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Ανάπτυξη συστημάτων διαχείρισης κυκλοφορίας και αυτοματισμοί υποστηρικτικών υποσυστημάτων στον αυτοκινητόδρομο Κόρινθος-Τρίπολη-ΚαλαμάταΨώνης, Θεόδωρος, Δερβιτσιώτης, Χαράλαμπος 16 June 2011 (has links)
Η παρούσα διπλωματική εργασία πραγματεύεται την ανάπτυξη συστημάτων διαχείρισης κυκλοφορίας και αυτοματισμών υποστηρικτικών υποσυστημάτων στον αυτοκινητόδρομο Κόρινθος-Τρίπολη-Καλαμάτα. Αρχικά γίνεται μια ιστορική αναδρομή των αυτοκινητοδρόμων και των αλγορίθμων ανίχνευσης συμβάντων, ώστε να γίνει αντιληπτός ο σκοπός και οι απαιτήσεις που επιβάλλουν τη κατασκευή ενός τέτοιου έργου. Εν συνεχεία γίνεται αναφορά των γενικών στοιχείων του συγκεκριμένου αυτοκινητοδρόμου. Περιγράφεται αναλυτικά ο ηλεκτρονικός και μηχανολογικός εξοπλισμός που θα χρησιμοποιηθεί για το σύστημα διαχείρισης κυκλοφορίας (TMS) και το SCADA, ώστε να είναι δυνατή η καλύτερη εποπτεία-διαχείρηση του αυτοκινητοδρόμου. Επίσης, περιγράφεται ο εξοπλισμός PLC-λογισμικού που θα χρησιμοποιηθεί. Ακολουθεί παρουσίαση του συστήματος αερισμού των σηράγγων καθώς θεωρούνται το βασικότερο σημείο ελέγχου. Εν συνεχεία , αναλύονται οι αυτοματισμοί υποσυστημάτων (πυρασφάλεια, άρδευσης, φωτισμού σήραγγας και εξαερισμός σήραγγας) καθώς επίσης και το SCADA. Ένα ακόμη σημαντικό κομμάτι της παρούσας εργασίας είναι η ανάλυση του συστήματος διαχείρισης της κυκλοφορίας (TMS) και η συνύπαρξή του με το SCADA. Τέλος, περιγράφονται δύο αλγόριθμοι ανίχνευσης συμβάντων, που πρόκειται ωα χρησιμοποιηθούν στο έργο, ο California No7 και ο DES καθώς η υλοποίηση τους. / The present thesis discusses the development of traffic management systems and controls supporting subsystems which is going to be implemented on the highway Corinth-Tripoli-Kalamata. Firstly, the history of motorways and event detection algorithms is presented so that the purpose and the requirements imposing the construction of such a project to be understood. Furthermore, it refers to the general elements of the motorway. Moreover, the electronic and mechanical equipment are described in detail that will be used for traffic management system (TMS) and SCADA, in order to be managed the better monitoring- management of the highway. Also, it is depicted the equipment PLC-software which will be used. It is following the presentation of the ventilation system of tunnels as tunnels are considered the main checkpoint. Afterwards, automation subsystems (fire protection, irrigation, lighting and tunnel ventilation tunnel) are exposed as well as SCADA. Another important part of this study is the analysis of the traffic management system (TMS) and its coexistence with the SCADA. Finally, the two algorithms of event detection, which will be used in the project, the California No7 and DES and their implementation, are presented.
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Traffic Engineering using Multipath Routing ApproachesMazandu, Gaston Kuzamunu 12 1900 (has links)
Thesis (MSc (Mathematical Sciences. Computer Science))--University of Stellenbosch, 2007. / It is widely recognized that Traffic engineering (TE) mechanisms have to be added to the IP
transport functionalities to provide QoS guarantees while ensuring efficient use of network
resources. Traffic engineering is a network management technique which routes traffic to
where bandwidth is available in the network to achieve QoS agreements between current
and future demands and the available network resources. Multi-path routing has been
proven to be a more efficient TE mechanism than Shortest Path First (SPF) routing in
terms of proffit maximization and resource usage optimization. However the identiffication
of set of paths over which traffic is forwarded from source to the destination and the
distribution of traffic among these paths are two issues that have been widely addressed
by the IP community but remain an open issue for the emerging generation IP networks.
