Sensors, Vol. 24, Pages 2545: Pupil Response in Visual Tracking Tasks: The Impacts of Task Load, Familiarity, and Gaze Position
This study explored the effects of task load, task familiarity, and gaze position on pupil response during learning a visual tracking task. We hypothesized that pupil size would increase with task load, up to a certain level before decreasing, decrease with task familiarity, and increase more when focusing on areas preceding the target than other areas. Fifteen participants were recruited for an arrow tracking learning task with incremental task load. Pupil size data were collected using a Tobii Pro Nano eye tracker. A 2 × 3 × 5 three-way factorial repeated measures ANOVA was conducted using R (...
Source: Sensors - April 16, 2024 Category: Biotechnology Authors: Yun Wu Zhongshi Zhang Yao Zhang Bin Zheng Farzad Aghazadeh Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2541: Harmonic FMCW Radar System: Passive Tag Detection and Precise Ranging Estimation
Khaliel
This paper details the design and implementation of a harmonic frequency-modulated continuous-wave (FMCW) radar system, specialized in detecting harmonic tags and achieving precise range estimation. Operating within the 2.4–2.5GHz frequency range for the forward channel and 4.8–5.0GHz for the backward channel, this study delves into the various challenges faced during the system’s realization. These challenges include selecting appropriate components, calibrating the system, processing signals, and integrating the system components. In addition, we introduce a single-la...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Ahmed El-Awamry Feng Zheng Thomas Kaiser Maher Khaliel Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2522: Mind the Exit Pupil Gap: Revisiting the Intrinsics of a Standard Plenoptic Camera
Koch
Among the common applications of plenoptic cameras are depth reconstruction and post-shot refocusing. These require a calibration relating the camera-side light field to that of the scene. Numerous methods with this goal have been developed based on thin lens models for the plenoptic camera’s main lens and microlenses. Our work addresses the often-overlooked role of the main lens exit pupil in these models, specifically in the decoding process of standard plenoptic camera (SPC) images. We formally deduce the connection between the refocusing distance and the resampling parameter for the decoded light...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Tim Michels Daniel M äckelmann Reinhard Koch Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2523: Reconstruction of Radio Environment Map Based on Multi-Source Domain Adaptive of Graph Neural Network for Regression
n Fan
The graph neural network (GNN) has shown outstanding performance in processing unstructured data. However, the downstream task performance of GNN strongly depends on the accuracy of data graph structural features and, as a type of deep learning (DL) model, the size of the training dataset is equally crucial to its performance. This paper is based on graph neural networks to predict and complete the target radio environment map (REM) through multiple complete REMs and sparse spectrum monitoring data in the target domain. Due to the complexity of radio wave propagation in space, it is difficult to accurately and ex...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Xiaomin Wen Shengliang Fang Youchen Fan Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2524: Brake Fluid Condition Monitoring by a Fiber Optic Sensor Using Silica Nanomaterials as Sensing Components
This study addresses this gap by developing a hybrid silica nanofiber mat, or an aerogel integrated with an optical fiber sensor, to monitor brake fluid condition. The incorporation of silica nanofibers in this hybrid enhances the sensitivity of the optical fiber glass surface by at least 3.75 times. Furthermore, creating an air gap between the glass surface of the optical fiber and the nanofibers boosts sensitivity by at least 5 times, achieving a better correlation coefficient (R2 = 0.98). In the case of silica aerogel, the sensitivity is enhanced by 10 times, but this enhancement relies on the presence of the establishe...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Mayza Ibrahim Stanislav Petr ík Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2526: Design of a Self-Measuring Device Based on Bioelectrical Impedance Analysis for Regular Monitoring of Rheumatoid Arthritis
This study underscores the significance of considering patients’ disease activity during intervals between hospital visits and introduces a novel approach to self-RA care. (Source: Sensors)
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: JuYoung Jeong Yun Soo Park Eunchae Lee SeoYoun Choi Dokshin Lim Jiho Kim Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2525: Inspection Robot Navigation Based on Improved TD3 Algorithm
i Yan
The swift advancements in robotics have rendered navigation an essential task for mobile robots. While map-based navigation methods depend on global environmental maps for decision-making, their efficacy in unfamiliar or dynamic settings falls short. Current deep reinforcement learning navigation strategies can navigate successfully without pre-existing map data, yet they grapple with issues like inefficient training, slow convergence, and infrequent rewards. To tackle these challenges, this study introduces an improved two-delay depth deterministic policy gradient algorithm (LP-TD3) for local planning navigation...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Bo Huang Jiacheng Xie Jiawei Yan Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2527: Ballistocardial Signal-Based Personal Identification Using Deep Learning for the Non-Invasive and Non-Restrictive Monitoring of Vital Signs
eno
Owing to accelerated societal aging, the prevalence of elderly individuals experiencing solitary or sudden death at home has increased. Therefore, herein, we aimed to develop a monitoring system that utilizes piezoelectric sensors for the non-invasive and non-restrictive monitoring of vital signs, including the heart rate and respiration, to detect changes in the health status of several elderly individuals. A ballistocardiogram with a piezoelectric sensor was tested using seven individuals. The frequency spectra of the biosignals acquired from the piezoelectric sensors exhibited multiple peaks corresponding to the...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Karin Takahashi Hitoshi Ueno Tags: Communication Source Type: research
