75 research outputs found
Synergizing Roadway Infrastructure Investment with Digital Infrastructure for Infrastructure-Based Connected Vehicle Applications: Review of Current Status and Future Directions
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The safety, mobility, environmental and economic benefits of Connected and Autonomous Vehicles (CAVs) are potentially dramatic. However, realization of these benefits largely hinges on the timely upgrading of the existing transportation system. CAVs must be enabled to send and receive data to and from other vehicles and drivers (V2V communication) and to and from infrastructure (V2I communication). Further, infrastructure and the transportation agencies that manage it must be able to collect, process, distribute and archive these data quickly, reliably, and securely. This paper focuses on current digital roadway infrastructure initiatives and highlights the importance of including digital infrastructure investment alongside more traditional infrastructure investment to keep up with the auto industry's push towards this real time communication and data processing capability. Agencies responsible for transportation infrastructure construction and management must collaborate, establishing national and international platforms to guide the planning, deployment and management of digital infrastructure in their jurisdictions. This will help create standardized interoperable national and international systems so that CAV technology is not deployed in a haphazard and uncoordinated manner
Development and Performance Evaluation of a Connected Vehicle Application Development Platform (CVDeP)
Connected vehicle (CV) application developers need a development platform to build,
test and debug real-world CV applications, such as safety, mobility, and environmental
applications, in edge-centric cyber-physical systems. Our study objective is to develop
and evaluate a scalable and secure CV application development platform (CVDeP)
that enables application developers to build, test and debug CV applications in realtime.
CVDeP ensures that the functional requirements of the CV applications meet the
corresponding requirements imposed by the specific applications. We evaluated the
efficacy of CVDeP using two CV applications (one safety and one mobility application)
and validated them through a field experiment at the Clemson University Connected
Vehicle Testbed (CU-CVT). Analyses prove the efficacy of CVDeP, which satisfies the
functional requirements (i.e., latency and throughput) of a CV application while
maintaining scalability and security of the platform and applications
Road pollution estimation using static cameras and neural networks
Este artículo presenta una metodología para estimar la contaminación en carreteras mediante el análisis de secuencias de video de tráfico. El objetivo es aprovechar la gran red de cámaras IP existente en el sistema de carreteras de cualquier estado o país para estimar la contaminación en cada área. Esta propuesta utiliza redes neuronales de aprendizaje profundo para la detección de objetos, y un modelo de estimación de contaminación basado en la frecuencia de vehículos y su velocidad. Los experimentos muestran prometedores resultados que sugieren que el sistema se puede usar en solitario o combinado con los sistemas existentes para medir la contaminación en carreteras.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
An Optimised BERT Pretraining Approach for Identification of Targeted Offensive Language: Data Imbalance and Potential Solutions
Targeted offensive comments and hate speech on online media platforms are on the rise, with evidential mental health consequences including suicide. Several NLP techniques have been proposed and in use. However, data imbalance in the training dataset is stopping them from performing at full potential. Solutions include under-sampling of the majority class, oversampling of the minority class or introducing synthetic samples. These approaches present with their own unique problems - that of critical information loss, overfitting and non-generalised models. The presented research explores these approaches for addressing the data imbalance problem, by varying the under/over/synthetic sampling rate and studying the performance as well as the generalisability of the models
Improved Flow Recovery from Packet Data
Typical event datasets such as those used in network intrusion detection comprise hundreds of thousands, sometimes millions, of discrete packet events. These datasets tend to be high dimensional, stateful, and time-series in nature, holding complex local and temporal feature associations. Packet data can be abstracted into lower dimensional summary data, such as packet flow records, where some of the temporal complexities of packet data can be mitigated, and smaller well-engineered feature subsets can be created. This data can be invaluable as training data for machine learning and cyber threat detection techniques. Data can be collected in real-time, or from historical packet trace archives. In this paper we focus on how flow records and summary metadata can be extracted from packet data with high accuracy and robustness. We identify limitations in current methods, how they may impact datasets, and how these flaws may impact learning models. Finally, we propose methods to improve the state of the art and introduce proof of concept tools to support this work
Bringing a CURE into a Discrete Mathematics Course and Beyond
