In recent years, the efficient and clean utilization of coal has been widely concerned by scholars at home and abroad. Despite the abundance of global coal resources, the deep utilization rate of coal is still insufficient. To address this challenge, it has been explored the development and preparation of coal-based high value-added carbonaceous materials. In the present study, a novel process was developed for the preparation of graphene using biphenyl sourced from low-rank coal. Using chemical vapor deposition (CVD) technology, it was successfully implemented for us to grow high-quality graphene on copper foils. The prepared graphene products were observed and characterized using Raman spectroscopy, optical microscopy and scanning electron microscopy techniques. The results of this research provide a new perspective for the utilization of low-rank coal resources.

In this study, in order to develop an foaming tablet product using yuzu powder, yuzu powder was manufactured using different drying methods such as freeze-drying, 60℃ drying, and 40℃ drying, and then quality characteristics and functionality were analyzed. The naringin content per g of yuzu powder was 8.9 mg for freeze-drying and 8.8 mg for 60℃ drying, and the hesperidin content per g of yuzu powder was highest at 53.6 mg for freeze-drying and 46.2 mg for 60℃ drying. followed by 40℃ drying (41.7 mg). The tyrosinase inhibitory activity of 60℃ dried powder was found to be twice as high as that of freeze dried powder. Accordingly, in order to develop an inner beauty product, foaming tablets were manufactured using hot air dried powder, and the quality characteristics and functional ingredients of the final foaming tablets were investigated. The foaming tablet prepared with yuzu powder content of 10 and 15% showed an inhibitory activity of tyrosinase of 73.7 %, which was 1.6 times higher than that of ascorbic acid (1 mM), which was a positive control, confirming its melanin production inhibition effect.

The objective of this study is to analyze the indoor air quality of multi-use facilities using an IoT-based monitoring and control system. Thise study aims to identify effective management strategies and propose policy improvements. This research focused on 50 multi-use facilities, including daycare centers, medical centers, and libraries. Data on PM10, PM2.5, CO2, temperature, and humidity were collected 24 hours a day from June 2019 to April 2020. The analysis included variations in indoor air quality by season, hour, and day of the week (including both weekdays and weekends). Additionally, ways to utilize IoT monitoring systems using big data were propsed. The reliability analysis of the IoT monitoring network showed an accuracy of 81.0% for PM10 and 76.1% for PM2.5. Indoor air quality varied significantly by season, with higher particulate matter levels in winter and spring, and slightly higher levels on weekends compared to weekdays. There was a positive correlation found between outdoor and indoor pollutant levels. Indoor air quality management in multi-use facilities requires season-specific strategies, particularly during the winter and spring. Furhtermore, enhanced management is necessary during weekends due to higher pollutant levels.

본 연구는 보육교사의 직무 스트레스가 보육서비스 질에 미치는 영향 관계를 분석하고, 그 영향 관계에서 긍정심리자본의 구조적 역할을 검증하여 보육서비스 질을 증진을 위한 방안을 마련하는 데 있다. Y시에 근무하 는 보육교사 250명을 대상으로 2024년 02월 01일부터 02월 28일까지 직접 방문하여 회수하였다. 이중 불성실한 설문지 24부를 제외한 226부를 자료 분석에 활용하였다. 연구결과는 첫째, 직무스트레스 수준이 보육서비 스 질에 부적(negative)으로 유의미하게 영향을 미치는 것으로 나타났다. 둘째, 보육교사의 직무스트레스는 긍정심리자본에 부적(negative)으로 유의 한 영향을 미치는 것으로 나타났다. 셋째, 긍정심리자본이 보육서비스 질에 정적(positive)으로 유의한 영향을 미치는 것으로 나타났다. 이러한 연구 결 과는 보육교사의 지니고 있는 긍정심리자본은 직무스트레스를 상쇄시키는 매개역할을 하고 있음을 시사한다.

This study aimed to determine the optimal method by analyzing how different fining agents affect the quality of Muscat of Alexandria (MoA) wine. In the initial investigation, MoA wine underwent treatment with bentonite, egg white, icing glass, polyvinylpolypyrrolidone (PVPP), silica, and gelatin. General quality characteristics (pH, total acidity, sugar content, specific gravity, alcohol, volatile acidity), functional components (total polyphenols, antioxidant activity, tannins), and L*, a*, b* values were analyzed. Following the analysis, bentonite demonstrated the best color improvement, while silica and gelatin exhibited high total acidity and effective color enhancement. Consequently, bentonite, gelatin, and silica were deemed suitable for MoA wine and were selected for further investigation. In the second clarification test, varied experiments were conducted on bentonite, silica, and gelatin selected in the first clarification test. Analysis of general quality characteristics and functionality by fining type and time after treatment for MoA wine showed no significant changes before and after treatment. However, an analysis of turbidity after 8 months for each fining agent revealed a superior turbidity improvement effect of 0.040 ± 0.001 in the bentonite treatment group. Additionally, the L value was favorable in the bentonite and silica treatments. Regarding the improvement effect of the b value, silica treatment demonstrated the best results, followed by gelatin treatment.

