Sensors, Vol. 20, Pages 3821: A Modified Bayesian Framework for Multi-Sensor Target Tracking with Out-of-Sequence-Measurements
Raheel Nawaz Target detection and tracking is important in military as well as in civilian applications. In order to detect and track high-speed incoming threats, modern surveillance systems are equipped with multiple sensors to overcome the limitations of single-sensor based tracking systems. This research proposes the use of information from RADAR and Infrared sensors (IR) for tracking and estimating target state dynamics. A new technique is developed for information fusion of the two sensors in a way that enhances performance of the data association algorithm. The measurement acquisition and processing time of th...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Yifang Shi Sundas Qayyum Sufyan Ali Memon Uzair Khan Junaid Imtiaz Ihsan Ullah Darren Dancey Raheel Nawaz Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3822: Mechanical Properties of Treadmill Surfaces Compared to Other Overground Sport Surfaces
e Garcia-Unanue The mechanical properties of the surfaces used for exercising can affect sports performance and injury risk. However, the mechanical properties of treadmill surfaces remain largely unknown. The aim of this study was, therefore, to assess the shock absorption (SA), vertical deformation (VD) and energy restitution (ER) of different treadmill models and to compare them with those of other sport surfaces. A total of 77 treadmills, 30 artificial turf pitches and 30 athletics tracks were assessed using an advanced artificial athlete device. Differences in the mechanical properties between the surfaces and tre...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Enrique Colino Jose Luis Felipe Bas Van Hooren Leonor Gallardo Kenneth Meijer Alejandro Lucia Jorge Lopez-Fernandez Jorge Garcia-Unanue Tags: Letter Source Type: research

Sensors, Vol. 20, Pages 3823: A Raster-Based Methodology to Detect Cross-Scale Changes in Water Body Representations Caused by Map Generalization
Ai In traditional change detection methods, remote sensing images are the primary raster data for change detection, and the changes produced from cartography generalization in multi-scale maps are not considered. The aim of this research was to use a new kind of raster data, named map tile data, to detect the change information of a multi-scale water system. From the perspective of spatial cognition, a hierarchical system is proposed to detect water area changes in multi-scale tile maps. The detection level of multi-scale water changes is divided into three layers: the body layer, the piece layer, and the slice layer....
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Yilang Shen Tinghua Ai Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3825: A Wearable Device Based on a Fiber Bragg Grating Sensor for Low Back Movements Monitoring
In this study, a novel wearable device embedding a Fiber Bragg Grating sensor for the detection of lumbar flexion-extensions (F/E) in seated subjects is proposed. At first, the manufacturing process of the sensing element was shown together with its mechanical characterization, that shows linear response to strain with a high correlation coefficient (R2 > 0.99) and a sensitivity value (Sε) of 0.20 nm∙mε−1. Then, the capability of the wearable device in measuring F/E in the sagittal body plane was experimentally assessed on a small population of volunteers, using a ...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Martina Zaltieri Carlo Massaroni Daniela Lo Presti Marco Bravi Riccardo Sabbadini Sandra Miccinilli Silvia Sterzi Domenico Formica Emiliano Schena Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3824: Fast AHRS Filter for Accelerometer, Magnetometer, and Gyroscope Combination with Separated Sensor Corrections
;dl Aleš Hamáček A new predictor–corrector filter for attitude and heading reference systems (AHRS) using data from an orthogonal sensor combination of three accelerometers, three magnetometers and three gyroscopes is proposed. The filter uses the predictor—corrector structure, with prediction based on gyroscopes and independent correction steps for acceleration and magnetic field sensors. We propose two variants of the filter: (i) one using mathematical operations of special orthogonal group SO(3), that are accurate for nonlinear operations, for highest possible accuracy, a...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Josef Justa V áclav Šmídl Ale š Hamáček Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3826: A Spatial Group-Based Multi-User Full-Duplex OFDMA MAC Protocol for the Next-Generation WLAN