Building upon different frameworks, this thesis revisits the issue of multi-path routing to
present and evaluate the performance of different traffic splitting mechanisms to achieve
QoS routing in Multi-Protocol Label Switching (MPLS) and Wireless Sensor Networks
(WSNs). Three main contributions are identified in this thesis. First, we extend an optimization
model that used the M/M/1 queueing model on a simple network consisting
of a single source-destination pair by using the M/M/s queueing model on a general network
consisting of several source-destination pairs. The model solves a multi-path routing
problem by defining a Hamiltonian as a function of delay incurred and subjecting this
Hamiltonian to Pontryagin's cost minimization to achieve efficient diffusion of traffic over
the available parallel paths. Second, we revisit the problem of cost-based optimization in
a multi-path setting by using a Game theoretical framework to propose and evaluate the
performance of competitive and cooperative multi-path routing schemes and the impact of
the routing metric (cost) on the difference between these two schemes. Finally, building upon a previously proposed optimization benchmark, we propose an Energy constrained
QoS routing scheme for Wireless Sensor Networks and show through simulation that our
scheme outperforms the benchmark scheme.
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Nouvelles méthodes de collecte des données de trafic : nouveaux enjeux pour les gestionnaires de voirie / New ways to collect traffic data : new challenges for road network authoritiesCharansonney, Luc 30 May 2018 (has links)
Le trafic routier évolue dans un contexte qui a connu trois changements majeurs ces deux dernières décennies : changement politique tout d'abord, avec la remise en cause de la place jusque-là occupée par la voiture en ville ; changement technologique ensuite, par lequel tant le véhicule que son conducteur produisent et reçoivent des données indépendamment des infrastructures de gestion du gestionnaire ; changement financier enfin, alors que les systèmes de gestion du trafic sont très dépendants de finances publiques de plus en plus contraintes.Dans ce contexte, l'auteur, du fait de ses fonctions, adopte le point de vue d'un gestionnaire de voirie clé, la Ville de Paris. En charge de l'évaluation des conséquences techniques des politiques de circulation sur l'écoulement du trafic motorisé, il s'intéresse ici à la manière dont les nouvelles données de trafic renouvellent la connaissance technique du gestionnaire sur la demande.Pour ce faire, l'auteur montre d'abord que les données de trafic et l'information trafic ont toujours été au cœur des préoccupations du gestionnaire. Données et information sont profondément liées à la technologie disponible et aux missions mêmes du gestionnaire. Les développements théoriques, alimentés par les données, tentent ainsi de lier les technologies avec les missions du gestionnaire.Ensuite, à travers l'évaluation technique de politiques de circulation (fermetures de voie, réduction de la vitesse limite) sur la base de deux types de nouvelles données (vitesses GPS et temps de parcours Bluetooth), l'auteur analyse les caractéristiques de ces jeux de données, les résultats auxquels ils permettent de parvenir, et la manière dont ils complètent la connaissance tirée des capteurs fixes historiques. Ces nouveaux jeux de données permettent au gestionnaire d'obtenir une connaissance de la demande du point de vue des usagers, alors que les capteurs fixes fournissent principalement un point de vue collectif de flux. Cette richesse nouvelle d'information redéfinit les schémas de décision du gestionnaire de voirie / Road traffic evolves in a context which has undergone three major changes in the past two decades: first, a political change, reshaping the car's role in cities; second, a technical change, through which both vehicles and drivers emit and receive information independently of road authorities' roadside infrastructure; and finally, a financial change, as traffic management infrastructure has heavily relied on public funding which now becomes scarcer.From the perspective of a key road authority, the City of Paris, the Author, in charge of assessing the impact on traffic flow of major disruptive policies, addresses how new traffic data renews the road authority's knowledge of the traffic, on technical grounds.The Author has worked on Bluetooth travel-time and GPS based Floating Car Data datasets. He believes he makes two major contributions in the field.He first shows that traffic data and traffic information have always been at the core of the road authority's concerns, deeply related to the available technology, the missions of the road authority, and the theory attempting to bridge the gap between the two.Through the technical assessment of traffic-related policies (road closures, speed-limit reduction), based on two types of new traffic data (GPS speeds and Bluetooth travel-times), the Author analyzes the characteristics of the two datasets, the results they yield and how they complement legacy fixed-sensor based data. They allow the road authority to grasp user-perspective information whereas legacy data mostly offered a collective flow perspective. This, in turn, reshapes the decision-making process of road authorities
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Dispečerské řízení kamionů při cestách do zahraničí / Supervisory control truck when traveling abroadPAVLASOVÁ, Hana January 2010 (has links)
