Sensors, Vol. 21, Pages 1574: Pentacyanoammineferrate-Based Non-Enzymatic Electrochemical Biosensing Platform for Selective Uric Acid Measurement
im Choi The electrochemical-based detection of uric acid (UA) is widely used for diagnostic purposes. However, various interfering species such as ascorbic acid, dopamine, and glucose can affect electrochemical signals, and hence there is an outstanding need to develop improved sensing platforms to detect UA with high selectivity. Herein, we report a pentagonal mediator-based non-enzymatic electrochemical biosensing platform to selectively measure UA in the presence of interfering species. The working electrode was fabricated by electrodepositing polymerized 1-vinylimidazole (PVI), which has an imidazole ligand, ont...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Jeon Lee Sut Kim Choi Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1575: Decoding of Ankle Joint Movements in Stroke Patients Using Surface Electromyography
In this study, we explored the potential use of surface electromyography (sEMG) as a controlling mechanism for the development of a home-based lower limb rehabilitative device for stroke patients. In this experiment, three channels of sEMG were used to record data from 11 stroke patients while performing ankle joint movements. The movements were then decoded from the sEMG data and their correlation with the level of motor impairment was investigated. The impairment level was quantified using the Fugl-Meyer Assessment (FMA) scale. During the analysis, Hudgins time-domain features were extracted and classified using linear d...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Noor Waris Gilani Kashif Jochumsen Iqbal Niazi Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1576: Review of Wearable Sensor-Based Health Monitoring Glove Devices for Rheumatoid Arthritis
Curran Early detection of Rheumatoid Arthritis (RA) and other neurological conditions is vital for effective treatment. Existing methods of detecting RA rely on observation, questionnaires, and physical measurement, each with their own weaknesses. Pharmaceutical medications and procedures aim to reduce the debilitating effect, preventing the progression of the illness and bringing the condition into remission. There is still a great deal of ambiguity around patient diagnosis, as the difficulty of measurement has reduced the importance that joint stiffness plays as an RA identifier. The research areas of medical reh...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Henderson Condell Connolly Kelly Curran Tags: Review Source Type: research

Sensors, Vol. 21, Pages 1577: Automatic Modulation Recognition Based on a DCN-BiLSTM Network
Huang Automatic modulation recognition (AMR) is a significant technology in noncooperative wireless communication systems. This paper proposes a deep complex network that cascades the bidirectional long short-term memory network (DCN-BiLSTM) for AMR. In view of the fact that the convolution operation of the traditional convolutional neural network (CNN) loses the partial phase information of the modulated signal, resulting in low recognition accuracy, we first apply a deep complex network (DCN) to extract the features of the modulated signal containing phase and amplitude information. Then, we cascade bidirectional lon...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Kai Liu Wanjun Gao Qinghua Huang Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1578: Textile Electrodes: Influence of Knitting Construction and Pressure on the Contact Impedance
ersson Textile electrodes, also called textrodes, for biosignal monitoring as well as electrostimulation are central for the emerging research field of smart textiles. However, so far, only the general suitability of textrodes for those areas was investigated, while the influencing parameters on the contact impedance related to the electrode construction and external factors remain rather unknown. Therefore, in this work, six different knitted electrodes, applied both wet and dry, were compared regarding the influence of specific knitting construction parameters on the three-electrode contact impedance measured on a hu...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Euler Guo Persson Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1579: Multi-Path and Group-Loss-Based Network for Speech Emotion Recognition in Multi-Domain Datasets
This study proposes a multi-path and group-loss-based network (MPGLN) for SER to support multi-domain adaptation. The proposed model includes a bidirectional long short-term memory-based temporal feature generator and a transferred feature extractor from the pre-trained VGG-like audio classification model (VGGish), and it learns simultaneously based on multiple losses according to the association of emotion labels in the discrete and dimensional models. For the evaluation of the MPGLN SER as applied to multi-cultural domain datasets, the Korean Emotional Speech Database (KESD), including KESDy18 and KESDy19, is constructed...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Noh Jeong Lim Chung Kim Lim Jeong Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1580: Thermal Ablation and High-Resolution Imaging Using a Back-to-Back (BTB) Dual-Mode Ultrasonic Transducer: In Vivo Results
