Tesis: "Connected Environment"

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Feng, Yiheng. "Intelligent Traffic Control in a Connected Vehicle Environment". Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/578411.

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Signal control systems have experienced tremendous development both in hardware and in control strategies in the past 50 years since the advent of the first electronic traffic signal control device. The state-of-art real-time signal control strategies rely heavily on infrastructure-based sensors, including in-pavement or video based loop detectors for data collection. With the emergence of connected vehicle technology, mobility applications utilizing vehicle to infrastructure (V2I) communications enable the intersection to acquire a much more complete picture of the nearby vehicle states. Based on this new source of data, traffic controllers should be able to make "smarter" decisions. This dissertation investigates the traffic signal control strategies in a connected vehicle environment considering mobility as well as safety. A system architecture for connected vehicle based signal control applications under both a simulation environment and in the real world has been developed. The proposed architecture can be applied to applications such as adaptive signal control, signal priority including transit signal priority (TSP), freight signal priority (FSP), emergency vehicle preemption, and integration of adaptive signal control and signal priority. Within the framework, the trajectory awareness of connected vehicles component processes and stores the connected vehicle data from Basic Safety Message (BSM). A lane level intersection map that represents the geometric structure was developed. Combined with the map and vehicle information from BSMs, the connected vehicles can be located on the map. Some important questions specific to connected vehicle are addressed in this component. A geo-fencing area makes sure the roadside equipment (RSE) receives the BSM from only vehicles on the roadway and within the Dedicated Short-range Communications (DSRC) range. A mechanism to maintain anonymity of vehicle trajectories to ensure privacy is also developed. Vehicle data from the trajectory awareness of connected vehicles component can be used as the input to a real-time phase allocation algorithm that considers the mobility aspect of the intersection operations. The phase allocation algorithm applies a two-level optimization scheme based on the dual ring controller in which phase sequence and duration are optimized simultaneously. Two objective functions are considered: minimization of total vehicle delay and minimization of queue length. Due to the low penetration rate of the connected vehicles, an algorithm that estimates the states of unequipped vehicles based on connected vehicle data is developed to construct a complete arrival table for the phase allocation algorithm. A real-world intersection is modeled in VISSIM to validate the algorithms. Dangerous driving behaviors may occur if a vehicle is trapped in the dilemma zone which represents one safety aspect of signalized intersection operation. An analytical model for estimating the number of vehicles in dilemma zone (NVDZ) is developed on the basis of signal timing, arterial geometry, traffic demand, and driving characteristics. The analytical model of NVDZ calculation is integrated into the signal optimization to perform dilemma zone protection. Delay and NVDZ are formulated as a multi-objective optimization problem addressing efficiency and safety together. Examples show that delay and NVDZ are competing objectives and cannot be optimized simultaneously. An economic model is applied to find the minimum combined cost of the two objectives using a monetized objective function. In the connected vehicle environment, the NVDZ can be calculated from connected vehicle data and dilemma zone protection is integrated into the phase allocation algorithm. Due to the complex nature of traffic control systems, it is desirable to utilize traffic simulation in order to test and evaluate the effectiveness and safety of new models before implementing them in the field. Therefore, developing such a simulation platform is very important. This dissertation proposes a simulation environment that can be applied to different connected vehicle related signal control applications in VISSIM. Both hardware-in-the-loop (HIL) and software-in-the-loop (SIL) simulation are used. The simulation environment tries to mimic the real world complexity and follows the Society of Automotive Engineers (SAE) J2735 standard DSRC messaging so that models and algorithms tested in the simulation can be directly applied in the field with minimal modification. Comprehensive testing and evaluation of the proposed models are conducted in two simulation networks and one field intersection. Traffic signal priority is an operational strategy to apply special signal timings to reduce the delay of certain types of vehicles. The common way of serving signal priority is based on the "first come first serve" rule which may not be optimal in terms of total priority delay. A priority system that can serve multiple requests with different priority levels should perform better than the current method. Traditionally, coordination is treated in a different framework from signal priority. However, the objectives of coordination and signal priority are similar. In this dissertation, adaptive signal control, signal priority and coordination are integrated into a unified framework. The signal priority algorithm generates a feasible set of optimal signal schedules that minimize the priority delay. The phase allocation algorithm considers the set as additional constraints and tries to minimize the total regular vehicle delay within the set. Different test scenarios including coordination request, priority vehicle request and combination of coordination and priority requests are developed and tested.

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2

Tatakis, Thomas Jr. "NAMER : a distributed name server for a connected UNIX environment /". Online version of thesis, 1988. http://hdl.handle.net/1850/10448.

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3

Dabboussi, Abdallah. "Dependability approaches for mobile environment : Application on connected autonomous vehicles". Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCA029.

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Les véhicules autonomes et connectés (VAC) doivent avoir une exigence de fiabilité et de sécurité adéquate dans un environnement incertain aux circonstances complexes. La technologie des capteurs, les actionneurs et l'intelligence artificielle (IA) améliorent constamment leurs performances, ce qui permet un développement continu des véhicules autonomes et une automatisation accrue de la tâche de conduite. Les VAC présentent de nombreux avantages dans la vie humaine, tels que l’augmentation de la sécurité routière, la réduction de la pollution et la fourniture d’une mobilité autonome aux non-conducteurs. Cependant, ces composants avancés créent un nouvel ensemble de défis en matière de sécurité et de fiabilité. Il est donc nécessaire d’évaluer ces technologies avant leur mise en œuvre.Nous étudions dans cette thèse la fiabilité du VAC dans son ensemble, en nous concentrant sur les capteurs et le système de communication. Pour cela, une analyse fonctionnelle a été réalisée pour le système VAC. Notre approche scientifique pour l'analyse de la fiabilité du VAC a été structurée avec des méthodes combinant des approches quantitatives et qualitatives (telles que l'analyse fonctionnelle interne et externe, l'analyse préliminaire des risques (APR) et l'analyse des modes de défaillance, de leurs effets et de leur criticité (AMDEC), etc. Afin de prouver nos résultats, une simulation a été réalisée à l'aide de la probabilité d'analyse d'arbre de défaillance (ADD) et elle a été réalisée pour valider l'approche proposée. Les données (taux d'échec) utilisées proviennent d'une base de données professionnelle concernant le type de composants présentés dans le système. À partir de ces données, un modèle probabiliste de dégradation a été proposé. Le calcul de probabilité a été effectué par rapport à un moment d'utilisation de référence. Par la suite, une analyse de sensibilité a été suggérée concernant les paramètres de fiabilité et des propositions de restructuration ont été élaborées pour les composants.CAV fournit des services de communication entre véhicules : véhicules à véhicules (V2V) ou avec infrastructures côté rue : véhicules à infrastructures (V2I). La technologie des “Communications dédiées à courte portée” (DSRC = Dedicated Short Range Communications) utilise plusieurs canaux pour fournir une variété d'applications de sécurité. Les applications de sécurité nécessitent des transmissions appropriées et fiables, tandis que les applications non liées à la sécurité exigent des performances et une vitesse élevée. Aujourd’hui, la diffusion de messages de sécurité de base (Basic safety message, BSM) est l’un des services fondamentaux des véhicules connectés. Pour cela, un modèle analytique destiné à évaluer la fiabilité des services de diffusion V2V relatifs à la sécurité basée sur IEEE 802.11 dans le système DSRC sur autoroute a été proposé. Enfin, une amélioration du modèle proposé a été faite afin d'accroître la fiabilité de la connexion V2V, en tenant compte de nombreux facteurs tels que la portée de transmission, la densité du véhicule, la distance de sécurité sur l'autoroute, le taux d'erreur de paquets, l'influence de bruit et les taux de défaillants pour les équipements de communications.L'évaluation de ces problèmes conduit à une analyse de sensibilité liée aux paramètres de fiabilité, ce qui contribue à davantage d'innovation dans les domaines de l'ingénierie automobile
Connected and Autonomous vehicles (CAV) must have adequate reliability and safety requirements in uncertain environments with complex circumstances. Sensor technology, actuators and artificial intelligence (AI) are constantly and rapidly evolving, thus enabling further development of self-driving vehicles, and increasing the automation of driving. CAV shows many benefits in human life such as increasing road safety, reducing pollution, and providing independent mobility to non-drivers. However, these advanced components create a new set of challenges concerning safety and dependability. Hence, it is necessary to evaluate these technologies before implementation.We study in this thesis the reliability of CAV as a whole, focusing on sensors and the communication system. For that purpose, a functional analysis was done for the CAV system.Our scientific approach for the analyzing the CAV reliability, was structured with methods that combine quantitative and qualitative approaches such as functional analysis for both internal and external, Preliminary Risk Analysis (PRA), and failure modes and effects criticality analysis (FMECA), in addition to other analysis techniques.To prove our results, a simulation was done using the Fault Tree analysis (FTA) probability in order to validate the proposed approach. The data (Failure ratio) used were from a professional database related to the type of components presented in the system. Using this data, a probabilistic model of degradation was proposed. A probability calculation was performed in relation to a reference time of use. Thereafter a sensitivity analysis was suggested concerning the reliability parameters and redesign proposals developed for the components.CAV provide several communication models: vehicles to vehicle (V2V), or with Road Side Infrastructure: vehicle to infrastructure (V2I). Dedicated Short Range Communication (DSRC) employs a multichannel approach to cater for a variety of safety and non-safety applications. Safety applications necessitate appropriate and reliable transmissions, while non-safety applications require performance and high speed. Broadcasting of Basic Safety Messages (BSM) is one of the fundamental services in today’s connected vehicles. For that, an analytical model to evaluate the reliability of IEEE 802.11 based V2V safety-related broadcast services in DSRC system on highway was proposed. Finally, an enhancement on the proposed model was made in order to increase the reliability of the V2V connection, taking into consideration many factors such as transmission range, vehicle density, and safety headway distance on highway, packet error rate, noise influence, and failures rates of communication equipment.Evaluating these problems leads to a sensitivity analysis related to reliability parameters, which helps further innovation in CAV and automobile engineering

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Annam, Raja Bharat. "Synthetic Innovation to Complex Intersection Control: Intelligent Roundabout in Connected Vehicle Environment". University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1623169949508287.

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5

Khoshmagham, Shayan y Shayan Khoshmagham. "Real Time Performance Observation and Measurement in a Connected Vehicle Environment". Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/621582.

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Performance monitoring systems have experienced remarkable development in the past few decades. In today's world, an important issue for almost every industry is to find a way to appropriately evaluate the performance of the provided service. Having a reliable performance monitoring system is necessary, and researchers have developed assessment models and tools to deal with this concern. There are many approaches to the development of performance measurement and observation systems. The internet-of-things (IoT) creates a broad range of opportunities to monitor the systems by using the information from connected people and devices. The IoT is providing many new sources of data that need to be managed. One of the key issues that arises in any data management system is confidentiality and privacy.Significant progress has been made in development and deployment of performance monitoring systems in the signalized traffic environment. The current monitoring and data collection system relies mostly on infrastructure-based sensors, e.g. loop detectors, video surveillance, cell phone data, vehicle signatures, or radar. High installation and maintenance costs and a high rate of failure are the two major drawbacks of the existing system. Emerging technologies, i.e. connected vehicles (CV), will provide a new, high fidelity approach to be used for better performance monitoring and traffic control.This dissertation investigates the real-time performance observation system in a multi-modal connected vehicle environment. A trajectory awareness component receive and processes the connected vehicle data using the Basic Safety Message (BSM). A geo-fence section makes sure the infrastructure system (for example, roadside unit (RSU)) receives the BSM from only the connected vehicles on the roadway and within the communication range. The processed data can be used as an input to a real-time performance observer component.Three major classes of performance metrics, including mobility, signal, and CV-system measures, are investigated. Multi-modal dashboards that utilize radar diagrams are introduced to visualize large data sets in an easy to understand way. A mechanism to maintain the anonymity of vehicle information to ensure privacy was also developed. The proposed algorithm uses partial vehicle trajectories to estimate travel time average and variability on a link basis. It is shown that the model is not very sensitive to the market penetration rate of connected vehicles. This is a desirable feature especially because of the fact that the market penetration rate of connected vehicles will not be very high in near future. The system architecture for connected vehicle based performance observation applications was developed to be applicable for both a simulation environment and a real world traffic system. Both hardware-in-the-loop (HIL) and software-in-the-loop (SIL) simulation environments are developed and calibrated to mimic the real world. Comprehensive testing and assessment of the proposed models and algorithms are conducted in simulation as well as field test networks. A web application is also developed as part of a central system component to generate reports and visualizations of the data collection experiments.