The main objective of this study was to analyze the supervisory control of the company STTRANS, focusing on transportation dispatcher job within a week and watch how they governed and navigating assigned trucks. Own observation or interviews with the dispatcher or the Head of Division I examined the information that I needed for further work. I have defined the tasks of the truck and I watched them work. Dispatcher can thanks to modern technology to monitor the movement of all assigned vehicles. Their movements are creating records that will allow me, through data processing and computer technology to re-compare the activities of all tracked vehicles. Based on the gathered data, I replied to the hypotheses and propose measures on possible improvements.  To expand its business in the transport of materials and fluids in order to receive orders to load more characters than ever before.  assigned to the truck instead of two drivers and one that could increase firm performance.  reach more potential customers, which could offer a quality service.  More care to monitor mileage of drivers, they all have a chance at achieving a comparable level of monthly salary.  Reallocate always a dispatcher for the afternoon shift, which would address the problem of drivers on the road, and the dispatcher would not have to work to solve problems in their personal leisure. Výledků The analysis showed that currently paid to implement the company standards of quality standards.
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Gerenciamento ativo de tráfego : estudo de caso de uma autoestrada brasileiraCaleffi, Felipe January 2013 (has links)
Esta dissertação apresenta uma análise da modelagem de estratégias de gerenciamento ativo de tráfego para um estudo de caso de uma autoestrada brasileira. O gerenciamento ativo de tráfego busca de uma forma eficiente melhorar as condições do tráfego durante horários e locais mais congestionados. Esta abordagem consiste em uma combinação de estratégias que aperfeiçoam a operação da infraestrutura existente. Esta dissertação é composta de três artigos, nos quais são apresentados: (i) as tendências atuais de gerenciamento ativo de tráfego, discutindo seus propósitos, definições, benefícios e tendências em novos projetos, (ii) uma análise dos dados coletados no trecho em estudo, que servem de base para a calibração e validação do modelo de simulação, (iii) calibração no software VISSIM do segmento de autoestrada estudado para reproduzir os comportamentos observados em campo, incluindo as velocidades, parâmetros de car following e de troca de faixas e (iv) uma avaliação e quantificação da eficácia da modelagem das estratégias de gerenciamento ativo de tráfego para o trecho em estudo. A calibração do modelo foi um estágio importante da modelagem, pois o trecho modelado possui características especiais quanto ao comportamento do tráfego. Assim, o simular não é capaz de reproduzir naturalmente o trecho em estudo com seus parâmetros default, fazendo-se necessário um esforço de calibração para representar de forma satisfatória as características presentes na rodovia. O tempo de headway e a distância mínima entre os veículos, a agressividade nas trocas de faixa, e nas acelerações e desacelerações foram os parâmetros com maior influência na modelagem. Dados coletados através de filmagens e de coletores com laços indutivos foram usados para calibrar e validar o modelo de simulação. As estratégias de gerenciamento ativo de tráfego empregadas na simulação foram a de harmonização da velocidade e a do uso temporário do acostamento. A modelagem demonstrou que o gerenciamento ativo de tráfego tem impactos positivos na operação do tráfego. Redução de headways, redução nos tempos médios de viagem, na variabilidade dos tempos de viagem e no número de trocas de faixa foram benefícios mensurados. Com o uso das estratégias houve também redução do tempo em que o fluxo da via permanece em colapso, aumentando a eficiência do trecho. / This paper presents an analysis of modeling strategies for active traffic management to a case study of a Brazilian highway. The active traffic management search for an efficient way to improve traffic conditions during the most congested times and locations. This approach consists of a combination of strategies that improve the operation of existing infrastructure. This dissertation consists of three articles in which they are presented: (i) the current trends of active traffic management, discussing its purpose, definitions, benefits and trends in new projects, (ii) an analysis of data collected in the stretch under study, serving as a basis for calibration and validation of the simulation model, (iii) calibration of the VISSIM software for a studied freeway segment to reproduce the behaviors observed in the field, including speeds, car following parameters and lane changes and ( iv) an assessment and quantification of the effectiveness of modeling strategies for active traffic management to the stretch under study. The calibration of the model was an important stage of the modeling, because the modeled stretch has special characteristics as the traffic behavior. Thus, the simulator is not able to naturally simulate the performance under study with its default parameters, making it necessary a calibration effort to represent satisfactorily the features present on the highway. The headway time and the minimum distance between vehicles, aggressiveness in lane changes, and the acceleration and deceleration parameters were most influential in the model. Data collected through filming and collectors with inductive loops were used to calibrate and validate the simulation model. The active traffic management strategies assets employed in the simulation were the speed harmonization and temporary hard shoulder use. The modeling showed that the active traffic management has a positive impact on traffic operation. Reducing headways, reduction in average travel time, variability in travel times and the number of lane changes were measured benefits. With the use of strategies were also reduces the time in which the flow pathway remains collapsed, increasing the efficiency of the stretch.