In this study, we developed a dual-element transducer composed of two elements that share the same housing but work independently with a BTB structure, enabling a mode change between therapy and imaging via 180-degree mechanical rotation. The optic fibers were embedded in the HIFU focal region of ex vivo chicken breasts and the temperature change was measured. Images were obtained in vivo mice before and after treatment and compared to identify the treated region. We successfully acquired B-mode and C-scan images that display the hyperechoic region indicating coagulation necrosis in the HIFU-treated volume up to a depth of...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Lim Kim Kim Park Kim Yoo Heo Baik Park Kim Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1581: An Automatic Concrete Crack-Detection Method Fusing Point Clouds and Images Based on Improved Otsu ’s Algorithm
In this study, we propose an automatic crack-detection method that fuses 3D point clouds and 2D images based on an improved Otsu algorithm, which consists of the following four major procedures. First, a high-precision registration of a depth image projected from 3D point clouds and 2D images is performed. Second, pixel-level image fusion is performed, which fuses the depth and gray information. Third, a rough crack image is obtained from the fusion image using the improved Otsu method. Finally, the connected domain labeling and morphological methods are used to finely extract the cracks. Experimentally, the proposed metho...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Chen Li Huang Cui Liu Sun Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1582: Investigating the Performance of Gesture-Based Input for Mid-Air Text Entry in a Virtual Environment: A Comparison of Hand-Up Versus Hand-Down Postures
This study aimed to investigate the performance of the word-gesture text entry technology with different input postures and VR experiences in the virtual environment. The study revealed that the VR experience (how long or how often using VR) had little effect on input performance. The hand-up posture has a better input performance when using word-gesture text entry technology in a virtual environment. In addition, the study found that the perceived exertion to complete the text input with word-gesture text entry technology was relatively high. Furthermore, the typing accuracy and perceived usability for using the hand-up p...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Wang Wang Chen Wang Yang Jiang He Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1583: An Optimized Framework for Energy-Resource Allocation in A Cloud Environment based on the Whale Optimization Algorithm
Ijaz Son Cloud computing offers the services to access, manipulate and configure data online over the web. The cloud term refers to an internet network which is remotely available and accessible at anytime from anywhere. Cloud computing is undoubtedly an innovation as the investment in the real and physical infrastructure is much greater than the cloud technology investment. The present work addresses the issue of power consumption done by cloud infrastructure. As there is a need for algorithms and techniques that can reduce energy consumption and schedule resource for the effectiveness of servers. Load balancing...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Goyal Bhushan Kumar Rana Bhutta Ijaz Son Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1584: Industrial Energy Assessment Training Effectiveness Evaluation: An Eye-Tracking Study
Jeon It is essential to understand the effectiveness of any training program so it can be improved accordingly. Various studies have applied standard metrics for the evaluation of visual behavior to recognize the areas of interest that attract individuals’ attention as there is a high correlation between attentional behavior and where one is focusing on. However, through reviewing the literature, we believe that studies that applied eye-tracking technologies for training purposes are still limited, especially in the industrial energy assessment training field. In this paper, the effectiveness of industrial ener...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Ghanbari Wang Jeon Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1585: Surface Plasmon Enhanced Fluorescence Temperature Mapping of Aluminum Nanoparticle Heated by Laser
yay Maschmann Partially aggregated Rhodamine 6G (R6G) dye is used as a lights-on temperature sensor to analyze the spatiotemporal heating of aluminum nanoparticles (Al NPs) embedded within a tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride (THV) fluoropolymer matrix. The embedded Al NPs were photothermally heated using an IR laser, and the fluorescent intensity of the embedded dye was monitored in real time using an optical microscope. A plasmonic grating substrate enhanced the florescence intensity of the dye while increasing the optical resolution and heating rate of Al NPs. The fluorescence inten...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Zakiyyan Darr Chen Mathai Gangopadhyay McFarland Gangopadhyay Maschmann Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1586: Near-Infrared Spectroscopy (NIRS) in Traumatic Brain Injury (TBI)
Kyriacou Traumatic brain injury (TBI) occurs when a sudden trauma causes damage to the brain. TBI can result when the head suddenly and violently impacts an object or when an object pierces the skull and enters brain tissue. Secondary injuries after traumatic brain injury (TBI) can lead to impairments on cerebral oxygenation and autoregulation. Considering that secondary brain injuries often take place within the first hours after the trauma, noninvasive monitoring might be helpful in providing early information on the brain’s condition. Near-infrared spectroscopy (NIRS) is an emerging noninvasive monitoring mod...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Rold án Kyriacou Tags: Review Source Type: research