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6

Liu, Yan. "Highway Capacity and Traffic Behavior under Connected and Automated Traffic Environment". University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1627667986751621.

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7

Lause, Federico Valentin III. "Adapting Crash Modification Factors for the Connected and Autonomous Vehicle Environment". UKnowledge, 2019. https://uknowledge.uky.edu/ce_etds/90.

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The Crash Modification Factor (CMF) clearinghouse can be used to estimate benefits for specific highway safety countermeasures. It assists safety professionals in the allocation of investments. The clearinghouse contains over 7000 entries of which only 446 are categorized as intelligent transportation systems or advanced technology, but none directly address connected or autonomous vehicles (CAVs). Further, the effectiveness of highway safety countermeasures is assumed to remain constant over time, an assumption that is particularly problematic as new technologies are introduced. For example, for the existing fleet of human-driven vehicles, installation of rumble strip can potentially reduce “run-off-road” crashes by 40%. If specific CAV technologies, e.g., lane-tracking, can work without rumble strips, and say, half of all cars are so equipped, only half of the fleet will benefit, reducing the benefits of rumble strips by a commensurate amount. Benefits of the two improvements, e.g., rumble strips and automated vehicles, should not be double-counted. As there will still be human-driven and/or non-connected vehicles in the fleet, conventional countermeasures are still necessary, although returns on conventional safety investments may be significantly overestimated. This is important as safety investments should be optimized and geared to future, not past fleets. Moreover, as CMFs are based on historical events, the types of crashes experienced by human-driven, un-connected cars are likely to be much different in the future. This research presents methods to estimate the safety benefits that autonomous vehicles have to offer and the changes needed in CMFs as a result of their adoption. This will primarily be achieved by modifying and enhancing a tool co-developed by the Fellow that estimates the safety benefits of different levels of autonomy. This tool, ddSAFCAT, estimates CAV safety benefits using real-world data for crashes, market penetration, and effectiveness.

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8

Harper, Corey David. "Transitioning to a Connected and Automated Vehicle Environment: Opportunities for Improving Transportation". Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/1007.

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Over the past few years automotive and technology companies have made significant advances in what has been traditionally a completely human function: driving. Crash avoidance features such as lane departure warning and forward collision warning are becoming increasingly more common and cheaper to obtain, even on non-luxury vehicles. Technology companies and auto manufacturers have announced plans to have self-driving vehicles ready for public use as early as 2020. The mass adoption of automated vehicles (AVs) could significantly change surface transportation as we know it today. This thesis is intended to provide a technical analysis of the potential impacts of AVs on current light-duty vehicle miles traveled (VMT) and parking decisions, the economic desirability of widespread deployment of partially automated technologies, and methods for existing roadways to transition to connected and automated vehicle (CAV) transportation, so that policymakers can make more informed decisions during the transition to CAVs. This work takes a look at AVs from a point in time where vehicles are equipped with driver assistance systems (Level 1) to a point in time where AVs are driverless (Level 5) and can self-park. The results of this work indicate that the fleet-wide adoption of partially automated crash avoidance technologies could provide net-benefit of about $4 billion at current system effectiveness and could provide an annual net-benefit up to $202 billion if all relevant crashes could be prevented. About 25% of all crashes could be addressed by the crash avoidance technologies examined in this dissertation. Over time, as technologies become more effective and cheaper due to economies of scale, greater benefits than the $4 billion could be realized. As automated technologies become more advanced and widespread, existing roadways will need to be able to accommodate these vehicles. This work investigates the effects of a dedicated truck platoon lane on congestion on the Pennsylvania Turnpike and provides a method for existing roadways and highways to determine viable platoon demonstration sites. The initial results suggest that there are several sections of turnpike that could serve as commercial truck platoon demonstration site while still providing a high LOS to all other vehicles. Once AVs can safely and legally drive unoccupied, vehicles will no longer be limited to their driver’s destination and can search for cheaper parking in more distant parking locations. This work simulates a fleet of privately owned vehicles (POVs) in search of cheaper parking in Seattle, using a rectangular grid throughout the study area. Model results indicate that we are not likely to see significant increase in vehicle miles traveled (VMT) and energy use from cars moving from downtown parking lots to cheaper parking in distance locations but at higher penetration rates, parking lot revenues could likely decline to the point where operating a lot is unsustainable economically, if no parking demand management policies are implemented. Driverless vehicles also promise to increase mobility for those in underserved populations. This work estimates bounds on the potential increases in travel in a fully automated vehicle environment due to an increase in mobility from the non-driving and senior populations and people with travel-restrictive medical conditions. Three demand wedges were established in order to conduct a first-order bounding analysis. The combination of the results from all three demand wedges represents an upper bound of 295 billion miles or a 14% increase in annual light-duty VMT for the US population 19 and older. AV technology holds much promise in providing a more accessible and safe transportation system. This thesis can help policymakers and stakeholders maximize the benefits and minimize the challenges.

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Khosravi, Sara y Sara Khosravi. "Location-Based System to Improve Pedestrian Safety in a Connected Vehicle Technology Environment". Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/626306.

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People with vision impairment have various challenges in wayfinding, navigation, and crossing signalized intersections. They often face physical and information barriers that impede their mobility and undermine their safety along a trip. Visually impaired people usually use a white cane as their primary aid when crossing urban traffic intersections. In order to improve their mobility, safety and accessibility, it is important to provide an assistive system to help them in intersection navigation and to provide information regarding the surrounding environment. While assistive systems have been developed to help visually impaired pedestrians to navigate and find their way, using these systems may be inconvenient. Furthermore, none of the currently available systems provide communication between the users and traffic signal controller that can help them request pedestrian crossing signal timing. Emerging connected vehicle technologies can provide a solution to assist visually impaired people and address their challenges. Conflicts between vehicles and vulnerable road users (VRUs) often result in injuries and fatalities. A situational awareness system could be based on wireless communications between vehicles and VRUs for the exchange of situational awareness information. Compared to the radar-based and vision-based systems, the wireless-based system. can improve VRUs’ safety, especially in non-line-of-sight (NLOS) situations. In particular, it can be very helpful when drivers are making a right or left turn where there is a pedestrian in a crosswalk and visibility conditions are poor. The Smart Walk Assistant (SWA) system was designed, developed, and tested during the research of this dissertation. It includes two wireless communication pathways; pedestrian-to-infrastructure (P2I) and pedestrian-to-vehicle (P2V). The first communication pathway enables users to send a pedestrian signal request to the traffic signal controller and receive traffic signal status. The second communication pathway enables pedestrians and vehicles to exchange information, including location, speed, and heading, that can be used to detect possible conflict between pedestrian and vehicles and provide conflict alerts. The SWA system may be especially beneficial to pedestrians with disability (e.g., blind or visually impaired pedestrians) who would benefit from active support to safely cross streets at signalized intersections. Developing a reliable situational awareness system for pedestrians is much more challenging than for vehicles because a vehicle’s movement is more predictable and usually remains in the lane in the road. In order to provide better location-based services for pedestrians, a position accuracy is needed of, at most, the width of a crosswalk or sidewalk. The SWA system includes a method to estimate a pedestrian’s position. The algorithm is based on integrating Map-Matching and an Extended Kalman Filter (EKF) in a connected vehicle environment to provide precise location information. The system architecture for the SWA application was developed to be applicable for both a simulation environment and a real world traffic system. Hardware-in-the-loop (HIL) simulation environment is developed and calibrated to mimic the real world. Comprehensive testing and assessment of the system and algorithms are conducted in simulation as well as field test networks.

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10

Beak, Byungho y Byungho Beak. "Systematic Analysis and Integrated Optimization of Traffic Signal Control Systems in a Connected Vehicle Environment". Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/626304.

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Traffic signal control systems have been tremendously improved since the first colored traffic signal light was installed in London in December 1868. There are many different types of traffic signal control systems that can be categorized into three major control types: fixed-time, actuated, and adaptive. Choosing a proper traffic signal system is very important since there exists no perfect signal control strategy that fits every traffic network. One example is traffic signal coordination, which is the most widely used traffic signal control system. It is believed that performance measures, such as travel times, vehicle delay, and number of stops, can be enhanced by synchronizing traffic signals over a corridor. However, it is not always true that the coordination will have the same benefits for all the traffic in the network. Most of the research on coordination has focused only on strengthening the major movement along the coordinated routes without considering system-wide impacts on other traffic. Therefore, before implementing a signal control system to a specific traffic network, a thorough investigation should be conducted to see how the control strategy may impact the entire network in terms of the objectives of each type of traffic control system. This dissertation first considers two different kinds of systematic performance analyses for traffic signal control systems. Then, it presents two types of signal control strategies that account for current issues in coordination and priority control systems, respectively. First, quantitative analysis of smooth progression for traffic flow is investigated using connected vehicle technology. Many studies have been conducted to measure the quality of progression, but none has directly considered smooth progression as the significant factor of coordination, despite the fact that the definition of coordination states that the goal is to have smooth traffic flow. None of the existing studies concentrated on measuring a continuous smooth driving pattern for each vehicle in terms of speed. In order to quantify the smoothness, this dissertation conducts an analysis of the speed variation of vehicles traveling along a corridor. A new measure is introduced and evaluated for different kinds of traffic control systems. The measure can be used to evaluate how smoothly vehicles flow along a corridor based on the frequency content of vehicle speed. To better understand the impact of vehicle mode, a multi-modal analysis is conducted using the new measure. Second, a multi-modal system-wide evaluation of traffic signal systems is conducted. This analysis is performed for traffic signal coordination, which is compared with fully actuated control in terms of a systematic assessment. Many optimization models for coordination focus mainly on the objective of the coordinated route and do not account for the impacts on side street movements or other system-wide impacts. In addition, multi-modality is not considered in most optimized coordination plans. Thus, a systematic investigation of traffic signal coordination is conducted to analyze the benefits and impacts on the entire system. The vehicle time spent in the system is measured as the basis of the analysis. The first analysis evaluates the effect of coordination on each route based on a single vehicle mode (regular passenger vehicles). The second analysis reveals that how multi-modality affects the performance of the entire system. Third, in order to address traffic demand fluctuation and traffic pattern changes during coordination periods, this dissertation presents an adaptive optimization algorithm that integrates coordination with adaptive signal control using data from connected vehicles. Through the algorithm, the coordination plan can be updated to accommodate the traffic demand variation and remain optimal over the coordination period. The optimization framework consists of two levels: intersection and corridor. The intersection level handles phase allocation in real time based on connected vehicle trajectory data, while the corridor level deals with the offsets optimization. The corridor level optimization focuses on the performance of the vehicle movement along the coordinated phase, while at the intersection level, all movements are considered to create the optimal signal plan. The two levels of optimizations apply different objective functions and modeling methodologies. The objective function at the intersection level is to minimize individual vehicle delay for both coordinated and non-coordinated phases using dynamic programming (DP). At the corridor level, a mixed integer linear programming (MILP) is formulated to minimize platoon delay for the coordinated phase. Lastly, a peer priority control strategy, which is a methodology that enhances the multi modal intelligent traffic signal system (MMITSS) priority control model, is presented based on peer-to-peer (P2P) and dedicated short range communication (DSRC) in a connected vehicle environment. The peer priority control strategy makes it possible for a signal controller to have a flexible long-term plan for prioritized vehicles. They can benefit from the long-term plan within a secured flexible region and it can prevent the near-term priority actions from having a negative impact on other traffic by providing more flexibility for phase actuation. The strategy can be applied to all different modes of vehicles such as transit, freight, and emergency vehicles. Consideration for far side bus stops is included for transit vehicles. The research that is presented in this dissertation is constructed based on Standard DSRC messages from connected vehicles such as Basic Safety Messages (BSMs), Signal Phasing and Timing Messages (SPaTs), Signal Request Messages (SRMs), and MAP Messages, defined by Society of Automotive Engineers (SAE) (SAE International 2016).