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Gerenciamento ativo de tráfego : estudo de caso de uma autoestrada brasileiraCaleffi, Felipe January 2013 (has links)
Esta dissertação apresenta uma análise da modelagem de estratégias de gerenciamento ativo de tráfego para um estudo de caso de uma autoestrada brasileira. O gerenciamento ativo de tráfego busca de uma forma eficiente melhorar as condições do tráfego durante horários e locais mais congestionados. Esta abordagem consiste em uma combinação de estratégias que aperfeiçoam a operação da infraestrutura existente. Esta dissertação é composta de três artigos, nos quais são apresentados: (i) as tendências atuais de gerenciamento ativo de tráfego, discutindo seus propósitos, definições, benefícios e tendências em novos projetos, (ii) uma análise dos dados coletados no trecho em estudo, que servem de base para a calibração e validação do modelo de simulação, (iii) calibração no software VISSIM do segmento de autoestrada estudado para reproduzir os comportamentos observados em campo, incluindo as velocidades, parâmetros de car following e de troca de faixas e (iv) uma avaliação e quantificação da eficácia da modelagem das estratégias de gerenciamento ativo de tráfego para o trecho em estudo. A calibração do modelo foi um estágio importante da modelagem, pois o trecho modelado possui características especiais quanto ao comportamento do tráfego. Assim, o simular não é capaz de reproduzir naturalmente o trecho em estudo com seus parâmetros default, fazendo-se necessário um esforço de calibração para representar de forma satisfatória as características presentes na rodovia. O tempo de headway e a distância mínima entre os veículos, a agressividade nas trocas de faixa, e nas acelerações e desacelerações foram os parâmetros com maior influência na modelagem. Dados coletados através de filmagens e de coletores com laços indutivos foram usados para calibrar e validar o modelo de simulação. As estratégias de gerenciamento ativo de tráfego empregadas na simulação foram a de harmonização da velocidade e a do uso temporário do acostamento. A modelagem demonstrou que o gerenciamento ativo de tráfego tem impactos positivos na operação do tráfego. Redução de headways, redução nos tempos médios de viagem, na variabilidade dos tempos de viagem e no número de trocas de faixa foram benefícios mensurados. Com o uso das estratégias houve também redução do tempo em que o fluxo da via permanece em colapso, aumentando a eficiência do trecho. / This paper presents an analysis of modeling strategies for active traffic management to a case study of a Brazilian highway. The active traffic management search for an efficient way to improve traffic conditions during the most congested times and locations. This approach consists of a combination of strategies that improve the operation of existing infrastructure. This dissertation consists of three articles in which they are presented: (i) the current trends of active traffic management, discussing its purpose, definitions, benefits and trends in new projects, (ii) an analysis of data collected in the stretch under study, serving as a basis for calibration and validation of the simulation model, (iii) calibration of the VISSIM software for a studied freeway segment to reproduce the behaviors observed in the field, including speeds, car following parameters and lane changes and ( iv) an assessment and quantification of the effectiveness of modeling strategies for active traffic management to the stretch under study. The calibration of the model was an important stage of the modeling, because the modeled stretch has special characteristics as the traffic behavior. Thus, the simulator is not able to naturally simulate the performance under study with its default parameters, making it necessary a calibration effort to represent satisfactorily the features present on the highway. The headway time and the minimum distance between vehicles, aggressiveness in lane changes, and the acceleration and deceleration parameters were most influential in the model. Data collected through filming and collectors with inductive loops were used to calibrate and validate the simulation model. The active traffic management strategies assets employed in the simulation were the speed harmonization and temporary hard shoulder use. The modeling showed that the active traffic management has a positive impact on traffic operation. Reducing headways, reduction in average travel time, variability in travel times and the number of lane changes were measured benefits. With the use of strategies were also reduces the time in which the flow pathway remains collapsed, increasing the efficiency of the stretch.