Sensors, Vol. 21, Pages 1555: Reliability and Validity of Clinically Accessible Smart Glove Technologies to Measure Joint Range of Motion
In conclusion, the ECSMS will benefit in the design of data glove technologies in the future because it provides crucial evidence of sensor characteristics. Similarly, this design greatly enhances the stability and maintainability of sensor assessments by eliminating unwanted errors. These findings provide ample evidence for clinicians to support the use of sensory devices that can calculate joint motion in place of goniometers. (Source: Sensors)
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Jeffrey Henderson Joan Condell James Connolly Daniel Kelly Kevin Curran Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1556: Machine Learning for 5G MIMO Modulation Detection
halid Modulation detection techniques have received much attention in recent years due to their importance in the military and commercial applications, such as software-defined radio and cognitive radios. Most of the existing modulation detection algorithms address the detection dedicated to the non-cooperative systems only. In this work, we propose the detection of modulations in the multi-relay cooperative multiple-input multiple-output (MIMO) systems for 5G communications in the presence of spatially correlated channels and imperfect channel state information (CSI). At the destination node, we extract the higher-ord...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Haithem Ben Chikha Ahmad Almadhor Waqas Khalid Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1557: Investigating the Trackability of Silicon Microprobes in High-Speed Surface Measurements
Uwe Brand High-speed tactile roughness measurements set high demand on the trackability of the stylus probe. Because of the features of low mass, low probing force, and high signal linearity, the piezoresistive silicon microprobe is a hopeful candidate for high-speed roughness measurements. This paper investigates the trackability of these microprobes through building a theoretical dynamic model, measuring their resonant response, and performing tip-flight experiments on surfaces with sharp variations. Two microprobes are investigated and compared: one with an integrated silicon tip and one with a diamond tip glued to ...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Min Xu Zhi Li Michael Fahrbach Erwin Peiner Uwe Brand Tags: Communication Source Type: research

Sensors, Vol. 21, Pages 1558: Sensors for Structural Health Monitoring and Condition Monitoring
Vidal Structural control and health monitoring as condition monitoring [...] (Source: Sensors)
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Francesc Pozo Diego A. Tibaduiza Yolanda Vidal Tags: Editorial Source Type: research

Sensors, Vol. 21, Pages 1559: IoTCrawler: Challenges and Solutions for Searching the Internet of Things
Hien Truong Aurora González-Vidal Antonio F. Skarmeta Parwinder Singh Michail J. Beliatis Mirko Presser Juan A. Martinez Pedro Gonzalez-Gil Marianne Krogbæk Sebastian Holmgård Holmgård Christophersen Due to the rapid development of the Internet of Things (IoT) and consequently, the availability of more and more IoT data sources, mechanisms for searching and integrating IoT data sources become essential to leverage all relevant data for improving processes and services. This paper presents the IoT search framework IoTCrawler. The IoTCrawler framework is not only another IoT fr...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Thorben Iggena Eushay Bin Bin Ilyas Marten Fischer Ralf T önjes Tarek Elsaleh Roonak Rezvani Narges Pourshahrokhi Stefan Bischof Andreas Fernbach Josiane Xavier Xavier Parreira Patrik Schneider Pavel Smirnov Martin Strohbach Hien Truong Aurora Gonz ález Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1560: Resistance Temperature Detectors Fabricated via Dual Fused Deposition Modeling of Polylactic Acid and Polylactic Acid/Carbon Black Composites
e June Kang Planar-type resistance temperature detectors (P-RTDs) were fabricated via fused deposition modeling by dual nozzle extrusion. The temperature-sensing element of the fabricated sensor was printed with electrically conductive polylactic acid/carbon black (PLA/CB) composite, while the structural support was printed with a PLA insulator. The temperature-dependent resistivity change of PLA/CB was evaluated for different stacking sequences of PLA/CB layers printed with [0°/0°], [−45°/45°], and [0°/90°] plies. Compared to a PLA/CB filament used as 3D printing source material, the lami...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Jei Gyeong Jeon Gwang-Wook Hong Hong-Geun Park Sun Kon Lee Joo-Hyung Kim Tae June Kang Tags: Communication Source Type: research

Sensors, Vol. 21, Pages 1561: Classification of Critical Levels of CO Exposure of Firefigthers through Monitored Heart Rate