ao Yang The Wireless Local Area Network (WLAN) has become a dominant piece of technology to carry wireless traffic for Internet of Things (IoT). The next-generation high-density WLAN scenario is very suitable for the development trend of the industrial wireless sensor network. However, in the high-density deployed WLAN scenarios, the access efficiency is low due to severe collisions, and the interference is diffused due to the scattered locations of the parallel access stations (STAs), which results in low area throughput, i.e., low spatial reuse gain. A spatial group-based multi-user full-duplex orthogonal frequency d...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Meiping Peng Bo Li Zhongjiang Yan Mao Yang Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3827: Editorial: Special Issue “Emerging Sensor Technology in Agriculture”
Sensors, Vol. 20, Pages 3827: Editorial: Special Issue “Emerging Sensor Technology in Agriculture” Sensors doi: 10.3390/s20143827 Authors: Carlos Poblete-Echeverría Sigfredo Fuentes Research and innovation activities in the area of sensor technology can accelerate the adoption of new and emerging digital tools in the agricultural sector by the implementation of precision farming practices such as remote sensing, operations, and real-time monitoring [...] (Source: Sensors)
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Carlos Poblete-Echeverr ía Sigfredo Fuentes Tags: Editorial Source Type: research

Sensors, Vol. 20, Pages 3828: Performance Evaluations of LoRa Wireless Communication in Building Environments
Wang The Internet of things presents tremendous opportunities for the energy management and occupant comfort improvement in smart buildings by making data of environmental and equipment parameters more readily and continuously available. Long-range (LoRa) technology provides a comprehensive wireless solution for data acquisition and communication in smart buildings through its superior performance, such as the long-range transmission, low power consumption and strong penetration. Starting with two vital indicators (network transmission delay and packet loss rate), this study explored the coverage and transmission perf...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Ruobing Liang Liang Zhao Peng Wang Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3831: Hydrogen Sensor: Detecting Far-Field Scattering of Nano-Blocks (Mg, Ag, and Pd)
ng Kwon Hydrogen sensor technologies have been rapidly developing. For effective and safe sensing, we proposed a hydrogen sensor composed of magnesium (Mg), silver (Ag), and palladium (Pd) nano-blocks that overcomes the spectral resolution limit. This sensor exploited the properties of Mg and Pd when absorbing hydrogen. Mg became a dielectric material, and the atomic lattice of Pd expanded. These properties led to changes in the plasmonic gap mode between the nano-blocks. Owing to the changing gap mode, the far-field scattering pattern significantly changed with the hydrogen concentration. Thus, sensing the hydrogen co...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Eunso Shin Young Jin Lee Hyoungjoo Nam Soon-Hong Kwon Tags: Letter Source Type: research

Sensors, Vol. 20, Pages 3830: Advanced Computation Capacity Modeling for Delay-Constrained Placement of IoT Services
lázs Sonkoly A vast range of sensors gather data about our environment, industries and homes. The great profit hidden in this data can only be exploited if it is integrated with relevant services for analysis and usage. A core concept of the Internet of Things targets this business opportunity through various applications. The virtualized and software-controlled 5G networks are expected to achieve the scale and dynamicity of communication networks required by Internet of Things (IoT). As the computation and communication infrastructure rapidly evolves, the corresponding substrate models of service placement algo...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: Bal ázs Németh Bal ázs Sonkoly Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3832: SVM+KF Target Tracking Strategy Using the Signal Strength in Wireless Sensor Networks
Li Wu Target Tracking (TT) (DBSCNA: density-based spatial clustering of application with noise; DPF: distributed particle filter; ELM: extreme learning machine; EKF: extended Kalman filter (KF); GRNN: generalized regression neural network; KF: Kalman filter; LBE: learning-by-example; MLE: maximum likelihood estimator; NN: neural network; PF: particle filter; RSSI: received signal strength indication; RR: ridge regression; RMSE: root-mean-square-error; SVM: support vector machine; TT: target tracking; UKF: unscented KF; WSNs: wireless sensor networks) is a fundamental application of wireless sensor networks. TT base...
