Pub Date : 2019-10-01DOI: 10.1109/DS-RT47707.2019.8958694
S. Hadiwardoyo, C. Calafate, Juan-Carlos Cano, K. Krinkin, Dmitry Klionskiy, Enrique Hernández-Orallo, P. Manzoni
Unmanned Aerial Vehicles (UAVs) can act as re-lays in areas with limited infrastructure to support car-to-car communications. Prior studies on UAV-to-car communications showed that the irregularity of the terrains has a significant impact on link quality. Thus, in this paper, we propose a positioning technique that relies on Particle Swarm optimization (PSO) to optimize the positioning of a UAV in the vehicular environment by considering the irregularities of the terrains that might hinder Line-of-Sight (LOS) conditions. The proposed technique takes into account the path loss caused by the terrains. Simulation results show that the optimization algorithm allows us to determine the best position for the deployed UAVs throughout time by considering the movement of the cars, and also accounting for adjustments in terms of flight altitude. In particular, the latter is adjusted by considering the position of the cars on the ground and the profile of surrounding terrains to determine potential communications blockages, while respecting international regulations regarding flight altitude restrictions.
{"title":"optimizing UAV-to-Car Communications in 3D Environments Through Dynamic UAV Positioning","authors":"S. Hadiwardoyo, C. Calafate, Juan-Carlos Cano, K. Krinkin, Dmitry Klionskiy, Enrique Hernández-Orallo, P. Manzoni","doi":"10.1109/DS-RT47707.2019.8958694","DOIUrl":"https://doi.org/10.1109/DS-RT47707.2019.8958694","url":null,"abstract":"Unmanned Aerial Vehicles (UAVs) can act as re-lays in areas with limited infrastructure to support car-to-car communications. Prior studies on UAV-to-car communications showed that the irregularity of the terrains has a significant impact on link quality. Thus, in this paper, we propose a positioning technique that relies on Particle Swarm optimization (PSO) to optimize the positioning of a UAV in the vehicular environment by considering the irregularities of the terrains that might hinder Line-of-Sight (LOS) conditions. The proposed technique takes into account the path loss caused by the terrains. Simulation results show that the optimization algorithm allows us to determine the best position for the deployed UAVs throughout time by considering the movement of the cars, and also accounting for adjustments in terms of flight altitude. In particular, the latter is adjusted by considering the position of the cars on the ground and the profile of surrounding terrains to determine potential communications blockages, while respecting international regulations regarding flight altitude restrictions.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130024873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-01DOI: 10.1109/DS-RT47707.2019.8958653
Malika Bendechache, Sergej Svorobej, Patricia Takako Endo, Manuel Noya Mario, M. Eduardo Ares, James Byrne, Theo Lynn
Simulation can be a powerful technique for evaluating the performance of large-scale cloud computing services in a relatively low cost, low risk and time-sensitive manner. Large-scale data indexing, distribution and management is complex to analyse in a timely manner. In this paper, we extend the CloudSim cloud simulation framework to model and simulate a distributed search engine architecture and its workload characteristics. To test the simulation framework, we develop a model based on a real-world ElasticSearch deployment on Linknovate.com. An experimental evaluation of the framework, comparing simulated and actual query response time, precision and resource utilisation, suggests that the proposed framework is capable of predicting performance at different scales in a precise, accurate and efficient manner. The results can assist ElasticSearch users to manage their scalability and infrastructure requirements.
{"title":"Modelling and Simulation of ElasticSearch using CloudSim","authors":"Malika Bendechache, Sergej Svorobej, Patricia Takako Endo, Manuel Noya Mario, M. Eduardo Ares, James Byrne, Theo Lynn","doi":"10.1109/DS-RT47707.2019.8958653","DOIUrl":"https://doi.org/10.1109/DS-RT47707.2019.8958653","url":null,"abstract":"Simulation can be a powerful technique for evaluating the performance of large-scale cloud computing services in a relatively low cost, low risk and time-sensitive manner. Large-scale data indexing, distribution and management is complex to analyse in a timely manner. In this paper, we extend the CloudSim cloud simulation framework to model and simulate a distributed search engine architecture and its workload characteristics. To test the simulation framework, we develop a model based on a real-world ElasticSearch deployment on Linknovate.com. An experimental evaluation of the framework, comparing simulated and actual query response time, precision and resource utilisation, suggests that the proposed framework is capable of predicting performance at different scales in a precise, accurate and efficient manner. The results can assist ElasticSearch users to manage their scalability and infrastructure requirements.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115403387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-01DOI: 10.1109/DS-RT47707.2019.8958678
P. Tin, N. V. Hien, M. Voznák, L. Sevcik
In this paper, we evaluate and compare performance of multi-hop relaying (MR) protocols under impact of hardware impairments, in terms of outage probability (OP) and throughput (TP). By applying non-orthogonal multiple access (NOMA) technique at each hop, the end-to-end data rate/throughput of the MR protocol can be enhanced, as compared with the conventional one. Particularly, the transmitter at each hop combines two signals, and forwards the combined signal to the receiver which uses successive interference cancelation (SIC) to extract the data. For performance evaluation and comparison, we derive exact closed-form expressions of OP and TP for the considered protocols over Nakagami-m channel. Monte Carlo simulations are then performed to verify the theoretical derivations.