Course-based Undergraduate Research Experiences (CUREs) have been well developed in the hard sciences, but math CUREs are all but absent from the literature. Like biology and chemistry, math programs suffer from a lack of research experiences and many students are not able to participate in programs like REUs (Research Experiences for Undergraduates). CUREs are a great alternative, but the current definition of CURE (see [1]) has potential barriers when applied to mathematics (e.g. time, novelty of project). Our solution to these barriers was to develop a math CURE pathway in which students complete Math CUREs in targeted courses. After finishing the pathway (or part of the pathway), students complete a research project in at least one of the following areas: Lie theory, representation theory, or combinatorics. The focus of this paper is the math CURE implemented in a discrete mathematics course for math and computer science majors. We share our experiences with the development and implementation of this CURE over several iterations as well as the impact of the CURE on students experiences through participant survey data obtained from this CURE
Characterising Payload Entropy in Packet Flows
Accurate and timely detection of cyber threats is critical to keeping our
online economy and data safe. A key technique in early detection is the
classification of unusual patterns of network behaviour, often hidden as
low-frequency events within complex time-series packet flows. One of the ways
in which such anomalies can be detected is to analyse the information entropy
of the payload within individual packets, since changes in entropy can often
indicate suspicious activity - such as whether session encryption has been
compromised, or whether a plaintext channel has been co-opted as a covert
channel. To decide whether activity is anomalous we need to compare real-time
entropy values with baseline values, and while the analysis of entropy in
packet data is not particularly new, to the best of our knowledge there are no
published baselines for payload entropy across common network services. We
offer two contributions: 1) We analyse several large packet datasets to
establish baseline payload information entropy values for common network
services, 2) We describe an efficient method for engineering entropy metrics
when performing flow recovery from live or offline packet data, which can be
expressed within feature subsets for subsequent analysis and machine learning
applications.Comment: 14 pages, 8 figure
New fermionic formula for unrestricted Kostka polynomials
A new fermionic formula for the unrestricted Kostka polynomials of type
is presented. This formula is different from the one given by
Hatayama et al. and is valid for all crystal paths based on
Kirillov-Reshetihkin modules, not just for the symmetric and anti-symmetric
case. The fermionic formula can be interpreted in terms of a new set of
unrestricted rigged configurations. For the proof a statistics preserving
bijection from this new set of unrestricted rigged configurations to the set of
unrestricted crystal paths is given which generalizes a bijection of Kirillov
and Reshetikhin.Comment: 35 pages; reference adde
Consistent Online Backup in Transactional File Systems
The backup taken of a file system must be consistent, preserving data integrity across files in the file system. With file system sizes getting very large, and with demand for continuous access to data, backup has to be taken when the file system is active (is online). Arbitrarily taken online backup may result in an inconsistent backup copy. We propose a scheme referred to as mutual serializability to take a consistent backup of an active file system assuming that the file system supports transactions. The scheme extends the set of conflicting operations to include read-read conflicts, and it is shown that if the backup transaction is mutually serializable with every other transaction individually, a consistent backup copy is obtained. The user transactions continue to serialize within themselves using some standard concurrency control protocol such as Strict 2PL. We put our scheme into a formal framework to prove its correctness, and the formalization as well as the correctness proof are independent of the concurrency control protocol used to serialize user transactions. The scheme has been implemented and experiments show that consistent online backup is possible with reasonable overhead
Artificial neural network to determine dynamic effect in capillary pressure relationship for two-phase flow in porous media with micro-heterogeneities
Open access articleAn artificial neural network (ANN) is presented for computing a parameter of dynamic two-phase flow in porous media with water as wetting phase, namely, dynamic coefficient (τ), by considering micro-heterogeneity in porous media as a key parameter. τ quantifies the dependence of time derivative of water saturation on the capillary pressures and indicates the rates at which a two-phase flow system may reach flow equilibrium. Therefore, τ is of importance in the study of dynamic two-phase flow in porous media. An attempt has been made in this work to reduce computational and experimental effort by developing and applying an ANN which can predict the dynamic coefficient through the “learning” from available data. The data employed for testing and training the ANN have been obtained from computational flow physics-based studies. Six input parameters have been used for the training, performance testing and validation of the ANN which include water saturation, intensity of heterogeneity, average permeability depending on this intensity, fluid density ratio, fluid viscosity ratio and temperature. It is found that a 15 neuron, single hidden layer ANN can characterize the relationship between media heterogeneity and dynamic coefficient and it ensures a reliable prediction of the dynamic coefficient as a function of water saturation
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