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본 연구는 증강현실(Augmented Reality, AR) 기반 교육에 대해 대학의 교수자들이 어떠한 인식을 지니는지를 분석하는 목적을 지닌다. 이를 위해 본 연구에서는 혼합연구 방법을 활용하여 AR 활용 교육에 대한 대학 교수자의 인식을 종합적으로 탐색하고자 하였다. 연구 결과, AR 기반의 효과적인 교육 운영을 위해 기자재 및 수업환경 마련, 교육적 지원이 필요한 것으로 인식하였다. 또한, 학습자들이 한정적으로 체험할 수 있다는 점, 기술적 오류가 빈번하게 발생할 수 있다는 점, 효과적인 교육을 위한 수업 설계가 어렵다는 점 등의 어려움을 인식하고 있었다. 본 연구는 AR을 활용한 교육의 운영을 위한 요구가 무엇인지를 종합적으로 확인하였다는 점에서 의미를 지닌다. 본 연구를 통해 확인된 문제점과 어려움을 중심으로 향후 연구에서는 최적화된 AR기반 교육에 대한 교수학습 모형의 개발과 환경 설계가 이루어질 필요가 있다. 또한, 대학의 기관 측면에서 교수자를 지원하기 위한 다양한 교육 프로그램의 개발 등 실제적이고 구체적인 방안이나 제도가 필요하다.

본 연구는 메타버스 관련 뉴스 빅데이터를 활용하여 메타버스의 주요 키워드와 토픽을 시기별로 파악하고, 메타버스의 주요 의제와 시사점을 도출하기 위해 수행되었다. 연구결과, 다음과 같은 시사점이 도출되었다. 첫째, 현재 명확하게 정의되지 않은 메타버스에 대한 종합적인 개념 및 정의에 대한 고찰이 필요하다. 둘째, 메타버스의 활용 범위 및 혁신이 지속 · 확대됨에 따라, 이용자들에게 가치 있는 생산성의 기회를 동일하게 제공해주어야 한다. 셋째, 메타버스와 현실세계, 그리고 메타버스와 또 다른 메타버스 플랫폼의 양방향 순환이 가능해야 할 것이다. 넷째, 건강한 메타버스의 생태계 구성을 위해서는 전반적인 메타버스에 대한 가이드라인 또는 에코시스템이 수립되어야 한다. 다섯째, 다양한 업계 및 현장전문가의 의견을 수렴하고, 그들 간의 커뮤니티를 활성화시켜 파편화되어 있는 지식 및 전문성이 공유될 수 있는 기회의 장을 열어주어야 한다. 여섯째, 메타버스 내 범죄, 격차 등 메타버스의 역기능에 대한 방안 마련이 필요하다.

Most of the electronic textiles (e-textiles) were fabricated by carbon-based materials such as graphene, carbon nanotube (CNT), and hybrids of graphene and CNTs due to their high electrical conductivity, flexibility, and good stability. However, it is difficult to synthesize a colored e-textiles because the carbon-based e-textiles have only a black color. In this study, we produced the chromatic e-textiles synthesized with different conductive polymer such as polyaniline, polythiophene, and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate). The chromatic e-textiles were simply fabricated by soaking commercial cotton into an aqueous conductive polymer solution. The chromatic e-textiles were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The electrical conductivity of the chromatic e-textiles was the order of 10−3 S/cm, which was maintained even under bending.

Electronic textiles (e-textiles) need to have high heat durability for various applications. However, current e-textiles are usually damaged by high-temperature processes. We report silk-based e-textiles fabricated by simple pyrolysis with axial stretching that demonstrate high electrical conductivity and thermal durability. The electrical conductivity of the proposed e-textiles was on the order of 103S/cm and the electrical characteristics were maintained even after heating and bending. Furthermore, we prepared e-textiles with various electronic properties, such as semiconducting, superconducting, and light-emitting properties, by depositing ZnO, MoSe2, and NbN onto the commercial silk-based e-textiles using sputtering and evaporation. We introduced a simple method for fabricating silk-based e-textiles with various electronic properties, which are compatible with the current textile industry.

Salt removal via formation of gas hydrate was investigated by experimental measurement of the salt concentration in filtered water and water retrieved from hydrate crystals. Gas hydrate formation was carried out at 277.15 K, using seawater of 3.4 wt% salinity and 3 mol% cyclopentane to water-cyclopentane mixture. Single-stage hydrate formation followed by filtration removed 63% of the salt ions. Successive washing treatment with 274.15 and 277.15 K freshwater was applied with different amounts of washing water, and several major cations and anions in seawater were analyzed in each treatment step. Ions having larger radii showed less salt removal by hydrate formation, and salt removal decreased as the conversion of water to hydrate progressed. However, salt removal was improved by washing treatment to nearly the same degree regardless of the kind of salt ions and the salt removal efficiency improved up to 42% more than that of filtration only. The results presented in this study can be used as basic design values for the development of a hydrate-based desalination process.

The equilibrium boundaries of CH 4 and CO 2 hydrates were examined in the presence of di-carboxylic acids, glutaric acid and malonic acid, at a mass fraction of 0.1 and 0.01. Including di-carboxylic acids in the water phase shifted the phase boundaries to higher pressure and lower temperature conditions. We attributed this to the formation of hydrogen bonding between the inhibitors and water molecules rather than to the formation of water structures serving as hydrate precursors. In addition, the inhibition effect of shorter carbon-chained malonic acid was better than that of longer-chained glutaric acid due to its higher mole fraction in water phase. This inhibition effect was compared with that of conventional thermodynamic hydrate inhibitors (THIs) used in commercial processes. The comparison showed that the effect of malonic acid was close to that of tri-ethylene glycol for inhibiting the CH 4 hydrate.