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11

Murray, Alexander R. "The New Normal: Lived Experiences of Teachers’ Educating Students in an Always-on and Connected Middle School Environment". Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1458314482.

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Hannoun, Gaby Joe. "Framework for better Routing Assistance for Road Users exposed to Flooding in a Connected Vehicle Environment". Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/79911.

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Flooding can severely disrupt transportation systems. When safety measures are limited to road closures, vehicles affected by the flooding have an origin, destination, or path segment that is closed or soon-to-be flooded during the trip's duration. This thesis introduces a framework to provide routing assistance and trip cancellation recommendations to affected vehicles. The framework relies on the connected vehicle environment for real-time link performance measures and flood data and evaluates the trip of the vehicle to determine whether it is affected by the flood or not. If the vehicle is affected and can still leave its origin, the framework generates the corresponding routing assistance in the form of hyperpath(s) or set of alternative paths. On the other hand, a vehicle with a closed origin receives a warning to wait at origin, while a vehicle with an affected destination is assigned to a new safe one. This framework is tested on two transportation networks. The evaluation of the framework's scalability to different network sizes and the sensitivity of the results to various flood characteristics, policy-related variables and other dependencies are performed using simulated vehicle data and hypothetical flood scenarios. The computation times depends on the network size and flood depth but have generally an average of 1.47 seconds for the largest tested network and deepest tested flood. The framework has the potential to alleviate the impacts and inconveniences associated with flooding.
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13

Zamanipour, Mehdi y Mehdi Zamanipour. "A Unified Decision Framework for Multi-Modal Traffic Signal Control Optimization in a Connected Vehicle Environment". Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/620993.

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Motivated by recent advances in vehicle positioning and vehicle-to-infrastructure (V2I) communication, traffic signal controllers are able to make smarter decisions. Most of the current state-of-the-practice signal priority control systems aim to provide priority for only one mode or based on first-come-first-served logic. Consideration of priority control in a more general framework allows for several different modes of travelers to request priority at any time from any approach and for other traffic control operating principles, such as coordination, to be considered within an integrated signal timing framework. This leads to provision of priority to connected priority eligible vehicles with minimum negative impact on regular vehicles. This dissertation focuses on providing a real-time decision making framework for multi modal traffic signal control that considers several transportation modes in a unified framework using Connected Vehicle (CV) technologies. The unified framework is based on a systems architecture for CVs that is applicable in both simulated and real world (field) testing conditions. The system architecture is used to design both hardware-in-the-loop and software-in-the-loop CV simulation environment. A real-time priority control optimization model and an implementation algorithm are developed using priority eligible vehicles data. The optimization model is extended to include signal coordination concepts. As the penetration rate of the CVs increases, the ability to predict the queue more accurately increases. It is shown that accurate queue prediction improves the performance of the optimization model in reducing priority eligible vehicles delay. The model is generalized to consider regular CVs as well as priority vehicles and coordination priority requests in a unified mathematical model. It is shown than the model can react properly to the decision makers' modal preferences.

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14

Njobelo, Gwamaka Lameck. "A Microscopic Simulation Study of Applications of Signal Phasing and Timing Information in a Connected Vehicle Environment". UNF Digital Commons, 2018. https://digitalcommons.unf.edu/etd/786.

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The connected vehicle technology presents an innovative way of sharing information between vehicles and the transportation infrastructure through wireless communications. The technology can potentially solve safety, mobility, and environmental challenges that face the transportation sector. Signal phasing and timing information is one category of information that can be broadcasted through connected vehicle technology. This thesis presents an in-depth study of possible ways signal phasing and timing information can be beneficial as far as safety and mobility are concerned. In total, three studies describing this research are outlined. The first study presented herein focuses on data collection and calibration efforts of the simulation model that was used for the next two studies. The study demonstrated a genetic algorithm procedure for calibrating VISSIM discharge headways based on queue discharge headways measured in the field. Video data was used to first compute intersection discharge headways for individual vehicle queue position and then to develop statistical distributions of discharge headways for each vehicle position. Except for the 4th vehicle position, which was best fitted by the generalized extreme value (GEV) distribution, the Log-logistic distribution was observed to be the best fit distribution for the rest of vehicle positions. Starting with the default values, the VISSIM parameters responsible for determining discharge headways were heuristically adjusted to produce optimal values. The optimal solutions were achieved by minimizing the Root Mean Square Error (RMSE) between the simulated and observed data. Through calibration, for each vehicle position, it was possible to obtain the simulated headways that reflect the means of the observed field headways. However, calibration was unable to replicate the dispersion of the headways observed in the field mainly due to VISSIM limitations. Based on the findings of this study, future work on calibration in VISSIM that would account for the dispersion of mixed traffic flow characteristics is warranted. The second study addresses the potential of connected vehicles in improving safety at the vicinity of signalized intersections. Although traffic signals are installed to reduce the overall number of collisions at intersections, rear-end collisions are increased due to signalization. One dominant factor associated with rear-end crashes is the indecisiveness of the driver, especially in the dilemma zone. An advisory system to help the driver make the stop-or-pass decision would greatly improve intersection safety. This study proposed and evaluated an Advanced Stop Assist System (ASAS) at signalized intersections by using Infrastructure-to-Vehicle (I2V) and Vehicle-to-Vehicle (V2V) communication. The proposed system utilizes communication data, received from Roadside Unit (RSU), to provide drivers in approaching vehicles with vehicle-specific advisory speed messages to prevent vehicle hard-braking upon a yellow and red signal indication. A simulation test bed was modeled using VISSIM to evaluate the effectiveness of the proposed system. The results demonstrate that at full market penetration (100% saturation of vehicles equipped with on-board communication equipment), the proposed system reduces the number of hard-braking vehicles by nearly 50%. Sensitivity analyses of market penetration rates also show a degradation in safety conditions at penetration rates lower than 40%. The results suggest that at least 60% penetration rate is required for the proposed system to minimize rear-end collisions and improve safety at the signalized intersections. The last study addresses the fact that achieving smooth urban traffic flow requires reduction of excessive stop-and-go driving on urban arterials. Smooth traffic flow comes with several benefits including reduction of fuel consumption and emissions. Recently, more research efforts have been directed towards reduction of vehicle emissions. One such effort is the use of Green Light Optimal Speed Advisory (GLOSA) systems which use wireless communications to provide individual drivers with information on the approaching traffic signal phase and advisory speeds to arrive at the intersection on a green phase. Previously developed GLOSA algorithms do not address the impact of time to discharge queues formed at the intersection. Thus, this study investigated the influence of formed intersection queues on the performance of GLOSA systems. A simulation test-bed was modeled inside VISSIM to evaluate the algorithm’s effectiveness. Three simulation scenarios were designed; the baseline with no GLOSA in place, scenario 2 with GLOSA activated and queue discharge time not considered, and scenario 3 with GLOSA activated and where queue dissipation time was used to compute advisory speeds. At confidence level the results show a significant reduction in the time spent in queue when GLOSA is activated (scenarios 2 and 3). The change in the average number of stops along the corridor was found not to be significant when the base scenario was compared against scenario 2. However, a comparison between scenarios 2 and 3 demonstrates a significant reduction in the average number of stops along the corridor, and also in the time spent waiting in queues

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15

Hannoun, Gaby Joe. "Optimization of an Emergency Response Vehicle's Intra-Link Movement in Urban Transportation Networks Utilizing a Connected Vehicle Environment". Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/92591.

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Downstream vehicles detect an emergency response vehicle (ERV) through sirens and/or strobe lights. These traditional warning systems do not give any recommendation about how to react, leaving the drivers confused and often adopting unsafe behavior while trying to open a passage for the ERV. In this research, an advanced intra-link emergency assistance system, that leverages the emerging technologies of the connected vehicle environment, is proposed. The proposed system assumes the presence of a centralized system that gathers/disseminates information from/to connected vehicles via vehicle-to-infrastructure (V2I) communications. The major contribution of this dissertation is the intra-link level support provided to ERV as well as non-ERVs. The proposed system provides network-wide assistance as it also considers the routing of ERVs. The core of the system is a mathematical program - a set of equations and inequalities - that generates, based on location and speed data from connected vehicles that are downstream of the ERV, the fastest intra-link ERV movement. It specifies for each connected non-ERV a final assigned position that the vehicle can reach comfortably along the link. The system accommodates partial market penetration levels and is applicable on large transportation link segments with signalized intersections. The system consists of three modules (1) an ERV route generation module, (2) a criticality analysis module and (2) the sequential optimization module. The first module determines the ERV's route (set of links) from the ERV's origin to the desired destination in the network. Based on this selected route, the criticality analysis module scans/filters the connected vehicles of interest and determines whether any of them should be provided with a warning/instruction message. As the ERV is moving towards its destination, new non-ERVs should be notified. When a group of non-ERVs is identified by the criticality analysis module, a sequential optimization module is activated. The proposed system is evaluated using simulation under different combinations of market penetration and congestion levels. Benefits in terms of ERV travel time with an average reduction of 9.09% and in terms of vehicular interactions with an average reduction of 35.46% and 81.38% for ERV/non-ERV and non-ERV/non-ERV interactions respectively are observed at 100% market penetration, when compared to the current practice where vehicles moving to the nearest edge.
Doctor of Philosophy
Downstream vehicles detect an emergency response vehicle (ERV) through sirens and/or strobe lights. These traditional warning systems do not give any recommendations about how to react, leaving the drivers confused and often adopting unsafe behavior while trying to open a passage for the ERV. In this research, an advanced intra-link emergency assistance system, that leverages the emerging technologies of the connected vehicle environment, is proposed. The proposed system assumes the presence of a centralized system that gathers/disseminates information from/to connected vehicles via vehicle-to-infrastructure (V2I) communications. The major contribution of this dissertation is the intra-link level support provided to ERV as well as non-ERVs. The proposed system provides network-wide assistance as it also considers the routing of ERVs. The core of the system is a mathematical program - a set of equations and inequalities - that generates, based on location and speed data from connected vehicles that are downstream of the ERV, the fastest intra-link ERV movement. It specifies for each connected non-ERV a final assigned position that the vehicle can reach comfortably along the link. The system accommodates partial market penetration levels and is applicable on large transportation link segments with signalized intersections. The system consists of three modules (1) an ERV route generation module, (2) a criticality analysis module and (2) the sequential optimization module. The first module determines the ERV’s route (set of links) from the ERV’s origin to the desired destination in the network. Based on this selected route, the criticality analysis module scans/filters the connected vehicles of interest and determines whether any of them should be provided with a warning/instruction message. As the ERV is moving towards its destination, new non-ERVs should be notified. When a group of non-ERVs is identified by the criticality analysis module, a sequential optimization module is activated. The proposed system is evaluated using simulation under different combinations of market penetration and congestion levels. Benefits in terms of ERV travel time with an average reduction of 9.09% and in terms of vehicular interactions with an average reduction of 35.46% and 81.38% for ERV/non-ERV and non-ERV/non-ERV interactions respectively are observed at 100% market penetration, when compared to the current practice where vehicles moving to the nearest edge.

