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This paper delves into the advantages of authentication algorithms employing self-sovereign identity, highlighting a reduced communication overhead and the elimination of single points of failure. However, it acknowledges the vulnerability of digital wallets to real-world issues like loss or theft. To address these challenges, we propose an efficient key backup and recovery protocol based on the FROST threshold signature algorithm. This protocol involves trusted third parties and backup devices, ensuring secure secret key sharing and rapid key recovery. Performance evaluations, including key recovery time, demonstrate the protocol's efficiency and reliability, bolstering the overall robustness of self-sovereign identity systems. [ABSTRACT FROM AUTHOR]

Stock price prediction has been a subject of significant interest in the financial mathematics field. Recently, interest in natural language processing models has increased, and among them, transformer models, such as BERT and FinBERT, are attracting attention. This study uses a mathematical framework to investigate the effects of human sentiment on stock movements, especially in text data. In particular, FinBERT, a domain-specific language model based on BERT tailored for financial language, was employed for the sentiment analysis on the financial texts to extract sentiment information. In this study, we use "summary" text data extracted from The New York Times, representing concise summaries of news articles. Accordingly, we apply FinBERT to the summary text data to calculate sentiment scores. In addition, we employ the LSTM (Long short-term memory) methodology, one of the machine learning models, for stock price prediction using sentiment scores. Furthermore, the LSTM model was trained by stock price data and the estimated sentiment scores. We compared the predictive power of LSTM models with and without sentiment analysis based on error measures such as MSE, RMSE, and MAE. The empirical results demonstrated that including sentiment scores through the LSTM model led to improved prediction accuracy for all three measures. These findings indicate the significance of incorporating news sentiment into stock price predictions, shedding light on the potential impact of psychological factors on financial markets. By using the FinBERT transformer model, this study aimed to investigate the interplay between sentiment and stock price predictions, contributing to a deeper understanding of mathematical-based sentiment analysis in finance and its role in enhancing forecasting in financial mathematics. Furthermore, we show that using summary data instead of entire news articles is a useful strategy for mathematical-based sentiment analysis. [ABSTRACT FROM AUTHOR]

In digital identity authentication, credentials are typically stored in a digital wallet and authenticated through a single key-based signature and public key verification. However, ensuring compatibility between systems and credentials can be challenging and the existing architecture can create a single point of failure, which can hinder system stability and prevent data interchange. To address this problem, we propose a multiparty distributed signature structure using FROST, a Schnorr signature-based threshold signature algorithm, applied to the WACI protocol framework for credential interaction. This approach eliminates a single point of failure and secures the signer's anonymity. Additionally, by following standard interoperability protocol procedures, we can ensure interoperability during the exchange of digital wallets and credentials. This paper presents a method that combines a multiparty distributed signature algorithm and an interoperability protocol, and discusses the implementation results. [ABSTRACT FROM AUTHOR]

Real-time monitoring of suspended particulate matter (PM) has become essential in daily life due to the adverse effects of long-term exposure to PMs on human health and ecosystems. However, conventional techniques for measuring micro-scale particulates commonly require expensive instruments. In this study, a smartphone-based device is developed for real-time monitoring of suspended PMs by integrating a smartphone-based digital holographic microscopy (S-DHM) and deep learning algorithms. The proposed S-DHM-based PM monitoring device is composed of affordable commercial optical components and a smartphone. Overall procedures including digital image processing, deep learning training, and correction process are optimized to minimize the prediction error and computational cost. The proposed device can rapidly measure the mass concentrations of coarse and fine PMs from holographic speckle patterns of suspended polydisperse PMs in water with measurement errors of 22.8 ± 18.1% and 13.5 ± 9.8%, respectively. With further advances in data acquisition and deep learning training, this study would contribute to the development of hand-held devices for monitoring polydisperse non-spherical pollutants suspended in various media. [ABSTRACT FROM AUTHOR]

