A F M SHAHEN SHAH (original) (raw)

Papers by A F M SHAHEN SHAH

Performance Comparison of PEGASIS, HEED and LEACH Protocols in Wireless Sensor Networks

DergiPark (Istanbul University), Aug 23, 2022

İşbirlikli insansız hava araçlarının iletişiminin Nakagami-m sönümlemeli kanal altında etkisi

Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi

Bu çalışmada, insansız hava araçları (unmanned aerial vehicles, UAV) için işbirlikli iletim ortam... more Bu çalışmada, insansız hava araçları (unmanned aerial vehicles, UAV) için işbirlikli iletim ortam erişim kontrolü (cooperative transmission medium access conrol, CT-MAC) protokolünün Nakagami-m kanal sönümlemesi üzerine performansı araştırılmıştır. Önerilen protokol, verimi artırmak için esas olarak doğrudan iletim (DT) ve işbirlikli iletim (CT) modlarını içermektedir. Ayrıca, uygun bir veri iletim modunu seçmek ve optimal röleyi seçmek için algoritma tanımlanmaktadır. Yalnızca doğrudan iletişim için özel olarak tasarlanmış IEEE 802.11 standartlarında tanımlanan mekanizma, işbirlikli iletişim için uygun değildir. Bu nedenle, yeni kontrol paketleri kullanılır ve mevcut kontrol paketi formatı, işbirliğine dayalı iletişimi desteklemek üzere değiştirilmiştir. Önerilen CT-MAC protokolünün performans analizini gerçekleştirmek için, doymamış Markov Zinciri modeline dayanan bir analitik model simülasyonla türetilip ve doğrulanmıştır. Benzetim sonuçları, önerilen protokolün sistem verimini e...

Inspecting Vanet from Various Critical Angles – a Systematic Review

SSRN Electronic Journal

TURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES, 2021

The automated Interstitial Lung Diseases (ILDs) classification technique is essential for assisti... more The automated Interstitial Lung Diseases (ILDs) classification technique is essential for assisting clinicians during the diagnosis process. Detecting and classifying ILDs patterns is a challenging problem. This paper introduces an end-to-end deep convolution neural network (CNN) for classifying ILDs patterns. The proposed model comprises four convolutional layers with different kernel sizes and Rectified Linear Unit (ReLU) activation function, followed by batch normalization and max-pooling with a size equal to the final feature map size well as four dense layers. We used the ADAM optimizer to minimize categorical cross-entropy. A dataset consisting of 21328 image patches of 128 CT scans with five classes is taken to train and assess the proposed model. A comparison study showed that the presented model outperformed pre-trained CNNs and five-fold cross-validation on the same dataset. For ILDs pattern classification, the proposed approach achieved the accuracy scores of 99.09% and the average F score of 97.9% that outperforms three pre-trained CNNs. These outcomes show that the proposed model is relatively state-of-the-art in precision, recall, f score, and accuracy.

Sensors, 2021

The efficiency of cooperative communication protocols to increase the reliability and range of tr... more The efficiency of cooperative communication protocols to increase the reliability and range of transmission for Vehicular Ad hoc Network (VANET) is proven, but identity verification and communication security are required to be ensured. Though it is difficult to maintain strong network connections between vehicles because of there high mobility, with the help of cooperative communication, it is possible to increase the communication efficiency, minimise delay, packet loss, and Packet Dropping Rate (PDR). However, cooperating with unknown or unauthorized vehicles could result in information theft, privacy leakage, vulnerable to different security attacks, etc. In this paper, a blockchain based secure and privacy preserving authentication protocol is proposed for the Internet of Vehicles (IoV). Blockchain is utilized to store and manage the authentication information in a distributed and decentralized environment and developed on the Ethereum platform that uses a digital signature alg...