Ana I. Miranda Smoke inhalation poses a serious health threat to firefighters (FFs), with potential effects including respiratory and cardiac disorders. In this work, environmental and physiological data were collected from FFs, during experimental fires performed in 2015 and 2019. Extending a previous work, which allowed us to conclude that changes in heart rate (HR) were associated with alterations in the inhalation of carbon monoxide (CO), we performed a HR analysis according to different levels of CO exposure during firefighting based on data collected from three FFs. Based on HR collected and on CO occupational...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Raquel Sebasti ão Sandra Sorte Jos é M. Fernandes Ana I. Miranda Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1562: A Systematic Review of Sensing Technologies for Wearable Sleep Staging
z Designing wearable systems for sleep detection and staging is extremely challenging due to the numerous constraints associated with sensing, usability, accuracy, and regulatory requirements. Several researchers have explored the use of signals from a subset of sensors that are used in polysomnography (PSG), whereas others have demonstrated the feasibility of using alternative sensing modalities. In this paper, a systematic review of the different sensing modalities that have been used for wearable sleep staging is presented. Based on a review of 90 papers, 13 different sensing modalities are identified. Each sensing ...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Syed Anas Imtiaz Tags: Review Source Type: research

Sensors, Vol. 21, Pages 1563: RF Transceiver for the Multi-Mode Radar Applications
Cho Young-Jin Kim In this work, a multi-mode radar transceiver supporting pulse, FMCW and CW modes was designed as an integrated circuit. The radars mainly detect the targets move by using the Doppler frequency which is significantly affected by flicker noise of the receiver from several Hz to several kHz. Due to this flicker noise, the long-range detection performance of the radars is greatly reduced, and the accuracy of range to the target and velocity is also deteriorated. Therefore, we propose a transmitter that suppresses LO leakage in consideration of long-range detection, target distance, velocity, and noise f...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Jae Kwon Ha Chang Kyun Noh Jin Seop Lee Ho Jin Kang Yu Min Kim Tae-Hyun Kim Ha-Neul Jung Sang-Hwan Lee Choon Sik Cho Young-Jin Kim Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1565: Enzymatic Activity and Its Relationship with Organic Matter Characterization and Ecotoxicity to Aliivibrio fischeri of Soil Samples Exposed to Tetrabutylphosphonium Bromide
This study aimed to determine the impact of tetrabutylphosphonium bromide [TBP][Br] on the soil environment through an experiment on loamy sand samples. The tested salt was added to soil samples at doses of 0 (control), 1, 10, 100, and 1000 mg kg−1 dry matter (DM). During the experiment, the activity of selected enzymes involved in carbon, phosphorus, and nitrogen cycles, characteristics of organic matter with Fourier-transform infrared (FT-IR) spectroscopy, and toxicity of soil samples in relation to Aliivibrio fischeri were determined at weekly intervals. The results showed that low doses of [TBP][Br] (1 and 10 mg ...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Arkadiusz Telesi ński Barbara Paw łowska Robert Biczak Marek Śnieg Jacek Wr óbel Dorota Dunikowska Edward Meller Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1564: When Measurements Meet Blockchain: On Behalf of an Inter-NMI Network
achado The growing demand for solutions related to measurement (e.g., digital sensors, smart meters, distributed measuring systems) imposes several concerns about information and process reliability. In this context, blockchain can play a crucial role as a platform to implement applications and activities in the context of legal metrology. In most countries, the National Metrology Institutes (NMIs) are responsible for promoting these initiatives. Thus, in this paper, we present a functional architecture to integrate NMIs in a collaborative blockchain network. We discuss the main aspects and features that an inter-NMI b...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Mahbuba Moni Wilson Melo Daniel Peters Raphael Machado Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1566: RS-SSKD: Self-Supervision Equipped with Knowledge Distillation for Few-Shot Remote Sensing Scene Classification
ue Wang While growing instruments generate more and more airborne or satellite images, the bottleneck in remote sensing (RS) scene classification has shifted from data limits toward a lack of ground truth samples. There are still many challenges when we are facing unknown environments, especially those with insufficient training data. Few-shot classification offers a different picture under the umbrella of meta-learning: digging rich knowledge from a few data are possible. In this work, we propose a method named RS-SSKD for few-shot RS scene classification from a perspective of generating powerful representation for th...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Pei Zhang Ying Li Dong Wang Jiyue Wang Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1567: Size- and Time-Dependent Particle Removal Efficiency of Face Masks and Improvised Respiratory Protection Equipment Used during the COVID-19 Pandemic