Magnetocaloric properties of (La 1- x Nd x) 2 Fe 10.7 Mn 0.3 Si 2 H y (x = 0.1 and 0.2) are evaluated to develop a room-temperature magnetic refrigerant. While Nd which is introduced to reduce the thermal hysteresis has a negligible effect on magnetic properties, the partial replacement of Fe with Mn converted the first-order magnetic transition to a second-order and T C is reduced by 50 K to near room temperature. The peak entropy change, Δ S M | pk values are 10.4 J kg−1 K−1 (at 290 K) for x = 0.1 and 10.6 J kg−1 K−1 (at 286 K) for x = 0.2 with μ 0 ∆ H = 3 T. The maximum values of the adiabatic temperature change, Δ T ad are 4.11 K (at 283 K) for x = 0.1 and 4.05 K (at 289 K) for x = 0.2 with μ 0 ∆ H = 1.4 T. Because T C can be shifted by the addition of Mn to room temperature, this series of compounds can be used as an efficient magnetic refrigerant or a combination as a composite refrigerant for an active magnetic refrigeration cycle. • (La 1- x Nd x) 2 Fe 10.7 Mn 0.3 Si 2 H y was synthesized for room-temperature magnetic refrigeration. • Mn addition reduced thermal hysteresis of hydrogenated La(FeSi) 13 alloys. • The peak Δ S M of LaFeSi-based alloys were measured to be 10.4 J kg−1 K−1 and 10.6 J kg−1 K−1. • Δ T ad of (La 1- x Nd x) 2 Fe 10.7 Mn 0.3 Si 2 H y (x = 0.1 and 0.2) was measured to be 4 K. [ABSTRACT FROM AUTHOR]

The Pacific Island countries have a substantial socio-economic dependency on fisheries. Skipjack tuna is one of the most important species in the Western Central Pacific (WCP) and its catches in this region exhibit a spatio-temporal variability influenced by ocean conditions, mainly the El Niño-Southern Oscillation (ENSO). This study investigates the relationship between skipjack tuna catch amounts and environmental variables in the equatorial Pacific during 1990–2014, and evaluates the potential predictability of the catches based on their statistical relationship. A series of regressed and reconstructed spatial patterns of upper-ocean temperature, salinity, currents and precipitation represent ENSO-like variability, and their principal component time series are used to estimate the predictability of skipjack tuna catches in the Federated States of Micronesia (FSM). ENSO-like variability depicted from 100 m temperature and 5 m salinity in the equatorial Pacific exhibit a significant predictability for the annual catch amount in the FSM for several years with a training period of > 20 years. This suggests that the subsurface temperature or near surface salinity can be a better predictor of ecosystem variability than widely used sea surface temperature. Applications of this result to other species could have broad implications for the fishery industry in the WCP. [ABSTRACT FROM AUTHOR]

Modern wireless systems are evolving toward a heterogeneous environment where multiple radio access technologies (RATs) coexist. Most of the RATs in current use operate independently of each other, however, there is an increasing demand for coordination among different RATs in order to support exponentially growing wireless traffic. Our goal in this paper is to design a super-MAC that integrates multiple RATs in a tightly coupled manner. To this end, we propose an architecture for super-MAC, and develop an algorithm that splits IP traffic into multiple RATs and controls each RAT to exploit multi-RAT diversity. We prove the asymptotic optimality of the super-MAC algorithm by introducing a novel reference system that enables the analysis of the multi-RAT system where there is a mixture of slotted (such as cellular) and unslotted (such as WiFi) RATs. Through extensive simulations we show that the super-MAC algorithm can enhance the quality of service including throughput, energy efficiency, and fairness. [ABSTRACT FROM AUTHOR]