The Performance of the IEEE 802.11 DCF for Different Contention Window in VANETs

2018 41st International Conference on Telecommunications and Signal Processing (TSP), 2018

In this paper, an analytical model is developed to investigate the performance of the IEEE 802.11... more In this paper, an analytical model is developed to investigate the performance of the IEEE 802.11 Distributed Coordination Function (DCF) for different contention window in vehicular ad hoc networks (VANETs). The relationship between performance metrics and contention window size is derived by analytical analysis based on two-dimensional (2D) Markov chain model. The channel busy probability, successful transmission probability, collision probability, throughput and packet dropping rate (PDR) are obtained. The simulation result is also demonstrated to understand the performance of IEEE 802.11 DCF in VANETs for different contention window.

Performance and Complexity Analysis of MAC Protocol for VANETs

2019 IEEE 10th Annual Information Technology, Electronics and Mobile Communication Conference (IEMCON), 2019

The IEEE 802.11 outlined the MAC layer specification for vehicular ad hoc networks (VANETs). In t... more The IEEE 802.11 outlined the MAC layer specification for vehicular ad hoc networks (VANETs). In this paper, to assess the performance of the IEEE 802.11 medium access control (MAC) for VANETs, an analytical model based on Markov chain model is presented. The parameters that could impact performance such as number of vehicles, velocity, vehicle density, contention window (CW) size, packet size, transmission range etc. are considered. The relationship among parameters and performance metrics are derived. The probability of successful transmission, throughput, and delay expressions are obtained. Complexity analysis is presented. Furthermore, to verify the analytical studies numerical results are demonstrated and whether the IEEE 802.11 can fulfill the performance criteria for VANETs or not is checked.

Advances in Intelligent Systems and Computing, 2018

In vehicular ad hoc networks (VANETs), high relative node mobility can result in rapid topology c... more In vehicular ad hoc networks (VANETs), high relative node mobility can result in rapid topology changes with frequent link breakage and unstable communications which causes collision and packet loss. Alternatively, cluster based communication can improve the reliability of communication. In this paper, a QoS aware cluster-based MAC (qCB-MAC) protocol for VANETs is proposed. The cluster formation mechanism is defined. New control packets are introduced and existing control packets are modified to support cluster based communications. Channel access mechanism is based on the IEEE 802.11 EDCA mechanism for different access categories (ACs) to ensure desired QoS at the MAC layer. Markov chain model based analytical analysis is presented to explore the performance of the proposed MAC protocol. Moreover, numerical results are presented to verify the performance of the proposed qCB-MAC protocol for different ACs. The proposed qCB-MAC protocol improves the system throughput and ensures desired QoS.

Computers, Materials & Continua, 2021

Vehicular Ad hoc Networks (VANETs) become a very crucial addition in the Intelligent Transportati... more Vehicular Ad hoc Networks (VANETs) become a very crucial addition in the Intelligent Transportation System (ITS). It is challenging for a VANET system to provide security services and parallelly maintain high throughput by utilizing limited resources. To overcome these challenges, we propose a blockchain-based Secured Cluster-based MAC (SCB-MAC) protocol. The nearby vehicles heading towards the same direction will form a cluster and each of the clusters has its blockchain to store and distribute the safety messages. The message which contains emergency information and requires Strict Delay Requirement (SDR) for transmission are called safety messages (SM). Cluster Members (CMs) sign SMs with their private keys while sending them to the blockchain to confirm authentication, integrity, and confidentiality of the message. A Certificate Authority (CA) is responsible for physical verification, key generation, and privacy preservation of the vehicles. We implemented a test scenario as proof of concept and tested the safety message transmission (SMT) protocol in a real-world platform. Computational and storage overhead analysis shows that the proposed protocol for SMT implements security, authentication, integrity, robustness, non-repudiation, etc. while maintaining the SDR. Messages that are less important compared to the SMs are called non-safety messages (NSM) and vehicles use RTS/CTS mechanism for NSM transmission. Numerical studies show that the proposed NSM transmission method maintains 6 times more throughput, 2 times less delay and 125% less Packet Dropping Rate (PDR) than traditional MAC protocols. These results prove that the proposed protocol outperforms the traditional MAC protocols.