Source: Sensors - July 9, 2020 Category: Biotechnology Authors: SVMKF Target Tracking Strategy Using the Signal Strength in Wireless Sensor Wang Liu Wang Li Wu Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3808: A Comparative and Review Study on Shape and Stress Sensing of Flat/Curved Shell Geometries Using C0-Continuous Family of iFEM Elements
In this study, we methodologically compare and review the accuracy and performance of C0-continuous flat and curved inverse-shell elements (i.e., iMIN3, iQS4, and iCS8) for inverse finite element method (iFEM) in terms of shape, strain, and stress monitoring, and damage detection on various plane and curved geometries subjected to different loading and constraint conditions. For this purpose, four different benchmark problems are proposed, namely, a tapered plate, a quarter of a cylindrical shell, a stiffened curved plate, and a curved plate with a degraded material region in stiffness, representing a damage. The complexit...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Mohammad Amin Abdollahzadeh Adnan Kefal Mehmet Yildiz Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3809: Impedance Enhancement of Textile Grounded Loop Antenna Using High-Impedance Surface (HIS) for Healthcare Applications
mainy In this paper, impedance matching enhancement of a grounded wearable low-profile loop antenna is investigated using a high-impedance surface (HIS) structure. The wearable loop antenna along with the HIS structure is maintained low-profile, making it a suitable candidate for healthcare applications. The paper starts with investigating, both numerically and experimentally, the effects of several textile parameters on the performance of the wearable loop antenna. The application of impedance enhancement of wearable grounded loop antenna with HIS structure is then demonstrated. Numerical full-wave simulations are pre...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Mohammed M. Bait-Suwailam Isidoro I. Labiano Akram Alomainy Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3810: The Gaitprint: Identifying Individuals by Their Running Style
ten Recognizing the characteristics of a well-developed running style is a central issue in athletic sub-disciplines. The development of portable micro-electro-mechanical-system (MEMS) sensors within the last decades has made it possible to accurately quantify movements. This paper introduces an analysis method, based on limit-cycle attractors, to identify subjects by their specific running style. The movement data of 30 athletes were collected over 20 min. in three running sessions to create an individual gaitprint. A recognition algorithm was applied to identify each single individual as compared to other participant...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Christian Weich Manfred M. Vieten Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3812: Evaluation of the Data Quality from a Round-Robin Test of Hyperspectral Imaging Systems
In this study, the results from a round-robin test of hyperspectral imaging systems are presented and analyzed. Fourteen different pushbroom hyperspectral systems from eight different institutions were used to acquire spectral cubes from the visible, near infra-red and short-wave infra-red regions. Each system was used to acquire a common set of targets under their normal operating conditions with the data calibrated and processed using the standard processing pipeline for each system. The test targets consisted of a spectral wavelength standard and of a custom-made pigment panel featuring Renaissance-era pigments frequent...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Ruven Pillay Marcello Picollo Jon Yngve Hardeberg Sony George Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3813: Antiresonant Hollow-Core Fiber-Based Dual Gas Sensor for Detection of Methane and Carbon Dioxide in the Near- and Mid-Infrared Regions
Jonathan Knight In this work, we present for the first time a laser-based dual gas sensor utilizing a silica-based Antiresonant Hollow-Core Fiber (ARHCF) operating in the Near- and Mid-Infrared spectral region. A 1-m-long fiber with an 84-µm diameter air-core was implemented as a low-volume absorption cell in a sensor configuration utilizing the simple and well-known Wavelength Modulation Spectroscopy (WMS) method. The fiber was filled with a mixture of methane (CH4) and carbon dioxide (CO2), and a simultaneous detection of both gases was demonstrated targeting their transitions at 3.334 µ...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Piotr Jaworski Pawe ł Kozioł Karol Krzempek Dakun Wu Fei Yu Piotr Boj ęś Grzegorz Dudzik Meisong Liao Krzysztof Abramski Jonathan Knight Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3811: A Method for Sensor-Based Activity Recognition in Missing Data Scenario
We examined the method for different missing percentages, varied window sizes, and diverse window sliding widths. Our explorations demonstrated improved recognition performances even in the presence of missing data. The achieved results provide persuasive findings on sensor-based activity recognition in the presence of missing data. (Source: Sensors)
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Tahera Hossain Md. Atiqur Rahman Ahad Sozo Inoue Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3814: Energy Consumption Evaluation of a Routing Protocol for Low-Power and Lossy Networks in Mesh Scenarios for Precision Agriculture