Sensors, Vol. 24, Pages 2528: Optimal Design and Development of Magnetic Field Detection Sensor for AC Power Cable
Jingang Su
The state detection of power cables is very important to ensure the reliability of the power supply. Traditional sensors are mostly based on electric field detection. The operation is complex, and its efficiency needs to be improved. This paper optimizes the design and development of the magnetic field detection sensor for AC power cables. First, through the establishment of the magnetic field sensor model, it is determined that permalloy is the material of the magnetic core, the optimal aspect ratio of the magnetic core is 20, and the ratio of coil length to core length is 0.3. Second, the coil-simulation ...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Yong Liu Yuepeng Xin Youcong Huang Boxue Du Xingwang Huang Jingang Su Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2529: Sensor Head Temperature Distribution Reconstruction of High-Precision Gravitational Reference Sensors with Machine Learning
In this study, we utilized XGBoost-LSTM for sensor head temperature reconstruction, and we analyzed the performance of this method under two simulation scenarios: ground-based and on-orbit. The findings demonstrate that our method achieves a precision that is two orders of magnitude higher than that of conventional interpolation methods and one order of magnitude higher than that of a BP neural network. Additionally, it exhibits remarkable stability and robustness. The reconstruction accuracy of this method meets the requirements for the key payload temperature control precision specified by the Taiji Program, providing da...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Zongchao Duan Feilong Ren Li-E Qiang Keqi Qi Haoyue Zhang Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2531: An Intelligent Thermal Compensation System Using Edge Computing for Machine Tools
This study uses time-series thermal compensation to develop a predictive system for thermal displacement in machine tools, which is applicable in the industry using edge computing technology. Two experiments were carried out to optimize the temperature prediction models and predict the displacement of five axes at the temperature points. First, an examination is conducted to determine possible variances in time-series data. This analysis is based on the data obtained for the changes in time, speed, torque, and temperature at various locations of the machine tool. Using the viable machine-learning models determined, the stu...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Endah Kristiani Lu-Yan Wang Jung-Chun Liu Cheng-Kai Huang Shih-Jie Wei Chao-Tung Yang Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2532: On a Closer Look of a Doppler Tolerant Noise Radar Waveform in Surveillance Applications
nário
The prevalence of Low Probability of Interception (LPI) and Low Probability of Exploitation (LPE) radars in contemporary Electronic Warfare (EW) presents an ongoing challenge to defense mechanisms, compelling constant advances in protective strategies. Noise radars are examples of LPI and LPE systems that gained substantial prominence in the past decade despite exhibiting a common drawback of limited Doppler tolerance. The Advanced Pulse Compression Noise (APCN) waveform is a stochastic radar signal proposed to amalgamate the LPI and LPE attributes of a random waveform with the Doppler tolerance feature inherent...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Maximiliano Barbosa Leandro Pralon Antonio L. L. Ramos Jos é Antonio Apolinário Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2530: Human Activity Recognition Based on Deep Learning and Micro-Doppler Radar Data
This study proposes a human activity recognition (HAR) system based on activity data obtained via the micro-Doppler effect, combining a two-stream one-dimensional convolutional neural network (1D-CNN) with a bidirectional gated recurrent unit (BiGRU). Initially, radar sensor data are used to generate information related to time and frequency responses using short-time Fourier transform (STFT). Subsequently, the magnitudes and phase values are calculated and fed into the 1D-CNN and Bi-GRU models to extract spatial and temporal features for subsequent model training and activity recognition. Additionally, we propose a simple...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Tan-Hsu Tan Jia-Hong Tian Alok Kumar Sharma Shing-Hong Liu Yung-Fa Huang Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2533: Shape Sensing of Cantilever Column Using Hybrid Frenet & ndash;Serret Homogeneous Transformation Matrix Method
Sensors, Vol. 24, Pages 2533: Shape Sensing of Cantilever Column Using Hybrid Frenet–Serret Homogeneous Transformation Matrix Method
Sensors doi: 10.3390/s24082533
Authors:
Peng Zhang
Duanshu Li
Ran An
Patil Devendra
The Frenet–Serret (FS) framework stands as a pivotal tool in shape sensing for various infrastructures. However, this tool suffers from accumulative errors, particularly at inflection points where the normal vector undergoes sign changes. To minimize the error, the traditional FS framework is modified by incorporating the homogeneous matrix transformation (HMT) method for ...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Peng Zhang Duanshu Li Ran An Patil Devendra Tags: Article Source Type: research
Sensors, Vol. 24, Pages 2534: Detecting Leadership Opportunities in Group Discussions Using Off-the-Shelf VR Headsets
Discussions Using Off-the-Shelf VR Headsets
Sensors doi: 10.3390/s24082534
Authors:
Chenghao Gu
Jiadong Chen
Jiayi Zhang
Tianyuan Yang
Zhankun Liu
Shin’ichi Konomi
The absence of some forms of non-verbal communication in virtual reality (VR) can make VR-based group discussions difficult even when a leader is assigned to each group to facilitate discussions. In this paper, we discuss if the sensor data from off-the-shelf VR devices can be used to detect opportunities for facilitating engaging discussions and support leaders in VR-based group discussions. To this end, we focus on the detection of suppress...
Source: Sensors - April 15, 2024 Category: Biotechnology Authors: Chenghao Gu Jiadong Chen Jiayi Zhang Tianyuan Yang Zhankun Liu Shin ’ichi Konomi Tags: Article Source Type: research