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16

Andersson, Agneta Helen. "Everything Is Connected to Everything Else : An Ecocritical and Psychological Approach to Jane Urquhart's The Stone Carvers". Thesis, Högskolan i Halmstad, Sektionen för humaniora (HUM), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-23394.

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Nature is everywhere. Every day we have contact with it. Still, many of us do not realize how important it is for our survival. Descriptions of nature have always been present in novels. However, recently the aspect of nature in literature, as well as in other disciplines, has been dealt with in a slightly different way. As a result, an ecocritical approach to literature has been favoured. This essay shows nature's impact on the characters in Jane Urquhart's The Stone Carvers. Using this novel as an example, I start by studying how the concept of nature is often constructed through opposition. I then move on to show how stereotypical boundaries between nature and human beings may be challenged. Finally I study how nature function as a healing agent in The Stone Carvers. In my studies I combine the theories of ecocriticism with a psychoanalytical perspective through the concept of abjection.

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17

Belmekki, Sabrine. "Multi-level risk and collective perception for high quality of service automated mobility in a highly dynamic V2X connected environment". Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILB009.

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Les technologies des véhicules automatisés se développent rapidement et sont deplus en plus présentes dans notre vie quotidienne pour créer des systèmes de trans-port entièrement connectés. Les constructeurs automobiles équipent à présent lesderniers modèles de véhicules de certaines fonctions d'aide à la conduite. Les avan-tages potentiels de ces véhicules incluent la réduction des collisions, l'atténuationdes embouteillages, la réduction de la consommation de carburant, et une flexibil-ité accrue pour les personnes qui n'ont pas accès aux transports. Pour permettrel'automatisation de ces fonctions, il est nécessaire de disposer de données relativesà la détection d'obstacles, la configuration de la route et l'environnement.L'objectif de cette étude est d'examiner l'adaptabilité et l'aptitude du modèle decommunication de la feuille de branche de chaîne (Chain Branch Leaf-CBL) dansles systèmes coopératifs et d'examiner son impact sur les réponses de la circula-tion. De plus, la recherche vise à déterminer le rôle des unités en bord de route etl'efficacité de la perception à plusieurs niveaux dans la prévention des risques. Lebut ultime de cette recherche est d'améliorer la communication et la collaborationentre les véhicules conventionnels et autonomes, ce qui se traduira par une circu-lation plus sûre et plus efficace.Dans cette thèse, nous avons étudié l'utilisation d'une architecture et des stratégiesde communication adaptées pour améliorer la qualité de service en utilisant les in-formations des véhicules entourant l'égo véhicule. Nous avons proposé le conceptde Chain Branch Leaf-Gateway Clustering pour réaliser une topologie optimaled'unité de bord de route-UBR assurant une haute qualité et continuité de service.Nous avons également étudié la perception multi-niveau pour estimer les risquesde collision multi-niveau (local, local étendu, branche étendu et global).Par la suite, nous utilisons les métriques (Time to collision (TTC), Time TimeHeadway (TH), Distance of Gruyer (DG), Risk estimator with uncertainties andmultidimensional model (RIMUM)). Pour estimer les quatre risques de collision(étendus) dans des conditions optimales avec une localisation et une perceptionparfaites, et la situation d'incertitude de la perception avec une localisation par-faite. Les résultats montrent que les risques étendus permettent une meilleureanticipation de la collision que le risque local.De plus, nous avons développé une nouvelle version étendue du modèle Chainbranch leaf-Gateway (CBL-G), qui s'avère plus efficace en termes de couverture.L'architecture hiérarchique du modèle nous permet de calculer les risques de col-lision avec une plus grande précision. La classification en différents niveaux derisque nous permet de identifier les situations potentiellement dangereuses. Dans nos projets de recherche futurs, nous planifions d'étudier d'autres situationstelles que les intersections routières, les sorties et les entrées d'autoroutes ainsique les ronds-points. De plus, nous aimerions explorer les cas dans lesquels il est impossible de localiser les nœuds à travers la chaîne en passant à travers des tun-nels et élaborer des indicateurs de risque qui explorent tous les composants clés(véhicule ego, conducteur, obstacle, route et environnement)
The use of automated vehicle (AV) technologies such as self-driving cars is becoming more prevalent in daily life. These technologies aim to create fully- connectedtransportation systems, still there are concerns that remain unaddressed. Studieshave shown that AVs can reduce collisions, ease traffic congestion, and providetransportation options for those who lack access. Yet, car manufacturers havealready implemented certain automated features in their vehicles. One importantaspect of AVs is improving communication between the vehicle and roadside.The objective of this study is to investigate the adaptability and suitability of theChain branch leaf (CBL) communication model in cooperative systems to exam-ine its impact on traffic responses. Additionally, the research aims to determinethe role of Roadside Units and the effectiveness of multi-level perception in riskmitigation. The ultimate goal of this research is to improve communication andcollaboration between autonomous vehicles leading to safer and more efficient traf-fic flow.This thesis focuses on the estimation of obstacle attributes, the road, and theego-vehicle to improve the quality of service on the road through communication,localization, and perception functions. We propose architectures and communica-tion strategies that will take into account the information of surrounding vehiclesto optimize coverage and estimate collision risk at different levels including local,extended local, extended branch, and global.Subsequently, we use the most relevant metrics (Time to Collision (TTC), TimeHeadway (TH), Distance of Gruyer (DG), RISK (R), Risk estimator with Uncer-tainties and Multidimensional model (RIMUM)), to estimate the four (extended)collision risks. In optimal conditions first with perfect location and perception,and then the uncertainty scenario of perception with perfect location. Resultsshow that the extended risks allow better anticipation of the collision than thelocal risk.Furthermore, we have developed a new extended version of the Chain branch leaf-Gateway (CBL-G) model, which proves to be more efficient in terms of coverage.The hierarchical architecture of the model allows us to calculate collision riskswith greater accuracy. The different levels of risk allow us to identify potentiallydangerous situations earlier, which is considered to be very relevant for incidentprevention.In our future research projects, we plan to study other situations such as roadintersections, highway exits, and entrances, as well as roundabouts. Additionally,we would also like to explore cases where we are unable to locate nodes throughthe chain (such as passing through tunnels). And elaborate risk indicators thatexplore all key components (ego vehicle, driver, obstacle, road, and environment)

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18

Thulin, Pauline y Mattias Henricson. "THE CONNECTED ELEPHANT IN THE ROOM: A study on adoption factors for the Internet of Things in the smart home environment". Thesis, Malmö universitet, Fakulteten för teknik och samhälle (TS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20361.

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Majoriteten av svenskarna (86%) tror att vi kommer se allt fler uppkopplade produkter i våra hem, men det är bara 33% som faktiskt vill ha fler smarta produkter i sina hem. I denna studie har författarna undersökt vilka faktorer som är centrala i svenska konsumenters adoption av IoT-produkten Facebook Portal, för att bidra med ökad förståelse för konsumenters motstånd mot användandet av denna typ av produkter. Utifrån en värdebaserad acceptansmodell (VAM) genomfördes en kvantitativ enkätundersökning där potentiella konsumenters attityd till användandet av Facebook Portal undersöktes utifrån faktorerna upplevd användbarhet (PU), upplevt nöje (PE), upplevd integritetsrisk (PPR) och upplevd påflugenhet (PI), i relation till det uppfattade värdet (PV) av produkten. Studien visade att upplevd användbarhet (PU) och upplevt nöje (PE) har ett starkt positivt samband med potentiella användares upplevda värde (PV) av Facebook Portal samt att upplevd dataintegritetsrisk (PPR) och upplevd påflugenhet (PI) har medelstarka negativa samband med potentiella konsumenters upplevda värde (PV) av produkten. Studien visade också att respondenter som identifierar produkten som användbar (PU) och upplever produkten som rolig (PE) också tenderar att vara mindre medhållande i att produkten utgör ett hot mot integriteten (PPR) eller upplevs påträngande (PI).
The majority of Swedes (86%) believe that smart home devices is a rising trend, yet only 33% actually want more smart objects in their homes. In this study, the authors elucidate the factors central to the Swedish consumers’ adoption of the IoT product Facebook Portal, to contribute to the understanding of their resistance to the use of this type of technology. Through a value based acceptance model (VAM), the authors conducted a quantitative survey, investigating consumers' attitudes toward the use of Facebook Portal through the factors perceived usefulness (PU), perceived enjoyment (PE), perceived privacy risk (PPR) and perceived intrusiveness (PI), in relation to the perceived value (PV) of the product. Perceived usefulness (PU) and perceived enjoyment (PE) showed a strong positive correlation to potential users' perceived value (PV) of Facebook Portal and perceived privacy risk (PPR) and perceived intrusiveness (PI) showed a medium strong negative correlation to potential consumers' perceived value (PV) of the product. The study also showed that respondents who identify the product as useful (PU) and perceive the product as enjoyable (PE) also tend to be less supportive in the claims that the product comes with a privacy risk (PPR) and/or is perceived as intrusive.

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19

By, Shenhjie Zheng y Xucheng Liu. "The pursuit of peaceful development : How China's foreign policy and its national security are connected". Thesis, Högskolan i Halmstad, Akademin för hälsa och välfärd, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-29305.

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Since the Open-Door Policy has been carried out in 1979, China has gained dramatic improvements in many fields, such as economies and military. At the same time, the considerable changes also bring China many crises from the complicated international envirorunent. This thesis will illustrate these questions through nationalism and realism theoretical framework by using case study with a qualitative approach as the method. With the Five Peaceful Principles of Co-existence based foreign policy, this thesis will experience "Century of Humiliation" of China again and redefine the rising power of China through a case study about Diaoyu/Senkaku Islands dispute between China and Japan. Although it is a little hard to analyze this case under a complicated international environment, plenty of document information will support to get a result of how China's foreign policy and national security are interlinked? Finally, "national insecurities" and "humiliating history" are drawn as the key factors that affect China's foreign policy making, and the interconnections of China's peaceful diplomacy and national security. "National insecurities" and "humiliating history" drive China to make the foreign policy of peaceful development, otherwise, to ensure national security, China need to strengthen the comprehensive national power.

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20

Haidar, Haidar. "An empirical analysis of controlled risk and investment performance using risk measures : a study of risk controlled environment". Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/48106/.

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In this thesis, I study the performance behaviour of hedge funds and mutual funds. I study a basket of various risk statistics that are widely used to measure the fluctuation of asset prices. Those risk statistics are used to rank the performance of the assets. The linear dependence relation of these risk measures in ranking assets is investigated and the set of risk measures is reduced by excluding risk measures that produce linearly dependent ranking vectors to other risk measures. The ranks within each of the selected remaining risk statistics are standardised and then linearly transformed into a new set of linearly independent factors where principal component analysis is carried out as a variable reduction technique to remove the noise while preserve the main variation of the original data. The transformed factors are sorted in descending order according to their contribution to the variation of the original data. The factor loadings of the first two principal components PC1 and PC2 are reviewed and interpreted as styles (PC1 as consistency and PC2 as aggression). The universe of a set of hedge funds is classified according to these styles as BL=(low consistency, low aggression), BR=(high consistency, low aggression), TL=(low consistency, high aggression) and TR=(high consistency, high aggression). I examine the performance behaviour of the four different classified classes whereby this classification method provides an indication on returns and management styles of hedge funds. A three-factor prediction model for asset returns is introduced by regressing 12 weeks' forward rank of return on the historical ranks of risk statistics. The first few principal components, which explain the main variation of information captured by risk statistics, are used in the prediction model. The robustness of the model is tested by applying the model to the following 12-week period using the set of independent factors. An investment strategy is constructed based on the prediction model using the set of independent factors. I discover high evidence of predictability and I test for out-of-sample forecasting performance. I then examine the use of subsets of risk statistics from the basket rather than using the set of all risk statistics. I further study the use of the so-called σ2/μ risk measure in predicting the market “turning point” of performance of a portfolio of hedge funds. Risk measure quantity σ2/μ replaces the traditional variance σ2 in the Black-Scholes option valuation formula when it is evaluated for hedge funds.

