pratiwadibhayankaram, Ashwini Kumar KrishnaswamyK A, RakeshSangam, Manjunath
Prime concern for electric vehicle where the application of the vehicle is public transport, is the charging of vehicle and operation of its infrastructure. Such an example of operating the EV buses is under the GCC (gross cost contract) model, with high operation time and comparatively lesser time for charging. It is challenging to meet these requirements. To counter this situation in fleet operated busses it is proposed to adapt an automated charging method which involves minimum man power intervention and automated mechanism to connect & disconnect the charging connectors. This paper proposes an automated pantograph mechanism based method of charging EV buses, meeting requirements as per SAE J3105 & ISO 15118 standards, which would be an ideal way to resolve the current situation. In the above mentioned pantograph type charging, the charging station or depot will have an infrastructure including charger whose input will be from grid, and the charging dispenser will be pantographs
Gullyal, AvinashAhmed, YasirAmancharla, Naga ChaithanyaKinjalkar, Milind
The advent of autonomous vehicles promises to revolutionize the transportation sector globally, and India, as one of the world's fastest-growing economies, stands at the forefront of this transformative technology. This paper presents a brief overview of the current state and potential implications of autonomous vehicles in the Indian context. With its densely populated cities, diverse traffic conditions, and complex road infrastructure, India presents unique challenges and opportunities for the deployment of autonomous vehicles. This technology has the potential to address critical issues such as road safety, congestion, and pollution while transforming the mobility experience for millions of people. However, several hurdles must be overcome to fully harness its benefits. The paper explores key considerations for the implementation of autonomous vehicles in India. These include adapting the technology to navigate chaotic traffic scenarios, addressing infrastructure limitations, and
Shetty, Sharan Harish
The battery electric buses (BEB) are set as key tools to enable cities to meet their challenging transport environmental targets, i.e. the reduction of Greenhouse gas (GHG) emissions, improvement of local air quality, as well as to provide a quieter system for both passengers and the urban community. The recent evolutions of the traction battery technology, with increasing battery energy and power densities, battery durability and dynamic performance, driven by both the light and heavy duty vehicles segment, has opened the way for a series of transit bus electrification initiatives, focused on the evaluation of the feasibility of the BEB technology for the zero local emission bus fleet targets, already set by transit authorities in some important cities worldwide. In this context, as important as the onboard electric traction technology itself, currently already mature for BEB test trials, is the required electric charging infrastructure and its inherent operational effects, which
Barbosa, Fábio C.
Nowadays, the rapid growth of civil aviation transportation demand has led to more frequent flight delays. The major problem of flight delays is restricting the development of municipal airports. To further improve passenger satisfaction, and reduce economic losses caused by flight delays, environmental pollution and many other adverse consequences, three machine learning algorithms are constructed in current study: random forest (RF), gradient boosting decision tree (GBDT) and BP neural network (BPNN). The departure flight delay prediction model uses the actual data set of domestic flights in the United States to simulate and verify the performance and accuracy of the three models. This model combines the visual analysis system to show the density of departure flight delays between different airports. Firstly, the data set is reprocessed, and the main factors leading to flight delays are selected as sample attributes by principal component analysis. Secondly, the mean absolute error
Qi, XinyueQian, PinzhengZhang, Jian
Transporting baggage is critical in airport ground support services to ensure smooth flight operations. However, the scheduling of baggage transport vehicles faces challenges related to low efficiency and high costs. A multi-objective optimization vehicle scheduling model is proposed to address these issues, considering time and space costs, vehicle utilization, and passenger waiting time. An improved genetic algorithm (IGA) based on the large-scale neighborhood search algorithm is proposed to solve this model. The simulation experiment is conducted using actual flight data from an international airport. The IGA algorithm is compared with the standard genetic algorithm (SGA) based on experimental results, revealing that the former achieves convergence in a significantly shorter time. Moreover, the scheduling paths of baggage cars that violate flight service time window requirements are significantly lower in the final scheduling scheme under the IGA algorithm than in SGA. Additionally
Jiang, HanZhang, JianZhang, HaiyanQian, Pinzheng
