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Abstract Developing energy-efficient and multifunctional wearable electronic textiles (E-textiles) is a significant challenge. This study investigates MXene-coated cellulose hybrid fibers, focusing on their electrical properties, heating performance, and thermal stability. The fabrication process involves continuous dipping of cellulose fibers into an aqueous MXene solution, resulting in the creation of MXene-coated cellulose hybrid fibers. We confirm the uniform coating of MXene sheets on the cellulose fiber surfaces, with increasing content throughout the dip coating cycle, as evidenced by X-ray diffraction and scanning electron microscopy analysis. The high thermal conductivity of MXene acts as a heat source, impacting the thermal stability of cellulose fibers at lower temperatures. Additionally, the electrical properties of MXene/cellulose hybrid fiber composites are influenced at elevated temperatures. Remarkably, the longitudinal electrical conductivity of the MXene-coated cellulose fiber composites exhibits a notable increase of 0.06 S/cm after the final coating cycle, demonstrating the effective and conductive nature of the layer-by-layer MXene network formed on the cellulose fibers.

Air quality in Seoul is significantly worse than in major OECD countries, with 1.2–3.5 times higher levels of fine dust and nitrogen dioxide. Photocatalytic reaction with Ca-bound catalyst efficiently removes nitrogen oxides (NOx), especially in building materials, promising solutions for NOx removal in urban air purification. This study therefore investigates the effect of various forms of titanium dioxide (TiO2) on the mechanical properties and NOx removal capability of foam concrete. To produce foam concrete, the type and amount of air foaming agent were optimized. Two types of commercially available TiO2 (P25 and NP600) were incorporated into the foam concrete, alongside synthesized TiO2-mayenite (as an intermixing powder or a coating material). Test results indicated that the incorporation of P25 and NP600 led to increased compressive strength and decreased porosity. The strength increased and porosity decreased, as the amount of TiO2 powders was increased. P25 outperformed NP600 in terms of the NOx removal capacity of foam concrete, with the peak NOx removal capacity (6.07 μmol/50 cm2·5 h) observed at a P25 content of 3%. An even higher NOx removal amount of 6.19 μmol/50 cm2·5 h was achieved by triple-coating the foam concrete surface with 10 wt% TiO2-mayenite. Considering the thickness of the coated TiO2-mayenite and economic feasibility, an approach with dual-coating emerged as the most suitable.

Carbon consuming concrete (CCC) represents an advanced sustainable concrete designed to optimize carbon sequestration efficiency. This study conducted preliminary tests on curing conditions to evaluate the effects of nanobubble water on the strength and carbon sequestration efficiency of concrete cured under various conditions. The curing conditions were characterized by temperature, duration, and the type of curing water utilized. The precipitation method was employed to validate the variation in the CO2-capturing capacity of nanobubble water (NBW), essential for carbon fixation within cementitious composites, as temperatures increased. Subsequently, compressive strength test and chemical analyses were performed on CCC manufactured under different curing conditions. Analysis techniques comprise differential thermogravimetry (DTG) and Fourier transform infrared spectroscopy (FT-IR). The carbon sequestration efficiency of CCC was observed to increase with shorter curing durations, and high temperatures could boost both the strength and carbon sequestration efficiency of CCC.