o Silva Sensor nodes are small, low-cost electronic devices that can self-organize into low-power networks and are susceptible to data packet loss, having computational and energy limitations. These devices expand the possibilities in many areas, like agriculture and urban spaces. In this work, we consider an IoT environment for monitoring a coffee plantation in precision agriculture. We investigate the energy consumption under low-power and lossy networks considering three different network topologies and an Internet Engineering Task Force (IETF) standardized Low-power and Lossy Network (LLN) routing protocol, the Rou...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Frederico O. Sales Yelco Marante Alex B. Vieira Edelberto Franco Silva Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3816: A Multi-Level Approach to Waste Object Segmentation
ngyi Ye We address the problem of localizing waste objects from a color image and an optional depth image, which is a key perception component for robotic interaction with such objects. Specifically, our method integrates the intensity and depth information at multiple levels of spatial granularity. Firstly, a scene-level deep network produces an initial coarse segmentation, based on which we select a few potential object regions to zoom in and perform fine segmentation. The results of the above steps are further integrated into a densely connected conditional random field that learns to respect the appearance, depth, ...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Tao Wang Yuanzheng Cai Lingyu Liang Dongyi Ye Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3815: Energy Optimization of the ‘Shore to Ship’ System—A Universal Power System for Ships at Berth in a Port
This article presents an analysis of steady state electromagnetic and energy processes, allowing the determination of the active and reactive power and losses in the STS system. The presented analytical research enables the development of a control algorithm that optimizes the system energy efficiency. In the article, the control methods allowing the optimization of the energy characteristics of the system are considered and investigated. On the basis of theoretical studies, a model was developed in the Matlab-Simulink environment, which allowed us to study steady and transient processes in the STS system in order to reduc...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Sergey German-Galkin Dariusz Tarnapowicz Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3817: Explaining the Attributes of a Deep Learning Based Intrusion Detection System for Industrial Control Networks
ing Liu Intrusion detection is only the initial part of the security system for an industrial control system. Because of the criticality of the industrial control system, professionals still make the most important security decisions. Therefore, a simple intrusion alarm has a very limited role in the security system, and intrusion detection models based on deep learning struggle to provide more information because of the lack of explanation. This limits the application of deep learning methods to industrial control network intrusion detection. We analyzed the deep neural network (DNN) model and the interpretable classi...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Zhidong Wang Yingxu Lai Zenghui Liu Jing Liu Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3818: Encoding Time Series as Multi-Scale Signed Recurrence Plots for Classification Using Fully Convolutional Networks
Ouyang Recent advances in time series classification (TSC) have exploited deep neural networks (DNN) to improve the performance. One promising approach encodes time series as recurrence plot (RP) images for the sake of leveraging the state-of-the-art DNN to achieve accuracy. Such an approach has been shown to achieve impressive results, raising the interest of the community in it. However, it remains unsolved how to handle not only the variability in the distinctive region scale and the length of sequences but also the tendency confusion problem. In this paper, we tackle the problem using Multi-scale Signed Recurrence...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Ye Zhang Yi Hou Shilin Zhou Kewei Ouyang Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3819: VNF Chain Placement for Large Scale IoT of Intelligent Transportation
njia Wang With the advent of the Internet of things (IoT), intelligent transportation has evolved over time to improve traffic safety and efficiency as well as to reduce congestion and environmental pollution. However, there are some challenging issues to be addressed so that it can be implemented to its full potential. The major challenge in intelligent transportation is that vehicles and pedestrians, as the main types of edge nodes in IoT infrastructure, are on the constant move. Hence, the topology of the large scale network is changing rapidly over time and the service chain may need reestablishment frequently. Exi...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Xing Wu Jing Duan Mingyu Zhong Peng Li Jianjia Wang Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3820: Recent Analysis of Forged Request Headers Constituted by HTTP DDoS
Mohd Yusop Application Layer Distributed Denial of Service (DDoS) attacks are very challenging to detect. The shortfall at the application layer allows formation of HTTP DDoS as the request headers are not compulsory to be attached in an HTTP request. Furthermore, the header is editable, thus providing an attacker with the advantage to execute HTTP DDoS as it contains almost similar request header that can emulate a genuine client request. To the best of the authors’ knowledge, there are no recent studies that provide forged request headers pattern with the execution of the current HTTP DDoS attack scrip...