The expression of anti-freeze proteins (AFPs) on the Escherichia coli using the cell surface display (CSD) strategy was investigated to determine the feasibility of the method as a potential application of kinetic hydrate inhibitors. Monomers to hexamers of type II and III AFPs were displayed on the surfaces of bacterial cells. The kinetic inhibition performance of the AFPs on the synthetic natural gas hydrate formation was tested. The displayed AFPs exhibited higher KHI effectiveness with the increase in the number of peptides attached to the cells. In addition, best KHI performance of the AFPs could be achieved with higher dosages of the cultures when the concentration of the inducer is optimized, regardless of AFP type. Only a small portion of AFPs in the cell cultures exhibited considerable KHI performance, which implies that the CSD could be an effective strategy, reducing the cost for the production and purification of the AFPs.

To medically use and store proteins like enzymes, long-term maintenance of their activity must be considered. We examined the effectiveness of several methods for preserving the activity of three model-protein solutions. Solutions of catalase, L-lactate dehydrogenase, and carbonic anhydrase were used to form gas hydrates with xenon and natural gas. These enzyme aqueous solutions showed inhibitory effects on hydrate formation, and exhibited significant differences in induction time as well. The hydrates formed of enzyme solutions with xenon or natural gas are expected to have a better preservation effect than storage at room temperature and in liquid nitrogen. Changes in the activity of enzymes stored under different conditions were measured in relation to storage time. Storage in hydrate was good for maintaining the activity of catalase and L-lactate dehydrogenase. For carbonic anhydrase, the activity at room temperature was generally similar to that after storage in gas hydrate, but storing it in liquid nitrogen produced better results. For certain enzymes, storage in gas hydrates is expected to be a more effective method of maintaining activity than protein storage methods like freeze-drying, which causes mechanical damage to the protein.

With the goal of discovering a more effective type of thermodynamic hydrate inhibitors (THIs), the phase equilibrium conditions of CH4 hydrates were examined in the presence of morpholinium and piperidinium ionic liquids (ILs) at a mass fraction of 0.1. It was observed that the addition of ILs shifted the hydrate equilibrium conditions toward higher pressure and lower temperature compared with those of hydrates formed from pure water. Both cationic and anionic species influenced the equilibrium conditions of the CH4 hydrate. The piperidinium ILs showed better inhibition effect than did the morpholinium ILs at the same species of counteranions. The result may be due to the more hydrophobic nature of piperidinium ILs, which have a higher affinity for CH4 molecules. It was also seen that the inhibition effect of BF4– ions was stronger than that of Br– ions for both piperidinium and morpholinium ILs. Thus, the inhibition effect became stronger in the order: N-ethyl-N-methylpiperidinium tetrafluoroborate ([EMP...

As a concept technology for water desalination, a hydrate-based process involving water-immiscible hydrate former was proposed and is under development [1,2]. In this study, we focused on successive secondary treatment methods to improve the salt removal efficiency when the hydrate-based process was applied for water desalination. At first, hydrate formation reactions were carried out at atmospheric pressure and either 1.0 or 4.0 °C, with simulated brine of 3.5 wt.% NaCl and various centration of cyclopentane (from 1.0 to 5.0 mol%). Results showed that substantial conversion of water to hydrate was possible as the degree of subcooling became high. A water mixture with 3.0 mol% cyclopentane at 4.0 °C, was subjected to centrifuging, washing, or sweating to achieve additional salt removal. Centrifuging produced the best salt removal efficiency (average 96%). Washing with a suitable amount of freshwater could effectively improve salt removal (to 93%). Sweating for an appropriate amount of time could also reduce the salt attached to the crystal surface more than 95%, but in this case the amount of water produced was proportionally diminished. According to the result, optimized washing method can be a promising candidate to raise the efficiency of the hydrate-based desalination process.

High-performance carbon-based electronic textiles have recently been considered as the potential components for low-cost, multifunctional flexible and wearable electronics. Although many promising results have been reported to fabricate carbon textiles, they are not adoptable to the current textile industry, such as, nylon, cotton, polyester, and silk due to their chemical stability. Here, we report a facile way to prepare fully conductive, flexible, and stable reduced graphene oxide (RGO)-based textiles from yarns to fabrics using electrostatic interaction and hydrogen bonding. The electronic textiles using graphene oxide (GO) was fabricated by two methods. First the currently used textiles such as nylon, cotton, and polyester were functionalized with bovine serum albumin (BSA) by soaking 0.5 wt% BSA solution for 10 min a room temperature. The prepared BSA-coated textiles were immersed in 1.0 mg/ml GO solution with mild shaking. As a result, GO-wrapped textiles were obtained. In order to endow the conducting property in these textiles, the GO-wrapped textiles were reduced by hydroiodic acid or thermal treatment. After reduction process, the conductivity reached up to 10 S/cm, which can light a LED lamp. This conducting textile fabricated with cotton, polyester, and nylon can be achieved by BSA through the hydrogen bonding between the protein (BSA) and graphene oxide. Using this property, we also synthesized the electronic textiles with cocoon silk and spider web. Since they already have proteins, the electronic textiles was fabricated without BSA, which was produced by simply dipping the silk and spider web into the GO solution. Its conductivity is comparable to that with BSA. These electronic textiles exhibit excellent electromechanical stability under severe mechanical deformation and a large number of repetitive bending cycles. Figure 1