International Journal of Sensor Networks (41 papers in press)

Regular Issues

• Recent Advances in Wireless Sensor Networks with Environmental Energy Harvesting
  by Lei Shu, Wanjiun Liao, Jaime Lloret, Lei Wang 
  Keywords: .
  
  
• An IoT Based Efficient Multi-Objective Real-Time Smart Parking System  
  by Hitesh Mohapatra, Amiya Kumar Rath 
  Abstract: Nowadays, finding a parking place is the most frustrating job for drivers in many of the major cities. The improper parking invites many negative side effects on urban roads. In this work, we propose a unique smart parking analyst (SPA) model for adequate parking. The SPA broadly focuses on two types of parking spaces such as public and private space-based smart parking. Unlike existing models, our proposed plan does not give any additional burden on drivers, like carrying a smartphone or driver has to be a techie. Here, we broadcast all the sensor-based real-time parking information through LED displays at the appropriate point for the convenience of all types of people. Additionally, we propose an efficient clear crowd (CC) method which helps to make available parking space most of the time and to generate more revenue from parking areas in case of excessive use. Though this work does not support smart phone-based parking solutions, still we have provided a few additional services through smartphone users as it is a demand of time which is not a core part of the SPA. The result of our execution shows that it achieves high efficiency of 94.23% in judging the appropriate parking slots and high accuracy of 91.76% in making free the occupied parking area. On the other hand the proposed model generates revenue of 1.18 times than the existing conventional parking model.
  Keywords: Wireless Sensor Network; Smart Parking; Revenue Generation; Internet of Things.
  
  
• Performances Analysis of UAV-assisted Wireless Powered Sensor Network  
  by Jing Yan, Liming Wang 
  Abstract: In a wireless sensor network (WSN), the key restrictive factor for network service performance is the energy replenishment of energy-constrained sensor nodes. Moreover, utilizing radio frequency signals for wireless energy transmission is regarded as an effective method for energy-constrained sensor nodes to charge. Furthermore, UAV (Unmanned Aerial Vehicle) has attracted increased attention to wireless sensor networks because of their high flexibility and low-cost by improving energy efficiency through trajectory planning while data collection. In this paper, we propose a novel UAV-assisted wireless rechargeable sensor network (WRSN), where the energy-constrained sensor nodes firstly harvest energy from the RF (Radio Frequency) signals of UAV in the downlink and then forward the information to the sink node with harvesting energy. The closed-form expressions of system throughput and outage probability in AF (Amplify and Forward) and DF (Decode and Forward) modes are both derived. Additionally, the theoretical derivation model is validated with simulation results. In particular, the results show that the DF protocol is superior to the AF protocol with lower probability and higher throughput. Besides, the influences of energy harvest time, the transmission power of UAV, and target signal-to-noise ratio on the throughput and outage probability are systematically analyzed.
  Keywords: Wireless Sensor Network; UAVs; Relay; Outage Probability; Throughput.
  
  
• Multi-Armed bandit Algorithms Over DASH for Multihomed Client  
  by Ali Hodroj, Marc Ibrahim, Yassine Hadjadj-Aoul 
  Abstract: There is an expanding request from the mobile clients of video traffic which has come to over the most recent two years the greater part of all the mobile data traffic. The challenge of providing the clients excellent video streaming is expected principally to the constrained transfer speed which makes it important to misuse the rising decent variety of mobile video spilling and get to systems. For enhancing the video quality received by \"multi-homed client\" (i.e., clients with multiple network interfaces), a network selection algorithm based on the Multi-Armed Bandit heuristic is proposed on top of the most broadly utilized standard for video streaming Dynamic Adaptive Streaming over HTTP (DASH).rnFor choosing the best network at each progression powerfully, DASH gives mobile video quality dependent on the apparent exhibition from the pre-owned system association through the Adaptive Bitrate Rules (ABR) without investigating the system conditions through the other network(s) which could give better quality. Subsequently, a few alterations for DASH ABR is required to enhance the video quality.rnTwo of the MAB algorithms (UCB and Epsilon Greedy) were embraced for improving MPEG-Dash. The investigations are performed through a proving ground execution to show that UCB surpasses Epsilon Greedy, in stable system conditions, regarding goodput received by the Dash customer. Additionally, UCB can discover the harmony between investigating new choices, and abusing the triumphant variation.
  Keywords: DASH; Multi-homed; video streaming.
  
  
• An Improved DV-Hop Algorithm Based on Differential Simulated Annealing Evolution  
  by Fei Tang, Witold Pedrycz 
  Abstract: To improve the localization accuracy of a DV-Hop localization algorithm in the wireless sensor networks with irregular network topologies, in this study, we propose an improved DV-Hop algorithm based on differential simulated annealing evolution (DSAE). The distance between the unknown node and anchor are main element in the phase of calculating the coordinate of the unknown node, but this is calculated by average hop distance (HD). So, the key behind improving the localization accuracy is to calculate the hop distance between the anchor nodes. In this paper, we innovatively divide the hop distance into the global single-hop average HD between beacon nodes, the corrected the average HD between anchor nodes and the local single-hop average HD between anchor nodes. The defect of computation method of HD, only considering the average HD, draws forth this originality. Combining three kinds of HDs, DSAE based on the HC threshold is used to estimate the average HD. The simulation results show that the improved DV-Hop algorithm can decrease the error of localization and significantly outperforms state of the art localization algorithm by 37.38% in terms of the localization error.
  Keywords: wireless sensor networks; the global single-hop average HD; the corrects the average HD; the local single-hop average HD; differential simulated annealing evolution algorithm.
  
