Alia Ghaddar - Academia.edu (original) (raw)

Papers by Alia Ghaddar

Wireless sensor networks are of energy-constrained nature, which calls for energy efficient proto... more Wireless sensor networks are of energy-constrained nature, which calls for energy efficient protocols as a primary design goal. Thus, minimizing energy consumption is a main challenge. We are concerned in how collected data by sensors, can be processed to increase the relevance of certain mass of data and reduce the overall data traffic. Since sensor nodes are often densely de-ployed, the data collected by nearby nodes are either redundant or correlated. One of the great challenges for the aforementioned problem is to exploit temporal and spatial correlation among the source nodes. Our work is composed of two main tasks: 1- A predictive modeling task that aims to capture the temporal corre-lation among collected data. 2- A data similarity detection task that measures the data similarity based on the spatial correlation.

Ad Hoc Sens. Wirel. Networks, 2012

Wireless sensor networks are of energy-constrained nature, which calls for energy efficient proto... more Wireless sensor networks are of energy-constrained nature, which calls for energy efficient protocols as a primary design goal. Thus, minimizing energy consumption is a main challenge.We are concerned in howcollected data by sensors, can be processed to increase the relevance of certain mass of data and reduce the overall data traffic. Since sensor nodes are often densely deployed, the data collected by nearby nodes are either redundant or correlated. One of the great challenges for the aforementioned problem is to exploit temporal and spatial correlation among the source nodes. Our work is composed of two main tasks: 1- A predictive modeling task that aims to capture the temporal correlation among collected data. 2- A data similarity detection task that measures the data similarity based on the spatial correlation.

2019 IEEE/ACS 16th International Conference on Computer Systems and Applications (AICCSA), 2019

Two of the main challenges in wireless sensor networks (WSNs) are connectivity and coverage. Conn... more Two of the main challenges in wireless sensor networks (WSNs) are connectivity and coverage. Connectivity keeps different nodes in the network linked and to exchange data. Coverage affects the efficiency of the operating sensors used in the network. This paper proposes a novel resilient incremental algorithm that improves the coverage of randomly distributed mobile devices within a heterogeneous or homogeneous environment. This algorithm guarantees connectivity by ensuring at least 2-connected neighbors for any device in the network. Results showed up to 89% coverage improvement in a heterogeneous environment and up to 99% coverage improvement in a homogeneous environment.

2019 International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 2019

The performance of WSNs relies on the quality of the collected data. One of the main challenges i... more The performance of WSNs relies on the quality of the collected data. One of the main challenges is how to efficiently deliver the sensed measurements to the destination with a maximum fidelity to the probed data. Data measured by sensors require an efficient ranking measure to differentiate between normal and anomalous values. In this paper, we propose a local anomaly detector algorithm that uses Half-space trees to train and test data instances. It is based on mass ranking with difference in the way we score data and isolate anomalies. Experimental results show that our algorithm has better performance with high accuracy, low time and space complexity comparing to Local Outlier Factor and Mass estimation.

Sensors

Area monitoring and surveillance are some of the main applications for Unmanned Aerial Vehicle (U... more Area monitoring and surveillance are some of the main applications for Unmanned Aerial Vehicle (UAV) networks. The scientific problem that arises from this application concerns the way the area must be covered to fulfill the mission requirements. One of the main challenges is to determine the paths for the UAVs that optimize the usage of resources while minimizing the mission time. Different approaches rely on area partitioning strategies. Depending on the size and complexity of the area to monitor, it is possible to decompose it exactly or approximately. This paper proposes a partitioning method called Parallel Partitioning along a Side (PPS). In the proposed method, grid-mapping and grid-subdivision of the area, as well as area partitioning are performed to plan the UAVs path. An extra challenge, also tackled in this work, is the presence of non-flying zones (NFZs). These zones are areas that UAVs must not cover or pass over it. The proposal is extensively evaluated, in comparison...