Source: Sensors - July 8, 2020 Category: Biotechnology Authors: Abdul Ghafar Jaafar Saiful Adli Ismail Mohd Shahidan Abdullah Nazri Kama Azri Azmi Othman Mohd Yusop Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3806: Quantized Residual Preference based Linkage Clustering for Model Selection and Inlier Segmentation in Geometric Multi-Model Fitting
Bin Luo In this paper, quantized residual preference is proposed to represent the hypotheses and the points for model selection and inlier segmentation in multi-structure geometric model fitting. First, a quantized residual preference is proposed to represent the hypotheses. Through a weighted similarity measurement and linkage clustering, similar hypotheses are put into one cluster, and hypotheses with good quality are selected from the clusters as the model selection results. After this, the quantized residual preference is also used to present the data points, and through the linkage clustering, the inliers belongin...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Qing Zhao Yun Zhang Qianqing Qin Bin Luo Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3807: Age-Related Differences in Fixation Pattern on a Companion Robot
Ju Recent studies have addressed the various benefits of companion robots and expanded the research scope to their design. However, the viewpoints of older adults have not been deeply investigated. Therefore, this study aimed to examine the distinctive viewpoints of older adults by comparing them with those of younger adults. Thirty-one older and thirty-one younger adults participated in an eye-tracking experiment to investigate their impressions of a bear-like robot mockup. They also completed interviews and surveys to help us understand their viewpoints on the robot design. The gaze behaviors and the impressions of ...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Young Hoon Oh Da Young Ju Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3794: A QoE-Aware Energy Supply Scheme over a FiWi Access Network in the 5G Era
ang Integrated fiber-wireless (FiWi) should be regarded as a promising access network architecture in future 5G networks, and beyond; this due to its seamless combination of flexibility, ubiquity, mobility of the wireless mesh network (WMN) frontend with a large capacity, high bandwidth, strong robustness in time, and a wavelength-division multiplexed passive optical network (TWDM-PON) backhaul. However, the key issue in both traditional human-to-human (H2H) traffic and emerging Tactile Internet is the energy conservation network operation. Therefore, a power-saving method should be instrumental in the wireless retrans...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Chao He Ruyan Wang Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3795: Detecting and Tracking Criminals in the Real World through an IoT-Based System
lhäuser Criminals and related illegal activities represent problems that are neither trivial to predict nor easy to handle once they are identified. The Police Forces (PFs) typically base their strategies solely on their intra-communication, by neglecting the involvement of third parties, such as the citizens, in the investigation chain which results in a lack of timeliness among the occurrence of the criminal event, its identification, and intervention. In this regard, a system based on IoT social devices, for supporting the detection and tracking of criminals in the real world, is proposed. It aims to enable the...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Andrea Tundis Humayun Kaleem Max M ühlhäuser Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3796: 3D Contact Position Estimation of Image-Based Areal Soft Tactile Sensor with Printed Array Markers and Image Sensors
n Young Kim Tactile sensors have been widely used and researched in various fields of medical and industrial applications. Gradually, they will be used as new input devices and contact sensors for interactive robots. If a tactile sensor is to be applied to various forms of human–machine interactions, it needs to be soft to ensure comfort and safety, and it should be easily customizable and inexpensive. The purpose of this study is to estimate 3D contact position of a novel image-based areal soft tactile sensor (IASTS) using printed array markers and multiple cameras. First, we introduce the hardware struc...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Jong-il Lee Suwoong Lee Hyun-Min Oh Bo Ram Cho Kap-Ho Seo Min Young Kim Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3797: Laboratory Testing of FBGs for Pipeline Monitoring
dio The monitoring of the effects of geohazards on pipelines can be addressed by optical fiber Bragg gratings (FBGs). They are sensitive to strain and bending, and are installed on the external surface of pipelines at discrete locations. A joint approach of theoretical analysis and laboratory experiments is useful to check the reliability of the performance of this technology. We focus on the theoretical analysis of pipeline buckling and investigate the reliability of FBG monitoring both by examining the analytical model available and by performing a laboratory-scale experiment. The novelty lies in the analysis of mode...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Andrea Carlino Alberto Godio Tags: Letter Source Type: research

Sensors, Vol. 20, Pages 3799: Feature Point Registration Model of Farmland Surface and Its Application Based on a Monocular Camera
In this study, an image registration algorithm was applied to calculate the rotation angle of objects when matching images. Some commonly used image feature detection algorithms such as features from accelerated segment test (FAST), speeded up robust features (SURF) and maximally stable extremal regions (MSER) algorithms were chosen as feature extraction components. Comparing the running time and accuracy, the image registration algorithm based on SURF has better performance than the other algorithms. Accurately obtaining the roll angle is one of the key technologies to improve the positioning accuracy and operation qualit...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Yang Li Dongyan Huang Jiangtao Qi Sikai Chen Huibin Sun Huili Liu Honglei Jia Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3800: Dynamic Flow-Adaptive Spectrum Leasing with Channel Aggregation in Cognitive Radio Networks