n;ek Tina Bregant Maja Remškar Size- and time-dependent particle removal efficiency (PRE) of different protective respiratory masks were determined using a standard aerosol powder with the size of particles in the range of an uncoated SARS-CoV-2 virus and small respiratory droplets. Number concentration of particles was measured by a scanning mobility particle sizer. Respiratory protective half-masks, surgical masks, and cotton washable masks were tested. The results show high filtration efficiency of FFP2, FFP3, and certified surgical masks for all sizes of tested particles, while protection efficiency of w...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Anja Poga čnik Krajnc Luka Pirker Ur ška Gradišar Centa Anton Gradi šek Igor B. Mekjavic Matej Godni č Metod Čebašek Tina Bregant Maja Rem škar Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1569: Independent Component Extraction from the Incomplete Coordinate Time Series of Regional GNSS Networks
Wang Independent component analysis (ICA) is one of the most effective approaches in extracting independent signals from a global navigation satellite system (GNSS) regional station network. However, ICA requires the involved time series to be complete, thereby the missing data of incomplete time series should be interpolated beforehand. In this contribution, a modified ICA is proposed, by which the missing data are first recovered based on the reversible property between the original time series and decomposed principal components, then the complete time series are further processed with FastICA. To evaluate the perf...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Tengfei Feng Yunzhong Shen Fengwei Wang Tags: Technical Note Source Type: research

Sensors, Vol. 21, Pages 1568: Efficiently Updating ECG-Based Biometric Authentication Based on Incremental Learning
eolsoo Park Recently, the interest in biometric authentication based on electrocardiograms (ECGs) has increased. Nevertheless, the ECG signal of a person may vary according to factors such as the emotional or physical state, thus hindering authentication. We propose an adaptive ECG-based authentication method that performs incremental learning to identify ECG signals from a subject under a variety of measurement conditions. An incremental support vector machine (SVM) is adopted for authentication implementing incremental learning. We collected ECG signals from 11 subjects during 10 min over six days and used the data f...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Junmo Kim Geunbo Yang Juhyeong Kim Seungmin Lee Ko Keun Kim Cheolsoo Park Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1570: Image Segmentation Using Encoder-Decoder with Deformable Convolutions
anu Image segmentation is an essential step in image analysis that brings meaning to the pixels in the image. Nevertheless, it is also a difficult task due to the lack of a general suited approach to this problem and the use of real-life pictures that can suffer from noise or object obstruction. This paper proposes an architecture for semantic segmentation using a convolutional neural network based on the Xception model, which was previously used for classification. Different experiments were made in order to find the best performances of the model (eg. different resolution and depth of the network and data augmentatio...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Andreea Gurita Irina Georgiana Mocanu Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1571: Human-Robot Perception in Industrial Environments: A Survey
a Sibona Perception capability assumes significant importance for human–robot interaction. The forthcoming industrial environments will require a high level of automation to be flexible and adaptive enough to comply with the increasingly faster and low-cost market demands. Autonomous and collaborative robots able to adapt to varying and dynamic conditions of the environment, including the presence of human beings, will have an ever-greater role in this context. However, if the robot is not aware of the human position and intention, a shared workspace between robots and humans may decrease productivity and lead to...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Andrea Bonci Pangcheng David Cen Cheng Marina Indri Giacomo Nabissi Fiorella Sibona Tags: Review Source Type: research

Sensors, Vol. 21, Pages 1572: A Vibrissa-Inspired Highly Flexible Tactile Sensor: Scanning 3D Object Surfaces Providing Tactile Images
en Behn Just as the sense of touch complements vision in various species, several robots could benefit from advanced tactile sensors, in particular when operating under poor visibility. A prominent tactile sense organ, frequently serving as a natural paragon for developing tactile sensors, is the vibrissae of, e.g., rats. Within this study, we present a vibrissa-inspired sensor concept for 3D object scanning and reconstruction to be exemplarily used in mobile robots. The setup consists of a highly flexible rod attached to a 3D force-torque transducer (measuring device). The scanning process is realized by translational...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Lukas Merker Joachim Steigenberger Rafael Marangoni Carsten Behn Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1573: Experiments of Image Classification Using Dissimilarity Spaces Built with Siamese Networks
Lumini Traditionally, classifiers are trained to predict patterns within a feature space. The image classification system presented here trains classifiers to predict patterns within a vector space by combining the dissimilarity spaces generated by a large set of Siamese Neural Networks (SNNs). A set of centroids from the patterns in the training data sets is calculated with supervised k-means clustering. The centroids are used to generate the dissimilarity space via the Siamese networks. The vector space descriptors are extracted by projecting patterns onto the similarity spaces, and SVMs classify an image by its ...