In May 2019, UAV photogrammetry using drones (unmanned aircraft) was conducted to investigate the spatial distribution characteristics of the seagrass habitat in Wan Island. Wan Is. sea was divided into 3 geographical areas (Site A, B, C) by referring to the seagrass distribution identified by the National Coastal seagrass forest precision survey (Ministry of Oceans and Fisheries, 2015), and contour lines were extracted from grid depth data. In addition, a 3-D benthic topographic map using DTM (Digital Terrain Model) was created to understand the characteristics and slope of the benthic topographic map. Through the analysis of the seagrass distribution results and the water depth results, it was confirmed that the boundary between the seagrass distribution in the outer and coastal areas converges to different water depth limits (within 10 m, and within 5 m), which is estimated to be based on the characteristics of the outer sea area. As a result of the analysis of the benthic topography, it was confirmed that the slope of the well-covered distribution was relatively gentle below 0.2~0.8 degrees, and the well-covered distribution was limited to the vicinity of the boundary where the slope changed rapidly. As a result of comparing the area of the seagrass distribution survey in 2015 and 2019, it was confirmed that the area was 238.4 ha and 1,070.9 ha, respectively, which was 4.5 times more widerly when performing Drone survey than diving survey. In order to understand the surrounding environment of the seagrass distribution site, satellite image data and license fishing ground information map at the time of drone shooting (May 2019) were checked. As a result, seaweed (Kelp, Sea mustard seaweed, Seaweed, Seaweed fulvescens, etc.) and shellfish (Abalone) were densely distributed, and most of the facilities except for Seaweed fulvescens farms were separated from their habitat. Drone survey confirmed Zostera marina, Zostera caulescens, and Zostera japonica in Wan Is., but no Phyllospadix iwatensis and Halophila nipponica were identified in 2015. It was confirmed that there was a limit to classifying the types of vegetation due to the characteristics of Phyllospadix iwatensis attached to the rock substrate, and in the case of Halophila nipponica with short leaves of 2 to 3 cm, they were not exposed to the water even at low tide, so there was a limit to detection using drones. These research results are expected to be useful data for grasping the characteristics of a wide range of seagrass habitats in other seas in the future.

Rising seawater temperatures are causing geographic shifts in the composition and abundance of the marine plankton that make up the microbial food web. Over the past few years, the water temperature around the Korea Strait has been increasing rapidly. Twelve cruise surveys were conducted in the Jeju Strait between 2017 and 2019 to monitor the presence of the tropical dinoflagellate genera Ornithocercus and Triposolenia, which are brought in by the Jeju Warm Current. Additionally, passive tracer experiments were performed using the Regional Ocean Modeling System to understand how the warm currents impact the Jeju Strait. The results of these simulations were then compared against the distribution ranges and abundance of Ornithocercus and Triposolenia. The study found that there were significant seasonal variations in abundance and spatial distribution of the tropical dinoflagellates during the sampling period, particularly during September and November when they were highly abundant and widely distributed. These patterns were closely related to the intensity and path of the Jeju Warm Current, particularly from southeastern offshore (EKB02; Eastern Kuroshio Branch02) rather than from southwestern offshore (EKB01; Eastern Kuroshio Branch01) of Jeju Island. The study also found no tropical dinoflagellates at any of the stations near the south coast of Korea during the sampling period. These findings suggest that the Ornithocercus and Triposolenia tropical dinoflagellate genera may serve as useful biological indicators to monitor the advection of warm currents into the Jeju Strait, Korea.

Abstract In this paper, we introduce a modified Krasnoselski–Mann type iterative method for capturing a common solution of a split mixed equilibrium problem and a hierarchical fixed point problem of a finite collection of k-strictly pseudocontractive nonself-mappings. Many of the algorithms for solving the split mixed equilibrium problem involve a step size which depends on the norm of a bounded linear operator. Since the computation of the operator norm is very difficult, we formulate our iterative algorithm in such a way that the implementation of the proposed algorithm does not require any prior knowledge of operator norm. Weak convergence results are established under mild conditions. We also establish strong convergence results for a certain class of hierarchical fixed point and split equilibrium problem. Our results generalize some important results in the recent literature.

A porous photocatalyst concrete filter (deNOx PCF) is successfully manufactured to reduce NOx by mixing TiO2 photocatalyst with lightweight aerated concrete. From the results, 4% infusion rate of each foaming agent provided the smallest change of the height, and the optimal quality of the air bubbles can be produced by using foaming agent B with 4% of infusion rate. When 3% of TiO2 photocatalyst was mixed, less irregular and relatively homogeneous pores were formed on the surface with white color due to the proper amount of photocatalyst applied. For 3% of photocatalyst mixed with deNOx PCF, 1.03 μmol/hr of NO was reduced equivalent to 10.99% of NO reduction, suggesting that the TiO2 photocatalyst dispersed in the continuous and well-developed pores inside the specimen successfully performed the removal of NO flowing through deNOx PCF using synergistic effects of adsorption and photodegradation reaction. Finally, the specimen of porous deNOx PCF for reducing NOx developed in this study can be applied to various construction sites and the air quality can be solved by reducing NOx contributing to the formation of fine particles.

