https://hal.archives-ouvertes.fr/hal-01436218/document

Foliar heavy metal uptake, toxicity and detoxification in plants: A comparison of foliar and root metal uptake.

In this paper, we propose to use vehicular ad hoc networks (VANETs) to collect and aggregate real-time speed and position information on individual vehicles to optimize signal control at traffic intersections. We first formulate the vehicular traffic signal control problem as a job scheduling problem on processors, with jobs corresponding to platoons of vehicles. Under the assumption that all jobs are of equal size, we give an online algorithm, referred to as the oldest job first (OJF) algorithm, to minimize the delay across the intersection. We prove that the OJF algorithm is 2-competitive, implying that the delay is less than or equal to twice the delay of an optimal offline schedule with perfect knowledge of the arrivals. We then show how a VANET can be used to group vehicles into approximately equal-sized platoons, which can then be scheduled using OJF. We call this the two-phase approach, where we first group the vehicular traffic into platoons and then apply the OJF algorithm, i.e., the oldest arrival first (OAF) algorithm. Our simulation results show that, under light and medium traffic loads, the OAF algorithm reduces the delays experienced by vehicles as they pass through the intersection, as compared with vehicle-actuated methods, Webster's method, and pretimed signal control methods. Under heavy vehicular traffic load, the OAF algorithm performs the same as the vehicle-actuated traffic method but still produces lower delays, as when compared with Webster's method and the pretimed signal control method.

/pdf/adaptive-traffic-signal-control-with-vehicular-ad-hoc-5961aek8z8.pdf

Adaptive Traffic Signal Control With Vehicular Ad hoc Networks

Architecture and evaluation of a unified V2V and V2I communication system based on cellular networks

Covering the fundamental theory together with the state-of-the-art in research and development, this practical guide provides the techniques needed to design, analyze, and optimize device-to-device (D2D) communications in wireless networking. With an ever-increasing demand for higher data rate wireless access, D2D communication is set to become a key feature supported by next generation cellular networks. This book introduces D2D-based wireless communications from the physical, MAC, network, and application layer perspectives, providing all the key background information before moving on to discuss real-world applications as well as potential future developments. Key topics are discussed in detail, such as dynamic resource sharing (for example of spectrum and power) between cellular and ad hoc D2D communications to accommodate larger volumes of traffic and provide better service to users. Readers will understand the practical challenges of resource management, optimization, security, standardization, and network topology, and learn how the design principles are applied in practice.

Wireless Device-to-Device Communications and Networks

Recently, vehicular communication systems have attracted much attention, fueled largely by the growing interest in Intelligent Transportation Systems (ITS). These systems are aimed at addressing critical issues like passenger safety and traffic congestion, by integrating information and communication technologies into transportation infrastructure and vehicles. They are built on top of self organizing networks, known as a Vehicular Ad hoc Networks (VANET), composed of mobile vehicles connected by wireless links. While the solutions based on the traditional layered communication system architectures such as OSI model are readily applicable, they often fail to address the fundamental problems in ad hoc networks, such as dynamic changes in the network topology. Furthermore, many ITS applications impose stringent QoS requirements, which are not met by existing ad hoc networking solutions. The paradigm of cross-layer design has been introduced as an alternative to pure layered design to develop communication protocols. Cross-layer design allows information to be exchanged and shared across layer boundaries in order to enable efficient and robust protocols. There has been several research efforts that validated the importance of cross-layer design in vehicular networks. In this article, a survey of recent work on cross-layer communication solutions for VANETs is presented. Major approaches to cross-layer protocol design is introduced, followed by an overview of corresponding cross-layer protocols. Finally, open research problems in developing efficient cross-layer protocols for next generation transportation systems are discussed.

/pdf/a-survey-of-cross-layer-design-for-vanets-2tcnoeu33o.pdf

A survey of cross-layer design for VANETs

We propose VGrid: an ad hoc networking and computing grid formed by leveraging inter-vehicle wireless communications. In addition to exchanging data between vehicles, VGrid actively uses pertinent data to perform computations for solving traffic-related problems. In this paper, we examine the problem of smoothing vehicular traffic flow through the use of real-time position and velocity information exchanged over the network. This is accomplished through the application of 1) accident alert messages sent from the site of an accident or other obstruction in the road and 2) dynamically-calculated variable speed limits based on the local density of vehicles. Using a realistic model of highway traffic flow, we show through simulation that VGrid reduces speed variance, corresponding to more homogeneous vehicle behavior in freeflow and obstructed-lane scenarios

Smoothing Vehicular Traffic Flow Using Vehicular-Based Ad Hoc Networking & Computing Grid (VGrid)

Vehicular ad hoc networks (VANET) are characterized by high velocities and relatively uniform mobility of vehicles. As a result, the dynamics of VANET are different from generic mobile ad hoc networks. The behavior of vehicles and their effect on the protocol performance has not been comprehensively investigated in the context of VANET. In this work, we analyze the performance of multi-hop TCP in a multi-lane highway environment where vehicles are configured as clients or routers trying to reach a fixed access point. In particular, we look at the effect of tuning transmission power in dense and sparse road scenarios on the TCP throughput and latency. To conduct our study, we have developed an integrated simulation tool that accurately models both the vehicular mobility and the networking protocol stack. Using our simulation tool we obtain detailed TCP statistics and correlate them with the location, velocity, and other properties of VANET nodes. We study scenarios with a single sender as well as multiple senders. In each case, results show that throughput significantly deteriorates as the number of hops from the sender to the access point increases. A higher number of hops results in higher losses due to interference and loss of connectivity, which causes TCP to throttle back the sending rate unnecessarily

Impact of transmission power on TCP performance in vehicular ad hoc networks

With the availability of cheap and robust wireless devices there is demand for new applications in vehicular ad-hoc networks (VANET). The challenge in implementing applications is in understanding of the complex dynamics of highly mobile multi-hop ad hoc networks which is a characteristics of VANET. Studies have been reported that attempt to quantify transport protocol (TCP and UDP) performance in mobile ad-hoc network in general and VANet in particular. However, very little work has been done in looking at the effect of tuning transmission power and its effect on the performance of the transport layer protocols. Our work specifically looks at the result of tuning transmission power and its effect on UDP throughput in VANet. To facilitate this study we first developed a comprehensive integrated simulation tool which accurately simulates both vehicular mobility patterns and wireless network environment and the communication protocols; the former is based on a cellular automata model while the later is developed using JIST/SWANS network simulator. Results show that the major mitigating factor in VANETs multi-hop environment is the number of hops between the source and the destination. Increasing the transmission range results in decreasing the number of hops between source and destination effectively increasing throughput. However, increasing the transmission range beyond a certain point saturates the throughput due to increased interference. We also found that the effect of vehicle densities is only important at lower transmission ranges to provide the required connectivity.

Impact of Transmission Power on the Performance of UDP in Vehicular Ad Hoc Networks

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

A. Chen

Author Tools

Chat about Author

Papers

Smoothing Vehicular Traffic Flow Using Vehicular-Based Ad Hoc Networking & Computing Grid (VGrid)

Impact of transmission power on TCP performance in vehicular ad hoc networks

Impact of Transmission Power on the Performance of UDP in Vehicular Ad Hoc Networks