Source: Sensors - February 24, 2021 Category: Biotechnology Authors: Nanni Minchio Brahnam Maguolo Lumini Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1534: The Optical Signal-to-Crosstalk Ratio for the MBA(N, e, g) Switching Fabric †
Sensors, Vol. 21, Pages 1534: The Optical Signal-to-Crosstalk Ratio for the MBA(N, e, g) Switching Fabric † Sensors doi: 10.3390/s21041534 Authors: Remigiusz Rajewski The banyan-type switching networks, well known in switching theory and called the logdN switching fabrics, are composed of symmetrical switching elements of size d×d. In turn, the modified baseline architecture, called the MBA(N,e,g), is only partially built from symmetrical optical switching elements, and it is constructed mostly from asymmetrical optical switching elements. Recently, it was shown that the MBA(N,e,g) structure requires a...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Remigiusz Rajewski Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1528: Generating Datasets for Anomaly-Based Intrusion Detection Systems in IoT and Industrial IoT Networks
nathan Rodriguez Over the past few years, we have witnessed the emergence of Internet of Things (IoT) and Industrial IoT networks that bring significant benefits to citizens, society, and industry. However, their heterogeneous and resource-constrained nature makes them vulnerable to a wide range of threats. Therefore, there is an urgent need for novel security mechanisms such as accurate and efficient anomaly-based intrusion detection systems (AIDSs) to be developed before these networks reach their full potential. Nevertheless, there is a lack of up-to-date, representative, and well-structured IoT/IIoT-specific datase...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Ismael Essop Jos é C. Ribeiro Maria Papaioannou Georgios Zachos Georgios Mantas Jonathan Rodriguez Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1529: Shape-Based Alignment of the Scanned Objects Concerning Their Asymmetric Aspects
k Racev We introduce an integrated method for processing depth maps measured by a laser profile sensor. It serves for the recognition and alignment of an object given by a single example. Firstly, we look for potential object contours, mainly using the Retinex filter. Then, we select the actual object boundary via shape comparison based on Triangle Area Representation (TAR). We overcome the limitations of the TAR method by extension of its shape descriptor. That is helpful mainly for objects with symmetric shapes but other asymmetric aspects like squares with asymmetric holes. Finally, we use point-to-point pairing, pr...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Andrej Lucny Viliam Dillinger Gabriela Kacurova Marek Racev Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1531: Autonomous Ground Vehicle Lane-Keeping LPV Model-Based Control: Dual-Rate State Estimation and Comparison of Different Real-Time Control Strategies
l Cuenca Masayoshi Tomizuka In this contribution, we suggest two proposals to achieve fast, real-time lane-keeping control for Autonomous Ground Vehicles (AGVs). The goal of lane-keeping is to orient and keep the vehicle within a given reference path using the front wheel steering angle as the control action for a specific longitudinal velocity. While nonlinear models can describe the lateral dynamics of the vehicle in an accurate manner, they might lead to difficulties when computing some control laws such as Model Predictive Control (MPC) in real time. Therefore, our first proposal is to use a Linear Parameter Vary...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Juli án M. Salt Ducajú Juli án J. Salt Llobregat Ángel Cuenca Masayoshi Tomizuka Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1535: The Highly Uniform Photoresponsivity from Visible to Near IR Light in Sb2Te3 Flakes
ei-San Chen Broadband photosensors have been widely studied in various kinds of materials. Experimental results have revealed strong wavelength-dependent photoresponses in all previous reports. This limits the potential application of broadband photosensors. Therefore, finding a wavelength-insensitive photosensor is imperative in this application. Photocurrent measurements were performed in Sb2Te3 flakes at various wavelengths ranging from visible to near IR light. The measured photocurrent change was insensitive to wavelengths from 300 to 1000 nm. The observed wavelength response deviation was lower than that in all p...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Shiu-Ming Huang Jai-Lung Hung Mitch Chou Chi-Yang Chen Fang-Chen Liu Ruei-San Chen Tags: Communication Source Type: research

Sensors, Vol. 21, Pages 1536: A Wearable Navigation Device for Visually Impaired People Based on the Real-Time Semantic Visual SLAM System
ng Arai Wearable auxiliary devices for visually impaired people are highly attractive research topics. Although many proposed wearable navigation devices can assist visually impaired people in obstacle avoidance and navigation, these devices cannot feedback detailed information about the obstacles or help the visually impaired understand the environment. In this paper, we proposed a wearable navigation device for the visually impaired by integrating the semantic visual SLAM (Simultaneous Localization And Mapping) and the newly launched powerful mobile computing platform. This system uses an Image-Depth (RGB-D) camer...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Chen Liu Kojima Huang Arai Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1533: IoT-Based Research Equipment Sharing System for Remotely Controlled Two-Photon Laser Scanning Microscopy