IOP Conference Series: Materials Science and Engineering

Future Internet

The internet of Things (IoT) has attracted significant attention in many applications in both aca... more The internet of Things (IoT) has attracted significant attention in many applications in both academic and industrial areas. In IoT, each object can have the capabilities of sensing, identifying, networking and processing to communicate with ubiquitous objects and services. Often this paradigm (IoT) using Wireless Sensor Networks must cover large area of interest (AoI) with huge number of devices. As these devices might be battery powered and randomly deployed, their long-term availability and connectivity for area coverage is very important, in particular in harsh environments. Moreover, a poor distribution of devices may lead to coverage holes and degradation to the quality of service. In this paper, we propose an approach for self-organization and coverage maximization. We present a distributed algorithm for “Maintaining Connectivity and Coverage Maximization” called M C C M . The algorithm operates on different movable devices in homogeneous and heterogeneous distribution. It do...

Future Internet

The presence of obstacles like a tree, buildings, or birds along the path of a drone has the abil... more The presence of obstacles like a tree, buildings, or birds along the path of a drone has the ability to endanger and harm the UAV’s flight mission. Avoiding obstacles is one of the critical challenging keys to successfully achieve a UAV’s mission. The path planning needs to be adapted to make intelligent and accurate avoidance online and in time. In this paper, we propose an energy-aware grid based solution for obstacle avoidance (EAOA). Our work is based on two phases: in the first one, a trajectory path is generated offline using the area top-view. The second phase depends on the path obtained in the first phase. A camera captures a frontal view of the scene that contains the obstacle, then the algorithm determines the new position where the drone has to move to, in order to bypass the obstacle. In this paper, the obstacles are static. The results show a gain in energy and completion time using 3D scene information compared to 2D scene information.

Modern technology provides great access to information. With the development of communications te... more Modern technology provides great access to information. With the development of communications technologies, the nature of information changed from retrieving simple documents to accessing visual-based social media, digital platforms, video-streaming, and music. In that process, search engines and social media platforms like Google, Facebook, Twitter and so on, are used to locate information and to connect with other people, and businesses. It is a platform to learn more about people we associate with and expose aspects of our lives that were previously hidden such as dates, family gatherings, nights out and so on. It is also affecting our relationships with friends and family members. This study aims to investigate the effect of social media and technological tools on the relationship between couples and among family members in Lebanon. We examine whether people are becoming more interested in technology than in people around them and consequently are losing real-life connection. The study is based on the time spent on social media, its effect on the relationship, and how much it contributes to marital problems, emotional disrespect, cheating, breakup, divorce, and others.

Multimedia Tools and Applications

Multi-view video systems are designed to allow users to watch 3D videos or a scene recorded by mu... more Multi-view video systems are designed to allow users to watch 3D videos or a scene recorded by multiple cameras from multiple viewpoints. They are actually used by crowd sourced journalism services or to cover events using a set of wireless drones/sensors filming the same scene, etc. Multi-view videos are captured by multiple cameras at different positions with significant correlations between neighboring views. Owing to the increased data volume of multi-view video, highly efficient encoding techniques are needed. The common idea for Multi-View Video Coding (MVC) is to further exploit the redundancy between adjacent views. In this paper, we focus on the acquisition phase of the multi-view video system. We propose a Mobile Multi-view Video Streaming scheme with Constant Order Encoding (MMVS/COE). It encodes by exploiting the inter/intra-view dependency to reduce redundancy and optimize the tradeoff between traffic volume (bite rate) and video quality. Evaluations’ results show that MMVS/COE reduces traffic, compared to existing methods, mainly MVC/MC, by decreasing redundancies among video streams while maintaining video quality.

IJARCCE

WSNs are composed of limited-power sensors. Replacing or recharging sensors, especially when depl... more WSNs are composed of limited-power sensors. Replacing or recharging sensors, especially when deployed in places where human intervention is risky, is an important challenge. Therefore, and since communication is the major energy consuming operation [1], ensuring an energy efficient usage is a major concern. Clustering is one of the techniques used for this purpose [2]. It decreases the number of sensors which take part in transmission thereby assist in power consumption [3]. The sensors are organized into clusters. Each Cluster has a Cluster Head (CH) to which only other cluster members send data. CHs gather information and send it to a base station for processing. We propose an method for CH selection based on multiple criteria (distance to base station, distance to cluster members, energy cost and number of rounds) using fuzzy logic. Simulation results show that MUCH decreases the energy consumption comparing to LEACH thus increases the network lifetime.

