Not only are wearable sensor devices vulnerable to cyber security attacks, but also physical threats when left unattended. However, existing approaches are not well-suited for resource-constrained wearable sensor devices, leading to substantial communication and computational burdens, and hampering the efficient simultaneous verification of multiple devices. Accordingly, an authentication and group-proof system incorporating physical unclonable functions (PUFs) for wearable computing, labeled as AGPS-PUFs, was created, resulting in superior security and cost-effectiveness compared to previous solutions. Utilizing the ROR Oracle model and AVISPA, a formal security analysis evaluated the AGPS-PUF's security posture. Our testbed experiments, leveraging MIRACL on Raspberry Pi 4, were followed by a comparative performance assessment of the AGPS-PUF scheme in relation to previous schemes. Therefore, the AGPS-PUF outperforms existing schemes in terms of security and efficiency, and its application in practical wearable computing environments is viable.
A proposed distributed temperature sensing method that incorporates Rayleigh backscattering-enhanced fiber (RBEF) as the sensing element, leveraging OFDR, is outlined. Randomly distributed high backscattering points are a hallmark of the RBEF; the sliding cross-correlation procedure quantifies the shift in fiber position for these points following temperature variation along the fiber's path, both before and after. The fiber's position and temperature variations are accurately demodulated through the calibration of a mathematical relationship that correlates the high backscattering point position along the RBEF with the temperature change. Experimental observations indicate a direct linear relationship between temperature variations and the total positional change of points exhibiting high backscattering. The temperature sensing sensitivity for the fiber segment, impacted by temperature, is 7814 m/(mC), showing an average relative error in temperature measurement of -112% and a minimal positioning error of 0.002 meters. The spatial resolution of the temperature sensor, as determined by the proposed demodulation method, is governed by the distribution of locations exhibiting high backscattering. The length of the temperature-affected fiber and the spatial resolution of the OFDR system jointly influence the accuracy of temperature measurement. With a 125-meter spatial resolution, the OFDR system provides a temperature sensing accuracy of 0.418°C per meter of the examined RBEF.
The ultrasonic welding system's ultrasonic power supply, by driving the piezoelectric transducer into resonance, brings about the conversion of electrical energy to mechanical energy. To guarantee welding quality and achieve consistent ultrasonic energy, this paper develops a driving power supply incorporating a dual-function LC matching network, which includes frequency tracking and power regulation. To analyze the dynamic behavior of the piezoelectric transducer, we propose a refined LC matching network, employing three RMS voltage values to determine the dynamic branch and pinpoint the series resonant frequency. The driving power system's architecture is additionally based on employing the three RMS voltage values as feedback mechanisms. A fuzzy control system is applied to the task of frequency tracking. Power regulation is achieved by the double closed-loop control method, with an exterior power loop and an interior current loop. M4205 Using MATLAB's modeling capabilities and physical experimentation, the power supply's capacity for precisely tracking the series resonant frequency and offering continuously adjustable power is established. Ultrasonic welding techniques show promise, thanks to this study, for tackling complex load scenarios.
Planar fiducial markers are a common approach for determining the pose of a camera relative to the marker's coordinates. The system's global or local positioning within its environment can be precisely determined using this data in conjunction with other sensor measurements through a state estimator, exemplified by the Kalman filter. For accurate estimation, the observation noise covariance matrix's configuration should accurately portray the sensor's performance characteristics. Salmonella infection Pose estimations derived from planar fiducial markers are affected by varying noise levels across different measurement ranges. This non-uniformity demands consideration during sensor fusion to achieve a reliable result. In this research, we showcase empirical data gathered through experiments, concerning fiducial markers in real and simulated environments, for achieving precise 2D pose estimation. In light of these measurements, we present analytical functions that estimate the variability in pose measurements. We empirically validate our approach within a 2D robot localization experiment, describing a methodology for estimating covariance model parameters from user measurements and a procedure for combining pose estimates across multiple markers.
