230 research outputs found

    Smart City Development with Urban Transfer Learning

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    Nowadays, the smart city development levels of different cities are still unbalanced. For a large number of cities which just started development, the governments will face a critical cold-start problem: 'how to develop a new smart city service with limited data?'. To address this problem, transfer learning can be leveraged to accelerate the smart city development, which we term the urban transfer learning paradigm. This article investigates the common process of urban transfer learning, aiming to provide city planners and relevant practitioners with guidelines on how to apply this novel learning paradigm. Our guidelines include common transfer strategies to take, general steps to follow, and case studies in public safety, transportation management, etc. We also summarize a few research opportunities and expect this article can attract more researchers to study urban transfer learning

    Connected vehicles for internet access: deployment and spectrum policies

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    Internet traffic from mobile users has been growing sharply. To meet the needs of thoseusers, it is important to expand capacity of networks that provide Internet access in cost effectiveways. This capacity has traditionally been provided by cellular networks. However,expanding the capacity of those networks alone may not be the most cost-effective way to meetthe present and future growth of mobile Internet under some circumstances. In this dissertation,we show that networks of connected vehicles can be an important way to complement thecapacity of cellular networks to provide mobile Internet access under several scenarios.Connected vehicles may soon be widely deployed, forming mesh networks of short-rangeconnections among vehicles and between vehicles and roadside infrastructure. Theseconnections are collectively referred to as vehicle-to-everything, or V2X. Deployment ofconnected vehicles and infrastructure is primarily intended to enhance road safety, and the U.S.Department of Transportation has recently proposed a mandate of V2X devices in vehiclesusing Dedicated Short Range Communications (DSRC) technology. Other applications are alsoenvisioned that include Internet access in vehicles connecting to roadside infrastructure servingas gateways to the Internet.In this work, we find that V2X-based networks are more cost-effective than cellular toprovide Internet access, in scenarios which DSRC devices are mandated in vehicles to enhanceroad safety. This is true initially for densely populated urban areas, but over time V2X-basednetworks would be cost-effective in less populated areas as well, as long as Internet traffic orpenetration of V2X devices grow as expected.Local and state governments are expected to deploy roadside infrastructure for safetyapplications. If that infrastructure is shared with Internet Service Providers for a fee, then V2XABSTRACT based networks are cost-effective in locations with even lower population densities than thelocations where it is cost-effective to deploy infrastructure for Internet access only. Moreover,the sharing fee could help governments save in infrastructure costs. We find the pricingstrategies that maximize either cost-effectiveness or government savings. We estimate thatgovernments could save about one-fifth of the total cost to deploy safety infrastructurenationwide in the U.S., if fees are set to maximize government savings. Although we find thatthese prices may differ from the pricing strategy that maximizes cost-effectiveness, maximizinggovernment savings results in near-optimal cost-effectiveness.The U.S. Federal Communications Commission has allocated 75 MHz of spectrum to beused exclusively by DSRC devices, and it has been hotly debated whether all or part of thatbandwidth should be shared with unlicensed devices. We find that it is highly efficient to shareany spectrum allocated to V2X communications beyond the portion of that spectrum that isneeded for safety-critical DSRC messages. V2X and unlicensed devices require up to 50% lessbandwidth on shared spectrum to achieve given throughputs, compared to V2X and unlicenseddevices using separate bands. We conclude that the spectrum available for V2X should bemaintained or increased, as long as much of that spectrum is shared with non-V2X devices.Conclusions are derived from an engineering-economic approach, in which part of theassumptions are based on data from a citywide deployment of connected vehicles in Portugal.The data is used in a detailed and realistic packet-level simulation model of V2X-basednetworks used to provide Internet access with DSRC technology. In some scenarios, thesimulation also includes unlicensed devices using Wi-Fi technology. The results of the networksimulation are then fed into engineering-economic models to compare costs of V2X-basednetworks with costs of macrocellular networks to carry given amounts of Internet traffic, and toestimate other measures such as government revenues and spectrum usage. Those measureshelp inform decisions about where and when to deploy V2X-based networks, decisions about whether and how to promote public-private partnerships to deploy V2X infrastructure, anddecisions about sharing spectrum used for V2X communications with non-V2X devices. <br

    6G Non-Terrestrial Networks Enabled Low-Altitude Economy: Opportunities and Challenges

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    The unprecedented development of non-terrestrial networks (NTN) utilizes the low-altitude airspace for commercial and social flying activities. The integration of NTN and terres- trial networks leads to the emergence of low-altitude economy (LAE). A series of LAE application scenarios are enabled by the sensing, communication, and transportation functionalities of the aircrafts. The prerequisite technologies supporting LAE are introduced in this paper, including the network coverage and aircrafts detection. The LAE functionalities assisted by aircrafts with respect to sensing and communication are then summarized, including the terrestrial and non-terrestrial targets sensing, ubiquitous coverage, relaying, and traffic offloading. Finally, several future directions are identified, including aircrafts collaboration, energy efficiency, and artificial intelligence enabled LAE.Comment: This paper has been submitted to IEEE for possible publicatio

    A Review on Energy, Environmental, and Sustainability Implications of Connected and Automated Vehicles