Although ulcerative colitis (UC) is confined to colonic and rectal mucosa in a continuous fashion, recent studies have also demonstrated the involvement of upper gastrointestinal tract as diagnostic endoscopy becomes more available and technically advanced. The pathogenesis of UC is not well established yet. It might be associated with an inappropriate response of host mucosal immune system to gut microflora. Although continuous and symmetric distribution of mucosal inflammation from rectum to colon is a typical pattern of UC, clinical feature and course of atypically distributed lesions in UC might also help us understand the pathogenesis of UC. Herein, we report a case of duodenal involvement of UC which successfully remitted after infliximab therapy. Endoscopic and pathologic findings before and after administration of anti-tumor necrosis factor suggest that the pathogenesis of upper gastrointestinal involvement of UC may be similar to that of colon involvement.

Abstract New Hermite–Hadamard type inequalities are established. Some corresponding examples are also discussed in detail.

The junction temperature, one of the major parameters that strongly affect the performance of light-emitting diodes (LEDs), increases during operation because of the power dissipated as heat within an LED device. Therefore, LED devices with poor characteristics are expected to have higher junction temperatures for the same driving conditions. In this study, an observation contrary to this expectation is presented: a deep-ultraviolet LED device with superior electrical characteristics shows a higher junction temperature at the same input electrical power than a device with poor characteristics. A simple equivalent circuit comprising a diode, a series resistor, and shunt components is employed to elucidate this counter-intuitive observation by considering the possible heat sources inside the LED device. It is found that the junction temperature is mainly dominated by the power dissipated at the diode instead of the other possible heat sources including the Joule heating effect of the resistive components.

As the next-generation display technology, microscale light-emitting diode (μ-LED) displays have attracted significant attention recently. For applying μ-LEDs as direct emissive pixels in everyday display applications, many chips in a relatively small-sized wafer must be relocated and distributed quickly over a wide screen area via so-called transfer technology. After a brief review of current conventional transfer technologies for placing μ-LEDs on a wide screen, for perspective, a new and versatile delivery technique for μ-LEDs is presented, in which an LED chip is converted to a ball shape in order to facilitate handling and processing of μ-LEDs for practical applications. Plausible procedures including the formation, arrangement, and removal of the plastic ball are discussed to envision potential impacts of the technology.

Background : Due to its anatomical location, the external ear is easily exposed and damaged due to trauma, weathering, and inflammation. Therefore, depending on the patient’s age, different cutaneous diseases can occur. In addition, because of its small percentage of the overall body area, patients and doctors may miss observing dermatologic diseases of the ear. The purpose of this study was to provide information on the most common dermatologic diseases according to the location on the external ear. Methods : This retrospective study was conducted on patients who visited the Department of Dermatology of Chosun University Hospital in the past 7 years. Results : We included 269 patients and categorized their ear lesions according to 8 anatomical locations and 5 types of dermatologic diseases. In older patients over 60 years of age, the most common site of dermatologic disease was the postauricular region (33.9%), followed by the antihelix (19.4%), and earlobe (12.9%). The most common dermatologic disease was benign tumor (53.2%), followed by malignant and premalignant tumors (32.3% and 9.7%, respectively). Conclusion : The proportion of older adults with premalignant and malignant diseases was relatively high and these were most commonly observed in the antihelix and postauricular area. Therefore, it is important to aware the need for the examination, diagnosis, and treatment of disease in the antihelix and postauricular area.

ObjectiveTo evaluate the compliance and satisfaction of rehabilitation recommendations for advanced cancer patients hospitalized in the palliative care unit.MethodsAdvanced cancer patients admitted to a hospice palliative care unit were recruited. Patients with advanced cancer and a life expectancy of less than 6 months, as assumed by the oncologist were included. Patients who were expected to die within 3 days were excluded. ECOG and Karnofsky performance scales, function ambulatory category, level of ambulation, and survival days were evaluated under the perspective of comprehensive rehabilitation. Problem-based rehabilitations were provided categorized as physical therapy at the gym, bedside physical therapy, physical modalities, medications and pain intervention. Investigation of compliance for each category was completed. Patient satisfaction was surveyed using a questionnaire.ResultsForty-five patients were recruited and received evaluations for rehabilitation perspective. The subjects were reported to have gait-related difficulties (71.1%), pain (68.9%), poor medical conditions (68.9%), bladder or bowel problems (44.4%), dysphagias (11.1%), mental status issues (11.1%), edemas (11.1%), spasticity (2.2%), and pressure sores (2.2%). In the t-test, patients with good compliance for GymPT showed higher survival days (p

In this paper, our goal was to establish the relationship between solutions of local sharp vector variational type inequality and sharp efficient solutions of vector optimization problems, also Minty local sharp vector variational type inequality and sharp efficient solutions of vector optimization problems, under generalized approximate η-convexity conditions for locally Lipschitzian functions.