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21

Tan, Qun. "Environment, marketing strategy, performance, and international exit : why and how they are connected : a study on international exit in the Chinese Outward Foreign Direct Investment (OFDI) context". Thesis, Durham University, 2013. http://etheses.dur.ac.uk/7754/.

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Although research on foreign market entry and expansion behaviour has attracted significant interest in the literature, there is a general lack of research (both conceptual and empirical) on the exit behaviour of Foreign Direct Investment (FDI) firms. To address this issue, the current study develops a conceptual framework by extending the Environment-Strategy-Performance (ESP) paradigm to include the exit decision as a consequence of current performance. This thesis draws notions from various theories including the ESP paradigm, fit theory, dynamic capabilities (DC) theory, and the theory of competitive advantage. The objective is to take an initial step towards reducing the discrepancy between previous conceptual research and empirical research on exit, by developing a conceptual framework and empirically examining it in the context of Chinese Outward Foreign Direct Investment (OFDI). It also aims to lay the conceptual foundation for subsequent empirical research on international marketing and international exit. Several research hypotheses are advanced and tested using questionnaire survey data. The main research results show that both dissatisfactory performance of a foreign affiliate, and the internal strategic misfit between a foreign affiliate and its headquarters are important triggers of the exit decision. However, when the moderating role of a foreign affiliate’s marketing capabilities is considered, the impact of strategic misfit on the exit decision becomes not significant, whereas the influence of dissatisfactory performance on the exit decision remains significant. The research results have generated new insights into both international marketing strategy and international exit behaviour. Implications for both headquarters’ managers and foreign affiliates’ managers are also discussed.

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22

Goel, Shlok. "Research, Design, and Implementation of Virtual and Experimental Environment for CAV System Design, Calibration, Validation and Verification". The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595368946630713.

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23

Richa, Jean Raphaël. "Amélioration de l'ingénierie des données dans les environnements connectés grâce à la détection de la propagation et de l'obsolescence des données". Electronic Thesis or Diss., Pau, 2024. http://www.theses.fr/2024PAUU3077.

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La croissance incessante des technologies numériques a renforcé les capacité à détecter, visualiser, analyser et gérer de manière autonome l'environnement qui nous entoure. Intelligent et plus connecté est la tendance dominante au sein du métavers émergent, où des environnements connectés sont conçus pour recueillir d'énormes quantités de données. Ces environnements contribuent à une meilleure compréhension des activités humaines, améliorent la qualité de vie et favorisent la durabilité. Cette thèse introduit deux concepts clés - le continuum de zones et l'obsolescence des données - visant à approfondir la sensibilisation aux environnements connectés en expliquant comment les données se déplacent entre les zones et en détectant quand les données deviennent pertinentes dans leur contexte. En abordant ces aspects souvent négligés, nous visons à améliorer l'interprétation et la gestion des données dans les environnements connectés.Cette thèse aborde quatre défis clés : (1) concevoir un modèle de données hautement expressif qui capture efficacement les composants essentiels des environnements connectés, y compris les zones d'accueil, les dispositifs intelligents et leurs réseaux de capteurs associés ; (2) établir un mécanisme pour identifier et tracer comment les données se propagent entre différentes zones ; (3) proposer une approche à grande échelle pour détecter l'obsolescence des données tout en tenant compte de l'ensemble de l'environnement ; et (4) traiter la nature dynamique des environnements connectés, telle que la mobilité des dispositifs, les pannes et les changements dans les configurations de zone (par exemple, fusionner plusieurs zones ou diviser une zone en plusieurs).Pour relever ces défis, nous proposons d'abord le modèle de données HSSN+ pour représenter de manière résiliente les éléments principaux dans les environnements connectés.Ensuite, en nous appuyant sur ce modèle, nous présentons deux cadres étroitement liés. Le premier est le cadre de calcul de continuité de zones pour les environnements connectés, qui formalise la notion de continuité de zones et permet de comprendre comment les données circulent entre les zones. Le second est le cadre de détection de l'obsolescence des données dans les environnements connectés, qui fournit une méthode structurée d'identification et de calcul de l'obsolescence des données sur la base de mesures de qualité prédéfinies.Les deux cadres permettent un contrôle et une compréhension efficaces de tous les environnements connectés
The relentless expansion of digital technologies has enhanced the capabilities of collecting, visualizing, analyzing, and autonomously managing the environment surrounding us.Intelligent and increasingly connected is the prevailing trend within the rising metaverse, where connected environments are driven to gather a plethora of data.These environments contribute to a better understanding of human activities, improve quality of life, and ease paths for sustainability.This thesis introduces two pivotal concepts - zone continuum and data obsolescence - furthering awareness of connected environments by explaining how data crosses between zones and detecting when data becomes irrelevant with respect to its environment.By addressing these overlooked aspects, we aim to improve data interpretation and management within connected environments.This thesis addresses four key challenges: (1) designing a deep and expressive data model that effectively captures the core components of connected environments, such as hosting zones, smart devices, and their corresponding sensor networks; (2) establishing a mechanism to discover and trace how data propagates between different zones; (3) proposing a large-scale approach to detect data obsolescence while considering the entire environment; and (4) handling the dynamic nature of the CE that could be illustrated by the mobility and failure of the devices, as well as modifications in zone configurations (e.g., combining multiple zones into one or dividing a single zone into several).To address these challenges, we first propose the HSSN+ data model, which underpins a resilient representation of the elements in connected environments.Consequently, in light of this model, we put forward two interconnected frameworks. The first one is the Zone Continuum Computation for Connected Environments (ZCCCE) framework that formalizes the zone continuum concept and enables to understand how data moves between zones. The second one is the Data Obsolescence Detection in Connected Environments (DODCE) framework which offers a structured approach to identify and compute the data obsolescence based on predefined quality indicators.These two frameworks provide opportunities for effective control and understanding in connected environments

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24

Campbell, Benjamin. "Large-scale grid-connected renewable energy in Australia: Potential barriers, strategies and policy support mechanisms that may affect RE development from the perspective of energy specialists at a leading consultancy operating in the built environment in Australia". Master's thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/32564.

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Barriers to renewable energy development in the past have been identified as high upfront costs with challenges around equity and debt financing, as well as limited legal frameworks and limited regulatory support. Although it is noted that barriers to development are country specific, as well as the solutions to overcome such barriers. Policy measures implemented in various countries to support renewable energy have been seen to have a marked impact on its development. The renewable energy industry in Australia is showing unprecedented growth with a drastic change in the energy landscape expected in the future, should all proposed developments come to fruition. Renewable energy in Australia is currently in its infancy though. It is expected that the planned integration of all the proposed developments in the National Electricity Market will result in certain barriers to development emerging at higher levels of integration. Australia's energy policy has taken significant steps to supporting the deployment of cleaner generation technologies, although hurdles at federal and state level have in the past frustrated the development of renewable energy. The history and status quo of renewable energy development in Australia has been investigated. The current framework and support structures in place as well as potential barriers have been reviewed. A qualitative investigation utilising a single case study approach was selected as the research method. The case investigated was the renewable energy division of a leading global engineering consultancy operating in Australia. The participants of the study included the senior management staff in the renewable energy division of the company. Standard open-ended interviews were conducted. The data was analysed by employing a method of pattern matching. The observed data from the interview process was analysed and compared against the expected pattern which had emerged from the literature. Potential barriers and support strategies have been outlined as a conclusion to the study. The study found federal energy policy to be favourable, but not vital for continued growth of RE development. It was acknowledged that a focus on grid infrastructure would be vital to avoid constricting asset development. The development of Renewable Energy Zones was considered a favourable strategy to overcoming barriers identified, although it was noted that community acceptance would be a significant consideration. Gas generation may form part of the future energy mix, but will be dependent on price and emergent technology. Pumped hydro power is expected to be an important compliment to renewable energy in future, to assist in addressing the technical barriers associated with high levels of non-synchronous generation in the network. A reform of the NEM may also be required to cater for a scenario of a significant penetration of renewable energy and is a topic recommended for future research.

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25

Yan, Steven Longfei [Verfasser] y A. [Akademischer Betreuer] Albers. "Vernetzte Validierungsumgebungen – ein Beitrag zur Validierung im verteilten Produktentwicklungsumfeld auf Basis des IPEK-X-in-the-Loop-Ansatzes am Beispiel der Antriebssystementwicklung = Connected Validation Environments – A Contribution to Validation in a Distributed Product Development Environment Based on the IPEK-X-in-the-Loop-Approach Using the Example of Powertrain System Development / Steven Longfei Yan ; Betreuer: A. Albers". Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1235072428/34.

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Guo, Yi. "Connected and Automated Traffic Control at Signalized Intersections under Mixed-autonomy Environments". University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1613752599541812.

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Teehan, Paul. "Integrative approaches to environmental life cycle assessment of consumer electronics and connected media". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/47025.

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The environmental impacts of information and communication technologies and consumer electronics are challenging to evaluate. Organizations and individuals wishing to reduce the impacts attributable to their usage of these products and systems rely on a limited technical knowledge base that struggles to stay current. Using a life cycle assessment approach which expresses environmental impacts quantitatively in terms of greenhouse gas emissions and primary energy demand, this dissertation significantly expands our understanding of the impacts of desktop computers, electronics products in general, and connected media services accessed in the home, in order to support environmentally-conscious decision-making and policy regarding these products and systems. The first of three studies, a meta-analysis of prior life cycle assessments of desktop PCs, resolves an important ambiguity in this literature and demonstrates that greenhouse gas emissions due to operational energy consumption usually exceed those due to device manufacturing. The second study calculates embodied greenhouse gas emissions of eleven electronics products through a teardown analysis, and finds a linear relationship between mass and embodied emissions, thus demonstrating that lightweight, compact products offer environmental benefits relative to larger products. A comparison to studies of older products also reveals that newer products are more materially efficient, largely due to reduction in integrated circuit content per product. Finally, the third study calculates aggregate US consumer greenhouse gas emissions due to broadcast television, video on demand, online video, other online uses, and offline uses when consumed using televisions, personal computers, tablets, and smartphones, including emissions due to devices in the home, networks, and datacenters. The study concludes that emissions due to video end-uses account for 75% of total consumer ICT emissions. About 71% of consumer ICT emissions arise due to devices in the home, especially TVs and desktop PCs, with the remainder due to networks and datacenters. Mobile platforms using Wi-Fi connections are the least impactful mode of consuming connected media content. Collectively, the dissertation argues for a more integrated approach towards impact estimation, in order to surmount issues regarding variation of modeling assumptions across existing studies, longevity of published work, and coverage of emerging products and services.

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28

Keshariya, Mayank. "Extended Policy-Based Management Framework to Provide Always Best Connected Services in Heterogeneous Mobile Environments". Thesis, University of Canterbury. Computer Science and Software Engineering, 2009. http://hdl.handle.net/10092/2549.