Given the rapid advancement of connected and automated transportation, its applications have significantly increased. They are being studied worldwide to shape the future of mobility. Key promises are a more comfortable, efficient and socially adapted kind of mobility. As part of the EU Horizon2020 project SHared automation Operating models for Worldwide adoption (SHOW), the Karlsruhe Test Site in the Test Area Autonomous Driving Baden-Württemberg (TAF-BW) addresses aspects of scalability to overcome challenges, which have so far hindered market penetration of this future-oriented kind of mobility. The explored services, including passenger and cargo transport, are closely linked to the daily travel requirements of road users, particularly in peri-urban areas, to cover the last mile of their journeys, connecting them to public transport. The provided high-definition maps and the smart and intelligent roadside infrastructure of TAF-BW facilitate the testing and evaluation of automated
Ochs, SvenFleck, TobiasOrf, StefanSchotschneider, AlbertGontscharow, MartinPolley, RupertZofka, Marc RenéViehl, AlexanderZöllner, J. MariusSimon, KevinFrey, Michael
Ground vibration testing (GVT) is an important phase of the development, or the structural modification of an aircraft program. The modes of vibration and their associated parameters extracted from the GVT are used to modify the structural model of the aircraft to make more reliable dynamics predictions to satisfy certification authorities. Due to the high cost and the extensive preparations for such tests, a new method of vibration testing called taxi vibration testing (TVT) rooted in operational modal analysis (OMA) was recently proposed and investigated by the German Institute for Aerospace Research (DLR) as alternative to conventional GVT. In this investigation, a computational framework based on fully coupled flexible multibody dynamics for TVT is presented to further investigate the applicability of the TVT to flexible airframes. The time domain decomposition (TDD) method for OMA was used to postprocess the response of the airframe during a TVT. The framework was then used to
Al-bess, LohayKhouli, Fidel
More airports are starting to adopt and test the use of radio frequency (RF) mitigation techniques to counter the operation of unmanned aircraft systems (UAS) in violation of civilian airspace rules. While civilian aviation regulatory agencies are welcoming the integration of more commercially operated UAS into civilian airspace, airports are responding to the growing number of incidents in recent years with counter measures to ensure drones do not interfere with regular operations. In the U.S., the Federal Aviation Authority (FAA) now receives more than 100 reports per month from pilots that have observed UAS operating near airports or within a restricted area of civilian airspace. The problem is a unique one for the FAA and other civilian aviation regulatory agencies who want to unleash as much commercial UAS innovation as possible within civilian airspace, but simultaneously recognize rogue operators are a problem. The FAA's method for addressing the operation of drones near
The goal of the automated mobility platforms (AMPs) initiative is to raise the bar of service regarding equity and sustainability for public mobility systems that are crucial to large facilities, and doing so using electrified, energy efficient technology. Using airports as an example, the rapid growth in air travel demand has led to facility expansions and congested terminals, which directly impacts equity (e.g., increased challenges for Passengers with Reduced Mobility [PRMs]) and sustainability—both of which are important metrics often overlooked during the engineering design process. Therefore, to evaluate systems and inform critical near- and long-term decisions more effectively, a holistic evaluation framework is proposed focused on four key areas: (1) mobility, with emphasis on travel time and accessibility within an airport, (2) environment, focused on energy consumption and greenhouse gas (GHG) emissions associated with intra-airport mobility, (3) equity, specifically to the
Young, StanleyGrahn, RickDuvall, Andrew
An extensive evaluation of the Deep Image Prior (DIP) technique for image inpainting on Synthetic Aperture Radar (SAR) images. Air Force Research Laboratory, Wright Patterson Air Force Base, OH Synthetic Aperture Radar (SAR) images are a powerful tool for studying the Earth's surface. They are radar signals generated by an imaging system mounted on a platform such as an aircraft or satellite. As the platform moves, the system emits sequentially high-power electromagnetic waves through its antenna. The waves are then reflected by the Earth's surface, re-captured by the antenna, and finally processed to create detailed images of the terrain below. SAR images are employed in a wide variety of applications. Indeed, as the waves hit different objects, their phase and amplitude are modified according to the objects' characteristics (e.g., permittivity, roughness, geometry, etc.). The collected signal provides highly detailed information about the shape and elevation of the Earth's surface
The upcoming regulations to achieve zero-emission passenger transport present challenges for designing new ferry powertrains. The proposed work investigates the feasibility of using a Proton Exchange Membrane Fuel Cell (PEMFC) power system to power a long-haul ferry. The paper describes the zero-order cell model as well as the method for estimating cell degradation. The stack modeling, heat balance equations, and auxiliary modeling are also presented. The proposed model enables the simulation of the fuel cell under different operating conditions and includes the use of air or oxygen as an oxidizer. A thermal management strategy for the overall PEMFC system is also proposed. The model was calibrated on the characteristic curves of the PEMFC Ballard FCvelocity™ HD6 (150 kW) and validated by reproducing experimental results. Then, a real load profile of a ferry, as well as the proposed powertrain is considered as case study. The presented results are related to a single daily mission and