The morphological and mechanical characteristics of red blood cells (RBCs) largely vary depending on the occurrence of hematologic disorders. Variations in the rheological properties of RBCs affect the dynamic motions of RBCs, especially their rotational behavior. However, conventional techniques for measuring the orientation of biconcave-shaped RBCs still have some technical limitations, including complicated optical setups, complex post data processing, and low throughput. In this study, we propose a novel image-based technique for measuring 3D position and orientation of normal RBCs using digital in-line holographic microscopy (DIHM) and artificial intelligence (AI). Formaldehyde-fixed RBCs are immobilized in coagulated polydimethylsiloxane (PDMS). Holographic images of RBCs positioned at various out-of-plane angles are acquired by precisely manipulating the PDMS-trapped RBC sample attached to a 4-axis optical stage. With the aid of deep learning algorithms for data augmentation and regression analysis, the out-of-plane angle of RBCs is directly predicted from the captured holographic images. The 3D position and in-plane angle of RBCs are acquired by employing numerical reconstruction and ellipse detection methods. Combining these digital image processing techniques, the 3D positional and orientational information of each RBC recorded in a single holographic image is measured within 23.5 and 3.07 s, respectively. The proposed AI-based DIHM technique that can extract the 3D position, orientation, and morphology of individual RBCs would be utilized to analyze the dynamic translational and rotational motions of abnormal RBCs with hematologic disorders in shear flows through further research. • AI-based analysis of out-of-plane angles of RBCs was demonstrated. • 3D positions and in-plane angles of RBCs were measured using a DIHM technique. • 3D positions and orientations of RBCs recorded in a single hologram were measured. • This technique has a simpler optical setup and higher throughputs than others. • It would be utilized to analyze 3D dynamics of RBCs flowing in a microchannel. [ABSTRACT FROM AUTHOR]

Phytoremediation has emerged as an ecofriendly technique to reduce hazardous particulate matter (PM) in the air. Although previous studies have conducted statistical analyses to reveal PM removal capabilities of various plant species according to their leaf characteristics, the underlying physical mechanism of PM adsorption of plants remains unclear. Conventional methodologies for measuring PM accumulation usually require long-term field tests and provide limited understanding on PM removal effects of individual leaf traits of various plants. In this study, we propose a novel methodology which can compare the electrostatic interactions between PMs and plant leaves according to their trichome structures by using digital in-line holographic microscopy (DIHM). Surface characteristics of Perilla frutescens and Capsicum annuum leaves are measured to examine electrostatic effects according to the morphological features of trichomes. 3D settling motions of PMs near the microstructures of trichomes of the two plant species are compared in detail. To validate the PM removal effect of the hairy microstructures, a polydimethylsiloxane (PDMS) replica model of a P. frutescens leaf is fabricated to demonstrate accelerated settling velocities of PMs near trichome-like microstructures. The size and electric charge distributions of PMs with irregular shapes are analyzed using DIHM. Numerical simulation of the PM deposition near a trichome-like structure is conducted to verify the empirical results. As a result, the settling velocities of PMs on P. frutescens leaves and a PDMS replica sample are 12.11 ± 1.88% and 34.06 ± 4.19% faster than those on C. annuum leaves and a flat PDMS sample, respectively. These findings indicate that the curved microstructures of hairy trichomes of plant leaves increase the ability to capture PMs by enhancing the electric field intensity just near trichomes. Compared with conventional methods, the proposed methodology can quantitatively evaluate the settling velocity of PMs on various plant leaves according to the morphological structure and density of trichomes within a short period of time. The present research findings would be widely utilized in the selection of suitable air-purifying plants for sustainable removal of harmful air pollutants in urban and indoor environments. [Display omitted] • The physical mechanism of PM adsorption process of plant leaves is investigated. • Hairy microstructures on leaves increase electric field intensity near trichomes. • Electrostatic interactions between PMs and hairy plant leaves are demonstrated. • 3D settling motion of PMs near hairy trichomes on leaves is quantitatively measured. • Settling velocity of PMs is elevated near the hairy trichomes on leaves. [ABSTRACT FROM AUTHOR]