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The growth in the popularity of Internet services, increasing demands of mobile users together with a wide range of access technologies and mobile-networked devices, introduces the notion of integration and inter-working of heterogeneous access networks. Sometimes referred to as 4th generation (4G) networks, the overall objective of this research is to provide a managed Always Best Connected (ABC) service over underlying heterogeneous wireless and mobile platforms while maintaining negotiated security and Quality of Service in a scalable and modular environment. This research proposes a new model and its architecture for policy-based management (PBM) to provide a framework for the centralised management of networks based on business-level policies. This work extends existing IETF Policy-based Network Management (PBNM) model by introducing a new layered-approach which facilitates the negotiation of management services over interconnected heterogeneous mobile platforms, thus achieving an ABC scenario. The proposed layered-approach provides flexibility to the organisations so that they can choose favourable semantic and syntactic approaches and facilitates the separation of management policies from their implementation in a distributed and heterogeneous environment. The extended Policy Information Model and a new policy conflict detection technique are also introduced. Further, we have proposed and implemented a new model of a policy-managed mobile client and its architecture to support seamless handoff across multiple access networks. The proposed mobile client supports multi-domain authentication and security along with downloadable user profiles. We have also proposed and implemented a network selection algorithm and introduced a new Infrastructure parameter, which assists in selecting an optimum time and the best available access network to handoff. We present performance analysis to validate our architectural approach.

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29

Anany, Hossam. "Effectiveness of a Speed Advisory Traffic Signal System for Conventional and Automated vehicles in a Smart City". Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156650.

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This thesis project investigates the state-of-the-art in traffic management "Green Light Optimal Speed Advisory (GLOSA)" for vehicles in a smart city. GLOSA utilizes infrastructure and vehicles communication through using current signal plan settings and updated vehicular information in order to influence the intersection approach speeds. The project involves traffic microscopic simulations for a mixed traffic environment of conventional and automated vehicles (AVs) both connected to the intersection control and guided by a speed advisory traffic management system. Among the project goals is to assess the effects on traffic performance when human drivers comply to the speed advice. The GLOSA management approach is accessed for its potential to improve traffic efficiency in a full market penetration of connected AVs with absolute compliance. The project also aims to determine the possible outcome resulting from enhancing the AVs capabilities such as implementing short time headways between vehicles in the future. The best traffic performance results achieved by operating GLOSA goes for connected AVs with the lowest simulated time headway (0.3 sec). The waiting time reduction reaches 95% and trip delay lessens to 88 %.

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30

Zinn, Brendan Anderson 1977. "Mass transfer and dispersion processes in connected conductivity structures : simulation, visualization, delineation and application". Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29584.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2003.
Includes bibliographical references (p. 161-167).
This thesis focuses on mass transfer behavior, i.e., tailing, in solute transport, and on hydraulic conductivity heterogeneity. Macrodispersive theory, generally used to incorporate heterogeneity into solute transport, does not account for this tailing and makes assumptions about the structural characteristics of the heterogeneity, specifically that the field is multivariate gaussian. We move away from the multigaussian assumption to focus on the concept of connected pathways of high or low conductivity. We first motivate the importance of connected extreme conductivity values through the numerical creation of two-dimensional conductivity fields with nearly identical univariate conductivity distributions and covariances, but with varying connectedness of extreme values. We simulated flow and transport through these fields, using a particle tracking approach that incorporates advection and diffusion. We demonstrate that connectedness impacts flow by influencing the effective conductivity of the field, and connected high conductivity fields with relatively high variance displayed mass transfer behavior, driven by both advective and diffusive processes. We then conducted laboratory experiments to study three flow situations demonstrated by the first part of the work - classic dispersion, diffusion-driven mass transfer, and advection-driven mass transfer. By simultaneously measuring outflow concentration and the spatial distribution of solute in the tank, we demonstrate different breakthrough characteristics driven by different small-scale processes. Outflow concentrations match excellently with established models in the case of diffusive mass transfer and dispersion, and relatively well with a model we developed for the advective mass transfer scenario.
(cont.) We generalized the experimental results by creating connected binary conductivity fields, delineating the conditions of connectedness and conductivity contrast that drive the various transport. Finally, we examine the implications of our earlier work, particularly the interplay between advection and diffusion in mass transfer. The presence of both processes creates late-time concentrations that are complex, but partially dependant on hydraulic gradients. We apply this to a hypothetical scenario of a pump-and-treat remediation - the existence of advective mass transfer creates situations in which solute mobilization can be sped up by pumping rate choices, and the complex interaction between mass transfer processes leads to more complex pumping rate decisions.
by Brendan Anderson Zinn.
Ph.D.

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31

Mansour, Elio. "Détection d’évènements dans des environnements connectés". Thesis, Pau, 2019. http://www.theses.fr/2019PAUU3017/document.

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L’intérêt croissant pour les environnements connectés (bâtiments, villes, usines intelligents) etl’évolution des réseaux de capteurs, technologies de gestion/communication de données ont ouvertla voie à des applications intéressantes et utiles qui aident les utilisateurs dans leurs tâchesquotidiennes (augmenter la productivité dans une usine, réduire la consommation d’énergie).Cependant, diverses améliorations sont encore nécessaires. Par exemple, comment améliorer lareprésentation de ces environnements complexes, dynamiques et hétérogènes. En outre, commentfaciliter l’interaction entre les utilisateurs et leurs environnements connectés et comment fournir desoutils de surveillance et de gestion de tels environnements.Dans cette thèse, nous nous concentrons sur quatre défis principaux: (i) représenter un ensemblediversifié de composants et d’éléments liés à l’environnement et à son réseau de capteurs; (ii) fournirun langage de requête qui gère les interactions utilisateur/environnement connecté (pour la définitionde l’environnement, la gestion de données, la définition d’événements); (iii) faire face à la dynamiquede l’environnement et à son évolution dans le temps; et (iv) proposer un mécanisme générique dedétection d’événements pour mieux surveiller l’environnement.Pour ce faire, nous présentons d’abord un modèle de données basé sur une ontologie qui représentedes environnements et réseaux de capteurs hybrides. Couvrant ainsi divers capteurs (statique, mobile),environnements (infrastructures, équipements) et données (scalaires, multimédia). Ensuite, nousintroduisons un langage de requête que l’on pourrait utiliser pour diverses tâches (définirl’environnement connecté, la recherche d’informations, la définition d’événements, la gestion dedonnées). De plus, afin de suivre les changements d’environnement, nous fournissons un optimiseurde requêtes qui permet aux requêtes soumises de gérer la dynamique de l’environnement avant leurexécution. Enfin, nous proposons un noyau de détection d’événement qui prend en entrée lesdéfinitions d’événement et détecte les événements ciblés.Nous regroupons les modules susmentionnés dans un framework global pour la détectiond’événements dans des environnements connectés. Notre proposition est générique, extensible, etpourrait être utilisée avec différents environnements connectés tels que des bâtiments, des villes. .
The rising interest in smart connected environments (e.g., smart buildings, cities, factories) and theevolution of sensors, data management/communication technologies have paved the way forinteresting and useful applications that help users in their every day tasks (e.g. increasing comfort,reducing energy consumption). However, various improvements are still required. For instance, howto enhance the representation of such complex, dynamic, and heterogeneous environments.Moreover, how to facilitate the interaction between users and their connected environments, and howto provide tools for environment monitoring and management.In this thesis, we focus on four main challenges: (i) representing a diverse set of components andelements related to the environment and its sensor network; (ii) providing a query language thathandles user/connected environment interactions (e.g., environment definition, data management,event definition); (iii) coping with the dynamicity of the environment and its evolution over time; and(iv) proposing a generic event detection mechanism for improved environment monitoring.To do so, we first present an ontology-based data model that represents hybrid environments/sensornetworks. Thus covering diverse sensors (e.g., static, mobile), environments (e.g., infrastructures,devices), and data (e.g., scalar, multimedia). Then, we introduce a query language that one might usefor various tasks (e.g., defining the connected environment, information retrieval, event definition,data management). Furthermore, to keep up with the environment changes we provide a queryoptimizer that allows the submitted queries to cope with the dynamicity of the environment prior totheir execution. Finally, we propose an event detection core that takes event definitions as input anddetects the targeted events.We group the aforementioned modules in one global framework for event detection in connectedenvironments. Our proposal is generic, extensible, and could be used with different connectedenvironments such as buildings, cities. .

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32

McCall, Amy Jean Taylor. "Structural Analysis and Optimization of Skyscrapers Connected with Skybridges and Atria". BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3829.

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Skybridges and atria between buildings are becoming more and more popular. Most current skybridge connections are either roller or rigid-connections. This dissertation presents an investigation of the structural analysis and optimization of skyscraper systems with hinge-connected skybridges, and compares the results to skyscraper systems with roller-connected skybridges and to skyscraper systems without skybridges altogether. Also presented is an investigation of the structural analysis and optimization of skyscrapers both with and without atria between the buildings. It was assumed that the atria envelope was constructed with cushions made from lightweight, transparent, and flexible Ethylene Tetrafluoroethylene (ETFE). A simplified skyscraper skybridge model (SSSM) was developed to approximate analysis of such systems. The SSSM identifies and includes only the dominant degrees of freedom (DOF's) when assembling the structure stiffness matrix. This greatly reduces computational time and computer memory compared to traditional finite element models (FEM). The SSSM is fast enough to be used with both gradient-based and genetic optimization algorithms. The steps of the SSSM consist of: 1) determination of megacolumn areas, 2) constructing the stiffness matrix, 3) evaluation of volume, weight, mass and period, 4) calculation of lateral force vectors, and 5) calculation of displacement and stress constraints. Three skyscraper systems were analyzed using both the SSSM and a FEM to compare both the accuracy and efficiency of the SSSM. It was found that the SSSM was very accurate for displacements (translations and rotations), and core, megacolumn, outrigger, and skybridge stress. It was also found that the SSSM analysis time was significantly faster and used far less computer memory than FEM. Four skyscraper systems were optimized for two different sites, with varying atria and skybridge conditions, using gradient-based and genetic optimization algorithms. The optimization strategy consisted of a series of executions of the sequential quadratic programming (SQP) algorithm, followed by executions of the generalized reduced gradient (GRG) algorithm, followed by executions of a discrete genetic algorithm. The genetic algorithm made significant progress for two of the systems. Optimal results showed that in some cases hinge skybridges and atria envelope produced significantly lighter systems compared to roller, no skybridge, or without atria envelope cases.

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33

Evangelakos, Lee Eleni. "Investigating and prototyping a connected device strategy and solution for industrial equipment manufacturers". Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/117980.

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Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, in conjunction with the Leaders for Global Operations Program at MIT, 2018.
Thesis: S.M., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, in conjunction with the Leaders for Global Operations Program at MIT, 2018.
"June 2018." Cataloged from PDF version of thesis.
Includes bibliographical references (pages 69-70).
Shape Technologies makes industrial waterjet equipment that is purchased and used by customers to process a variety of materials (ranging from metal to food). To date the company has not invested in connecting their machines and as a result no engineering, sales or service processes benefit from machine usage or health data. Similarly, the customer service experience is not optimized. Most customers follow a break-fix pattern and engage non-SHAPE technicians for service and replacement parts after their initial equipment purchase. The motivation for this project is to harness recent innovations in and availability of sensor and data storage technology to serve the business of an industrial manufacturing company. This project leverages established Industrial Internet of Things (IIoT) use-cases to develop an IloT product and business plan for SHAPE Technologies that would also allow for future iteration and growth in this space. The contribution of this thesis is in three parts. First, it demonstrates many concepts described in the loT literature including transitioning to a servitization business model, deciding which parts of loT to make vs. buy and designing a usable application for industrial users. Second, it demonstrates the value of an inclusive product development process in bringing an organization through a discontinuous technology transition. And third, it provides early insight into the types of data and modeling methods that will enable powerful predictive modeling for SHAPE and its customers. The final result of this project was to develop a prototype IloT application that runs on one in-house SHAPE machine. It was developed in conjunction with a broad team of stakeholders from across the SHAPE organization and is currently collecting an initial data sample and serving as a catalyst for ongoing IloT conversations at SHAPE.
by Lee Eleni Evangelakos.
M.B.A.
S.M.

