Bio: Aicha Sahel is an academic researcher from University of Hassan II Casablanca. The author has contributed to research in topics: Routing protocol & Network packet. The author has an hindex of 8, co-authored 50 publications receiving 192 citations.
TL;DR: This paper consecrated their study on Casablanca, the largest city in Morocco, with a realistic mobility model that gives aspects of real vehicular traffic and evaluated the performance of 802.11a (Wi-Fi) and802.11p (DSRC/WAVE) based on three parameters: Packet Delivery Ratio, End-To-End Delay and Throughput.
Abstract: The number of people killed in traffic accidents in Morocco reached 3593 during 2016, compared to 3565 in 2015, registering a slight increase of 0.79%. Thus, the total of traffic accidents over the past year amounted to 81827 against 78864 in 2015, an increase of 3.76%, according to provisional statistics of traffic accidents in 2016. These statistics show that Morocco is one of the countries with the highest mortality rate. In order to decrease these numbers and put an end to this dilemma, we are working on developing vehicle-to-vehicle communication (V2V) in order to provide information and assistance required to avoid collisions, traffic-jam, etc. Vehicular Ad-Hoc Networks (VANETs) have great potential for providing safety and comfort applications for Intelligent Transport Systems (ITS) and to improve traffic safety on roads. In this paper, we have consecrated our study on Casablanca, the largest city in Morocco which has a highway passing through it. Thus, we took two scenarios, first the highway and trunk roads and second the other roads (primary, secondary, tertiary and residential roads). To demonstrate these scenarios, we used various tools such as OpenStreetMap and SUMO to generate a realistic mobility model that gives aspects of real vehicular traffic. Generated scenarios are added to NS-2.35 (Network Simulator) in order to analyze the performance of 802.11a (Wi-Fi) and 802.11p (DSRC/WAVE). We evaluated the performance based on three parameters: Packet Delivery Ratio, End-To-End Delay and Throughput. The results showed that 802.11p is better and more efficient than 802.11a under both scenarios. In addition, 802.11p gives better results in the second scenario than in the first one, and this is due to the number of cars, the authorized speed and the distance between the cars in each scenario.
TL;DR: The experimental results approve that the proposed hybrid algorithm gives an excellent compromise imperceptibility and robustness against several attacks such as Gaussian noise, Saltand-Pepper, Speckle noise, Average filter, Median filter, and Wiener filter compared with existing methods.
Abstract: In the aim to contribute to the security of medical image, we present a robust watermarking method which combines discrete wavelet transform (DWT), discrete cosine transform (DCT) and singular value decomposition (SVD). This approach is intended to insert an invisible image watermark in a medical image. The cover medical image is divided up into the third level of DWT coefficients and then is transformed by DCT and SVD. The same procedure is applied to the watermark image. The singular value of watermark is inserted into the singular value of the high-frequency sub bands of the third level DWT of the cover image. However, the insertion of the watermark in these areas makes it possible to reinforce the robustness of the system of watermarking without hindering the quality of the watermarked image. The performance of the proposed method was evaluated in term of invisibility by calculating the Peak Signal to Noise Ratio (PSNR) between the original and the watermarked image and in term of robustness by measuring the normalized correlation coefficient (NC) between the original watermark and the extracted watermark after applying attacks. The experimental results approve that our proposed hybrid algorithm gives an excellent compromise imperceptibility and robustness against several attacks such as Gaussian noise, Saltand-Pepper, Speckle noise, Average filter, Median filter, and Wiener filter compared with existing methods.
••01 Nov 2017
TL;DR: This paper presents a low-cost directive beam-steering phased array (DBS-PA) antenna using switched line phase shifters, carried out using Agilent AdS and Ansoft HFSS software tools.