  
• Analysis and Modeling of iBeacon Wireless Signal Propagation in Multiple Environments  
  by Luchuan Zeng, Zhifei He, ZheRui Tan, Renliang Geng, Menghua Liu, Linglin Xia, Deyu Lin 
  Abstract: IBeacon positioning accuracy is usually influenced by its signal quality in practical environments. The purpose of this study is to provide users with a reasonable iBeacon networking deployment scheme to improve the accuracy of positioning. We explore the characteristics of iBeacon signal propagation and existing propagation path loss in common environments (corridor, playground, classroom). Firstly, the changes of Received Signal Strength Indicat (RSSI) value of iBeacon wireless signal under three environments are collected, and then the signal samples are filtered numerically. Secondly, a simplized single-slope and a double-slope propagation models are developed to simulate iBeacon signal propagation. Finally, the developed models are used to carry out regression analysis on the sample data under different scenarios, and the best applicable scenario of the two models is determined according to the results. In conclusions, based on the simulation results of the propagation model, this study provides some suggestions for users to deploy ibeacons indoors or outdoors.
  Keywords: iBeacon; propagation characteristics; logarithmic distance model; received signal strength indicat (RSSI); multi-environment.
  
  
• An Inertial and Global Positioning System based Algorithm for Ownship Navigation  
  by Ihsan Ullah, Bizzat Hussain, Shafaq Nisar, Uzair Khan, Mohsin Ali, Sajjad Manzoor 
  Abstract: In this paper a fusion algorithm for Global Positioning Systems (GPS) and Inertial Navigation System (INS), using Inertial Measurement Unit (IMU), is proposed for ground vehicle trajectory estimation during a GPS outage. As a standalone system an INS has its limitations and an error growth as a result of bias and drift inherent to this sensor restricts its application. A GPS can be used for vehicle navigation flawlessly, however the navigation performance may suffer due to intentional or unintentional GPS signal outage. The proposed GPS-INS fusion algorithm is able to handle any GPS blackout, restrict the INS error development and estimate a precise ownship position while utilizing information from two route frameworks i.e. the GPS and the INS. In order to validate the proposed GPS-INS based Matched State Cascaded Fusion (MSCF) algorithm, it's root mean squared error (RMSE) of the developed algorithm is analyzed. It is proven using experiments and simulations that a decrease in critical measure of error has been accomplished with the proposed algorithm.
  Keywords: Sensor Fusion; Global Positioning Systems (GPS); Inertial Navigation System (INS) and Inertial Measurement Unit (IMU).
  
  
• The Flaws of Internet of Things (IoT) Intrusion Detection and Prevention Schemes  
  by Saher Ghayyad, Shengzhi Du, Anish Kurien 
  Abstract: For years, the Internet has been a major tool in our lives but is always a target for hackers who intend to take advantage of individuals, corporates, governments, banks and other institutions. As the Internet evolved to include the Internet of Things (IoT), each physical system with an IP address on this wide network can communicate without human intervention. These cyber-physical systems can vary from a smart grid to a smartphone and are attractive to hackers leading to a high risk of compromise of these systems on core infrastructure and network communication security. This paper addresses a Denial-of-Service attack (DoS), one of the major attacks on IoT Networks. The flaws are discovered in existing IoT intrusion detection and prevention schemes combating DoS attacks on Wireless Sensor Networks (WSN). Live DoS attacks on IoT Sensors are demonstrated using Kali Linux Platform. Moreover, the flaws in existing solutions are revealed using a demo Cisco Meraki MR33 and a more effective intrusion detection scheme is proposed by an active in-depth-defence strategy against DoS attacks.
  Keywords: Internet of Things (IoT); Hackers; Denial-of-Service (DoS) Attack; Wireless Sensor Networks; Intrusion Detection and Prevention Schemes; Cisco Meraki MR33; Air Marshal.
  
  
• Performance optimization of multichannel MAC in large-scale wireless sensor network  
  by Chuchu Dong 
  Abstract: Efficient multichannel medium access control (MAC) protocols can significantly prolong the lifetime of sensor networks by reducing the energy consumption of packet transmission among neighbor nodes. In this paper, an energy-efficient Prediction-based Multichannel MAC protocol (PM-MAC) is proposed for large-scale wireless sensor networks. PM-MAC minimizes sensor node's idle listening time without introducing any multihop time synchronization and channel assignment overhead by introducing a prediction mechanism of the target node's wakeup channel and wakeup time. PM-MAC introduces a dynamic channel allocation to achieve precise and quick resynchronization when a prediction error in the wakeup time occurs. In addition, in PM-MAC, the load can be well balanced on all channels. Finally, its prediction-based retransmission mechanism can achieve more energy efficiency than traditional strategies such as Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) in resolving severe wireless collisions caused by concurrent traffic in large-scale sensor network. The PM-MAC not only reduces multihop packet latency and energy consumption, but also increases network capacity and throughput. Experimental results confirm the outstanding performance of PM-MAC in all testbeds.
  Keywords: wireless sensor network; MAC protocol; channel assignment; energy efficiency.
  
  
• Hybrid Visible Light Communication Power Optimization in Indoor Environment  
  by Choong Florence, Tan Ching Han, Yandan Lin 
  Abstract: Traditional way of handling more traffic is by having higher cell density, higher spectral efficiency and carrier aggregation. Many network optimizations have been put in place to overcome this high growth in data traffic demand. However, the network electricity consumption also increases tremendously. Hybrid visible light communication (HVLC) rides on solid-state light emitting diode lighting infrastructure with higher energy efficiency. HVLC has the advantages of high data rates, higher bandwidth, un-licence requirement, lower cost and more energy efficient. This paper focuses on recent breakthrough and advancement in HVLC especially for indoor applications. Two indoor lighting topologies were studied in detail in order to determine their power optimization performances. The power optimization through linear programming methods were used to simulate and compare the performance of square and ring topology design. The square topology showed better performance as compared to ring topology. Also, the number of users versus received power and channel assignments performance is also better for square topology. The findings demonstrated the feasibility of HVLC for indoor application.
  Keywords: HVLC; radio frequency; visible light communication; square topology; ring topology; bandwidth; power optimization; energy efficiency; lighting; LED.
  