The objective of this study was to investigate the comparison of feeding a total mixed ration (TMR) containing imported alfalfa hay and TMR containing hot-air dried domestic alfalfa on rumination activity, milk production, and composition in lactating dairy cows. Ten Holstein dairy cows were divided into two groups: control (imported alfalfa hay + TMR) and treatment (hot-air dried domestic alfalfa + TMR) groups. The study was conducted over a total period of 18 days, including a 13-days adaptation period and a 5-days main experimental period. The results indicated no differences in total digestible nutrient and net energy intake between the imported and hot-air dried alfalfa. Body weight was not significantly different between the two groups (p>0.05), however, total feed intake and rumination time were significantly and tendentially higher in the treatment group compared with control group, respectively (p<0.001; p=0.075). Milk yield was not significantly different between the two groups (p>0.05), however, milk fat (kg) and lactose (%) concentration were significantly higher in the treatment group compared with control group (p=0.016; p=0.02). This study confirms that feeding TMR with hot-air dried domestic alfalfa results in no differences of feed intake, rumination activity, and milk productivity. Therefore, it is considered that hot-air dried domestic alfalfa can be used as a substitute for imported alfalfa on lactating dairy cows.

외국인 유학생이 꾸준히 증가함에 따라 정부는 ‘외국인 유학생 유치‧관 리 역량 인증제’를 시행하였다. 인증제는 외국인 유학생 유치 및 관리에 양적인 성장뿐만 아니라 질적인 성장에 목적을 두고 2012년 본격적으로 도입하였으며 현재는 ‘교육국제화역량 인증제’로 확대하여 실시되고 있 다. 이를 통해 교육의 질과 학생의 수준을 끌어올리고 있지만 인증제가 현실을 반영하지 못하는 부분이 있다. 이에 본고에서는 외국의 사례를 조사한 후 한국의 교육국제화역량 인증제가 어떻게 수정·보완되어 왔는 지 그동안의 변화 과정을 살펴보고 3주기 보완 체계가 진행 중인 현재의 평가 항목과 기준 내용의 보완점을 제언하였다. 제언의 내용은 크게 세 가지로 나누어 볼 수 있다. 먼저 불법체류율 산정 방식이다. 기존의 산정 방식은 모수와 분자의 조건을 동일하게 보았기 때문에 이를 악용하는 경 우도 있었다. 따라서 불법체류율 산정 방식을 수정해야 한다. 둘째, 학위 과정의 경우 공인 한국어능력 자격을 취득하지 않은 유학생 대상 한국어 강의에 대한 명확한 규정이 필요하며 구체적인 졸업 요건이 명시되어야 한다. 셋째, 어학연수과정의 학생수, 교원 자격증 수 등을 현장 상황을 파악하여 평가 기준을 높여야 한다.

안양천의 어류 군집 특성과 어류상에 대한 수질의 영향을 밝히기 위해 2022년 4~6월과 8~10월에 20개 지점을 2회 조사하였다. 조사 기간 동안 채집된 어류는 5목 10과 34종 3,186개체였다. 우점종은 피라미(Zacco platypus, 43.4%) 였고, 아우점종은 붕어(Carassius auratus, 10.1%), 그 다음으로 잉어(Cyprinus carpio, 7.6%), 참갈겨니(Zacco koreanus, 6.2%), 돌고기(Pungtungia herzi, 5.2%), 대륙송사리(Oryzias sinensis, 5.1%), 참붕어(Pseudorasbora parva, 4.7%), 긴몰개(Squalidus gracilis majimae, 4.4%), 버들치(Rhynchocypris oxycephalus, 3.5%), 치리(Hemiculter eigenmanni, 3.3%), 흰줄납줄개(Rhodeus ocellatus, 1.4%), 가숭어(Chelon haematocheilus, 1.0%) 등의 순으로 우세하 게 출현하였다. 출현종 중 한국고유종은 각시붕어(Rhodeus uyekii), 긴몰개, 몰개(Squalidus japonicus coreanus), 참갈 겨니, 얼록동사리(Odontobutis interrupta) 5종(14.7%)이었고, 외래종은 이스라엘잉어(Cyprinus carpio Israeli type), 블루길(Lepomis macrochirus), 배스(Micropterus salmoides), 구피(Poecilia reticulata) 4종(11.8%)이었다. 어류 군집 분석 결과, 우점도는 상류가 높았고 하류로 가면서 낮아졌으며, 다양도와 풍부도, 균등도는 본류보다 지류에서 높게 나타나는 경향을 보였다. 하천건강성을 평가한 결과, 7개 지점에서 보통(C), 8개 지점에서 나쁨(D), 5개 지점에서 매우 나쁨(E)으로 평가되어 좋지 않았다. 수질은 8개 지점을 평가한 결과, 4개 지점은 보통(III), 2개 지점은 나쁨(V), 1개 지점은 약간 나쁨(IV), 1개 지점은 약간 좋음(II)으로 평가되어, 전체적인 수질은 나쁘게 나타났으며, 수질이 하천건 강성과 어류의 서식에 큰 영향을 미치고 있는 것으로 추정되었다. 또한 안양천에 어도가 없는 보가 많이 설치되어 있어 어류의 이동에 장애물로 작용하고 있었다. 따라서 하천건강성을 높이고 안정적인 어류의 서식을 위해서는 수질을 개선할 수 있는 체계적인 관리방안이 필요하고 보에 어도 설치가 요구되었다.