Cobalt hexacyanoferrate (CoHCF) suffers from low rate capability and lifespan because of the dissolution and structural instability of Co during cycling. A smaller active material can relieve the stress caused by volume change during cycling and enable shorter transport pathways. Here, particle size reduction is performed by reducing the mixing time or citrate concentration in the coprecipitation reaction to improve the rate capability and lifespan of CoHCF. The reduced mixing time produces smaller particles with enlarged active sites, thus improving the capacity. Upon coprecipitation at a low citrate concentration, particle precipitation at reduced sizes is achieved by preferential nucleation versus growth. Although lowering the citrate concentration enlarges the external surface area, the reduced redox-active Fe degrades the capacity. All CoHCF samples with small sizes achieved enhance rate capability and stability. In particular, the sample synthesized with a short mixing time (0 h) achieve a specific capacity of 122 mAh g−1 with improved rate capability (79.4%) and stability (79.3%) over 500 cycles. Structural distortions are relaxed because of the shortened transport pathways and relieved distortion owing to particle size reduction. This study paves the approach for fast rechargeable and long-lasting aqueous Na-ion batteries using CoHCF electrodes. [Display omitted] • A decreased mixing time or citrate concentration yielded smaller CoHCF particles. • The capacity, rate capability, and lifespan were improved with shorter mixing times. • The low citrate ion concentration increased Fe vacancies and decreased the capacity. • Fe vacancies limited Na access in the lattice, thus improving structural stability. • The reduced CoHCF particle size improved rate capability and lifespan. [ABSTRACT FROM AUTHOR]

The flexural resistance of fiber reinforced cementitious composites (FRCCs) under biaxial condition was investigated by using two different types of biaxial bending test methods: the biaxial flexural test (BFT) and the centrally loaded round panel test (RPT). The flexural responses of FRCCs under biaxial condition were then compared with those of FRCCs under uniaxial condition; i.e. four-points bending test (4PBT). The test results, including the equivalent biaxial strength and normalized energy absorption capacity of the RPT, were found to be clearly higher than those of the BFT, and completely different cracking behavior was observed between the two biaxial test methods; the BFT generated numerous randomly distributed micro-cracks at the bottom of specimens, whereas the RPT mostly showed three major cracks, with minor radial cracks around them. In addition, the equivalent flexural tensile strength and normalized energy absorption capacity of the FRCCs under biaxial condition were found to be higher than those under uniaxial condition. The energy absorption capacity and the ratio of flexural tensile strength to the direct tensile strength of FRCCs are dependent on the stress state. [ABSTRACT FROM AUTHOR]

Due to the tradeoff between capacity and fairness in a wide variety of networks, increasing one objective may deteriorate the other. This paper investigates the possibility of improving capacity and fairness at the same time, specifically in two-hop cellular networks. First, we prove that an achievable capacity region can be enlarged by using relay, i.e., the capacity and fairness tradeoff relationship is alleviated. To achieve the Pareto-efficient boundary of this enlarged capacity region, an appropriate scheduling algorithm should be developed. Thus, second, we propose a generalized opportunistic scheduling algorithm for relaying mode that can improve both capacity and fairness. Furthermore, we propose a heuristic algorithm with low complexity and signaling overhead for relaying mode. Extensive simulations under various configurations demonstrate that the proposed algorithm not only increases the throughput of each user but also effectively alleviates unfairness among users. [ABSTRACT FROM PUBLISHER]

A dual-mode CMOS power amplifier (PA) with an integrated tunable matching network is presented. A switched capacitor is fully analyzed to implement a tunable matching network in terms of power-handling capability, tuning ratio, quality factor, and linearity. Based on the presented consideration, a 3.3-V 2.4-GHz fully integrated CMOS dual-mode PA is implemented in a 0.18-\mum CMOS process. The PA has two power modes, high-power and low-power (LP), and each mode is optimally matched by the tunable matching network. The LP mode enables more than 50% dc current reduction from 0- to 10-dBm power range. The improved efficiency in this study is approximately twice that of other multimode CMOS PAs reported thus far. [ABSTRACT FROM PUBLISHER]

This study considers the minimum error discrimination of two quantum states in terms of a two-party zero-sum game, whose optimal strategy is a minimax strategy. A minimax strategy is one in which a sender chooses a strategy for a receiver so that the receiver may obtain the minimum information about quantum states, but the receiver performs an optimal measurement to obtain guessing probability for the quantum ensemble prepared by the sender. Therefore, knowing whether the optimal strategy of the game is unique is essential. This is because there is no alternative if the optimal strategy is unique. This paper proposes the necessary and sufficient condition for an optimal strategy of the sender to be unique. Also, we investigate the quantum states that exhibit the minimum guessing probability when a sender's minimax strategy is unique. Furthermore, we show that a sender's minimax strategy and a receiver's minimum error strategy cannot be unique if one can simultaneously diagonalize two quantum states, with the optimal measurement of the minimax strategy. This implies that a sender can confirm that the optimal strategy of only a single side (a sender or a receiver but not both of them) is unique by preparing specific quantum states. [ABSTRACT FROM AUTHOR]