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34

Mendes, David José Murteira. "GNU prolog to Java: a study on how to connect the two programming environments". Master's thesis, Universidade de Évora, 2004. http://hdl.handle.net/10174/15085.

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Neste trabalho pretende-se efectuar o estudo e a implementação de uma interface bidireccional entre o GNU-Prolog e a linguagem Java. O objectivo desta ferramenta é dar a possibilidade de utilizar o poder da programação em lógica dentro de um ambiente multi-plataforma. Pretende-se possibilitar a escrita de programas Prolog que invocam métodos Java e programas Java que chamam predicados Prolog. Java e Prolog são um par ideal para disponibilizar úteis "aplicações inteligentes", com interfaces actuais, disponibilizadas para diferentes sistemas operativos existentes. Misturada com o Java esta "inteligência" beneficia das características desta linguagem como independência de plataformas, segurança, tratamento de excepções e segurança de tipos entre outras. Uma ligação destas possibilita a criação de ferramentas tais como servidores para diagnóstico de problemas, aplicações robot que se deslocam automatizadamente na Internet, agentes inteligentes móveis que atendem pedidos de outros agentes com capacidade de raciocínio sejam humanos ou não. Um dos objectivos primários, no entanto, que se pretende atingir é a integração de uma implementação Prolog compatível ISO e open source com todos os ambientes de desenvolvimento e ferramentas Java disponíveis actualmente. Como tal a ligação pretendida é feita a nível muito baixo para poder apresentar características de alta performance, flexibilidade e portabilidade. /*** Abstract - This work is intended to study and put up a bidirectional interface between GNU-Prolog and the Java language. The purpose of this tool is the possibility to use the power of logic programming within a cross platform environment. This meaning to write prolog programs invoking java methods and Java programs calling prolog predicates. Java and Prolog are an ideal pair for delivering useful intelligent applications with state-of-the-art user interfaces deployed over several operating systems and media. Mixed with Java this "intelligence" benefits from all of the design characteristics of this language like platform independent, security, type safety, exception handling, and so on, to create such tools as servers for diagnosing problems, spider and robot applications that transparently wander the net, mobile intelligent agents attending requests from other reasoning agents, human or not. One of the primary objectives, though, intended to be achieved is to integrate a full blown, ISO Prolog compliant, open source Prolog with the many IDES and tools in the Java momentum.

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35

Inagaki, Yasuyoshi, Nobuo Kawaguchi y Yohei Iwasaki. "Touch-and-Connect: A Connection Request Framework for Ad-hoc Networks and the Pervasive Computing Environment". IEEE, 2003. http://hdl.handle.net/2237/15454.

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Papapanagiotou, Eftychios [Verfasser], Fritz [Akademischer Betreuer] Busch, Constantinos [Gutachter] Antoniou, Larry [Gutachter] Head y Fritz [Gutachter] Busch. "Data Fusion in Sporadic Connected Environments for Urban Traffic Control / Eftychios Papapanagiotou ; Gutachter: Constantinos Antoniou, Larry Head, Fritz Busch ; Betreuer: Fritz Busch". München : Universitätsbibliothek der TU München, 2021. http://d-nb.info/123741329X/34.

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37

Dieterich, Matthew C. (Matthew Clayton) 1968. "Emerging options in project delivery and finance : Tren Urbano and Massport's intermodal transit connector". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/10030.

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38

Al-Enezi, F. Q. "Optimal cost versus efficiency configuration of a grid-connected photovoltaic system exploiting the weighted-sum method with focus on Kuwaiti National Grid". Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/379244/.

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An overview of the production and consumption of Kuwait electrical energy, installed capacity and peak loads is presented in this research. The results show that Kuwait has a serious problem because of insufficient electrical energy installed and load peaking, which is considered unacceptable. The research also identifies and analyses the geographical and temporal variability of solar energy inside Kuwait. The fundamental solar models are modified to estimate and identify daily and hourly global (direct-beam) and total solar radiation (SR) on horizontal surfaces on the basis of the more readily available meteorological data such as latitude angle, longitude angle, clearness index, solar time and corresponding hour angle. The presented results demonstrate that Kuwait has an abundance of solar energy capability in terms of almost cloudless atmosphere for nine months and twelve hours solar time a day throughout the year. The daily global and monthly averaged solar intensity have been computed. This research shows that the knowledge of SR data is essential for design and sizing of the photovoltaic (PV) systems. A specific type of PV module has been modelled and its characteristics such as I-V and P-V curves for each month of the year have been calculated and analysed using MATLAB/Simulink to determine the amount of DC current, voltage and power. These results form the basis of the grid-connected PV system (GCPV) design from array construction to the reliability of electrical supply. A technical sizing procedure based on sizing algorithm using iterative manual approach (SAIMA) for meeting specific amount of GWh output required by a potential PV system sponsor in Kuwait is presented. SAIMA has been implemented to determine the configuration of the PV array, inverter-to-PV array sizing factor and efficiency of the system according to previous PV module and inverter database. A novel methodology for approximating Pareto front multi-criteria cost-efficiency optimization problem for a proposed GCPV system has been constructed using system planning constraints. The proposed algorithm is based on bi-objective weighted-sum (BoWS) method to maximize the system efficiency and minimize the system cost. A main objective function of both GCPV system cost and efficiency has been stated as function of PV output power and inverter rated power. The proposed function is performed with the Sequential Quadratic Programing (SQP). The results presented in this research have been acquired through simulation of the proposed GCPV to a specific section of Alsabyia generation station part of Kuwait national grid with efficient maximum power point tracking (MPPT) algorithm incorporated into a DC-DC boost converter. The simulations were performed using Power Simulation Software (PSIM). The analytical model of the PV module has been combined with a ‘perturb and observe’ (P&O) method so that MPP is achieved with the external temperature and SR also considered. An inverter is used to track the output voltage of the converter and interface the PV array with the grid. The results show that the model not only achieves the MPP function but also improves the output of the inverter by reducing the ripples in the sine waveforms. Moreover, this research involved using the software package ERACS to analyze the impact of penetrating approximately 100 MW of the proposed PV generation to a part of the generation unit at Alsybia electrical station in Kuwait. The one-line diagram of the network was modeled in ERACS and it’s used to conduct power flow and fault studies. Four network locations were chosen as potential sites to connect the PV system. Power flow studies were conducted on the network for every hour that the PV array contributed power to the network and for 35 different network configurations for each daylight hour. Computer programs were created to conduct all of these power flow studies and to help analyze the data. Fault studies were then carried out on the network, with the PV array connected at all of the potential locations. There were a few faults that caused a fault level greater than 40 kA to flow through the 13.8 kV busbars.

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39

Sullivan, Terence. "Genes - just how important are they? weighing the causal importance of genes and environment in development". Saarbrücken VDM Verlag Dr. Müller, 2007. http://www.library.wisc.edu/databases/connect/dissertations.html.

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40

Beach, Nathan V. "Systems architecture of a sea base surface connector system in a 2020 humanitarian assistance/disaster relief joint operational environment". Thesis, Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/5130.

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41

Ro, Kyoungsoo. "Two-Loop Controller for Maximizing Performance of a Grid-Connected Photovoltaic-Fuel Cell Hybrid Power Plant". Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30378.

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The study started with the requirement that a photovoltaic (PV) power source should be integrated with other supplementary power sources whether it operates in a stand-alone or grid-connected mode. First, fuel cells for a backup of varying PV power were compared in detail with batteries and were found to have more operational benefits. Next, maximizing performance of a grid-connected PV-fuel cell hybrid system by use of a two-loop controller was discussed. One loop is a neural network controller for maximum power point tracking, which extracts maximum available solar power from PV arrays under varying conditions of insolation, temperature, and system load. A real/reactive power controller (RRPC) is the other loop. The RRPC meets the system's requirement for real and reactive powers by controlling incoming fuel to fuel cell stacks as well as switching control signals to a power conditioning subsystem. The RRPC is able to achieve more versatile control of real/reactive powers than the conventional power sources since the hybrid power plant does not contain any rotating mass. Results of time-domain simulations prove not only effectiveness of the proposed computer models of the two-loop controller, but also their applicability for use in transient stability analysis of the hybrid power plant. Finally, environmental evaluation of the proposed hybrid plant was made in terms of plant's land requirement and lifetime CO2 emissions, and then compared with that of the conventional fossil-fuel power generating forms.
Ph. D.

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42

Boston, Julie. "Learning in a digitally connected classroom: Secondary science teachers’ pedagogical reasoning and practices". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2019. https://ro.ecu.edu.au/theses/2275.

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Despite decades of research surrounding Information Communication Technology (ICT) use in schools, the pedagogical reasoning required to provide meaningful ICT enabled learning opportunities is rarely analysed in the literature. The purpose of this research was therefore to investigate teachers’ pedagogically reasoned practice. This study involved three exemplary Australian secondary science teachers, renowned for their expertise in utilising ICT working in classrooms where students had school issued one-to-one computers and reliable network access. The research utilised qualitative methods, including semistructured interviews, video-based observational data, and an array of lesson artefacts. The study followed a naturalistic multiple-case study design to explore the pedagogical reasoning and actions of these science teachers. The study identified different forms of pedagogical reasoning and action for a digitally connected world. Many aspects of this iterative model bear close resemblance to Shulman’s (1987) original conception of pedagogical reasoning and action. In each case, sophisticated reasoned decision-making drawing upon a range of teacher knowledge bases, most notably technological pedagogical content knowledge took place. The pedagogical reasoning and action model presented demonstrates a backward mapping approach where the use of ICT was directed at supporting the development of scientific content and educational outcomes of the mandated science curriculum. The research also found that these teachers held social constructivist beliefs for the use of ICT and intentionally designed ICT enabled opportunities from a learning affordance perspective. The research also demonstrated a reflexive relationship between the teacher’s beliefs and their pedagogical practices. Teacher activity involved significant preparatory work in the selection and curation of motivating, authoritative and multimodal Internet accessible ICT resources and tools aligned to the mandated science curriculum. In each case, the teachers had purposefully created a customised classroom online presence or website, offering students a flexible learning environment, an uncommon practice at the time of the study. The teachers designed ICT enabled learning opportunities following a guided inquiry model, frequently involving collaborative problem-based strategies. In each case, the students were the dominant users of ICT in the classroom using ICT for discovering knowledge, constructing knowledge and for sharing knowledge. The teachers’ role was predominantly one of orchestration of the learning environment, scaffolding and questioning students as they engaged with guided inquiry-based learning tasks. Ultimately the research revealed the critical role of the teacher in mediating the affordances of ICT for meaningful learning. Overall the findings offer useful insights into how exemplary science teachers’ reason and act about the use of ICT in a digitally connected classroom. An important implication for the development of initial science teacher education programs arose from the study, notably that preservice teachers require ongoing and authentic course opportunities to support the development of the technology, pedagogy, and content knowledge relevant for a digitally connected classroom.

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43

Wilson, Jason Clifford. "A techno-economic environmental approach to improving the performance of PV, battery, grid-connected, diesel hybrid energy systems : A case study in Kenya". Thesis, Högskolan Dalarna, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:du-28542.