ei Jiao Cognitive radio networks (CRNs), which allow secondary users (SUs) to dynamically access a network without affecting the primary users (PUs), have been widely regarded as an effective approach to mitigate the shortage of spectrum resources and the inefficiency of spectrum utilization. However, the SUs suffer from frequent spectrum handoffs and transmission limitations. In this paper, considering the quality of service (QoS) requirements of PUs and SUs, we propose a novel dynamic flow-adaptive spectrum leasing with channel aggregation. Specifically, we design an adaptive leasing algorithm, which adaptively adjus...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Xiang Xiao Fanzi Zeng Zhenzhen Hu Lei Jiao Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3798: Development of a High Precision Telescopic Instrument Based on Simultaneous Laser Multilateration for Machine Tool Volumetric Verification
e Santolaria This paper presents the design of a high precision telescopic system consisting in three lines, with measuring principle based on simultaneous laser multilateration. The system offers the high precision of the interferometer systems and allows the autonomous tracking of a sphere joined to the spindle nose of the machine tool by simultaneous contact of all the lines. The main advantage of the system is that it allows data capture to be carried out in a single cycle thanks to simultaneous operation with at least three telescopic arms using a novel multipoint kinematic coupling. This results in a significant ...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Juan Jos é Aguilar Raquel Acero Francisco Javier Brosed Jorge Santolaria Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3801: InSAR Signal and Data Processing
We present here the recent advances in exploring new techniques related to interferometric synthetic aperture radar (InSAR) signal and data processing and applications. (Source: Sensors)
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Mengdao Xing Zhong Lu Hanwen Yu Tags: Editorial Source Type: research

Sensors, Vol. 20, Pages 3802: A Maze Matrix-Based Secret Image Sharing Scheme with Cheater Detection
n Chang Secret image sharing is a technique for sharing a secret message in such a fashion that stego image shadows are generated and distributed to individual participants. Without the complete set of shadows shared among all participants, the secret could not be deciphered. This technique may serve as a crucial means for protecting private data in massive Internet of things applications. This can be realized by distributing the stego image shadows to different devices on the Internet so that only the ones who are authorized to access these devices can extract the secret message. In this paper, we proposed a secret im...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Ching-Chun Chang Ji-Hwei Horng Chia-Shou Shih Chin-Chen Chang Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3803: Deep Sensing: Inertial and Ambient Sensing for Activity Context Recognition using Deep Convolutional Neural Networks
Myoung Lee With the widespread use of embedded sensing capabilities of mobile devices, there has been unprecedented development of context-aware solutions. This allows the proliferation of various intelligent applications, such as those for remote health and lifestyle monitoring, intelligent personalized services, etc. However, activity context recognition based on multivariate time series signals obtained from mobile devices in unconstrained conditions is naturally prone to imbalance class problems. This means that recognition models tend to predict classes with the majority number of samples whilst ignoring classes ...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Abayomi Otebolaku Timibloudi Enamamu Ali Alfoudi Augustine Ikpehai Jims Marchang Gyu Myoung Lee Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3804: A Novel Just-in-Time Learning Strategy for Soft Sensing with Improved Similarity Measure Based on Mutual Information and PLS
Ren In modern industrial process control, just-in-time learning (JITL)-based soft sensors have been widely applied. An accurate similarity measure is crucial in JITL-based soft sensor modeling since it is not only the basis for selecting the nearest neighbor samples but also determines sample weights. In recent years, JITL similarity measure methods have been greatly enriched, including methods based on Euclidean distance, weighted Euclidean distance, correlation, etc. However, due to the different influence of input variables on output, the complex nonlinear relationship between input and output, the collinearity betw...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Yueli Song Minglun Ren Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3805: Application of Inertial Motion Unit-Based Kinematics to Assess the Effect of Boot Modifications on Ski Jump Landings –A Methodological Study
In this study, a methodological approach was developed merging 2D video recordings with sensor-based motion capture to investigate ski jump landings. A reference measurement was carried out in a laboratory, and subsequently, the method was exemplified in a field study by assessing the effect of a ski boot modification on landing kinematics. Landings of four expert skiers were filmed under field conditions in the jump plane, and full body kinematics were measured with an inertial motion unit (IMU) -based motion capture suit. This exemplary study revealed that the combination of video and IMU data is viable. However, only on...