International Journal of Ad hoc, Sensor & Ubiquitous Computing, 2013

In a wide range of applications, large amounts of floating-point data are generated by Wireless S... more In a wide range of applications, large amounts of floating-point data are generated by Wireless Sensor Networks (WSNs). This data is often transferred between several sensor nodes, in a multi-hop fashion, before reaching its ultimate destination (the base station). It is well known that data communications is the most energy-consuming task in sensor nodes [1]. This can be a great concern when the nodes are constrained in energy. Therefore, the amount of data to be transferred between nodes should be reduced to save energy. In this paper, we investigate data compression for resource-constraint WSNs; we introduce MAS as a novel adaptive lossless floating-point data compression algorithm for WSNs. MAS exploits the disproportionality in energy consumption between data transmission and processing. Simulation results, obtained from OMNeT++ and Atmel Studio, show that MAS surpasses other tested compression algorithms in terms of compression ratio, compression speed, memory requirements and most importantly energy savings.

… Conference on Mobile …, 2010

Abstract—A primary purpose of sensing in a sensor network is to collect and aggregate information... more Abstract—A primary purpose of sensing in a sensor network is to collect and aggregate information about a phenomenon of interest. The batteries on today's wireless sensor barely last a few days, and nodes typically expend a lot of energy in computation and wireless ...

World of Wireless …, 2010

Abstract—Extending the lifetime of wireless sensor networks remains the most challenging and dema... more Abstract—Extending the lifetime of wireless sensor networks remains the most challenging and demand-ing requirement that impedes large-scale deploy-ments. The basic operation in WSNs is the systematic gathering and transmission of sensed data to a base station for further ...

… (WCNC), 2011 IEEE, 2011

Résumé : Knowledge discovery and data analysis in resource constrained wireless sensor networks f... more Résumé : Knowledge discovery and data analysis in resource constrained wireless sensor networks faces different challenges. One of the main challenges is to identify misbehaviors or anomalies with high accuracy while minimizing energy consumption in the network. In this paper, we ...

Wireless sensor networks are of energy-constrained nature, which calls for energy efficient proto... more Wireless sensor networks are of energy-constrained nature, which calls for energy efficient protocols as a primary design goal. Thus, minimizing energy consumption is a main challenge. We are concerned in how collected data by sensors, can be processed to increase the relevance of certain mass of data and reduce the overall data traffic. Since sensor nodes are often densely de-ployed, the data collected by nearby nodes are either redundant or correlated. One of the great challenges for the aforementioned problem is to exploit temporal and spatial correlation among the source nodes. Our work is composed of two main tasks: 1- A predictive modeling task that aims to capture the temporal corre-lation among collected data. 2- A data similarity detection task that measures the data similarity based on the spatial correlation.

Ad Hoc Sens. Wirel. Networks, 2012

Wireless sensor networks are of energy-constrained nature, which calls for energy efficient proto... more Wireless sensor networks are of energy-constrained nature, which calls for energy efficient protocols as a primary design goal. Thus, minimizing energy consumption is a main challenge.We are concerned in howcollected data by sensors, can be processed to increase the relevance of certain mass of data and reduce the overall data traffic. Since sensor nodes are often densely deployed, the data collected by nearby nodes are either redundant or correlated. One of the great challenges for the aforementioned problem is to exploit temporal and spatial correlation among the source nodes. Our work is composed of two main tasks: 1- A predictive modeling task that aims to capture the temporal correlation among collected data. 2- A data similarity detection task that measures the data similarity based on the spatial correlation.

2019 IEEE/ACS 16th International Conference on Computer Systems and Applications (AICCSA), 2019

Two of the main challenges in wireless sensor networks (WSNs) are connectivity and coverage. Conn... more Two of the main challenges in wireless sensor networks (WSNs) are connectivity and coverage. Connectivity keeps different nodes in the network linked and to exchange data. Coverage affects the efficiency of the operating sensors used in the network. This paper proposes a novel resilient incremental algorithm that improves the coverage of randomly distributed mobile devices within a heterogeneous or homogeneous environment. This algorithm guarantees connectivity by ensuring at least 2-connected neighbors for any device in the network. Results showed up to 89% coverage improvement in a heterogeneous environment and up to 99% coverage improvement in a homogeneous environment.