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Řízení letového provozu v Evropě / Air traffic management in Europe - Single European SkyŠyc, Petr January 2009 (has links)
Thesis analyses present status of air traffic management in European area from historical and legislative point of view. Subjects of thesis are present projects in ATM and future variants of organization of air traffic in EU. Practical part focuses on impact of ATM on air transportation.
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Analýza dopravných systémov v Dubline a Bratislave / Analysis of transportation systems in Dublin and BratislavaZávodská, Tatiana January 2009 (has links)
This thesis presents a comparison of the two urban systems in Dublin and Bratislava with regard to the organization of transport and traffic management, fleet composition and fare. Aims to show the different approaches to the concept of public transport and progression, which in recent years the city has achieved.
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Gerenciamento ativo de tráfego : estudo de caso de uma autoestrada brasileiraCaleffi, Felipe January 2013 (has links)
Esta dissertação apresenta uma análise da modelagem de estratégias de gerenciamento ativo de tráfego para um estudo de caso de uma autoestrada brasileira. O gerenciamento ativo de tráfego busca de uma forma eficiente melhorar as condições do tráfego durante horários e locais mais congestionados. Esta abordagem consiste em uma combinação de estratégias que aperfeiçoam a operação da infraestrutura existente. Esta dissertação é composta de três artigos, nos quais são apresentados: (i) as tendências atuais de gerenciamento ativo de tráfego, discutindo seus propósitos, definições, benefícios e tendências em novos projetos, (ii) uma análise dos dados coletados no trecho em estudo, que servem de base para a calibração e validação do modelo de simulação, (iii) calibração no software VISSIM do segmento de autoestrada estudado para reproduzir os comportamentos observados em campo, incluindo as velocidades, parâmetros de car following e de troca de faixas e (iv) uma avaliação e quantificação da eficácia da modelagem das estratégias de gerenciamento ativo de tráfego para o trecho em estudo. A calibração do modelo foi um estágio importante da modelagem, pois o trecho modelado possui características especiais quanto ao comportamento do tráfego. Assim, o simular não é capaz de reproduzir naturalmente o trecho em estudo com seus parâmetros default, fazendo-se necessário um esforço de calibração para representar de forma satisfatória as características presentes na rodovia. O tempo de headway e a distância mínima entre os veículos, a agressividade nas trocas de faixa, e nas acelerações e desacelerações foram os parâmetros com maior influência na modelagem. Dados coletados através de filmagens e de coletores com laços indutivos foram usados para calibrar e validar o modelo de simulação. As estratégias de gerenciamento ativo de tráfego empregadas na simulação foram a de harmonização da velocidade e a do uso temporário do acostamento. A modelagem demonstrou que o gerenciamento ativo de tráfego tem impactos positivos na operação do tráfego. Redução de headways, redução nos tempos médios de viagem, na variabilidade dos tempos de viagem e no número de trocas de faixa foram benefícios mensurados. Com o uso das estratégias houve também redução do tempo em que o fluxo da via permanece em colapso, aumentando a eficiência do trecho. / This paper presents an analysis of modeling strategies for active traffic management to a case study of a Brazilian highway. The active traffic management search for an efficient way to improve traffic conditions during the most congested times and locations. This approach consists of a combination of strategies that improve the operation of existing infrastructure. This dissertation consists of three articles in which they are presented: (i) the current trends of active traffic management, discussing its purpose, definitions, benefits and trends in new projects, (ii) an analysis of data collected in the stretch under study, serving as a basis for calibration and validation of the simulation model, (iii) calibration of the VISSIM software for a studied freeway segment to reproduce the behaviors observed in the field, including speeds, car following parameters and lane changes and ( iv) an assessment and quantification of the effectiveness of modeling strategies for active traffic management to the stretch under study. The calibration of the model was an important stage of the modeling, because the modeled stretch has special characteristics as the traffic behavior. Thus, the simulator is not able to naturally simulate the performance under study with its default parameters, making it