Abstract: Beam-steering antennas are the ideal solution for a variety of system applications, it is most commonly achieved through using phased arrays, where phase shifters are used to control the relative of the main-beam. In this paper, a low-cost directive beam-steering phased array (DBS-PA) antenna using switched line phase shifters is demonstrated. The proposed DBS-PA antenna has four micro-strip patch antennas, three power dividers and four phase shifters printed on the same Rogers RT-Durroid substrate with a dielectric constant of 2.2 with dimensions of 8 × 3.5 cm. The phased array antenna has a directivity of 15 dBi and the main beam direction can be switched between the angles of ±30 degrees with a 3dB beam-width of 25 degrees. All design and simulations have been carried out using Agilent AdS and Ansoft HFSS software tools. The frequency considered for the operation is 10 GHz.
••01 May 2017
TL;DR: A robust multiple watermarking which combine discrete wavelet transform (DWT), fast Walsh-Hadamard transform (FWHT) and singular value decomposition (SVD) is presented.
Abstract: The telemedicine is a medical practice which consists in using new technologies of information and communication (NTIC). It makes it possible to facilitate the transfer and diagnosis of several medical data at distance. The security of medical images plays an important role to ensure and guarantee the integrity and confidentiality. This paper presents a robust multiple watermarking which combine discrete wavelet transform (DWT), fast Walsh-Hadamard transform (FWHT) and singular value decomposition (SVD). In our proposed method, we have inserted two watermark images into a single cover medical image. The original medical image is divided until the third level of DWT and then the selected high-frequency sub-bands (HH1 and HH3) are transformed by FWHT and SVD. The same steps are exerted on the first watermark image. Furthermore, the second watermark is divided until the first level and then transformed by SVD. The insertion of the two watermarks is made in the singular values of the original image. The experimental results approve that our contribution gives a better compromise invisibility-capacity-robustness compared with other reported techniques.
TL;DR: A new Hybrid Energy Efficient Static routing protocol (HEESR), combining between clustering and multi-hop routing techniques, which have improved network’s life time, throughput and other compared metrics, in both homogeneous and heterogeneous networks.
Abstract: Wireless sensor networks consist of a large number of nodes deployed randomly in an area of interest. Theses nodes have sensing, computation, and wireless communications capabilities. In another hand nodes have energy constraints since they are equipped by non-rechargeable batteries. To handle this issue, routing protocols consist of designing the network in order to collect and transmit data with less energy consumption. In this paper we presented a new Hybrid Energy Efficient Static routing protocol (HEESR), combining between clustering and multi-hop routing techniques. HEESR is dividing the network into several levels. For each round, it creates clusters, route the collected data through gateways called Independent Nodes, elected using a new dynamic approach and introduces Dormant nodes. Finally, the proposed HEESR have improved network’s life time, throughput and other compared metrics, in both homogeneous and heterogeneous networks, and prolonged network’s stability zone up to 98.4% compared to LEACH, 98% compared to DEEC and up to 40.5% compared to SMR.
01 Jan 2011
TL;DR: In this paper, a US frontier residential aggregate energy demand function using panel data for 48 US states over the period 1995 to 2007 using stochastic frontier analysis (SFA) is estimated.
Abstract: This paper estimates a US frontier residential aggregate energy demand function using panel data for 48 ‘states’ over the period 1995 to 2007 using stochastic frontier analysis (SFA). Utilizing an econometric energy demand model, the (in)efficiency of each state is modeled and it is argued that this represents a measure of the inefficient use of residential energy in each state (i.e. ‘waste energy’). This underlying efficiency for the US is therefore observed for each state as well as the relative efficiency across the states. Moreover, the analysis suggests that energy intensity is not necessarily a good indicator of energy efficiency, whereas by controlling for a range of economic and other factors, the measure of energy efficiency obtained via this approach is. This is a novel approach to model residential energy demand and efficiency and it is arguably particularly relevant given current US energy policy discussions related to energy efficiency.
TL;DR: Comparisons between indoor localization systems in terms of accuracy, cost, advantages, and disadvantages are summarized and different detection techniques are presented.
