Peripheral blood oxygen saturation (SpO 2) is an essential indicator of respiratory functionality and received increasing attention during the COVID-19 pandemic. Clinical findings show that patients can have significantly low SpO 2 before any obvious symptoms. Measuring individual's without having to come into contact with person lower risk cross contamination circulation problems. The prevalence smartphones has motivated researchers investigate methods for monitoring using smartphone...

This article studies the relation between electrocardiogram (ECG) and photoplethysmogram (PPG) investigates inference of ECG waveforms from PPG signals that can be obtained affordable wearable Internet-of-Things (IoT) devices for mobile health. In order to address this inverse problem, a transform is proposed map discrete cosine (DCT) coefficients each cycle those corresponding based on cardiovascular signal model. The method evaluated with different morphologies three benchmark data sets...

Objective: This study was designed to investigate bone properties using heel quantitative ultrasound (QUS) in young adults participating various sports. Methods: A cross sectional performed on Chinese male students (n = 55), aged 18–22 years. Subjects with previous fractures or suffering from any diseases known affect metabolism taking medication such an effect, were not included. The subjects categorised according their main sporting activities, including soccer 15) (a high impact, weight...

In the field of information forensics, many emerging problems involve a critical step that estimates and tracks weak frequency components in noisy signals. It is often challenging for prior art tracking to i) achieve high accuracy under conditions, ii) detect track multiple efficiently, or iii) strike good trade-off processing delay versus resilience tracking. To address these issues, we propose Adaptive Multi-Trace Carving (AMTC), unified approach detecting one more subtle very low...

Abstract This study is among the first to develop different prototypes of generative artificial intelligence (GenAI) chatbots powered by GPT-4 communicate hurricane preparedness information diverse residents. Drawing from Computers Are Social Actors paradigm and literature on disaster vulnerability cultural tailoring, we conducted a between-subjects experiment with 441 Black, Hispanic, Caucasian residents Florida. Our results suggest that GenAI varying in tone formality tailoring...

Content analysis breaks down complex and unstructured texts into theory-informed numerical categories. Particularly, in social science, this process usually relies on multiple rounds of manual annotation, domain expert discussion, rule-based refinement. In paper, we introduce SCALE, a novel multi-agent framework that effectively $\underline{\textbf{S}}$imulates $\underline{\textbf{C}}$ontent $\underline{\textbf{A}}$nalysis via $\underline{\textbf{L}}$arge language model (LLM)...

This study segments social media publics and analyzes their informational behaviors during organizational crises. With a public-centric perspective, our highlights how interact with each other (i.e., interdependence) share different information through crisis stages dynamics). Following the situational approach to segmentation, we identify types of influentials, broadcasters, followers) based on positions in an sharing network. Crisis managers are recommended pay more attention higher...

In this paper, the relation between electrocardiogram (ECG) and photoplethysmogram (PPG) signals is studied, waveform of ECG inferred via PPG signals. order to address inverse problem, a transform proposed map discrete cosine (DCT) coefficients each cycle those corresponding cycle. The resulting DCT are inversely transformed obtain reconstructed waveform. method evaluated on benchmark dataset subjects with variety combinations age weight. Experimental results show that can achieve high...

The electric network frequency (ENF) signal is an environmental signature that can be captured in audiovisual recordings made locations where there electrical activity. This influenced by the power grid which recording made, and recent work has shown it useful toward a number of forensics security applications. An under-studied area ENF research factors affect capture traces media recordings. Not all areas activity will carry prominent traces, strengths are vary from one to another. A...

Blood oxygen saturation (SpO$_2$) is an important indicator for pulmonary and respiratory functionalities. Clinical findings on COVID-19 show that many patients had dangerously low blood levels not long before conditions worsened. It therefore recommended, especially the vulnerable population, to regularly monitor level precaution. Recent works have investigated how ubiquitous smartphone cameras can be used infer SpO$_2$. Most of these are contact-based, requiring users cover a phone's...

Recent studies showed that subtle changes in human's face color due to the heartbeat can be captured by digital video recorders. Most existing work focused on still/rest cases or those with relatively small motions. In this work, we propose a heart-rate monitoring method for fitness exercise videos. We focus designing highly precise motion compensation scheme help of optical flow, and use information as cue adaptively remove ambiguous frequency components improving heart rates estimates....