Unassisted water splitting by tandem photoelectrochemical and photovoltaic devices requires optimization of the absorbance and transmittance properties of the front photoelectrode. Here, Shi et al. use a conductive distributed Brag reflector to harvest photons of different wavelengths in the two subcells.

A genetic algorithm is employed to find an optimum epitaxial structure of multiple quantum wells (MQWs) and electron-blocking layer (EBL) for a GaInN-based light-emitting diode (LED). The optimized LED is composed of locally Si-doped quantum barriers (QBs) in the MQWs and a quaternary heterostructured AlGaInN EBL having a polarization-induced electric field directed oppositely to that of a conventional AlGaN EBL. The optimized LED shows 15.6% higher internal quantum efficiency, 24.6% smaller efficiency droop, and 0.21 V lower forward voltage at 200 A/cm2 comparing to the reference LED, which has fully Si-doped QB and 20-nm-thick Al0.19Ga0.81N EBL. We find that local Si doping near the QB/QW interface compensates the negative polarization-induced sheet charge at the interface and reduces electric field in the QWs, thereby enhancing electron-hole wave function overlap. In addition, the inverted polarization field in the quaternary EBL provides a high barrier for electrons but a low barrier for holes, resulting in enhanced electron-blocking and hole-injection characteristics.

Few layer hexagonal boron nitride (h-BN) films were grown on 2-inch sapphire substrates by using metal-organic chemical vapor deposition (MOCVD) with two different carrier gases, hydrogen (H2) and nitrogen (N2). Structural, optical and electrical properties of the MOCVD-grown h-BN films were systematically investigated by various spectroscopic analyses and electrical conduction measurement. Based on the experimental findings including narrower X-ray photoelectron spectra, reduced intensity of the shoulder peaks in near edge X-ray absorption fine structure spectra, and decreased electrical conduction by more than three orders of magnitude when H2 carrier gas is employed, it was concluded that H2 has an advantage over N2 as the carrier gas for MOCVD growth of h-BN which is attributed to the healing of crystalline defects by etching and regrowth processes occurring under the pulsed source-injection mode.

This paper deals with designing a new iteration scheme associated with a given scheme for contraction mappings. This new scheme has a similar structure to that of the given scheme, in which those two iterative schemes converge to the same fixed point of the given contraction mapping. The positive influence of feedback parameters on the convergence rate of this new scheme is investigated. Moreover, the derived convergence and comparison results can be extended to nonexpansive mappings. As an application, the derived results are utilized to study the synchronization of logistic maps. Two illustrated examples are used to reveal the effectiveness of our results.

To develop a high-performance shrinkage reducing agent, this study investigated several shrinkage reducing materials and supplements for those materials. Fluidity and air content were satisfactory for the various shrinkage reducing materials. The decrease in viscosity was the lowest for glycol-based materials. The decrease in drying shrinkage was most prominent for mixtures containing glycol-based materials. In particular, mixtures containing G2 achieved a 40% decrease in the amount of drying shrinkage. Most shrinkage reducing materials had weaker level of compressive strength than that of the plain mixture. When 3% triethanolamine was used for early strength improvement, the strength was enhanced by 158% compared to that of the plain mixture on day 1; enhancement values were 135% on day 7 and 113% on day 28. To assess the performance of the developed high-performance shrinkage reducing agent and to determine the optimal amount, 2.0% shrinkage reducing agent was set as 40% of the value of the plain mixture. While the effect was more prominent at higher amounts, to prevent deterioration of the compressive strength and the other physical properties, the recommended amount is less than 2.0%.