In this study, two-photon laser scanning microscopy (TPLSM) based on the internet of things (IoT) is proposed as a remote research equipment sharing system, which enables the remote sharing economy. IoT modules, where data are transmitted to and received from the remote users in the web service via IoT, instead of a data acquisition (DAQ) system embedded in the conventional TPLSM, are installed in the IoT-based TPLSM (IoT-TPLSM). The performance for each IoT module is evaluated independently, and it is confirmed that it works well even in a personal computer-free environment. In addition, a message queuing telemetry transp...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Eunwoo Park Jaehyun Lim Byung Cheol Park Daekeun Kim Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1537: Development of a Virtual Reality Simulator for an Intelligent Robotic System Used in Ankle Rehabilitation
ordan The traditional systems used in the physiotherapy rehabilitation process are evolving towards more advanced systems that use virtual reality (VR) environments so that the patient in the rehabilitation process can perform various exercises in an interactive way, thus improving the patient’s motivation and reducing the therapist’s work. The paper presents a VR simulator for an intelligent robotic system of physiotherapeutic rehabilitation of the ankle of a person who has had a stroke. This simulator can interact with a real human subject by attaching a sensor that contains a gyroscope and accelerometer ...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Florin Covaciu Adrian Pisla Anca-Elena Iordan Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1538: Implementation of the NHI (Normalized Hot Spot Indices) Algorithm on Infrared ASTER Data: Results and Future Perspectives
In this study, we show the results of this preliminary implementation, achieved investigating the Kilauea (Hawaii, USA), Klyuchevskoy (Kamchatka; Russia), Shishaldin (Alaska; USA), and Telica (Nicaragua) thermal activities of March 2000–2008. We assessed the NHI detections through comparison with the ASTER Volcano Archive (AVA), the manual inspection of satellite imagery, and the information from volcanological reports. Results show that NHI integrated the AVA observations, with a percentage of unique thermal anomaly detections ranging between 8.8% (at Kilauea) and 100% (at Shishaldin). These results demonstrate the ...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Giuseppe Mazzeo Micheal S. Ramsey Francesco Marchese Nicola Genzano Nicola Pergola Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1541: Development and Performance Evaluation of a Bevameter for Measuring Soil Strength
In this study, a new bevameter was developed, and experiments were conducted to clarify the factors that affect the measurement performance of the bevameter. The pressure–sinkage test device was tested with circular plates of different sizes, and the results confirmed that the pressure–sinkage parameters decreased with the plate size. For the shear-test device, normal pressure was applied using a dead load to prevent normal-pressure variation due to displacement and speed. In addition, a spline was installed on top of the shaft connected to the shear ring to measure slip sinkage during the shear test. The resul...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Kim Im Choi Oh Park Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1532: Glacier Geometry Changes in the Western Shore of Admiralty Bay, King George Island over the Last Decades
rzyna Osińska-Skotak This paper presents changes in the range and thickness of glaciers in Antarctic Specially Protected Area (ASPA) No. 128 on King George Island in the period 1956–2015. The research indicates an intensification of the glacial retreat process over the last two decades, with the rate depending on the type of glacier front. In the period 2001–2015, the average recession rate of the ice cliffs of the Ecology Glacier and the northern part of the Baranowski Glacier was estimated to be approximately 15–25 m a−1 and 10–20 m a−1, respectively. Fronts of Sphinx Glacier and ...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Mariusz Pasik Krzysztof Baku ła Sebastian R óżycki Wojciech Ostrowski Maria El żbieta Kowalska Anna Fija łkowska Marcin Rajner S ławomir Łapiński Ireneusz Sobota Marek Kejna Katarzyna Osi ńska-Skotak Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1540: Using Secure Multi-Party Computation to Protect Privacy on a Permissioned Blockchain
nyi Guo The development of information technology has brought great convenience to our lives, but at the same time, the unfairness and privacy issues brought about by traditional centralized systems cannot be ignored. Blockchain is a peer-to-peer and decentralized ledger technology that has the characteristics of transparency, consistency, traceability and fairness, but it reveals private information in some scenarios. Secure multi-party computation (MPC) guarantees enhanced privacy and correctness, so many researchers have been trying to combine secure MPC with blockchain to deal with privacy and trust issues. In this...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Jiapeng Zhou Yuxiang Feng Zhenyu Wang Danyi Guo Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1542: Planar Phase-Variation Microwave Sensors for Material Characterization: A Review and Comparison of Various Approaches