2019 International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 2019

The performance of WSNs relies on the quality of the collected data. One of the main challenges i... more The performance of WSNs relies on the quality of the collected data. One of the main challenges is how to efficiently deliver the sensed measurements to the destination with a maximum fidelity to the probed data. Data measured by sensors require an efficient ranking measure to differentiate between normal and anomalous values. In this paper, we propose a local anomaly detector algorithm that uses Half-space trees to train and test data instances. It is based on mass ranking with difference in the way we score data and isolate anomalies. Experimental results show that our algorithm has better performance with high accuracy, low time and space complexity comparing to Local Outlier Factor and Mass estimation.

Sensors

Area monitoring and surveillance are some of the main applications for Unmanned Aerial Vehicle (U... more Area monitoring and surveillance are some of the main applications for Unmanned Aerial Vehicle (UAV) networks. The scientific problem that arises from this application concerns the way the area must be covered to fulfill the mission requirements. One of the main challenges is to determine the paths for the UAVs that optimize the usage of resources while minimizing the mission time. Different approaches rely on area partitioning strategies. Depending on the size and complexity of the area to monitor, it is possible to decompose it exactly or approximately. This paper proposes a partitioning method called Parallel Partitioning along a Side (PPS). In the proposed method, grid-mapping and grid-subdivision of the area, as well as area partitioning are performed to plan the UAVs path. An extra challenge, also tackled in this work, is the presence of non-flying zones (NFZs). These zones are areas that UAVs must not cover or pass over it. The proposal is extensively evaluated, in comparison...

IOP Conference Series: Materials Science and Engineering

Future Internet

The internet of Things (IoT) has attracted significant attention in many applications in both aca... more The internet of Things (IoT) has attracted significant attention in many applications in both academic and industrial areas. In IoT, each object can have the capabilities of sensing, identifying, networking and processing to communicate with ubiquitous objects and services. Often this paradigm (IoT) using Wireless Sensor Networks must cover large area of interest (AoI) with huge number of devices. As these devices might be battery powered and randomly deployed, their long-term availability and connectivity for area coverage is very important, in particular in harsh environments. Moreover, a poor distribution of devices may lead to coverage holes and degradation to the quality of service. In this paper, we propose an approach for self-organization and coverage maximization. We present a distributed algorithm for “Maintaining Connectivity and Coverage Maximization” called M C C M . The algorithm operates on different movable devices in homogeneous and heterogeneous distribution. It do...

Future Internet

The presence of obstacles like a tree, buildings, or birds along the path of a drone has the abil... more The presence of obstacles like a tree, buildings, or birds along the path of a drone has the ability to endanger and harm the UAV’s flight mission. Avoiding obstacles is one of the critical challenging keys to successfully achieve a UAV’s mission. The path planning needs to be adapted to make intelligent and accurate avoidance online and in time. In this paper, we propose an energy-aware grid based solution for obstacle avoidance (EAOA). Our work is based on two phases: in the first one, a trajectory path is generated offline using the area top-view. The second phase depends on the path obtained in the first phase. A camera captures a frontal view of the scene that contains the obstacle, then the algorithm determines the new position where the drone has to move to, in order to bypass the obstacle. In this paper, the obstacles are static. The results show a gain in energy and completion time using 3D scene information compared to 2D scene information.

Modern technology provides great access to information. With the development of communications te... more Modern technology provides great access to information. With the development of communications technologies, the nature of information changed from retrieving simple documents to accessing visual-based social media, digital platforms, video-streaming, and music. In that process, search engines and social media platforms like Google, Facebook, Twitter and so on, are used to locate information and to connect with other people, and businesses. It is a platform to learn more about people we associate with and expose aspects of our lives that were previously hidden such as dates, family gatherings, nights out and so on. It is also affecting our relationships with friends and family members. This study aims to investigate the effect of social media and technological tools on the relationship between couples and among family members in Lebanon. We examine whether people are becoming more interested in technology than in people around them and consequently are losing real-life connection. The study is based on the time spent on social media, its effect on the relationship, and how much it contributes to marital problems, emotional disrespect, cheating, breakup, divorce, and others.