  
• An IoT Smart Clothing System for the Visually Impaired using NFC Technology  
  by Reham Alabduljabbar 
  Abstract: The selection of appropriate clothing to match ones daily life is an important ritual for individuals across the globe. But this can be a Herculean task, especially for the visually impaired. Together with the rise of the Internet of Things (IoT) paradigm and enabling technologies, solutions to improve the quality of life for visually impaired people have arisen. This paper proposes an IoT-based smart clothing system (EZwear) to enable visually impaired individuals to select and find appropriate clothing within their closets. The main underlying technical components in the solution are the use of an NFC (Near Field Communication) and a smartphone and its applications. By combining these technologies, we can transform a smartphone into an NFC reader that can provide sound information to the visually impaired user. The system enhances the ability of the visually impaired person to independently and comfortably manage their closets. The results show that the system performed reasonably and achieved the usability requirements.
  Keywords: IoT; Internet of Things; visually impaired; smart clothing; mobile application; NFC; assistive technology; sensors; network.
  
  
• Optimal fusion rule for distributed detection with channel errors taking into account sensors unreliability probability when protecting coastlines  
  by Parfenov Vladimir Ivanovich, Le Van Dong 
  Abstract: In this paper, algorithms that make decisions on the presence or absence of penetration on a protected object with both ideal and non-ideal communication channels are synthesized and analyzed. Local sensor decision rules based on an energy detector and its performance characteristics are presented. We determine the dependencies of the total error probability on the energy parameter taking into account the energy emitted from the target at the level of local sensors and the channels signal-to-noise ratio. The gain of the optimal fusion rule in efficiency compared to known fusion rules such as the LRT-BER and Chair-Varshney fusion rule is shown. The detection algorithm under possible sensor failure and its detection performance is also presented. With the unknown target location on a coastline, the detection rules are given and the detection performance is analyzed
  Keywords: wireless sensor networks (WSN); sensor; coastline; Bézier curve; decision fusion; likelihood ratio test; total error probability; unreliability probability; location estimation; generalized maximum likelihood method.
  
  
• Grid-based Lane Identification with Roadside LiDAR Data  
  by Jianqing Wu 
  Abstract: Lane identification is important for many different applications, especially for connected-vehicle technologies. This paper presents a new method for lane identification with the roadside Light Detection and Ranging (LiDAR) serving connected-vehicles. The proposed lane identification method is a revised grid-based clustering method (RGBC). The whole procedure includes background filtering, object clustering, object classification, and RGBC. A location matrix (LM) can be generated to store the location of each lane. The performance of the proposed method was evaluated with the data collected from the real world. The testing results showed that the RGBC can locate 96.73% of vehicles to the correct lane. The RGBC was also compared to the state of the art, showing that the computational load for RGBC is lowest compared to other algorithms, with a cost of slightly reduced accuracy. The time delay for real-time data processing is less than 0.1 ms, which can provide the High-Resolution Micro Traffic Data (HRMTD) for connected-vehicles.
  Keywords: Lane identification; Roadside LiDAR; Grid-based Classification.
  
  
• Trustworthy Collaborative Trajectory Scheme for Continuous LBS  
  by Yuan Tian, Biao Song, Miada Murad, Najla Al-Nabhan 
  Abstract: With the high demand for using location-based services (LBSs) in our daily lives, the privacy protection of users trajectories has become a major concern. When users utilize LBSs, their location and trajectory information may expose their identities in continuous LBSs. Using the spatial and temporal correspondences on users trajectories, adversaries can easily gather their private information. Using collaboration between users instead of location service providers (LSPs) reduces the chance of revealing private information to adversaries. However, there is an assumption of a trusting relationship between peers. In this paper, we propose a trustworthy collaborative trajectory privacy (TCTP) scheme, which anonymizes users trajectories and resolves the untrustworthy relationship between users based on peer-to-region LBSs. Moreover, the TCTP scheme provides query content preservation based on a fake query concept in which we conceal the users actual query among a set of queries. The results of several experiments with different conditions confirm that our proposed scheme can protect users trajectory privacy successfully in a trustworthy and efficient manner.
  Keywords: Continuous Location-based Services; Anonymity; Trajectory Privacy Protection; Fake Queries; K-anonymization.
  
  
• Object detection algorithm combined with dynamic and static for air target intrusion  
  by Yi Xiao, Faming Shao, Fanjie Meng, Jiqing Luo 
  Abstract: The infrared detection of target intrusion usually faces the problems of complex background and insufficient brightness. This paper proposed a method combining dynamic detection and static detection, which is mainly composed of adaptive local contrast module (ALCM), interval frame semantic layered module (IFSL) and enhancement network module. ALCM, as a static method, uses adaptive sliding box to traverse the original image to obtain relatively simple background targets. As a dynamic method, IFSL can effectively separate moving targets from the background based on spatial semantic information under dynamic conditions. The function of the enhanced network module is to suppress the background clutter and highlight the target. Compared with the traditional detection method, the SNR of the proposed method is improved by 8.65%, and the computing speed is improved by 7.14%. This strongly proves that the method has high detection rate and detection efficiency in this case.
  Keywords: infrared target; static detection; dynamic detection; feature fusion; enhanced network.
  