Deep Convolutional Neural Networks-Based Sign Language Recognition System

2021 IEEE 12th Annual Information Technology, Electronics and Mobile Communication Conference (IEMCON), 2021

Deaf individuals rely heavily on sign languages. They make use of them to communicate with others... more Deaf individuals rely heavily on sign languages. They make use of them to communicate with others. Although deaf individuals are familiar with sign language, but it is not widely understood by the general public. In this article, sign language recognition through convolutional neural network (CNN) system is developed for those who aren't familiar with sign language. American sign language letters are utilized in this work. We tried to create a translator for these letters for people who do not know sign language, and we used GoogleNet, a CNN, using the transfer learning method. Our dataset was used to train the network. The network model and network weights are recorded for the test data set once network training is finished. The accuracy of this sign language recognition system is 91.02%.

2017 10th International Conference on Electrical and Electronics Engineering (ELECO), 2017

In this paper, Adaptive Model Predictive Control (AMPC) based Energy Management Strategy (EMS) fo... more In this paper, Adaptive Model Predictive Control (AMPC) based Energy Management Strategy (EMS) for Hybrid Electric Vehicles (HEVs) is proposed to minimize the hydrogen consumption and to increase the energy sources lifetime. The EMS problem is simplified according to the control structure of the vehicle. Moreover, adaptive algorithm is used to dynamically adjust the weights of targets. The Energetic Macroscopic Representation(EMR) and control scheme of the vehicle is implemented in MATLAB-Simulink™. To test the performance two standard driving cycles and a real urban cycle are used. The simulation results of proposed AMPC show a noticeable improvement in fuel economy and battery charge-sustainability.

Designing and Analysis of IEEE 802.11 MAC for UAVs Ad Hoc Networks

2019 IEEE 10th Annual Ubiquitous Computing, Electronics & Mobile Communication Conference (UEMCON), 2019

Unmanned aerial vehicles (UAVs) are popular because they are low cost and do not put in danger hu... more Unmanned aerial vehicles (UAVs) are popular because they are low cost and do not put in danger human pilot lives. In this study, performance of IEEE 802.11 medium access control (MAC) for UAVs ad hoc networks is studied using an analytical model based on Markov chain model. Three dimensional (3D) nature and high mobility are main characteristics of UAVs ad hoc networks which are considered. The relationship among parameters and performance metrics such as throughput, packet dropping rate (PDR), and delay expressions are derived. Complexity analysis and numerical results are presented. Moreover, to ensure safe and efficient communication in UAVs ad hoc networks, IEEE 802.11 MAC can satisfy the performance requirements or not is investigated.

Performance Optimization by Using Artificial Neural Network Algorithms in VANETs

2019 42nd International Conference on Telecommunications and Signal Processing (TSP), 2019

The IEEE 802.11 standard provides specifications of medium access control (MAC) layer for VANET. ... more The IEEE 802.11 standard provides specifications of medium access control (MAC) layer for VANET. The performance can be optimized by optimizing contention window size. In this paper, to optimize the performance in VANETs three different artificial neural network (ANN) algorithms are used to find the optimum contention window (CW) size which are Particle Swarm Optimization (PSO), Differential Evolution Algorithm (DEA) and Artificial Bee Colony Algorithm (ABCA). Performance comparison among PSO, DEA, ABCA and traditional MAC based on IEEE 802.11 is provided. The simulation results show that the ANN algorithms improve the communication reliability by increasing the throughput and decreasing the packet dropping rate (PDR).