{"title":"Performance Comparison Between NOMA and OMA Relaying Protocols in Multi-Hop Networks over Nakagami-m Fading Channels under Impact of Hardware Impairments","authors":"P. Tin, N. V. Hien, M. Voznák, L. Sevcik","doi":"10.1109/DS-RT47707.2019.8958678","DOIUrl":"https://doi.org/10.1109/DS-RT47707.2019.8958678","url":null,"abstract":"In this paper, we evaluate and compare performance of multi-hop relaying (MR) protocols under impact of hardware impairments, in terms of outage probability (OP) and throughput (TP). By applying non-orthogonal multiple access (NOMA) technique at each hop, the end-to-end data rate/throughput of the MR protocol can be enhanced, as compared with the conventional one. Particularly, the transmitter at each hop combines two signals, and forwards the combined signal to the receiver which uses successive interference cancelation (SIC) to extract the data. For performance evaluation and comparison, we derive exact closed-form expressions of OP and TP for the considered protocols over Nakagami-m channel. Monte Carlo simulations are then performed to verify the theoretical derivations.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"361 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120895730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-01DOI: 10.1109/ds-rt47707.2019.8958673
E. Gelenbe
Over the last decade, the increased automation in the management of computer systems and networks, the rising costs of energy, and the sensitivity about the environmental impact of energy consumption, has resulted in an increase of the importance of energy in the overall running of ICT (Information and Communication) Systems. The deregulation in telecommunication services has also had an impact in this direction because of the increased duplication in telecommunication infrastructures. Furthermore, most cyberattacks, also increase the energy consumption of ICT systems. Thus, today the overall electricity consumed by ICT worldwide is comparable to the total electricity consumption of two major industrial powers: Japan plus Germany. Clearly, of one wishes to save energy in ICT, this may come at the expense of a reduction in the measured Quality of Service (QoS) of ICT systems. Thus we will survey a number of our own research results, covering wireless communications, compute servers and network routing, to offer optimal trade-offs between energy consumption and QoS. The Energy Packet Network (EPN) that we have introduced to optimise the Energy-QoS trade-offs will be described and applied to a number of examples. We will also describe some results on the potential and limitations for communicating and computing with particle spins as a means to achieve energy savings.
{"title":"Energy Consumption and Quality of Service in Computer Systems and Networks","authors":"E. Gelenbe","doi":"10.1109/ds-rt47707.2019.8958673","DOIUrl":"https://doi.org/10.1109/ds-rt47707.2019.8958673","url":null,"abstract":"Over the last decade, the increased automation in the management of computer systems and networks, the rising costs of energy, and the sensitivity about the environmental impact of energy consumption, has resulted in an increase of the importance of energy in the overall running of ICT (Information and Communication) Systems. The deregulation in telecommunication services has also had an impact in this direction because of the increased duplication in telecommunication infrastructures. Furthermore, most cyberattacks, also increase the energy consumption of ICT systems. Thus, today the overall electricity consumed by ICT worldwide is comparable to the total electricity consumption of two major industrial powers: Japan plus Germany. Clearly, of one wishes to save energy in ICT, this may come at the expense of a reduction in the measured Quality of Service (QoS) of ICT systems. Thus we will survey a number of our own research results, covering wireless communications, compute servers and network routing, to offer optimal trade-offs between energy consumption and QoS. The Energy Packet Network (EPN) that we have introduced to optimise the Energy-QoS trade-offs will be described and applied to a number of examples. We will also describe some results on the potential and limitations for communicating and computing with particle spins as a means to achieve energy savings.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"376 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115989348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-01DOI: 10.1109/DS-RT47707.2019.8958701
J. Wubben, Francisco Fabra, C. Calafate, Tomasz Krzeszowski, J. Márquez-Barja, Juan-Carlos Cano, P. Manzoni
Over the last few years, different researchers have been developing protocols and applications in order to land unmanned aerial vehicles (UAVs) autonomously. However, most of the proposed protocols rely on expensive equipment or do not satisfy the high precision needs of some UAV applications, such as package retrieval and delivery. Therefore, in this paper, we present a solution for high precision landing based on the use of ArUco markers. In our solution, a UAV equipped with a camera is able to detect ArUco markers from an altitude of 20 meters. Once the marker is detected, the UAV changes its flight behavior in order to land on the exact position where the marker is located. We evaluated our proposal using our own UAV simulation platform (ArduSim), and validated it using real UAVs. The results show an average offset of only 11 centimeters, which vastly improves the landing accuracy compared to the traditional GPS-based landing, that typically deviates from the intended target by 1 to 3 meters.