Saponaro, GianmarcoStefanizzi, MicheleFranchini, EmanueleTorresi, MarcoCamporeale, Sergio
Electrification of public transport in cities puts lots of stress onto the vehicle's traction batteries and the power grid during charging. The authors present a self-learning operating strategy to improve the battery life and reduce stress on the power grid by lengthening charging operations as long as possible and avoiding extreme states of charge. During regular service operation, the operating strategy observes the vehicle state and energy flows inside of the vehicle and between vehicle and charging infrastructure. Based on these observations, the operating strategy plans a guidance state of charge trajectory for the trip and dispatches recommendations for charging and discharging the traction battery to the vehicle's ECU. Additionally, the operating strategy ensures reliable service trips by checking if the current state of charge matches the estimated energy consumption for a fixed range laying ahead. The operating strategy can detect and mitigate a situation in which the vehicle
von Kleist, HermannSaroch, LarsBeims, Martin
With the law on autonomous driving and the associated ordinance, it has been possible in Germany since June 2022 to grant operating permission to vehicles with automated driving function and to admit them to road traffic. For public transport, automated shuttle buses offer the opportunity to maintain the existing service despite a shortage of personnel and to close gaps in supply. The safety of vehicle occupants, other road users and third parties is a key concern in the operation of automated shuttle buses. As part of the project RABus “Real laboratory for automated bus operation in public transport in urban and rural areas”, which is funded by the Ministry of Transport Baden-Württemberg, the operational reliability of automated shuttle buses (SAE Level 4) in public transport is being scientifically investigated. In the implementation of automated driving, obstacle detection/avoidance is a safety-critical driving function. The number of possible scenarios in the real world is almost
Gao, KunWeinrich, UlrikeRiemer, ThomasReuss, Hans-Christian
One of the most significant challenges for the aviation industry in the winter is the deicing operations on runways. As a result, deicer chemicals can pollute the environment if used in a large amount. A mathematical model could help optimize the use of deicer chemicals. Road deicing models exist to predict pavement temperature covered by snow/ice during deicing operations. However, the specificity of airport operations requires a model for the runway deicing to simulate the mass of ice melted with usage of deicing agents. Here we propose a model for runway deicing and validate it against experimental results. Our model considers temperature, diffusive flux, and time changes in a normal direction. It also calculates the mass and heat transfer in three regions (liquid, mushy, and solid). We used the enthalpy method to determine the temperature and the interface location at each time step. In the liquid and solid, the deicer concentration is obtained by Fick’s law and updated at each
Maroufkhani, AidaCharpentier, ClaireMorency, FrancoisMomen, Gelareh
Measurements in snow conditions performed in the past were rarely initiated and best suited for pure and extremely detailed quantification of microphysical properties of a series of microphysical parameters, needed for accretion modelling. Within the European ICE GENESIS project, a considerable effort of natural snow measurements has been made during winter 2020/21. Instrumental means, both in-situ and remote sensing were deployed on the ATR-42 aircraft, as well as on the ground (ground station at ‘Les Eplatures’ airport in the Swiss Jura Mountains with ATR-42 overflights). Snow clouds and precipitation in the atmospheric column were sampled with the aircraft, whereas ground based and airborne radar systems allowed extending the observations of snow properties beyond the flight level chosen for the in situ measurements. Overall, five flight missions have been performed at different numerous flight levels (related temperature range from -10°C to +2°C) beyond the ‘Les Eplatures’ airport
Jaffeux, LouisSchwarzenboeck, AlfonsCoutris, PierreFebvre, GuyDezitter, FabienAguilar, Borisbillault-Roux, Anne-claireGrazioli, JacopoBerne, AlexisKöbschall, KilianJorquera, SusanaDelanoe, Julien
Surveillance cameras are becoming more commonplace in public environments, as well as finding use in private security and military operations. We are particularly interested in scenarios where a single pan-tilt-zoom (PTZ) camera is used to perform surveillance in large outdoor environments, which may include 360-degree horizontal coverage and depths out to 1 km or more. These scenarios exist in many environments such as security for building exteriors, airports, highways, parking lots, and property perimeters; anomaly detection in dense urban environments; and surveillance in military overwatch missions. In environments with many vertical obscurations (e.g., trees and buildings), ground-based cameras will need to be carefully located to provide long-range views. As the elevation of the camera is increased above the ground level, by placement on tall poles or building rooftops, for example, obtaining views of distant regions becomes easier.
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