  
• Energy-efficient Time Synchronization Based on Odd-Even Periodic Data Transmission and Acknowledgement in Wireless Sensor Networks  
  by Chuang Wang, Zhili Zhang 
  Abstract: In the working process of wireless sensor networks (WSNs), it is challenging to realize precise and energy-efficient time synchronization on resource-constrained WSNs nodes. In this paper, a fusion method of time synchronization with periodical data transmission and acknowledgement is proposed for WSNs. Moreover, different response intervals are generated according to the parity characteristic of the measurement data's serial number. The maximum likelihood estimators (MLE) of clock skew and fixed delay, and the simplified MLE of clock skew under the Gaussian random delay are derived. Meanwhile, the corresponding Cramer-Rao Lower Bound is calculated. The two proposed MLEs of clock skew show that both of them can work independently of the fixed delay. Simulation results verify the efficiency of these two clock skew estimators and fixed delay estimator, especially the performance and effectiveness of the second simple and practical MLE.
  Keywords: Time Synchronization; Clock Skew Estimation; Energy Efficiency; Timed Response; Wireless Sensor Networks.
  
  
• A Collaborative Charge Scheduling Scheme for Electric Vehicles (EV) Based on Charging Time and Resource Cost-awareness  
  by Mahfuzulhoq Chowdhury 
  Abstract: To reduce the greenhouse gas emissions problems of traditional fuel vehicles, Electric vehicles (EVs) are regarded as a promising transportation solution by industry peoples. Although EVs' performances are limited due to their limited battery power, large travelling distance during their journeys, charging delay for service, and resource price. To improve the EV's performance, this paper presents a charging time and resource cost- aware collaborative EV charging policy that selects not only a suitable charging station but also assigns timeslot for charging-discharging operation. In this paper, a decentralized EV charging/discharging network architecture is proposed in which the EV does not only communicate with the local cloud server by using the traditional vehicular network but also utilizes the EV-to-charging station and EV-to-EV interaction. The simulation results indicate that the proposed charging scheduling policy results in a better charging requirement satisfaction ratio, charging delay, and resource costs than the compared traditional schemes.
  Keywords: Electric Vehicles (EV); Charging delay; Charge scheduling; Satisfaction ratio, Utility; Waiting delay; Resource allocation; Revenue-to-required time ratio; Elapsed time, Resource cost.
  
  
• IoT Networks for Monitoring and Detection of Leakage in Pipelines  
  by Seham Bakheder, Ghadah Aldabbagh, Samar Alkhuraiji, Nikos Dimitriou, Mai Fadel, Helen Bakhsh 
  Abstract: Pipelines have been an important means of oil transport in recent years, especially in Saudi Arabia. Since oil pipelines have extensive length, tracking them is a critical task. Therefore, monitoring pipeline leaks has become a significant field of intelligent sensing systems. There are many challenges when monitoring long-distance pipelines, requiring energy efficient. Wireless sensor networks (WSNs) deployed in oil pipelines provide solutions to address these challenges, but various issues must be considered, such as costs, scalability, and delay issues for monitoring systems. The recent advances in Internet of things (IoTs) and the new LPWAN capabilities have promising benefits over monitoring systems. This paper investigates WSN systems in oil pipelines with IoTs technologies. Also, it presents a LoRa as an LPWAN single-hop model for monitoring aboveground oil pipelines. The LoRa model is evaluated by using two scenarios and analyzing the scalability and capacity of the LoRa and discussing the result.
  Keywords: Internet of Things IoT; WSN; LPWAN; LoRa; Long range; Low power.
  
  
• Research on Abnormal Node Detection in a Wireless Sensor Network Based on Random Matrix Theory  
  by Jibao Hu 
  Abstract: Because the traditional detection methods have the problems of low recall and precision and long detection time, this paper studies a method of abnormal node detection in a wireless sensor network(WSN) based on random matrix theory. This method uses particle swarm optimization to improve DV-Hop, and uses the improved DV-Hop method to locate WSN nodes. According to the spatiotemporal characteristics of WSN data, a data matrix is built, and the dimensionality of the data matrix is reduced by using a random matrix. The node attributes are judged according to the element correlation between multiple matrices to realize abnormal node detection in a WSN. The test results show that the average recall rate and recall rate of this method are 97.0% and 97.2% respectively, and the detection time is always less than 0.5s, so the practical application effect is good.
  Keywords: Random matrix theory; WSN; Abnormal nodes detection; DV-Hop; Particle swarm optimization.
  
  
• A Self-Organizing Organizational Paradigm for Using Multi-Agent Systems in Traffic Control Application of VANETs  
  by Mir Bagher Hosseini, Amin Rahmanzadeh, Eslam Nazemi 
  Abstract: The growth of small systems towards ultra-large-scale ones gradually leads us to leave the control of those systems to themselves. Autonomic computing and the self-adaptation concept have come to help. One of the sub-categories of autonomic computing is self-organization, which is suitable for distributed systems. By controlling a distributed system using agents and turning it into a multi-agent system, we can use self-organization mechanisms to enable the system to control itself. Vehicular Ad-Hoc Networks (VANETs), which can be considered as multi-agent systems, have many applications in the areas of safety and comfort of passenger vehicles. Due to the characteristics of VANETs, it is not easy to manage and maintain them manually. The dynamic nature of these networks makes automatic management necessary. VANETs characteristics, such as including vehicles with computing and energy resources, bring us to the idea of assuming them as multi-agent systems. Having this in mind, we can provide the required automatic management by adding self-organization mechanisms to VANETs, as they are multi-agent systems. In this paper, we present Team-Coalition Traffic Control (TCTC), a self-organizing organizational paradigm to add self-organization features to VANETs for traffic control. The presented organizational paradigm works without any need for roadside traffic control infrastructure, and it is fully distributed. The goal of this paradigm is to reduce the waiting time for vehicles to pass an intersection.
  Keywords: Multi-Agent Systems; VANETs; Autonomic Computing; Self-adaptation; Self-organization; Traffic Control.
  