Presents a study which synthesized ferromagnetic exchange-spring nanocomposite thin films from sputter-deposited cobalt platinum. Experimental details; Results and discussion; Conclusions.

Fatigue life in critical parts of structure components, which is subjected to variable amplitude loading, is a very complex subject. When a fatigue life is influenced by these load variations, accelerations and/or retardations in crack growth rate can occur. Thus, an accurate prediction of fatigue life requires an adequate evaluation of these stress interaction effects. There are many different indexes for calculating fatigue damage at critical locations. The crack severity index based on crack growth is one of the methodologies implemented for modern military aircrafts to define mission severity relative to a known reference usage. But, this index cannot consider stress interaction. In this study, a novel index was proposed to evaluate an effect for stress interaction by using entropy concept, and fatigue life prediction methodology was developed by using entropy index of stress interaction and crack severity index of effective stress. [ABSTRACT FROM PUBLISHER]

Abstract: Since the majority of schools are housed in buildings dating from the 1960s and 1970s, a comprehensive construction and renovation program of school buildings has been carried out to improve the educational conditions in Korea. However, classrooms and computer rooms, with pressed wood desks, chairs and furnishings, as well as construction materials, might have negative effects on the indoor air quality. Furthermore, most schools have naturally ventilated classrooms. The purpose of this study was to characterize the concentrations of different indoor air pollutants within Korean schools and to compare their indoor levels within schools according to the age of school buildings. Indoor and outdoor air samples of carbon monoxide (CO), carbon dioxide (CO2), particulate matter (PM10), total microbial count (TBC), total volatile organic compounds (TVOCs) and formaldehyde (HCHO) were obtained during summer, autumn and winter from three sites; a classroom, a laboratory and a computer classroom at 55 different schools. The selection of the schools was based on the number of years since the schools had been constructed. The problems causing indoor air pollution at the schools were chemicals emitted by building materials or furnishings, and insufficient ventilation rates. The I/O ratio for HCHO was 6.32 during the autumn, and the indoor HCHO concentrations (mean=0.16ppm) in schools constructed within 1 year were significantly higher than the Korean Indoor Air Standard, indicating that schools have indoor sources of HCHO. Therefore, increasing the ventilation rate by means of a mechanical system and the use of low-emission furnishings can play key roles in improving the indoor air quality within schools. [Copyright &y& Elsevier]

Over the past decade, a number of studies have demonstrated the resistance of cancer cells to conventional drugs and have recognized this as a major challenge in cancer therapy. While attempting to understand the underlying mechanisms of chemoresistance, several studies have suggested that the presence of cancer stem cells (CSCs) in tumors is one of the major pathways contributing toward resistance. Chemoresistance leads to cancer treatment failure and worsens the prognosis of patients. Natural herbal compounds are gaining attention as an alternative treatment strategy for cancer. These compounds may be effective against chemoresistant cells either alone or synergistically alongside conventional drugs, sensitizing cancer cells and enhancing the therapeutic efficacy. BRM270 is a natural compound made from seven herbal plant (Saururus chinensis, Citrus unshiu Markovich, Aloe vera, Arnebia euchroma, Portulaca oleracea, Prunella vulgaris var. lilacina and Scutellaria bacicalensis) extracts used in Asian traditional medicine and has the potential to target CSCs. Several studies have demonstrated the positive effects of BRM270 against chemoresistant cancer and its synergy alongside existing cancer drugs, including paclitaxel and gefitinib. These effects have been observed against various cancer types, including resistant non-small cell lung cancer (NSCLC), glioblastoma, multi-drug resistant osteosarcoma, cervical cancer, pancreatic cancer and hepatocarcinoma. The present review discusses the effects of BRM270 treatment against CSC-associated chemoresistance in common types of cancer. [ABSTRACT FROM AUTHOR]