We formulate a novel optimal control problem for MIMO stochastic systems encompassing mixed parameter drift, external disturbance, and observation noise within the system's dynamics. The proposed controller not only tracks and identifies drift parameters in finite time, but also steers the system toward the desired trajectory. Still, an incompatibility exists between control and estimation, obstructing the possibility of a straightforward analytic solution in the majority of instances. An algorithm for dual control, based on weight factors and innovation, is thus put forth. The control goal is modified by adding the innovation with an appropriate weighting factor, and a Kalman filter is implemented to track and estimate the transformed drift parameters. The degree of drift parameter estimation is calibrated by the weight factor, thereby achieving a balanced interaction between control and estimation. The optimal control is obtained through the solution to the adjusted optimization problem. The analytic solution of the control law can be computed via this strategic approach. The control law's optimality in this paper arises from the integration of drift parameter estimation within the objective function, unlike suboptimal control laws, where control and estimation are performed in separate, less optimal, components in other studies. An optimal balance between optimization and estimation is realized by the proposed algorithm. Numerical trials in two separate contexts validate the algorithm's performance.
The utilization of satellite data with moderate spatial resolution, specifically 20-30 meters from the new Landsat-8/9 Collection 2 (L8/9) Operational Land Imager (OLI) and Sentinel-2 Multispectral Instrument (MSI), offers a fresh approach to identifying and monitoring gas flaring (GF) in remote sensing applications, all thanks to the substantial reduction in revisit time, reaching approximately 3 days. This study ported the recently developed daytime gas flaring investigation approach (DAFI), initially intended for global gas flare site identification, mapping, and monitoring using Landsat 8 infrared data, to a virtual constellation (VC) combining Landsat 8/9 and Sentinel 2 data. The objective was to evaluate the approach's performance in understanding the characteristics of gas flares within the space-time context. Iraq and Iran, ranked second and third in 2022's top 10 gas flaring countries, serve as prime examples of the improved accuracy and sensitivity (+52%) of the developed system, as demonstrated by the findings for these regions. As a result of this study, a more realistic model of GF sites and their behaviors has been constructed. The original DAFI configuration has been augmented with a new step designed to quantify the radiative power (RP) of GFs. The daily OLI- and MSI-based RP data, presented across all sites using a modified RP formula, indicated a positive correlation, as determined by preliminary analysis. The annual RPs computed in Iraq and Iran showed 90% and 70% agreement respectively, in conjunction with their gas-flared volumes and carbon dioxide emissions. In light of gas flaring being a leading global source of greenhouse gases, the application of RP products may improve the global estimation of greenhouse gas emissions at more detailed spatial resolutions. By automatically analyzing gas flaring on a worldwide scale, DAFI, as a satellite tool, stands out for the achievements presented.
In order to properly evaluate the physical aptitude of patients with chronic diseases, healthcare professionals require a dependable tool. We sought to evaluate the accuracy of physical fitness test results derived from a wrist-worn device in young adults and individuals with chronic conditions.
Wrist-mounted sensors were worn by participants who then undertook two physical fitness assessments: the sit-to-stand (STS) and time-up-and-go (TUG) tests. Using Bland-Altman analysis, root-mean-square error, and the intraclass correlation coefficient (ICC), we examined the concordance of sensor-derived results with expected values.
Thirty-one young adults (group A; median age 25.5 years) and 14 people with chronic conditions (group B; median age 70.15 years) altogether participated in the study. STS (ICC) achieved a notable degree of concordance.
The operation involving 095 and ICC equals zero.
TUG (ICC) and the value 090 are related.
075 signifies the ICC's numerical designation.
The sentence, a delicate dance of meaning and form, gracefully unfolds. In young adult STS tests, the sensor provided the best estimations, showing a mean bias of 0.19269.
The study included individuals with chronic diseases (mean bias = -0.14) and those without (mean bias = 0.12).
Each carefully constructed sentence, a testament to the artist's skill, paints a vivid picture in the reader's mind. government social media The TUG test, performed on young adults, demonstrated the sensor's greatest estimation errors in the two-second period.
This study's findings indicate a concordance between the sensor's results and the gold standard's measurements during both STS and TUG assessments in both healthy young people and those with chronic illnesses.