  
• Real-Time monitoring of Social Distancing with Person Marking and Tracking System using YOLO V3 model  
  by Pandiyan P, Rajasekaran Thangaraj, Subramanian M, Rahul R, Nishanth M, Indupriya Palanisamy 
  Abstract: The global economy has affected enormously due to the spread of coronavirus (COVID-19). Even though, there is the availability of vaccines, social distancing in public places is one of the viable solutions to reduce the spreading of COVID-19 suggested by the World Health Organization (WHO) for fighting against the pandemic. This paper presents a YOLO v3 object detection model to automate monitoring of social distancing among persons through CCTV surveillance camera. Furthermore, this research work used to detect and track the person, measure the inter-person distance in the crowd under a challenging environment which includes partial visibility, lighting variations and person occlusion. Moreover, the YOLO V3 model is experimented with Darknet53 and ShuffleNet V2 backbone architecture. Compared with Darknet53 architecture, ShuffleNet V2 achieves better detection accuracy tested on Custom Video Footage Dataset (CVFD), Oxford Town Centre Dataset (OTCD) and Custom Personal Image Dataset (CPID) datasets.
  Keywords: Deep Learning; COVID-19; Social Distancing; Surveillance Camera; Crowd Counting; Computer Vision.
  
  
• Dynamic Bandwidth Estimation and Congestion Avoidance based on Network Traffic in Mobile Cloud  
  by TAMIZHSELVI S.P, Vijayalakshmi M 
  Abstract: Mobile cloud computing (MCC) plays a vital role in digital communication for delivering the network and media services such as live streaming, social network, search engine, GPS navigation, and email. While providing services, the smartphone faces many QoS challenges due to network traffic, bandwidth, congestion, delay, and packet loss. To solve the issues, we propose a novel framework, namely, Network traffic-aware dynamic bandwidth estimation and congestion avoidance in the mobile cloud. To handle the mobile network traffic, delay, and congestion, we propose three algorithms in the cloud, namely, Network Bandwidth Cloud Estimation (NBCE) algorithm, Cloud Estimated Queuing Delay (CEQD) algorithm, Cloud Bandwidth Congestion Avoidance (CBCA) algorithm. Firstly, NBCE utilizes the actual bandwidth based on different mobile network traffic. The second algorithm CEQD determines the delay to minimize the packet loss. Finally, CBCA reduces the congestion with the help of two parameters estimated bandwidth and queue length. The above algorithms were implemented in the public cloud Amazon Web Service (AWS) and evaluated. The experiments conducted in this work observed that NBCE utilizes the actual bandwidth of 88%, 80%, 67% for different network status such as low, medium, and high compared with existing TCP variants to provide improved network performance. CEQD minimizes the average delay to 20 ms when compared with other TCP algorithms. Finally, CBCA improves 5%, 4%, 4% goodput in different network traffic.
  Keywords: Network traffic; bandwidth estimation; queueing delay; congestion avoidance;rnmobile cloud; Quality of service; packet loss rate; throughput; goodput; congestion window;.
  
  
• Improved Bees Algorithm for the Deployment of Homogeneous and Heterogeneous Wireless Sensor Networks  
  by Hicham Deghbouch, Fatima Debbat 
  Abstract: Nowadays, countless applications benefit from the services provided by Wireless Sensor Networks (WSNs) in remote surveillance and data gathering. Coverage is considered an important Quality of Service (QoS) criterion for many of these applications. To ensure that the required QoS is achieved, the sensors must be placed in locations that optimise the area coverage and eliminate the coverage holes, especially when deploying sensors with heterogeneous sensing ranges. In this paper, a novel sensor deployment scheme based on the Improved Bees Algorithm (IBA) for optimising the area coverage in both homogeneous and heterogeneous WSNs is proposed. The IBA includes a neighbourhood shrinking procedure that aims to improve the local search efficiency and a site abandonment procedure for preventing the algorithm from the entrapment in a local optimum. Experiments show that the IBA delivers high-quality solutions and optimises the area coverage effectively compared with four state-of-the-art methods in homogeneous and heterogeneous WSNs.
  Keywords: wireless sensor networks; bio-inspired algorithms; metaheuristics; coverage redundancy; area coverage; simulation; optimisation.
  
  
• A quantum key injection scheme for mobile terminals based on commercial quantum key distribution  
  by Xiaohui Li, Dexin Zhu, Huan Wang, Lifeng Yang, Jianan Wu, Lijun Song 
  Abstract: In order to satisfy the demand of mobile secure communication for quantum keys, this study proposes a commercial quantum key distribution (QKD) based quantum key injection scheme for mobile terminals. It integrates a quantum network with a classic network, employs a quantum key injection device, and applies an encryption strategy to securely transmit the quantum key from the quantum network to the classic network for injection into a mobile terminal.Experimental results in a real quantum key distribution environment show that the fusion network runs stably, and the injection of the quantum key at the mobile terminal is realized effectively, which can meet the demands of mobile secure communication for quantum keys.
  Keywords: quantum key; mobile key injecting; commercial QKD.
  
  
• Motion Mode Recognition in Multi-storey Buildings Based on the Naive Bayes Method  
  by Litao Han, Lei Gu, Cheng Gong, Tianfa Wang, Aiguo Zhang 
  Abstract: When walking within a multi-storey building, pedestrians use a variety of modes of motion, such as going upstairs or downstairs, or walking on a plane. In each of these modes, the step size will be different, and this has a strong impact on the accuracy of pedestrian dead reckoning. In order to identify the patterns of movement in multi-storey buildings, we propose a new method of movement recognition based on smart phones. Firstly, the relationships between the patterns of indoor movement and the changes in the air pressure, acceleration and angular velocity data obtained from the built-in sensors of mobile phones are analysed. The naive Bayes method is then used to identify four different modes of motion: walking up and down stairs, moving on a landing and moving at a constant speed along a corridor. Our experimental results show that the recognition accuracy of our scheme reaches 95.82%.
  Keywords: accelerometer; barometer; gyroscope; motion mode recognition; naive Bayes; smart phone.
  