The effects of the hole injection modulated by using a three-terminal GaInN-based light emitter, light-emitting triode (LET), on carrier recombination behavior and efficiency droop are investigated. It was found that the lateral electric field created by applying voltage bias between the two anodes effectively reduces efficiency droop as well as dynamic conductance of LETs. Detailed analyses of LETs under various operation conditions by APSYS simulations reveal that the asymmetry in carrier transport between electrons and holes is alleviated by promoted injection of hot holes over the potential barrier, increasing the hole concentration as well as the radiative recombination rate in the multiple quantum well active region.

We prove strong and Δ-convergence theorems for generalized nonexpansive mappings in uniformly convex hyperbolic spaces using S-iteration process due to Agarwal et al. As uniformly convex hyperbolic spaces contain Banach spaces as well as CAT(0) spaces, our results can be viewed as extension and generalization of several well-known results in Banach spaces as well as CAT(0) spaces.

The effect of strongly-imbalanced carrier concentration and mobility on efficiency droop is studied by comparing the onset voltage of high injection, the onset current density of the droop, and the magnitude of the droop, as well as their temperature dependence, of GaInN-based blue and green light-emitting diodes (LEDs). An n-to-p asymmetry factor is defined as σn/σp, and was found to be 17.1 for blue LEDs and 50.1 for green LEDs. Green LEDs, when compared to blue LEDs, were shown to enter the high-injection regime at a lower voltage, which is attributed to their less favorable p-type transport characteristics. Green LEDs, with lower hole concentration and mobility, have a lower onset current density of the efficiency droop and a higher magnitude of the efficiency droop when compared to blue LEDs. The experimental results are in quantitative agreement with the imbalanced carrier transport causing the efficiency droop, thus providing guidance for alleviating the phenomenon of efficiency droop.

The purpose of the paper is to present a new iteration method for finding a common element for the set of solutions of equilibrium problems and of operator equations with a finite family of λi-inverse-strongly monotone mappings in Hilbert spaces.

An innovative nanoscale ZnO/polybutadiene rubber composite (ZBRC) was developed as a valid alternative to TiO2 particles or immobilized TiO2 for the mineralization of chlorinated hydrocarbons without difficulties in the recovery of nanoscale photocatalyst particles. A synergistic increase in the removal of 1,1,2-trichloroethylene (TCE) through the coupled reaction processes (i.e., sorption, photolysis, and photocatalysis) was observed because sorption of TCE to the ultraviolet(UV)-transparent polybutadiene rubber occurred, and was coupled with the heterogeneous photocatalytic reactions with nanoscale ZnO particles on the surface of ZBRC. The removal rate of TCE decreased with an increase in the initial concentration of TCE because of both inhibited generation of electron–hole pairs and deficiency of photons to activate ZnO particles. Also, the TCE removal rate increased as the loading amount of ZBRC increased. Based on satisfactory linear regressions (R2 ≥ 0.94) between the apparent degradation rate constant (Kapp) and the initial concentration vs. the ZBRC loading amount, the Kapp values can be estimated, a priori, without performing photocatalytic experiments. The removal efficiencies were more significantly affected by the changes in the initial concentration of TCE and the ZBRC loading amounts than by the changes in light intensity and pH in aqueous solutions. From the results of response surface analysis, the greater removal efficiencies of TCE were achieved with higher pH values, greater amounts of ZBRC, and greater intensity of light. Based on these results, newly-developed ZBRC with both high removal efficiency and low cost performs as a valid alternative to TiO2 particles or immobilized TiO2 for the mineralization of chlorinated hydrocarbons in various environmental and industrial matrices.

We introduce the notion of asymptotically almost nonexpansive curves which include almost-orbits of commutative semigroups of asymptotically nonexpansive type mappings and study the asymptotic behavior and prove nonlinear ergodic theorems for such curves. As applications of our main theorems, we obtain the results on the asymptotic behavior and ergodicity for a commutative semigroup of non-Lipschitzian mappings with nonconvex domains in a Hilbert space.

An implicit iterative process is considered. Strong and weak convergence theorems of common fixed points of a finite family of asymptotically pseudocontractive mappings in the intermediate sense are established in a real Hilbert space.