{"title":"A vision-based system for autonomous vertical landing of unmanned aerial vehicles","authors":"J. Wubben, Francisco Fabra, C. Calafate, Tomasz Krzeszowski, J. Márquez-Barja, Juan-Carlos Cano, P. Manzoni","doi":"10.1109/DS-RT47707.2019.8958701","DOIUrl":"https://doi.org/10.1109/DS-RT47707.2019.8958701","url":null,"abstract":"Over the last few years, different researchers have been developing protocols and applications in order to land unmanned aerial vehicles (UAVs) autonomously. However, most of the proposed protocols rely on expensive equipment or do not satisfy the high precision needs of some UAV applications, such as package retrieval and delivery. Therefore, in this paper, we present a solution for high precision landing based on the use of ArUco markers. In our solution, a UAV equipped with a camera is able to detect ArUco markers from an altitude of 20 meters. Once the marker is detected, the UAV changes its flight behavior in order to land on the exact position where the marker is located. We evaluated our proposal using our own UAV simulation platform (ArduSim), and validated it using real UAVs. The results show an average offset of only 11 centimeters, which vastly improves the landing accuracy compared to the traditional GPS-based landing, that typically deviates from the intended target by 1 to 3 meters.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121915142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-01DOI: 10.1109/DS-RT47707.2019.8958661
F. Cicirelli, A. Guerrieri, C. Mastroianni, Fabio Palopoli, G. Spezzano, Andrea Vinci
This paper presents a novel approach for the management of buildings by leveraging cognitive technologies. The proposed approach exploits the Deep Reinforcement Learning paradigm to learn from both a physical and a simulated environment so as to optimize people comfort and energy consumption.
{"title":"Comfort-aware Cognitive Buildings Leveraging Deep Reinforcement Learning","authors":"F. Cicirelli, A. Guerrieri, C. Mastroianni, Fabio Palopoli, G. Spezzano, Andrea Vinci","doi":"10.1109/DS-RT47707.2019.8958661","DOIUrl":"https://doi.org/10.1109/DS-RT47707.2019.8958661","url":null,"abstract":"This paper presents a novel approach for the management of buildings by leveraging cognitive technologies. The proposed approach exploits the Deep Reinforcement Learning paradigm to learn from both a physical and a simulated environment so as to optimize people comfort and energy consumption.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127832919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-01DOI: 10.1109/DS-RT47707.2019.8958688
Raouia Masmoudi Ghodhbane, Lucas Lebailly
This paper focuses on the design of a low-latency and low-power OFDM communication system where devices send frames consisting of a reduced number of symbols (one OFDM symbol), with a reduced number of carriers. We study the design of the OFDM receiver blocks in terms of time synchronization and channel estimation. Furthermore, we adapt these OFDM techniques to the case of short frame transmissions in order to meet the requirements of a low-latency and low-power sensor network. Then, we analyse the performance of our solutions and we show that our design allows the system to work close to the theoretical limits. We investigate the impact of the number of pilots on time synchronization performance, and we show the advantage of adding a memory to the channel estimation block.