  
• Online Drone-based Data Gathering Strategies for Ground Sensor Networks  
  by Celia Yasmine TAZIBT, Nadjib ACHIR, Tounsia DJAMAH 
  Abstract: This paper proposes two path-planning schemes for data collection in WSN using a drone flying over the sensor nodes to collect their data. We assign a weight to each sensor node corresponding to its priority in the collection process. When the drone selects its destination node, it will choose the one having the highest weight. We have defined utility functions based on the sensor nodes' information disseminated in the Wireless Sensor Network (WSN) using the Optimized Link State Routing protocol (OLSR). The information required to compute the nodes' weight is added to the exchanged packets during the execution of OLSR. The first proposed strategy is Data-driven Data Gathering Strategy (DDG) which uses the amount of stored data in each sensor node buffer. A priority is given to the nodes having the most significant data amount to collect. The second strategy is called Time-driven Data Gathering Strategy (TDG) where the age of the data is considered.
  Keywords: Wireless sensor networks; unmanned aerial vehicles; data gathering; path planning.
  
  
• An IoT-based Scalable River Level Monitoring Platform  
  by Juan Acosta, Diego Mendez, Daniel Moreno, German Montanez, Luis Trujillo, Mauricio Escobar, Ignacio Gonzalez 
  Abstract: Due to extreme natural conditions, there is a clear necessity of cost-effective and scalable solutions to continuously monitor the environmental conditions in order to take precautionary actions. In this paper we present the design and implementation of an IoT-based solution for river level monitoring. The implemented system integrates 31 stations with communication capabilities to monitor the status of the Negro and Nare rivers. An embedded system has been designed and implemented from scratch into a single PCB, integrating ultrasonic sensors and power management. In order to consolidate and visualize the data, a cloud platform has been implemented, which is also in charge of generating alerts to local authorities and the population in general. The stations have an autonomy of 22 days in case of complete solar panel damage. The experimental results show that the river dynamics are perfectly captured in real-time, allowing the authorities to timely warn the population.
  Keywords: Embedded system; early warning system; floods; river level; IoT.
  
  
• Iot-based indoor access control and monitoring: a case study from the containment measures of the Covid-19 pandemic  
  by Sérgio Andrade, Rogério Negrão, Micael Fernandes, Fernando Costa, Marcos Seruffo 
  Abstract: The Covid-19 pandemic has led many serving environments to seek solutions to control people\'s access and avoid crowding in order to contain its spread, and to ensure the health and safety of users. Given the various current solutions, this paper presents a monitoring system that shows, in real time, via web, the status of people in closed environments. It uses Internet of Things (IoT) techniques for data interconnections and electronic components NodeMCU board and proximity sensors to monitor the entrance and exit of people in an enclosed environment, providing the statistics through an IoT platform (application) that can be installed in a mobile device (smartphone). This study highlights a low-budget system, shows the implementation of IoT platforms in the development of prototypes and the tests carried out in the academic service office.
  Keywords: Internet of Things; Covid-19; IoT Monitoring; IoT Platform; Prototypes.
  
  
• Random Binary Sequences Generation using Heartbeats for Cryptographic Keys in WBSNs  
  by Aditya Sinha, Judhistir Mahapatro, Bidisha Bhabani 
  Abstract: Heartbeats as a cryptographic key is an emerging biometric based authentication in Wireless Body Sensor Networks (WBSNs). Specifically, Random Binary Sequences (RBSs) are generated using heartbeats which serve as the key for encryption and decryption algorithms. Modern trend is to monitor the patients health in real-time (anytime and anywhere) and provide telemedicine remotely. Monitoring the patients physiological parameters is done using sensor devices attached to the patients body. The sensor devices then relay the information to the medical servers for diagnosis. These devices are very small and are resource constrained, so, implementing computationally heavy cryptographic algorithms inside these devices for secure transmission of data is a challenging task. Recent security measure is that of producing a 128 bit RBS using the heartbeats which is used as a cryptographic key to aid in secure communication. This takes around 30 seconds for computation which is quite time consuming. In this paper, a novel approach is discussed which helps in decreasing this 30 seconds latency. To generate a RBS, first cyclic block encoding is applied and then convolutional encoding on a single heartbeat to obtain 32 bit binary encoded value. Four consecutive heartbeats 32 bit encoded value is concatenated to obtain 128 bit RBS. The generated 128 bit RBS is subjected to various tests to verify the cryptographic key strength and is analyzed for optimal resource consumption.
  Keywords: Inter Pulse Intervals (IPIs); RR-intervals ; Cyclic Block Encoding ; Convolutional Encoding ; Random Binary Sequences (RBSs).
  
  
• Two-stage pricing strategy for personal cloud storage: Free trial and the cloud security risk  
  by Mengdi Yao, Donglin Chen 
  Abstract: A common approach to attract potential cloud users is to offer a two-stage pricing strategy to enhance the perceived value. This value is based on the willingness of diverse cloud users to pay and the market stages of cloud storage providers (CSPs). However, the risk of breaching cloud security in the free trial stage due to the sharing of personal cloud storage products (PCSPs) may decrease the number of cloud users. Consequently, the study proposes a two-stage pricing strategy to make a trade-off between the cloud security risk and the perceived value. Furthermore, it aims to uncover the conditions under different security risk coefficients. It selects the optimal pricing strategy to help CSPs determine the free trial time and optimal price. Our findings can provide helpful insight in devising an optimal pricing strategy by CSPs considering security risks, which assures the safety of PCSPs and benefits CSPs by increasing profits.
  Keywords: Personal cloud storage products; Two-stage pricing strategy; Free trial; Cloud security risk.
  