Abstract: This paper introduces a review article on indoor localization techniques and technologies. The paper starts with current localization systems and summarizes comparisons between these systems in terms of accuracy, cost, advantages, and disadvantages. Also, the paper presents different detection techniques and compare them in terms of accuracy and cost. Finally, localization methods and algorithms, including angle of arrival (AOA), time of arrival (TOA), and recived signal strength (RSS) are introduced. The study contains concepts, requirements, and specifications for each category of methods presents pros and cons for investigated methods, and conducts comparisons between them.
TL;DR: An extensive overview of the ITS and the evolution of ITS to VANets is provided, the details of VANETs are provided, and the privacy and security attacks in VANets with their applications and challenges are discussed.
Abstract: Over the past few decades, the intelligent transportation system (ITS) have emerged with new technologies and becomes the data-driven ITS, because the substantial amount of data is assembled from the multiple sources. Vehicular Ad hoc networks (VANETs), are a particular case of ad hoc networks that are used in the smart ITS. VANETs have become one of the most, encouraging, promising, and fastest-growing subsets of the mobile ad hoc networks (MANETs). They are comprised of smart vehicles and roadside units (RSUs) and on-board units (OBUs) which communicate through unreliable wireless media. Other than lacking infrastructure, delivering entities move with different increasing speeds. Thus, this delays establishing reliable end-to-end communication paths and having efficient data transfer. In this manner, VANETs have diverse system concerns and security difficulties in getting the accessibility of ubiquitous availability, secure communication, interchanges, and reputation management system. Which influence the trust in collaboration and arrangement between the portable system. By their fluctuation in nature, they are genuinely defenseless against assaults, which may result in life-jeopardizing circumstances. In this survey, we provide an extensive overview of the ITS and the evolution of ITS to VANETs. We provide the details of VANETs, discussed the privacy and security attacks in VANETs with their applications and challenges. We address the effectiveness of VANETs and cloud computing with architecture and related privacy and security issues. We also examined the communication protocols for each network layer with the relevant attacks occurred at each layer. We also discussed the potential benefits of the different proposed techniques related to VANETs, application, and challenges in details. In the end, we provide a conclusion with some open and emerging issues in VANETs.
TL;DR: This paper presents an overview of IEEE 802.11p, with a particular focus on its adoption in an ITS setting, and analyzes both MAC and PHY layers in a dedicated short-range communication (DSRC) environment.
Abstract: Road safety is an active area of research for the automotive industry, and certainly one of ongoing interest to governments around the world. The intelligent transportation system (ITS) is one of several viable solutions with which to improve road safety, where the communication medium (e.g., among vehicles and between vehicles and the other components in an ITS environment, such as roadside infrastructure) is typically wireless. A typical communication standard adopted by car manufacturers is IEEE 802.11p for communications. Thus, this paper presents an overview of IEEE 802.11p, with a particular focus on its adoption in an ITS setting. Specifically, we analyze both MAC and PHY layers in a dedicated short-range communication (DSRC) environment.
TL;DR: In this article, the authors present a comprehensive study of AV technologies and identify the main advantages, disadvantages, and challenges of AV communication technologies based on three main categories: long range, medium range, and short range.
Abstract: The Department of Transport in the United Kingdom recorded 25,080 motor vehicle fatalities in 2019. This situation stresses the need for an intelligent transport system (ITS) that improves road safety and security by avoiding human errors with the use of autonomous vehicles (AVs). Therefore, this survey discusses the current development of two main components of an ITS: (1) gathering of AVs surrounding data using sensors; and (2) enabling vehicular communication technologies. First, the paper discusses various sensors and their role in AVs. Then, various communication technologies for AVs to facilitate vehicle to everything (V2X) communication are discussed. Based on the transmission range, these technologies are grouped into three main categories: long-range, medium-range and short-range. The short-range group presents the development of Bluetooth, ZigBee and ultra-wide band communication for AVs. The medium-range examines the properties of dedicated short-range communications (DSRC). Finally, the long-range group presents the cellular-vehicle to everything (C-V2X) and 5G-new radio (5G-NR). An important characteristic which differentiates each category and its suitable application is latency. This research presents a comprehensive study of AV technologies and identifies the main advantages, disadvantages, and challenges.