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Backup diesel generator (DG) systems continue to be a heavily polluting and costly solution for institutions with unreliable grid connections. These systems slow economic growth and accelerate climate change. Photovoltaic (PV), energy storage (ES), grid connected, DG – Hybrid Energy Systems (HESs) or, PV-HESs, can alleviate overwhelming costs and harmful emissions incurred from traditional back-up DG systems and improve the reliability of power supply. However, from project conception to end of lifetime, PV-HESs face significant barriers of uncertainty and variable operating conditions. The fit-and-forget solution previously applied to backup DG systems should not be adopted for PV-HESs. To maximize cost and emission reductions, PV-HESs must be adapted to their boundary conditions for example, irradiance, temperature, and demand. These conditions can be defined and monitored using measurement equipment. From this, an opportunity for performance optimization can be established. The method demonstrated in this study is a techno-economic and environmental approach to improving the performance of PV-HESs. The method has been applied to a case study of an existing PV-HES in Kenya. A combination of both analytical and numerical analyses has been conducted. The analytical analysis has been carried out in Microsoft Excel with the intent of being easily repeatable and practical in a business environment. Simulation analysis has been conducted in improved Hybrid Optimization by Genetic Algorithms (iHOGA), which is a commercially available software for simulating HESs. Using six months of measurement data, the method presented identifies performance inefficiencies and explores corrective interventions. The proposed interventions are evaluated, by simulation analyses, using a set of techno-economic and environment key performance indicators, namely: Net Present Cost (NPC), generator runtime, fuel consumption, total system emissions, and renewable fraction. Five corrective interventions are proposed, and predictions indicate that if these are implemented fuel consumption can be reduced by 70 % and battery lifetime can be extended by 28 %, net present cost can be reduced by 30 % and emissions fall by 42 %. This method has only been applied to a single PV-HES; however, the impact this method could have on sub-Saharan Africa as well as similar regions with unreliable grid connections is found to be significant. In the future, in sub-Saharan Africa alone, over $500 million dollars (USD) and 1.7 billion kgCO2 emissions could be saved annually if only 25 % of the fuel savings identified in this study were realized. The method proposed here could be improved with additional measurement data and refined simulation models. Furthermore, this method could potentially be fully automated, which could allow it to be implemented more frequently and at lower cost.

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44

Black, Brian C., Laura H. Bollock, Sinene Bouabid, Michael A. Glova, Jason A. Hall, Glynn M. Harden, Curtis J. Hickle et al. "Sea TENTACLE: Track, Engage, & Neutralize Threats - Asymmetric & Conventional - in the Littoral Environment". Thesis, Monterey, California : U.S. Naval Postgraduate School, 2006. http://hdl.handle.net/10945/7275.

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Includes supplementary material.
Sea TENTACLE is a proposed afloat platform whose primary mission is to utilize the state-of-the-art technology of unmanned vehicles to monitor and neutralize all subsurface enemy threats in the littorals. This mission can be specified further as anti-submarine warfare, mine warfare and maritime surveillance. The design philosophy of Sea TENTACLE embodies the ideal of providing a multi-mission capable sea frame extending network-centric warfare into the littorals. The design goals of the TSSE team were first to develop a platform to deploy, recover, and maintain unmanned vehicle (e.g. UUVs, USVs, UAVs) and second to enableto ship to act as an afloat network operations center for distributed assets. Allowing all units to work together seamlessly to conduct focused missions in the littorals makes the Sea TENTACLE a creitical component within the network-centric environment. The versatility of its cargo hold and modular design allows Sea TENTACLE to be outfitted dynamically to complete a veriety of secondary missions including humanitarian aid, salvage and spacial operations support. Sea TENTACLE's combat management and operations system will employ the Enterprise architecture design enabling C4ISR capabilities that will meet emerging network centric warfare needs.

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45

Liu, Lollo. "Life Cycle Assessment of a Lithium-Ion Battery pack for Energy storage Systems : - the environmental impact of a grid-connected battery energy storage system". Thesis, Uppsala University, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-428627.

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This thesis assessed the life-cycle environmental impact of a lithium-ion battery pack intended for energy storage applications. A model of the battery pack was made in the life-cycle assessment-tool, openLCA. The environmental impact assessment was conducted with the life-cycle impact assessment methods recommended in the Batteries Product Environmental Footprint Category Rules adopted by the European Commission (2016). The findings in this study showed that the most important parameter in the cradle-to-grave assessment was the use-stage losses, which can be reduced by using electricity grids with high sharesof renewable energy or by increase the round-trip efficiency of the battery system. However, for the cradle-to-gate assessment, five impact categories were found to be relevant. These categories were: climate change, acidification, fossil resource use, resource use (minerals and metals) and particulate matter. Furthermore, within these impact categories, four materials contributed to more than 65 % of all impact. These key materials were; nickel, aluminium, cobalt and graphite. Therefore, a recommendation to battery manufacturers is to prioritise sourcing these four key materials from sustainable suppliers to reduce the overall cradle-to-gate environmental impact. Lastly, by integrating recycling of the battery pack in the end-of-life-stage, it was possibleto achieve a net reduction of 9-20 % of the cradle-to-grave climate change, acidification and fossil resource use compared to not including recycling. Therefore, the development of efficient and large-scale recycling will likely play a major role in reducing the environmental impact from lithium-ion batteries in the future.

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46

"Sensors and Their Applications for Connected Health and Environment". Doctoral diss., 2018. http://hdl.handle.net/2286/R.I.51613.

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abstract: Connected health is an emerging field of science and medicine that enables the collection and integration of personal biometrics and environment, contributing to more precise and accurate assessment of the person’s state. It has been proven to help to establish wellbeing as well as prevent, diagnose, and determine the prognosis of chronic diseases. The development of sensing devices for connected health is challenging because devices used in the field of medicine need to meet not only selectivity and sensitivity of detection, but also robustness and performance under hash usage conditions, typically by non-experts in analysis. In this work, the properties and fabrication process of sensors built for sensing devices capable of detection of a biomarker as well as pollutant levels in the environment are discussed. These sensing devices have been developed and perfected with the aim of overcoming the aforementioned challenges and contributing to the evolving connected health field. In the first part of this work, a wireless, solid-state, portable, and continuous ammonia (NH3) gas sensing device is introduced. This device determines the concentration of NH3 contained in a biological sample within five seconds and can wirelessly transmit data to other Bluetooth enabled devices. In this second part of the work, the use of a thermal-based flow meter to assess exhalation rate is evaluated. For this purpose, a mobile device named here mobile indirect calorimeter (MIC) was designed and used to measure resting metabolic rate (RMR) from subjects, which relies on the measure of O2 consumption rate (VO2) and CO2 generation rate (VCO2), and compared to a practical reference method in hospital. In the third part of the work, the sensing selectivity, stability and sensitivity of an aged molecularly imprinted polymer (MIP) selective to the adsorption of hydrocarbons were studied. The optimized material was integrated in tuning fork sensors to detect environmental hydrocarbons, and demonstrated the needed stability for field testing. Finally, the hydrocarbon sensing device was used in conjunction with a MIC to explore potential connections between hydrocarbon exposure level and resting metabolic rate of individuals. Both the hydrocarbon sensing device and the metabolic rate device were under field testing. The correlation between the hydrocarbons and the resting metabolic rate were investigated.
Dissertation/Thesis
Doctoral Dissertation Chemical Engineering 2018

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47

CHEN, YU-YING y 陳昱穎. "Research of Motion Capture in Network Connected Virtual Reality Environment". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/p6s48y.

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碩士
銘傳大學
資訊傳播工程學系碩士班
106
This article presents a virtual reality (VR) motion capture system for Multi-player chat, usually there are amounts of sensors for motion capture (above 10 sensors), it's not realistic to replace them with an equal number of Vive Trackers. To rule this problem out, Inverse Kinematics (IK) can be used to calculate angles of skeleton and then reduce the number of trackers without loss of accuracy. In the other hand, the article also offers a motion recording and replay function, customers can record a body motion clip and send it to others via the Internet. The function can not only be applied to the multi-player social chat, but it also can be used in body movement training or medical treatment. For example, if the patient can't go to hospital to do physical rehabilitation because of the traffic issue, physiotherapist can record the motion of physical rehabilitation and send to the patient for training.

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Lin, Cheng-Feng y 林正峰. "Optimizing the Number of Connected Devices in the Industrial WiFi Environment". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/juks4v.

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碩士
國立臺灣大學
電信工程學研究所
105
With the rise of the industry 4.0, the factory is moving towards automation through the use of sensors, data collection and analysis. How to deploy just a limited number of access points and still optimize the number of devices meeting QoS devices in the factory has become an important technique. Due to the fact that each device has different QoS requirement, this research will divide devices into two groups based on the difference of their QoS requirements. One group is for high throughput devices which have a higher traffic demand, another is for delay sensitive devices which have a more strict latency requirement. According to device mobility, we name the high throughput device with fixed position as primary device 1, the delay sensitive device with fixed position as primary device 2, and call mobile high throughput device the secondary device. And we then analyze the QoS and coverage ratio of these types of devices. In order to increase the number of devices meeting QoS requirements. We use NS-3 to simulate how an access point serves devices with two different kinds of QoS requirements, and we observed the change between number of devices meeting QoS requirement.We found if an access point only serves one kind of devices with the same QoS requirement, it can support more devices meeting QoS requirement. We also divide the interference range into effective transmission interference range and invalid transmission interference range. Using NS-3 we are able to simulate the influence caused by two kinds of interference. Through these experiments, we then design our AP deployment algorithm. We use the graph coloring algorithm with maximum degree first and the Improved Priority Based Coloring Algorithm to implement channel allocation. In order to decrease the interference between access points, we consider the influence caused by either co-channel or adjacent-channel interferences. And then we select those channels which will not experience co-channel or adjacent-channel interferences in the priority list. As a result, we can enhance spectrum usage significantly. Finally, we simulate different factory situations and compare the result of AP deployments with different algorithms. Among them, our AP deployment algorithm can cover more primary devices and assure that more primary devices can meet their QoS requirements. Our AP deployment algorithm also can make the ratio of network coverage between APs and secondary devices at the required level and has better adaptability.

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Shu, Hsin-Hwa y 徐世華. "The Maintenance of Data Update Logs in an Intermittently Connected Environment". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/76405732336944651897.

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碩士
國立成功大學
會計學系碩博士班
92
This research addresses the problem of efficiently managing and maintaining update logs in an intermittently connected environment. Such update logs contain updates done to shared data when clients disconnect. These updates must be made known to other clients that use shared data. Typically, update logs are prepared by server, and are transmitted when a client connects. Our research considers ways to simplify these logs so as to save storage and reduce transmission time. We make use of algebraic rules to perform the simplification. Via commutative and simplifying rules, we reduce operations in these logs. We also present a data-centric approach which clusters data into groups, and assign one or more of these groups to each client. As a result, server only needs to prepare one update file for each group, thereby reducing server workload and improving system scalability.

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50

Giri, Sourav Kumar y Rajeeb Kumar Panigrahi. "Crash Fault Identification of a A K-Connected Network in Static Fault Environment". Thesis, 2009. http://ethesis.nitrkl.ac.in/379/1/crash_fault_identification_of_a_k-connected_network.pdf.

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The problem of distributed diagnosis in the presence of dynamic failures and repairs is considered. To address this problem, the notion of bounded correctness is defined. Bounded correctness is made up of three properties: bounded diagnostic latency, which ensures that information about state changes of nodes in the system reaches working nodes with a bounded delay, bounded start-up time, which guarantees that working nodes determine valid states for every other node in the system within bounded time after their recovery, and accuracy, which ensures that no spurious events are recorded by working nodes. It is shown that, in order to achieve bounded correctness, the rate at which nodes fail and are repaired must be limited. This requirement is quantified by defining a minimum state holding time in the system. Algorithm HeartbeatComplete is presented and it is proven that this algorithm achieves bounded correctness in fully-connected systems while simultaneously minimizing diagnostic latency, start-up time, and state holding time. A diagnosis algorithm for arbitrary topologies, known as Algorithm ForwardHeartbeat, is also presented.ForwardHeartbeat is shown to produce significantly shorter latency and state holding time than prior algorithms, which focusedprimarily on minimizing the number of tests at the expense of latency.

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