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    Connected and automated vehicles (CAVs) are poised to reshape transportation and mobility by replacing humans as the driver and service provider. While the primary stated motivation for vehicle automation is to improve safety and convenience of road mobility, this transformation also provides a valuable opportunity to improve vehicle energy efficiency and reduce emissions in the transportation sector. Progress in vehicle efficiency and functionality, however, does not necessarily translate to net positive environmental outcomes. Here, we examine the interactions between CAV technology and the environment at four levels of increasing complexity: vehicle, transportation system, urban system, and society. We find that environmental impacts come from CAV-facilitated transformations at all four levels, rather than from CAV technology directly. We anticipate net positive environmental impacts at the vehicle, transportation system, and urban system levels, but expect greater vehicle utilization and shifts in travel patterns at the society level to offset some of these benefits. Focusing on the vehicle-level improvements associated with CAV technology is likely to yield excessively optimistic estimates of environmental benefits. Future research and policy efforts should strive to clarify the extent and possible synergetic effects from a systems level to envisage and address concerns regarding the short- and long-term sustainable adoption of CAV technology.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149443/1/EEICAV_Taiebat et al (2018)_Environmental Science & Technology.pdfDescription of EEICAV_Taiebat et al (2018)_Environmental Science & Technology.pdf : Main articl

    Vehicular Ad Hoc Networks: Growth and Survey for Three Layers

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    A vehicular ad hoc network (VANET) is a mobile ad hoc network that allows wireless communication between vehicles, as well as between vehicles and roadside equipment. Communication between vehicles promotes safety and reliability, and can be a source of entertainment. We investigated the historical development, characteristics, and application fields of VANET and briefly introduced them in this study. Advantages and disadvantages were discussed based on our analysis and comparison of various classes of MAC and routing protocols applied to VANET. Ideas and breakthrough directions for inter-vehicle communication designs were proposed based on the characteristics of VANET. This article also illustrates physical, MAC, and network layer in details which represent the three layers of VANET. The main works of the active research institute on VANET were introduced to help researchers track related advanced research achievements on the subject

    Mobility and Accessibility in Urban Areas : An Assessment of Urban Transport and Social Exclusion among Low-Income Groups in Harare

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    This study sought to unravel and explain the transport related challenges faced by low-income residents of Southlea Park in Harare, Zimbabwe, and the resultant social exclusion that these residents were facing. The study was therefore inspired by the common struggles, hurdles and challenges faced by the Southlea Park residents in their commuting life. A single case study research design focusing on the residents of Southlea Park was adopted for the research. The study was, therefore, qualitative. Key informants from the relevant line ministries and transport parastatals, including the Zimbabwe United Passenger Company, the National Railways of Zimbabwe, the Vehicle Inspection Department, and the City of Harare (CoH) were taken as the research participants. From the private sector, key informants from commuter omnibus (kombis) operators, private bus operators and the unregistered taxicab (Mushikashika) were also taken as study participants as these were key players in the provision of transport to residents of Southlea Park. Semi-structured interviews and non-participant observation were the main data collection techniques. This study revealed that the residents of Southlea Park in Harare were being socially excluded and marginalized from economic and social participation due to the numerous transport related challenges they were facing. These challenges emanated from the misuse of land and corruption in the suburb that led to the spaces meant for business activities, schools and hospitals being taken up by houses hence forcing the residents to look for these services elsewhere. The players in the provision of public transport in the city were also significantly contributing to the transport related challenges faced by residents as they themselves were failing to cope with the levels of congestion, transport shortages, lawlessness on the part of the transport providers and the commuters themselves, and the heightened transport related corruption bedeviling the city. This study had a lot of policy implications for the players in the provision of transport to this suburb, including the need for a transport strategy and an overall integrated policy and master plan for further development of Southlea Park and other residential areas in the city’s fringesDissertation (MSocSci (Development Studies))--University of Pretoria, 2020.Anthropology and ArchaeologyMSocSci (Development Studies)Unrestricte

    Iot-enabled smart cities: evolution and outlook

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    For the last decade the Smart City concept has been under development, fostered by the growing urbanization of the world’s population and the need to handle the challenges that such a scenario raises. During this time many Smart City projects have been executed–some as proof-of-concept, but a growing number resulting in permanent, production-level deployments, improving the operation of the city and the quality of life of its citizens. Thus, Smart Cities are still a highly relevant paradigm which needs further development before it reaches its full potential and provides robust and resilient solutions. In this paper, the focus is set on the Internet of Things (IoT) as an enabling technology for the Smart City. In this sense, the paper reviews the current landscape of IoT-enabled Smart Cities, surveying relevant experiences and city initiatives that have embedded IoT within their city services and how they have generated an impact. The paper discusses the key technologies that have been developed and how they are contributing to the realization of the Smart City. Moreover, it presents some challenges that remain open ahead of us and which are the initiatives and technologies that are under development to tackle them.This research was partially funded by Spain State Research Agency (AEI) by means of the project FIERCE: Future Internet Enabled Resilient CitiEs (RTI2018-093475-A-I00). Prof. Song was supported by Smart City R&D project of the Korea Agency for Infrastructure Technology Advancement (KAIA) grant funded by the Ministry of Land, Infrastructure and Transport (MOLIT), Ministry of Science and ICT (MSIT) (Grant 18NSPS-B149386-01)
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