{"title":"Short Frame OFDM for Sensor Networks: Time Synchronization and Channel Estimation Design","authors":"Raouia Masmoudi Ghodhbane, Lucas Lebailly","doi":"10.1109/DS-RT47707.2019.8958688","DOIUrl":"https://doi.org/10.1109/DS-RT47707.2019.8958688","url":null,"abstract":"This paper focuses on the design of a low-latency and low-power OFDM communication system where devices send frames consisting of a reduced number of symbols (one OFDM symbol), with a reduced number of carriers. We study the design of the OFDM receiver blocks in terms of time synchronization and channel estimation. Furthermore, we adapt these OFDM techniques to the case of short frame transmissions in order to meet the requirements of a low-latency and low-power sensor network. Then, we analyse the performance of our solutions and we show that our design allows the system to work close to the theoretical limits. We investigate the impact of the number of pilots on time synchronization performance, and we show the advantage of adding a memory to the channel estimation block.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129095951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-01DOI: 10.1109/DS-RT47707.2019.8958652
M. Rapelli, C. Casetti, Giandomenico Gagliardi
Traffic simulations are becoming a standard way to study urban mobility patterns, to evaluate new traffic policies and to test modern vehicular technologies. For this reason, in recent years, mobility projects pushed towards an increase in the demand of traffic simulators and towards an extension of their area of investigation, aiming at covering a whole city and its suburbs. In this paper we describe the methodology we followed in the creation of a large-scale traffic simulation of a 400-Km2 area around the Municipality of Turin. Our preliminary results demonstrate that a complete modeling of such a wide tool is possible at the expense of minor simplifications.
{"title":"TuST: from Raw Data to Vehicular Traffic Simulation in Turin","authors":"M. Rapelli, C. Casetti, Giandomenico Gagliardi","doi":"10.1109/DS-RT47707.2019.8958652","DOIUrl":"https://doi.org/10.1109/DS-RT47707.2019.8958652","url":null,"abstract":"Traffic simulations are becoming a standard way to study urban mobility patterns, to evaluate new traffic policies and to test modern vehicular technologies. For this reason, in recent years, mobility projects pushed towards an increase in the demand of traffic simulators and towards an extension of their area of investigation, aiming at covering a whole city and its suburbs. In this paper we describe the methodology we followed in the creation of a large-scale traffic simulation of a 400-Km2 area around the Municipality of Turin. Our preliminary results demonstrate that a complete modeling of such a wide tool is possible at the expense of minor simplifications.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126980661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-05DOI: 10.1109/DS-RT47707.2019.8958669
Andrea Araldo, A. Maria, A. Stefano, G. Morana
Mobility on Demand (MoD) services are revolutionizing the way people move in cities around the world and are often considered a convenient alternative to public transit. MoD is usually intended as a door-to-door service. However, there has been recent interest toward consolidating, e.g., aggregating, the travel demand by limiting the number of admitted stop locations. This implies users have to walk from/to their intended origin/destination.The contribution of this paper is a systematic study the impact of consolidation on the operator cost and on user QoS. We introduce a MoD system where pick-ups and drop-offs can only occur in a limited subset of admitted stop locations. The density of such locations is a system parameter: the less the density, the more the user demand is consolidated. We show that, by decreasing stop density, we can increase system capacity (number of passengers we are able to serve). On the contrary, increasing it, we can improve QoS. The system is tested in AMoDSim, an open-source simulator.This work is a first step toward flexible mobility services that are able to autonomously re-conFigure themselves, favoring capacity or QoS, depending on the amount of travel demand coming from users. In other words, the services we envisage in this work shift their operational mode to any intermediate point in the range from a taxi-like door-to-door service to a bus-like service, with few served stops and more passengers on-board.
{"title":"On the Importance of demand Consolidation in Mobility on Demand","authors":"Andrea Araldo, A. Maria, A. Stefano, G. Morana","doi":"10.1109/DS-RT47707.2019.8958669","DOIUrl":"https://doi.org/10.1109/DS-RT47707.2019.8958669","url":null,"abstract":"Mobility on Demand (MoD) services are revolutionizing the way people move in cities around the world and are often considered a convenient alternative to public transit. MoD is usually intended as a door-to-door service. However, there has been recent interest toward consolidating, e.g., aggregating, the travel demand by limiting the number of admitted stop locations. This implies users have to walk from/to their intended origin/destination.The contribution of this paper is a systematic study the impact of consolidation on the operator cost and on user QoS. We introduce a MoD system where pick-ups and drop-offs can only occur in a limited subset of admitted stop locations. The density of such locations is a system parameter: the less the density, the more the user demand is consolidated. We show that, by decreasing stop density, we can increase system capacity (number of passengers we are able to serve). On the contrary, increasing it, we can improve QoS. The system is tested in AMoDSim, an open-source simulator.This work is a first step toward flexible mobility services that are able to autonomously re-conFigure themselves, favoring capacity or QoS, depending on the amount of travel demand coming from users. In other words, the services we envisage in this work shift their operational mode to any intermediate point in the range from a taxi-like door-to-door service to a bus-like service, with few served stops and more passengers on-board.","PeriodicalId":377914,"journal":{"name":"2019 IEEE/ACM 23rd International Symposium on Distributed Simulation and Real Time Applications (DS-RT)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131260146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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