Multiple videos capturing the same scene from possibly different viewing angles may be synthesized for novel immersive experience. Synchronization is an important task such applications involving multiple pieces of audio-visual data. In this work, we exploit electric network frequency (ENF) signal inherently embedded in soundtrack and/or image sequence video to temporally align recordings. ENF supply power distribution networks a grid. Its value fluctuates slightly its nominal 50 Hz or 60...

Electric network frequency (ENF) analysis is a promising forensic technique for authenticating multimedia recordings and detecting tampering. The validity of the ENF heavily relies on capability extracting high-quality signals from recordings. This paper analyzes compares two representative methods visual acquired by cameras using rolling-shutter mechanism. first method proposed in prior work, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML"...

This paper studies the authentication problem of specific pieces using mobile imaging devices. Prior work showing high matching accuracy has used normal vector field, which serves as a unique, microscopic, physically unclonable feature surfaces, estimated by consumer grade scanners. Industrial cameras were also to capture appearance surface rendered after field based on laws optics under semi-controlled lighting condition. In comparison, past explorations very limited and have not had...

In this paper, we study the problem of tracking multiple frequency components in a noisy signal using spectrogram-based method. Previous approaches such as image processing based or hidden Markov model methods may not be capable components, require extensive training, and time-consuming. To address these issues, propose an accurate efficient method named Adaptive Multi-Trace Carving (AMTC) for traces by iterative forward backward dynamic programming adaptive trace compensation. Experimental...

Electric Network Frequency (ENF) analysis is a promising forensic technique for authenticating digital recordings and detecting tampering within the recordings. The validity of ENF heavily relies on high-quality signals extracted from multimedia In this paper, we propose an signal extraction method rolling shutter acquired videos using periodic zero-padding. Our shows that proposed are not distorted component with highest signal-to-noise ratio located at intrinsic frequency. experimental...

Explicit formulas have been found for the effective piezoelectric coefficients of a 0-3 composite ferroelectric spherical particles in matrix. Tensile loading and hydrostatic conditions were studied. Assuming that both phases are dielectrically elastically isotropic, explicit expressions simple closed form d33, d31 dh derived terms constituents’ dielectric elastic properties constituents. Prediction specific systems was compared with experimental values from published works, good agreement...

We have investigated the effects of electrical conductivity constituents on dielectric and piezoelectric properties ferroelectric 0-3 composites. The time-dependent internal electric fields are first derived, which can be induced by an applied ac field in measurement or stress measurement. Our previously developed model [C. K. Wong, Y. M. Poon, F. G. Shin, J. Appl. Phys. 90, 4690 (2001)] has been extended to include additional contribution from conductivities frequency measurement,...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation C. K. Wong, F. G. Shin; A possible mechanism of anomalous shift asymmetric hysteresis behavior ferroelectric thin films. Appl. Phys. Lett. 24 January 2005; 86 (4): 042901. https://doi.org/10.1063/1.1853520 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks...

This work studies the paper authentication problem by exploiting optical features through mobile imaging devices to characterize unique, physically unclonable properties of surface. Prior showing high matching accuracy either used a consumer-level scanner for estimating projected normal vector field surface as feature authentication, or an industrial camera with controlled lighting obtain appearance image feature. In comparison, past explorations based on cameras were very limited and have...

We model the polarization behavior of ferroelectric multilayered composite structures including double layer and triple under action variable fields. The takes into consideration ceramic/polymer interfacial charge nonlinear hysteresis nature constituent materials to study poling process structures. results obtained are compared with available experimental on double-layer lead zirconate titanate/polyvinylidene fluoride-trifluoroethylene triple-layered triglycine sulphate/polyvinylidene...

Group testing can save resources in the context of ongoing COVID-19 pandemic. In group testing, we are given n samples, one per individual, and arrange them into m < pooled where each pool is obtained by mixing a subset individual samples. Infected individuals then identified using algorithm. this paper, use side information (SI) collected from contact tracing (CT) within nonadaptive/single-stage algorithms. We generate data incorporating CT SI characteristics disease spread between...