The Black Lake rockslide is located on the east wall of an open-pit mine initially operated by LAB Chrysotile near Thetford Mines, Quebec. Movements were observed in July 2012 when a volume of 2.0 × 107 m3 was mobilized, destroying a large portion of Highway 112. Mining operations ceased in 2012, causing the complete shutdown of the pumping system whose goal was to prevent the rise of water level in the pit. As the water level increases in the pit, it is essential to determine the potential of tsunami generation by possible partially submerged rockslides and to understand the potential impacts. A series of possible scenarios have been analysed with regard to velocity and acceleration of the potential rockslide as well as the corresponding wave generation and inundation. Results from the simulation show that when the factor of safety of the global slope is less than unity, inundation would not reach the potentially vulnerable infrastructures. Maximum wave height will vary as a function of the filling of the lake, and the lower wave height relative to water depth will happen when the lake is completely filled. [ABSTRACT FROM AUTHOR]

Landslides are the second most important cause of tsunamis after earthquakes, and their potential for generating large tsunamis depend on the slide process. Among the world's largest submarine landslides is the Storegga Slide that generated a large tsunami over an ocean-wide scale, while no traces of a tsunami generated from the similar and nearby Trænadjupet Slide have been found. Previous models for such landslide tsunamis have not been able to capture the complexity of the landslide processes and are at odds with geotechnical and geomorphological data that reveal retrogressive landslide development. The tsunami generation from these massive events are here modeled with new methods that incorporate complex retrogressive slide motion. We show that the tsunamigenic strength is closely related to the retrogressive development and explain, for the first time, why similar giant landslides can produce very different tsunamis, sometimes smaller than anticipated. Because these slide mechanisms are common for submarine landslides, modeling procedures for dealing with their associated tsunamis should be revised. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe-AC/Fe 2 O 3 /PVA microgels were manufactured using a microfluidic approach. • The microgels were solidified via Schiff-base and acetalization reactions. • The microgels showed high adsorption selectivity and capacity for anionic dyes. • The microgels maintained a high reusability level of ∼ 85 % after five cycles. • The microgels can be easily recovered by an external magnetic field after adsorption. In this study, magneto-responsive iron-aminoclay/iron oxide/polyvinyl alcohol (Fe-AC/Fe 2 O 3 /PVA) composite microgels were successfully fabricated via a Schiff-base and acetalization reactions using a microfluidic approach. The as-prepared Fe-AC/Fe 2 O 3 /PVA composite microgels were used as adsorbents to remove organic dyes from aqueous solutions. The chemical cross-linking and morphology of the prepared microgel particles were evaluated using Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, optical microscopy, Brunauer–Emmett–Teller surface area analysis, and scanning electron microscopy. The Fe-AC/Fe 2 O 3 /PVA microgels served as an effective adsorbent by exhibiting a remarkable adsorption capacity for anionic dyes such as methyl orange (MO), Congo red (CR), and methyl blue (MB) owing to their fast diffusion kinetics, porous structures, and numerous amino groups. The microgels had maximum adsorption capacities of 457.31 mg/g for MO, 352.88 mg/g for CR, and 566.98 mg/g for MB. The prepared microgels were systematically evaluated for their adsorption behavior toward the anionic dyes from aqueous solutions at various process parameters, such as pH, contact time, and dye concentration. The adsorption process for the anionic dyes fitted well with the pseudo-second-order kinetic model and Sips isotherm model, verifying that the sorption process was mainly governed by chemisorption. Furthermore, the Fe 2 O 3 magnetic nanoparticle incorporation made it simple to separate the microgels from the aqueous solutions and reuse them. The microgels maintained an adsorption efficiency of above 80 % even after five adsorption–desorption cycles. These results demonstrate that the magneto-responsive Fe-AC/Fe 2 O 3 /PVA hybrid microgels are an effective and sustainable adsorbent for treating wastewater contaminated with anionic dyes. [ABSTRACT FROM AUTHOR]