  
• A false deletion data tracking method based on Fisher information distance in Wireless Sensor Networks  
  by Wei Jing, Peng Wang, Ningchao Zhang 
  Abstract: To solve the shortcomings of traditional data tracking methods, such as low tracking efficiency, high error rates, high consumption, and so on, we propose a method based on Fisher information distance to track the deleted data in wireless sensor networks. The proposed method adopts a multilateral measurement technology to measure the geometric data and mutual position information among wireless sensors. It also adopts a Kalman filter to reduce noise interference during data processing. It selects the most suitable and pre-selected member component tracking cluster to realize data tracking of wireless sensor networks based on Fisher information distance. Experimental results show that the proposed method has high accuracy, noise elimination ability, and network energy consumption saving capability.
  Keywords: Fisher information distance; Wireless sensors; Deleted data by mistakes; Data tracking;.
  
  
• Message-Ferrying Delay-Tolerant Routing in Linear Wireless Sensor Networks  
  by Imad Jawhar, Sheng Zhang, Jie Wu, Nader Mohamed 
  Abstract: Due to linearity of a monitored structure, wireless sensor network (WSN) topology exhibits a linear form and the resulting network is named a linear sensor network (LSN). In order to communicate data from sensor nodes (SNs) to the sink, a multi-hop approach can be used. However, this would result in significant transmission energy loss, as the SNs would be involved in the transmission of their data as well as the data from other sensor nodes. In this paper, we introduce a ferry-based LSN (FLSN) model, where a ferry node such as a robot or other types of moving vehicles goes along the LSN, collects the data from the SNs and delivers it to the sink at the end of the network. Overall, this approach saves SN energy, increases network lifetime, and reduces transmission interference. Four ferry movement algorithms are presented, simulated and analyzed under various network conditions.
  Keywords: Routing; delay-tolerant networks (DTNs); mobile ad hoc networks (MANETs); wireless sensor networks (WSNs); ferry; monitoring.
  
  
• A Novel Skin-Inspired Model for Intelligent Object Recognition in Sensor Networks  
  by Aaron Rababaah 
  Abstract: Extensive research work has been conducted in the area of wireless sensor networks with high concentration on target detection or/and tracking. Although, there is some work dedicated to target classification, but the considered sensor modalities require inexpensive hardware and complex algorithms such as video, audio, radar, infrared, etc. Our solution to this problem is to propose a novel concept inspired by the human skin. It is well-known that skin possesses simple sensing receptors, compared to sophisticated ones such as vision, through which humans can not only detect a stimulus but can identify its type such as a needle, glass, table, ball, etc. analogues to this biological behavior, we propose a stimulus data modeling, characterization and classification in a simulated sensor network. The technical development of the proposed model is presented and validated via training a convolution neural network and was found to be effective and promising for future extensions.
  Keywords: Skin-inspired model; object recognition; object classification; intrusion detection; sensor networks; deep neural networks; convolution neural networks.
  
  
• A Practical Solution for Blockchain-Secured Sharing of Trustworthy Traffic Information in Vehicular Ad Hoc Networks  
  by Zhaowei Ma, Li Zhu, Xiantao Jiang, F. Richard Yu, M. Omair Shafiq, Jeremy James 
  Abstract: In vehicular ad hoc networks, data transmission and storage are unreliable due to various constraints such as limited physical resource and unsteady topology. As Blockchain has become a reliable data protection approach using consensus algorithm and distributed ledger, we propose a system in this paper, which employs Blockchain technology to secure the sharing of traffic information and holds profound significance for intelligent applications. Our system focuses on the real-time visual traffic information which is uploaded into Blockchain in frames via smart contracts. The sequence of frames is considered for integrity verification prior to the consensus and persistence in Blockchain. The system can dynamically adjust the transaction volume in terms of the frame types, and supports transcoding frames in Blockchain. Along with the fault tolerance and immutability of Blockchain, the traffic information can be solidly protected and thus traffic safety can be improved.
  Keywords: VANET; Distributed Ledger Technology; Blockchain; Smart Contract; Consensus.
  
  
• Simulation-based Usability Evaluation of Visually Impaired Outdoor Navigation Using Sensor Fusion  
  by Chathurika Silva, Prasad Wimalaratne 
  Abstract: Conducting evaluation experiments with assistive navigation in real-life environments with visually impaired subjects is challenging for several reasons. Hence simulation-based usability evaluation experiments are a pragmatic and cost-effective approach in such studies. This study presents sensor fusion in a virtual simulation of assistive navigation, including obstacle detection, localization, and motion planning. The obstacle detection involves a complementary sensor fusion approach to detect static and dynamic obstacles via vision and obstacle sensing. Localization is carried out using Kalman filter-based sensor fusion of measurement data acquired by inertial measurements using an accelerometer and gyroscope as well as Global Positioning System (GPS) data of the visually impaired navigator. Precise motion planning for local and global navigation is based on the fused signals through obstacle detection and localization modules. The evaluation showed that experiments effectively estimate the trajectory of a visually impaired navigator by fusing the heterogeneous sensor measurements in a virtual environment.
  Keywords: blind navigation; sensor fusion; perception; localization; assistive technology; motion planning; simulation.
  