A new nonlinear mapping is introduced. The convergence of Ishikawa iterative processes for the class of asymptotically pseudocontractive mappings in the intermediate sense is studied. Weak convergence theorems are established. A strong convergence theorem is also established without any compact assumption by considering the so-called hybrid projection methods.

The purpose of this paper is to present a regularization variant of the inertial proximal point algorithm for finding a common element of the set of solutions for a variational inequality problem involving a hemicontinuous monotone mapping A and for a finite family of λi-inverse strongly monotone mappings {Ai}i=1N from a closed convex subset K of a Hilbert space H into H.

We introduce and study a class of η-generalized vector variational-like inequalities and a class of η-generalized strong vector variational-like inequalities in the setting of Hausdorff topological vector spaces. An equivalence result concerned with two classes of η-generalized vector variational-like inequalities is proved under suitable conditions. By using FKKM theorem, some new existence results of solutions for the η-generalized vector variational-like inequalities and η-generalized strong vector variational-like inequalities are obtained under some suitable conditions.

The purpose of this paper is to use the modified block iterative method to propose an algorithm for solving the convex feasibility problems for an infinite family of quasi-ϕ-asymptotically nonexpansive mappings. Under suitable conditions some strong convergence theorems are established in uniformly smooth and strictly convex Banach spaces with Kadec-Klee property. The results presented in the paper improve and extend some recent results.

We study the strong convergence of two kinds of viscosity iteration processes for approximating common fixed points of the pseudocontractive semigroup in uniformly convex Banach spaces with uniformly Gâteaux differential norms. As special cases, we get the strong convergence of the implicit viscosity iteration process for approximating common fixed points of the nonexpansive semigroup in Banach spaces satisfying some conditions. The results presented in this paper extend and generalize some results concerned with the nonexpansive semigroup in (Chen and He, 2007) and the pseudocontractive mapping in (Zegeye et al., 2007) to the pseudocontractive semigroup in Banach spaces under different conditions.

We introduce a new one-step iterative process and use it to approximate the common fixed points of two asymptotically nonexpansive mappings through some weak and strong convergence theorems. Our process is computationally simpler than the processes currently being used in literature for the purpose.

We consider the weakly efficient solution for a class of nonconvex and nonsmooth vector optimization problems in Banach spaces. We show the equivalence between the nonconvex and nonsmooth vector optimization problem and the vector variational-like inequality involving set-valued mappings. We prove some existence results concerned with the weakly efficient solution for the nonconvex and nonsmooth vector optimization problems by using the equivalence and Fan-KKM theorem under some suitable conditions.

The convex feasibility problem (CFP) of finding a point in the nonempty intersection ∩i=1NCi is considered, where N≥1 is an integer and each Ci is assumed to be the fixed point set of a nonexpansive mapping Ti:E→E, where E is a reflexive Banach space with a weakly sequentially continuous duality mapping. By using viscosity approximation methods for a finite family of nonexpansive mappings, it is shown that for any given contractive mapping f:C→C, where C is a nonempty closed convex subset of E and for any given x0∈C the iterative scheme xn+1=P[αn+1f(xn)+(1−αn+1)Tn+1xn] is strongly convergent to a solution of (CFP), if and only if {αn} and {xn} satisfy certain conditions, where αn∈(0,1),Tn=Tn(modN) and P is a sunny nonexpansive retraction of E onto C. The results presented in the paper extend and improve some recent results in Xu (2004), O'Hara et al. (2003), Song and Chen (2006), Bauschke (1996), Browder (1967), Halpern (1967), Jung (2005), Lions (1977), Moudafi (2000), Reich (1980), Wittmann (1992), Reich (1994).

The dependence of the polarization-induced electric field in GaInN/GaN multiple-quantum-well light-emitting diodes (LEDs) on the GaN quantum barrier (QB) thickness is investigated. Electrostatic arguments and simulations predict that a thin QB thickness reduces the electric field in the quantum wells (QWs) and also improves the LED efficiency. We experimentally demonstrate that the QW electric field decreases with decreasing QB thickness. The lower electric field results in a better overlap of electron and hole wave functions and better carrier confinement in the QWs. A reduced efficiency droop and enhanced internal quantum efficiency is demonstrated for GaInN/GaN LEDs when the QB thickness is reduced from 24.5 to 9.1 nm.