Source: Sensors - July 7, 2020 Category: Biotechnology Authors: Nicolas Kurpiers Nicola Petrone Matej Supej Anna Wisser Jakob Hansen Uwe G. Kersting Tags: Letter Source Type: research

Sensors, Vol. 20, Pages 3777: Triaxial Accelerometer-Based Falls and Activities of Daily Life Detection Using Machine Learning
amzan The detection of activities of daily living (ADL) and the detection of falls is of utmost importance for addressing the issue of serious injuries and death as a consequence of elderly people falling. Wearable sensors can provide a viable solution for monitoring people in danger of falls with minimal external involvement from health or care home workers. In this work, we recorded accelerometer data from 35 healthy individuals performing various ADLs, as well as falls. Spatial and frequency domain features were extracted and used for the training of machine learning models with the aim of distinguishing between fal...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Turke Althobaiti Stamos Katsigiannis Naeem Ramzan Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3779: Sensor Modeling and Calibration Method Based on Extinction Ratio Error for Camera-Based Polarization Navigation Sensor
ang Guo The performance of camera-based polarization sensors largely depends on the estimated model parameters obtained through calibration. Limited by manufacturing processes, the low extinction ratio and inconsistency of the polarizer can reduce the measurement accuracy of the sensor. To account for the challenges, one extinction ratio coefficient was introduced into the calibration model to unify the light intensity of two orthogonal channels. Since the introduced extinction ratio coefficient is associated with degree of polarization (DOP), a new calibration method considering both azimuth of polarization (AOP) e...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Ren Yang Liu Huang Guo Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3778: Health Promotion for Childhood Obesity: An Approach Based on Self-Tracking of Data
z-Cruz Francisco García-Peñalvo At present, obesity and overweight are a global health epidemic. Traditional interventions for promoting healthy habits do not appear to be effective. However, emerging technological solutions based on wearables and mobile devices can be useful in promoting healthy habits. These applications generate a considerable amount of tracked activity data. Consequently, our approach is based on the quantified-self model for recommending healthy activities. Gamification can also be used as a mechanism to enhance personalization, increasing user motivation. This paper describes the ...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Nazaret G ómez del Río Carina S. Gonz ález-González Pedro A. Toledo-Delgado Vanesa Mu ñoz-Cruz Francisco Garc ía-Peñalvo Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3780: Improving Object Tracking by Added Noise and Channel Attention
n Ki Jung CNN-based trackers, especially those based on Siamese networks, have recently attracted considerable attention because of their relatively good performance and low computational cost. For many Siamese trackers, learning a generic object model from a large-scale dataset is still a challenging task. In the current study, we introduce input noise as regularization in the training data to improve generalization of the learned model. We propose an Input-Regularized Channel Attentional Siamese (IRCA-Siam) tracker which exhibits improved generalization compared to the current state-of-the-art trackers. In particular...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Mustansar Fiaz Arif Mahmood Ki Yeol Baek Sehar Shahzad Farooq Soon Ki Jung Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3781: Counting Crowds with Perspective Distortion Correction via Adaptive Learning
Jing Yang The goal of crowd counting is to estimate the number of people in the image. Presently, use regression to count people number became a mainstream method. It is worth noting that, with the development of convolutional neural networks (CNN), methods that are based on CNN have become a research hotspot. It is a more interesting topic that how to locate the site of the person in the image than simply predicting the number of people in the image. The perspective transformation present is still a challenge, because perspective distortion will cause differences in the size of the crowd in the image. To devote perspe...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Yixuan Sun Jian Jin Xingjiao Wu Tianlong Ma Jing Yang Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3783: Viewpoint Analysis for Maturity Classification of Sweet Peppers
el Edan The effect of camera viewpoint and fruit orientation on the performance of a sweet pepper maturity level classification algorithm was evaluated. Image datasets of sweet peppers harvested from a commercial greenhouse were collected using two different methods, resulting in 789 RGB—Red Green Blue (images acquired in a photocell) and 417 RGB-D—Red Green Blue-Depth (images acquired by a robotic arm in the laboratory), which are published as part of this paper. Maturity level classification was performed using a random forest algorithm. Classifications of maturity level from different cam...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Ben Harel Rick van Essen Yisrael Parmet Yael Edan Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3782: Architecture for Trajectory-Based Fishing Ship Classification with AIS Data