Multimedia Tools and Applications

Multi-view video systems are designed to allow users to watch 3D videos or a scene recorded by mu... more Multi-view video systems are designed to allow users to watch 3D videos or a scene recorded by multiple cameras from multiple viewpoints. They are actually used by crowd sourced journalism services or to cover events using a set of wireless drones/sensors filming the same scene, etc. Multi-view videos are captured by multiple cameras at different positions with significant correlations between neighboring views. Owing to the increased data volume of multi-view video, highly efficient encoding techniques are needed. The common idea for Multi-View Video Coding (MVC) is to further exploit the redundancy between adjacent views. In this paper, we focus on the acquisition phase of the multi-view video system. We propose a Mobile Multi-view Video Streaming scheme with Constant Order Encoding (MMVS/COE). It encodes by exploiting the inter/intra-view dependency to reduce redundancy and optimize the tradeoff between traffic volume (bite rate) and video quality. Evaluations’ results show that MMVS/COE reduces traffic, compared to existing methods, mainly MVC/MC, by decreasing redundancies among video streams while maintaining video quality.

IJARCCE

WSNs are composed of limited-power sensors. Replacing or recharging sensors, especially when depl... more WSNs are composed of limited-power sensors. Replacing or recharging sensors, especially when deployed in places where human intervention is risky, is an important challenge. Therefore, and since communication is the major energy consuming operation [1], ensuring an energy efficient usage is a major concern. Clustering is one of the techniques used for this purpose [2]. It decreases the number of sensors which take part in transmission thereby assist in power consumption [3]. The sensors are organized into clusters. Each Cluster has a Cluster Head (CH) to which only other cluster members send data. CHs gather information and send it to a base station for processing. We propose an method for CH selection based on multiple criteria (distance to base station, distance to cluster members, energy cost and number of rounds) using fuzzy logic. Simulation results show that MUCH decreases the energy consumption comparing to LEACH thus increases the network lifetime.

International Journal of Ad hoc, Sensor & Ubiquitous Computing, 2013

In a wide range of applications, large amounts of floating-point data are generated by Wireless S... more In a wide range of applications, large amounts of floating-point data are generated by Wireless Sensor Networks (WSNs). This data is often transferred between several sensor nodes, in a multi-hop fashion, before reaching its ultimate destination (the base station). It is well known that data communications is the most energy-consuming task in sensor nodes [1]. This can be a great concern when the nodes are constrained in energy. Therefore, the amount of data to be transferred between nodes should be reduced to save energy. In this paper, we investigate data compression for resource-constraint WSNs; we introduce MAS as a novel adaptive lossless floating-point data compression algorithm for WSNs. MAS exploits the disproportionality in energy consumption between data transmission and processing. Simulation results, obtained from OMNeT++ and Atmel Studio, show that MAS surpasses other tested compression algorithms in terms of compression ratio, compression speed, memory requirements and most importantly energy savings.

… Conference on Mobile …, 2010

Abstract—A primary purpose of sensing in a sensor network is to collect and aggregate information... more Abstract—A primary purpose of sensing in a sensor network is to collect and aggregate information about a phenomenon of interest. The batteries on today's wireless sensor barely last a few days, and nodes typically expend a lot of energy in computation and wireless ...

World of Wireless …, 2010

Abstract—Extending the lifetime of wireless sensor networks remains the most challenging and dema... more Abstract—Extending the lifetime of wireless sensor networks remains the most challenging and demand-ing requirement that impedes large-scale deploy-ments. The basic operation in WSNs is the systematic gathering and transmission of sensed data to a base station for further ...

… (WCNC), 2011 IEEE, 2011

Résumé : Knowledge discovery and data analysis in resource constrained wireless sensor networks f... more Résumé : Knowledge discovery and data analysis in resource constrained wireless sensor networks faces different challenges. One of the main challenges is to identify misbehaviors or anomalies with high accuracy while minimizing energy consumption in the network. In this paper, we ...