A Blockchain-Based Emergency Message Transmission Protocol for Cooperative VANET

IEEE Transactions on Intelligent Transportation Systems, 2021

The Industrial Internet of Things (IIoT) is creating a massive impact in a wide range of applicat... more The Industrial Internet of Things (IIoT) is creating a massive impact in a wide range of applications. In addition, with the forthcoming 5G and 6G technologies, vehicular ad-hoc networks will have pioneer advancements. However, security concerns are not well addressed, as vehicular networks should be deployed at a large scale. To address the security concerns, especially to ensure secure emergency message transmission, a blockchain-based protocol is proposed in this paper, where one of the blockchains is to store the authentication information of the vehicle, and another one to store and distribute blockchain services. Experimental analysis revealed that the proposed blockchain-based protocols are superior than the existing ones in terms of several metrics

IEEE Access, 2020

Recently, a novel cluster-based medium access control (CB-MAC) protocol has been proposed for veh... more Recently, a novel cluster-based medium access control (CB-MAC) protocol has been proposed for vehicular ad hoc networks (VANETs). Though performance of CB-MAC protocol is affected by cluster size, no mechanism is provided to manage cluster size efficiently. In this paper, the performance of CB-MAC protocol is optimized for VANETs by optimizing transmission probability with cluster size. Each vehicle should adopt the optimum transmission probability in the cluster which can be obtained by tuning the number of clusters in VANET. Therefore, optimum number of clusters is defined based on the number of vehicles in VANETs. An analytical study based on Markov chain model is provided. Optimum transmission probability, and optimum number of clusters expressions are derived. The microscopic mobility model is generated in SUMO for practical scenario. Simulation results are presented which verify analytical (theoretical) analysis and show that the performance of CB-MAC protocol is maximized in terms of throughput, packet dropping rate (PDR), and delay. Throughput is remarkably increased, whereas PDR and delay are decreased.

Gazi Üniversitesi Mühendislik-Mimarlık Fakültesi Dergisi, 2020

 CSMA/CA and RTS/CTS based MAC protocol for VANETs  Markov chain model based analytical analysi... more  CSMA/CA and RTS/CTS based MAC protocol for VANETs  Markov chain model based analytical analysis  Throughput, packet dropping rate (PDR) and delay analysis In IEEE 802.11, distributed coordination function (DCF) is the fundamental access technique, which employs a carrier sense multiple access with collision avoidance (CSMA/CA) mechanism to access the medium. In addition, request to send (RTS)/ clear to send (CTS) mechanism is used to overcome hidden vehicular nodes problem. In the figure A, CSMA/CA mechanism in (a) and RTS/CTS mechanism in (b) are shown. Figure A. CSMA/CA mechanism (a) and RTS/CTS mechanism (b) Purpose: In this paper, an analytical model is developed to evaluate the performance of the IEEE 802.11 MAC for VANETs. Markov chain model based analytical analysis is presented to investigate the performance. Theory and Methods: The algorithm of CSMA/CA and RTS/CTS mechanism are presented. An analytical model based on Markov chain is developed to scrutinize the performance of IEEE 802.11 MAC Protocol for VANETs. Relationship among performance metrics and the IEEE 802.11 MAC parameters, such as the contention window, retransmission limit, number of vehicles, velocity of vehicles, etc. are provided. Successful transmission probability, collision probability, throughput, PDR and delay expressions are derived. Numerical results are demonstrated to verify the accuracy of the analytical model and to investigate the IEEE 802.11 DCF performance in VANETs. Comparison between CSMA/CA and RTS/CTS access mechanisms is presented. Results: When the number of vehicles increases, throughput increases until a point then starts to decrease because more collisions will occur due to contention in the channel for the transmission of packet. When the number of vehicles is high, the RTS/CTS access technique is more successful than the CSMA/CA technique because it helps to solve the hidden node problem. Throughput decreases with the increment of vehicles velocity because topology changes rapidly which makes communication unstable. The reliability of data transmission depends on PDR which depends on successful transmission probability and maximum retransmission limit. If the PDR is low, the reliability of the transmission is high. Delay increases with increase of the number of vehicles because more packets will contend to transmit which will increase the probability of channel busy and collision. Conclusion: In this paper, we modeled and analyzed the IEEE 802.11 MAC protocol for VANETs. We considered both CSMA/CA and RTS/CTS access mechanisms. The algorithm of both access mechanisms are provided. Markov chain model based analytical analysis and numerical results are presented. Mobility is the key characteristics of VANETs, which is considered. To improve the communication quality, throughput should be increased and delay should be decreased; and PDR should be increased to increase the reliability of communication which can be achieved by increasing successful transmission probability, and decreasing channel busy probability and collision probability. Future studies include optimization and details performance analysis under channel fading and capture effect.