  
• Virtual Resource Mapping in Wireless Sensor Networks Based on the Maximum Independent Link Set  
  by Danjun Deng 
  Abstract: To solve the problems of low mapping success rate, high mapping energy consumption, and low conversion rate of high-dimensional data existing in traditional methods, propose a virtual resource mapping method based on the maximum independent link set in this paper. We adopt a vector space model to reduce the dimensionality of the virtual wireless sensor networks(WSNs) resource data. We also adopt a support vector machine to input the dimensionality reduction results into the resource feature space for resource classification to obtain the independent link set and label in virtual links of the WSNs. According to the maximum independent link set, we design the network virtual resource mapping process to complete the resource mapping. Experimental results show that, compared with other methods, our method has a higher success rate of resource mapping, lower energy consumption, and higher conversion rate of high-dimensional data.
  Keywords: Maximum independent link set; WSNs; Virtual resource mapping; Resource classification; Label the semantic.
  
  
• A COMPARATIVE STUDY OF MOBILITY MODELS FOR FLYING AD-HOC NETWORKS  
  by Juhi Agrawal, Monit Kapoor 
  Abstract: Flying Ad-hoc Network (FANET) consists of cooperative Unmanned Aerial Vehicle (UAVs) that form an ad-hoc network to accomplish an assigned task. The mobility of the UAVs plays a dominant role as the performance of FANETs is directly connected to the mobility of UAVs. To this end, this paper presents an extensive review of mobility management models of FANETs. There is limited work presented in previous survey as most of the survey papers are more focused on routing protocols. The novelty of this work is that we perform taxonomy and comparative analysis of various mobility models of FANETs. The comparison study of all FANET mobility models has been performed based on various network characteristics. Later, we also discuss the strengths, and weaknesses, of each mobility model. Furthermore, open issues, challenges, and some future directions for research in the field of FANETs have been discussed which shall be useful for further research.
  Keywords: UAV; FANET; Mobility models; Connectivity; Area coverage.
  
  
• Leak Detection and Localization on a Gas Pipeline using the Gradient of Squared Pressure  
  by Ghassan Alnwaimi, Hatem BOUJEMAA, Feras Alfosail, Nebras M. Sobhani 
  Abstract: In this paper, we suggest a new algorithm for leak detection and localization on gas pipeline. We decompose the pipeline in different sections of length L. We put two pressure sensors at the beginning of the studied section at location x=iL and two other pressure sensors at the end located at x=(i+1) L where i=0,,N-1 is the number of the studied section of pipeline. We also use two mass flow rate sensors at the beginning and end of each section. Our algorithm uses the Gradient of squared Pressure to locate the leak. We show that our new algorithm allows to locate the leak with 1.2% error in distance. We tested our algorithm on a pipeline of length 15km and the average error was around 180m. Therefore, the location error is around 180/15000=1.2%.
  Keywords: Wireless Sensors; Leak localization; Gas pipeline; Pressure sensors; Mass flow rate sensors.
  
  
• A Nonlinear Outlier Detection Method in Sensor Networks Based on the Coordinate Mapping  
  by Wei Jing, Peng Wang, Ningchao Zhang 
  Abstract: This paper designs a nonlinear outliers detection method based on the coordinate mapping. Because data in different coordinate systems have specific attributes, the data coordinates in different coordinate systems can be transformed by coordinate mapping. Then the stream data features in a sensor network can be extracted accurately by principal component analysis to improve the detection accuracy of abnormal data points. Clustering of convection data features is implemented to shorten the time of subsequent detection by rapidly classifying data. Finally, the difference point factor is used to detect the nonlinear outliers in the sensor network. Experimental results show that the maximum detection accuracy of this method can reach 97%, the maximum detection time required is only 15s, and the maximum miss rate of this method is 1.32%, indicating that this method can effectively detect nonlinear anomaly points.
  Keywords: Log polar coordinate mapping; Cartesian coordinate system; Principal component analysis; Sensor network; Nonlinear outlier detection.
  
  
• A novel design of the multi-wire based solution for water leak detection and localization in buried pipes  
  by Raouia Khelif, Mohamed Kharrat, Mohamed Abid 
  Abstract: With the increase of the need for freshwater, concerns about leaks in water distribution systems have been increasing. These leaks may cause not only water losses but also significant damages to public property. Proposing an appropriate solution to identify them at an early stage is required to avoid extra problems. This paper presents a novel design of the multi-wire solution for water leak detection and localization in underground pipelines. The enhanced technique aims to overcome the limitations of the old design while preserving the same performance. The novel design uses a reduced number of sensing wires which facilitate the implementation phase, reduce energy consumption and lower the system cost. Several experimental trials were made in the laboratory to test the efficiency of the system. The obtained results confirm that the proposed methodology is highly sensitive to small leaks and accurate in locating them without triggering false alarms.
  Keywords: water conservation; leak detection; leak localization; sensors; multi-wire cable sensor; underground pipelines; water distribution system; soil moisture; system testing; sensitivity; accuracy.
  
  
• An Outlier-based Analysis for Behavior and Anomaly Identification on IoT Sensors  
  by Felipe C. Almeida, Adilson Eduardo Guelfi, Anderson A. A. Silva, Norisvaldo Ferraz Junior, Marvin Oliver Schneider, Vagner Luiz Gava, Sergio Takeo Kofuji 
  Abstract: The pervasive nature of WSN-based IoT devices provides benefits for the industry, healthcare, and other environments. Because of that, a secure network that identifies sensor measurement errors is essential. However, the sensors are sensitive to changes according to the environment in which they are installed. Therefore, this work proposes an outlier-based analysis for behavior and anomaly identification on IoT sensors which is twofold: first, cluster the sensors based on the variance of the devices' sensors; next, identify anomalies applying Mahalanobis distance within the clusters to identify anomalous devices. We use different datasets in the experimental process to validate our proposal. As a result, we demonstrate anomalous sensors identification without relying only on the neighbor measurements (which could lead to incorrect identification of anomalies), and by segregating the sensors' behavior based on day time.
  Keywords: IoT Sensor; Statistical Outliers; Clustering k-means; Mahalanobis Distance; Anomaly identification.