necessary a calibration effort to represent satisfactorily the features present on the highway. The headway time and the minimum distance between vehicles, aggressiveness in lane changes, and the acceleration and deceleration parameters were most influential in the model. Data collected through filming and collectors with inductive loops were used to calibrate and validate the simulation model. The active traffic management strategies assets employed in the simulation were the speed harmonization and temporary hard shoulder use. The modeling showed that the active traffic management has a positive impact on traffic operation. Reducing headways, reduction in average travel time, variability in travel times and the number of lane changes were measured benefits. With the use of strategies were also reduces the time in which the flow pathway remains collapsed, increasing the efficiency of the stretch.
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An Entropy-based Low Altitude Air Traffic Safety Assessment FrameworkHsun Chao (11819519) 18 December 2021 (has links)
<div>The National Aeronautics and Space Administration (NASA) has a vision for Advanced Air Mobility (AAM) based on safely introducing aviation services to missions that were previously not served or under-served. Many potential AAM missions lie in metropolitan areas that are beset by various types of uncertainty and potential constraints. Radio interference from other electronic devices can render unreliable communication between flying vehicles to ground operators. Buildings have irregular surfaces that degrade GPS localization performance. Skyscrapers can induce spontaneous turbulence that degrades vehicles' navigational accuracy. However, the potential market demands for aerial passenger-carrying and package delivery services have attracted investments. For example, Google WingX, Amazon Prime Air, and Joby Aviation are well-known companies developing AAM systems and services. If the market visions are realized, how will safety be assessed and maintained with high-density AAM operations?</div><div><br></div><div>While there are multiple technology candidates for realizing high-density AAM operations in urban environments, the means to accomplish the requisite first step of assessing the airspace safety of an integrated AAM eco-system from the candidate technologies is crucial but as yet unclear. This dissertation proposes an entropy-based framework for assessing the airspace safety level for low-altitude airspace in an AAM setting. The framework includes a conceptual model for depicting the information flows between air vehicles and an air traffic authority (ATA) and the use of a probability distribution to represent the traffic state. Subsequently, the framework embeds three airspace-level metrics for assessing airspace safety and uncertainty levels. The traffic safety severity metric quantifies the traffic safety level. The traffic entropy quantifies the uncertainty level of the traffic state distribution. Finally, the temperature is the ratio of the traffic safety severity to the traffic entropy. The temperature is similar to the traffic safety severity but gives a higher weight to the instance with a safe traffic state. </div><div><br></div><div>Simulation studies show that the combined use of the three metrics can evaluate relative airspace safety levels even if the unsafe conditions do not occur. The use cases include using the metrics for real-time airspace safety level monitoring and comparing the design of airspace systems and operational strategies. Additionally, this study demonstrates using a heat map to visualize vehicle-level metrics and assess designs of UAM airspace structures. The contribution of this study includes two parts. First, the temperature metric can heuristically assess a probability function. Based on the definition of the cost function, the temperature metric gives a higher weighting to the instance of the probability function with a lower cost value. This study constructs several triggers for predicting if a near-miss event would happen in the airspace. The temperature-based trigger has a better prediction accuracy than the cost-function-based trigger. Secondly, the temperature can visualize the safety level of an airspace structure with the considerations of the environmental and vehicle state measurement uncertainty. The locations with high-temperature values indicate that the regions are more likely to have endangered vehicles. Although this framework does not provide any means of resolving the unsafe conditions, it can be powerful in the comparison of different airspace design concepts and identify the weaknesses of either airspace design or operational strategies. </div>
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