Machine Vision-based Expert System for Automated Cucumber Diseases Recognition and Classification

2021 International Conference on INnovations in Intelligent SysTems and Applications (INISTA)

Sustainability

Existing research shows that Cluster-based Medium Access Control (CB-MAC) protocols perform well ... more Existing research shows that Cluster-based Medium Access Control (CB-MAC) protocols perform well in controlling and managing Vehicular Ad hoc Network (VANET), but requires ensuring improved security and privacy preserving authentication mechanism. To this end, we propose a multi-level blockchain-based privacy-preserving authentication protocol. The paper thoroughly explains the formation of the authentication centers, vehicles registration, and key generation processes. In the proposed architecture, a global authentication center (GAC) is responsible for storing all vehicle information, while Local Authentication Center (LAC) maintains a blockchain to enable quick handover between internal clusters of vehicle. We also propose a modified control packet format of IEEE 802.11 standards to remove the shortcomings of the traditional MAC protocols. Moreover, cluster formation, membership and cluster-head selection, and merging and leaving processes are implemented while considering the sa...

IEEE Access

Mobile communication systems are always in continuous evolution due to the demands of the end-use... more Mobile communication systems are always in continuous evolution due to the demands of the end-users using this technology. Therefore, before the possible launch of 5G, some technologies have opened the way to the new mobile communication system. The need for technologies that provide more comfort to users has led to the construction of complex communication systems that were only science fiction decades ago. The information society in which we are now immersed has been the result of constant progress over time. In this paper, a survey of multiple access schemes for next-generation wireless communication systems is presented. Multiple access schemes are reviewed for possible use in next-generation wireless communication systems such as orthogonal multiple access (OMA), non-orthogonal multiple access (NOMA), and delta-orthogonal multiple access (D-OMA), etc. General comparisons of 1G to 6G are presented. Different types of OMA are explained, and then orthogonal frequency division multiple access (OFDMA) is chosen as an example of the OMA scheme to compare with NOMA and D-OMA. There are two types of NOMA: power-domain and code-domain, which are discussed and compared. Simulation results are presented, and a comparison among different access schemes is provided. INDEX TERMS D-OMA, multiple access schemes, next-generation wireless communication systems, NOMA, OFDMA, OMA.

IEEE Access

In vehicular ad hoc networks (VANETs), mobility between vehicles can cause rapid topology changes... more In vehicular ad hoc networks (VANETs), mobility between vehicles can cause rapid topology changes with frequent disconnections, which result in collisions and packet losses that make communications unstable. Alternatively, cooperative transmission can increase the reliability of communication by eliminating these problems in VANETS. In heavy traffic conditions, carrier sense multiple access with collision avoidance (CSMA/CA) suffers from collision, and it is not effective when high data rate is required. Therefore, orthogonal frequency division multiple access (OFDMA) is proposed. With the use of OFDMA, throughput is increased and delay is decreased by reducing the probability of collision in high traffic scenario. In this study, a novel OFDMA based efficient cooperative MAC protocol (OEC-MAC) is proposed for VANETs. Subcarrier channels assignment and access mechanisms are provided. The mechanism is presented not only for choosing the appropriate transmission mode but also for selecting the optimum relay. New control messages are defined to support cooperative communication. The performance of OEC-MAC protocol is examined by providing analytical analysis based on Markov chain model. Numerical results are demonstrated, which reveal that OEC-MAC protocol ensures a remarkable increase in throughput and also satisfies the strict delay requirement of 100 ms in VANETs for safety messages (sm). In addition, communication reliability is increased by reducing the packet dropping rate (PDR). Numerical results are compared with existing protocols, and a quantitative comparison is provided. It has been seen form results that proposed OEC-MAC protocol is better than existing schemes, especially under heavy traffic scenarios.