In this study, various pre-treatment methods were evaluated for microalgae separation. These methods aimed to facilitate safe, rapid, and cost-effective online imaging for real-time observation and cell counting. As pre-treatment techniques, heating, chemical hydrolysis, heating combined with chemical hydrolysis, and sonication were employed. The effectiveness of these methods was evaluated in the context of online imaging quality through experimentation on cultivated microalgae (Chlorella vulgaris and Scenedesmus quadricauda). The chemical treatment method was found to be inappropriate for improving image acquisition. The heating pre-treatment method exhibited a drawback of prolonged cell dispersion time. Additionally, the heating combined with chemical hydrolysis method was confirmed to have the lowest dispersion effect for Chlorella vulgaris. Conversely, ultrasonication emerged as a promising technique for microalgae separation in terms of repeatability and reproducibility. This study suggests the potential for selecting optimal pre-treatment methods to effectively operate real-time online monitoring devices, paving the way for future research and applications in microalgae cultivation and imaging.

This study examined the quality characteristics and antioxidant properties of sword bean tea available in domestic markets. Each product of sword bean tea had distinct appearance characteristics. The color, pH, brownness, and turbidity of the tea varied significantly across different products, with tea bags showing higher levels of brownness and turbidity. The total polyphenol content of hot water extraction ranged from 165.13 to 517.69 mg gallic acid equivalents (GAE)/100 g sample for pod tea, 999.36 to 2,054.74 mg GAE/100 g sample for tea bag tea, and 74.62 to 275.00 mg GAE/100 g sample for grain tea, respectively. Similarly, the total flavonoid content, measured in terms of catechin equivalents (CE), ranged from 39.51 to 65.00 mg CE/100 g sample for pod tea, 86.57 to 253.63 mg CE/100 g sample for tea bag tea, and 32.94 to 38.63 mg CE/100 g sample for grain tea, for hot water extraction. The DPPH and ABTS radical scavenging activities of pod tea were 95.68 to 276.19 mg TE/100 g sample and 270.87 to 804.21 mg trolox equivalents/100 g sample, respectively, for hot water extraction. These results suggest the need to establish quality standards to ensure consistent quality of sword bean tea.

This study examined the quality characteristics of 10 different lines of native peppers collected from organic farms in Chungbuk province. The study found a strong correlation between the redness (a*) and ASTA values, which both contribute to the perceived quality of peppers. The highest values were observed in the Iyugsa line. The content of capsaicinoid and beta-carotene also showed a positive correlation, with Chilsungcho having the highest statistically significant value. While the total polyphenol content did not correlate with the other indicators, Chilsungcho again had the highest levels. The Yuwolcho line exhibited the highest ABTS radical scavenging ability, while the Eumseongcho line showed the highest DPPH radical scavenging ability. Taking into account the overall bioactivity quality, Chilsungcho had the highest values in terms of total polyphenol, beta-carotene, capsaicinoid, and redness. It also had the second highest total flavonoid content, ABTS, and DPPH radical scavenging activity, all statistically significant. Therefore, Chilsungcho can be considered an excellent choice when considering physiological activity. Furthermore, this study provides valuable information about the unique characteristics of these 10 native pepper lines, which can assist in selecting the appropriate pepper for food manufacturing and serve as a helpful resource for future research.

The objective of this study was to investigate the quality characteristics of Campbell Early grape-added traditional Korean wines (yakju) prepared with different yeasts and pretreatments. The first pretreatment (A) was prepared by crushing the grapes, the second method (B) was prepared by heating the grapes at 60~70℃ for 30 minutes, and the third method (C) was prepared by freeze-concentrating grape juice. The pH of the fermented wines ranged from 3.77 to 4.10, and the total acidity of the samples ranged from 0.32 to 0.62%. The a value (redness) ranged from –0.40 to 17.89, which was higher in Campbell Early-added samples than in the controls (grapes not added). Total polyphenol content was the highest in samples prepared by crushing or heating Campbell Early grapes with ES22, and the total flavonoid contents were the highest in samples prepared by crushing Campbell Early grapes with ES22. The anthocyanin contents were also the highest in the samples fermented by heating Campbell Early grapes. ABTS and DPPH radical scavenging activities were also the highest (84.08 and 77.56%, respectively) in samples fermented by heating Campbell Early grapes.