José Manuel Molina This paper proposes a data preparation process for managing real-world kinematic data and detecting fishing vessels. The solution is a binary classification that classifies ship trajectories into either fishing or non-fishing ships. The data used are characterized by the typical problems found in classic data mining applications using real-world data, such as noise and inconsistencies. The two classes are also clearly unbalanced in the data, a problem which is addressed using algorithms that resample the instances. For classification, a series of features are extracted from spatiotemporal d...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: David S ánchez Pedroche Daniel Amigo Jes ús García Jos é Manuel Molina Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3784: Understanding Smartwatch Battery Utilization in the Wild
za Rawassizadeh Smartwatch battery limitations are one of the biggest hurdles to their acceptability in the consumer market. To our knowledge, despite promising studies analyzing smartwatch battery data, there has been little research that has analyzed the battery usage of a diverse set of smartwatches in a real-world setting. To address this challenge, this paper utilizes a smartwatch dataset collected from 832 real-world users, including different smartwatch brands and geographic locations. First, we employ clustering to identify common patterns of smartwatch battery utilization; second, we introduce a transparent lo...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Morteza Homayounfar Amirhossein Malekijoo Aku Visuri Chelsea Dobbins Ella Peltonen Eugene Pinsky Kia Teymourian Reza Rawassizadeh Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3785: Pupil Localisation and Eye Centre Estimation Using Machine Learning and Computer Vision
l-askar Various methods have been used to estimate the pupil location within an image or a real-time video frame in many fields. However, these methods lack the performance specifically in low-resolution images and varying background conditions. We propose a coarse-to-fine pupil localisation method using a composite of machine learning and image processing algorithms. First, a pre-trained model is employed for the facial landmark identification to extract the desired eye frames within the input image. Then, we use multi-stage convolution to find the optimal horizontal and vertical coordinates of the pupil within the id...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Wasiq Khan Abir Hussain Kaya Kuru Haya Al-askar Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3786: Practical Judgment of Workload Based on Physical Activity, Work Conditions, and Worker ’s Age in Construction Site
This study aims to develop a practical judgement method to estimate the workload risk of individual construction workers. Based on studies, we developed a workload model comprising a hygrothermal environment, behavioral information, and the physical characteristics of workers). The construction workers’ heart rate and physical activity were measured using the data collected from a wearable device equipped with a biosensor and an acceleration sensor. This study is the first report to use worker physical activity, age, and the wet bulb globe temperature (WBGT) to determine a worker’s physical work...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Nobuki Hashiguchi Kota Kodama Yeongjoo Lim Chang Che Shinichi Kuroishi Yasuhiro Miyazaki Taizo Kobayashi Shigeo Kitahara Kazuyoshi Tateyama Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3787: Foot-Mounted Pedestrian Navigation Method by Comparing ADR and Modified ZUPT Based on MEMS IMU Array
Chen Using an MEMS Inertial Measurement Unit (MEMS IMU) array mounted on foot is a feasible approach to improve the pedestrian tracking accuracy for the pedestrian navigation system (PNS). Based on the in-house developed IMU array, the paper proposes a new integrated framework that combines adaptive deck reckoning (ADR) with the modified zero velocity update (ZUPT). In the proposed ADR algorithm, the IMUs with large drift errors on the array are selected and removed according to the step length and the track angle computed by each IMU on the array. Then, by using the step length and the track angle of each step comput...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Li Xing Xiaowei Tu Zhi Chen Tags: Article Source Type: research

Sensors, Vol. 20, Pages 3788: ACE: ARIA-CTR Encryption for Low-End Embedded Processors
on Park In this paper, we present the first optimized implementation of ARIA block cipher on low-end 8-bit Alf and Vegard’s RISC processor (AVR) microcontrollers. To achieve high-speed implementation, primitive operations, including rotation operation, a substitute layer, and a diffusion layer, are carefully optimized for the target low-end embedded processor. The proposed ARIA implementation supports the electronic codebook (ECB) and the counter (CTR) modes of operation. In particular, the CTR mode of operation is further optimized with the pre-computed table of two add-round-key, one substitute layer, a...
Source: Sensors - July 6, 2020 Category: Biotechnology Authors: Hwajeong Seo Hyeokdong Kwon Hyunji Kim Jaehoon Park Tags: Article Source Type: research