berta Ferran Martín Planar phase-variation microwave sensors have attracted increasing interest in recent years since they combine the advantages of planar technology (including low cost, low profile, and sensor integration with the associated circuitry for post-processing and communication purposes, among others) and the possibility of operation at a single frequency (thereby reducing the costs of the associated electronics). This paper reviews and compares three different strategies for sensitivity improvement in such phase-variation sensors (devoted to material characterization). The considered approaches i...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Jonathan Mu ñoz-Enano Jan Coromina Paris V élez Lijuan Su Marta Gil Pau Casacuberta Ferran Mart ín Tags: Review Source Type: research

Sensors, Vol. 21, Pages 1530: An Investigation on High-Resolution Temperature Measurement in Precision Fly-Cutting
Walter Lang The loads acting on a workpiece during machining processes determine the modification of the surface of the final workpiece and, thus, its functional properties. In this work, a method that uses thermocouples to measure the temperature in precision fly-cutting machining with high spatial and temporal resolution is presented. Experiments were conducted for various materials and machining parameters. We compare experimental measurement data with results from modern and advanced machining process simulation and find a good match between experimental and simulation results. Therefore, the simulation is valid...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Daniel Gr äbner Tjarden Zielinski Andrey Vovk Oltmann Riemer Bernhard Karpuschewski Walter Lang Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1539: Nonlinear Ride Height Control of Active Air Suspension System with Output Constraints and Time-Varying Disturbances
Silvestre This paper addresses the problem of nonlinear height tracking control of an automobile active air suspension with the output state constraints and time-varying disturbances. The proposed control strategy guarantees that the ride height stays within a predefined range, and converges closely to an arbitrarily small neighborhood of the desired height, ensuring uniform ultimate boundedness. The designed nonlinear observer is able to compensate for the time-varying disturbances caused by external random road excitation and perturbations, achieving robust performance. Simulation results obtained from the co-simulat...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Rongchen Zhao Wei Xie Jin Zhao Pak Kin Wong Carlos Silvestre Tags: Letter Source Type: research

Sensors, Vol. 21, Pages 1546: Self-Powered Wireless Sensor Using a Pressure Fluctuation Energy Harvester
We present a subsystem analysis and a full system implementation that considers hydraulic systems with pressure fluctuation amplitudes of less than 1 bar and frequencies of less than 300 Hz. The study examines the frequency response of the energy harvester, the performance of the interface circuit, and the advantages of using an active power improvement unit adapted for piezoelectric stacks. We show that the interface circuit used improves the performance of the energy harvester compared to previous similar studies, showing more power generation compared to the standard interface. Experimental measurements show that the se...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Jesus Javier Aranda Sebastian Bader Bengt Oelmann Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1544: Invariant Image Representation Using Novel Fractional-Order Polar Harmonic Fourier Moments
Qixian Hao Continuous orthogonal moments, for which continuous functions are used as kernel functions, are invariant to rotation and scaling, and they have been greatly developed over the recent years. Among continuous orthogonal moments, polar harmonic Fourier moments (PHFMs) have superior performance and strong image description ability. In order to improve the performance of PHFMs in noise resistance and image reconstruction, PHFMs, which can only take integer numbers, are extended to fractional-order polar harmonic Fourier moments (FrPHFMs) in this paper. Firstly, the radial polynomials of integer-order PHFMs are ...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Chunpeng Wang Hongling Gao Meihong Yang Jian Li Bin Ma Qixian Hao Tags: Article Source Type: research

Sensors, Vol. 21, Pages 1545: Diurnal Physical Activity Patterns across Ages in a Large UK Based Cohort: The UK Biobank Study
eroux The ability of individuals to engage in physical activity is a critical component of overall health and quality of life. However, there is a natural decline in physical activity associated with the aging process. Establishing normative trends of physical activity in aging populations is essential to developing public health guidelines and informing clinical perspectives regarding individuals’ levels of physical activity. Beyond overall quantity of physical activity, patterns regarding the timing of activity provide additional insights into latent health status. Wearable accelerometers, paired with statistic...
Source: Sensors - February 23, 2021 Category: Biotechnology Authors: Julia Wrobel John Muschelli Andrew Leroux Tags: Article Source Type: research