This study evaluated the suitability of using Wickerhamomyces anomalus A1-5 isolated from solid grain fermentation broth for winemaking by comparing the quality and functionality of Campbell Early wine produced with single and mixed inoculations. The pH ranged from 3.43 to 3.68, with the highest value in treatment B. Soluble solids ranged from 5.0 to 7.7 °Brix. Total acidity was measured at 0.42% to 0.47%. Color analysis indicated a significant decrease in lightness with an increase in redness across all treatment groups compared to the control. Among aroma compounds, 8 alcohols, 6 esters, 3 acids, and 11 other compounds were identified, with the control having the highest alcohol content and treatment D having the highest ester content. Tannin and total polyphenol contents ranged from 46.46 mg% to 95.92 mg% and from 87.66 mg% to 147.21 mg%, respectively. Antioxidant activities measured by DPPH and ABTS assays ranged from 33.84% to 69.02% and from 42.43% to 89.18%, respectively, with treatment B exhibiting the highest activities. These results suggest that W. anomalus A1-5 may positively influence the quality and functionality of Campbell Early wine, presenting potential as a novel yeast strain for winemaking.
In this study, copper oxide, manganese oxide and zeolite, clays containing catalysts were prepared to remove hydrogen sulfide emitted in odor of industry. In order to change the heat treatment temperature, a catalyst was prepared 100 degrees from 600 degrees to 1,000 degrees. GC-MS was used to confirm the hydrogen sulfide removal performance. Although the removal performance produced at 600 degrees was maintained by and large, the removal performance decreased as the temperature increased. In particular, the catalyst manufactured at 900 and 1000 degrees had low removal performance. To find out the cause of the decrease in removal performance, the analytical devices XRD, BET, XRF were used. In order to confirm the properties of the catalyst before and after adsorption, SEM-EDS and CS were used. As a result of analyzing the Cu-Mn catalyst, it was confirmed that the material was adsorbed on the surface. To confirm the adsorbent material, SEM-Mapping was employed. And it was verified that the sulfur was adsorbed. Measuring the SEM-EDS 3Point, it was confirmed to be about 25.09%. Another test method CS analyzer (Carbon/Sulfur Detector) was also deployed. As a result of the test, sulfur was confirmed to be about 27.2%. So comparing the two sets of data, it was verified that sulfur was adsorbed on the surface.
Wheat (Triticum aestivum L.), a significant cereal crop from the Gramineae family, serves as a vital source of protein, essential minerals, B-group vitamins, and dietary fiber. However, its productivity is often hindered by issues such as poor seed germination, which can adversely affect yield and crop quality. This study investigated the effects of different silicon concentrations and priming durations on wheat germination and seedling growth. Analysis of variance revealed that silicon treatment significantly influenced key parameters of germination and growth, including germination percentage (GP), germination index (GI), vigor index (VI), radicle length (RL), plumule length (PL), and seedling dry weight (SDW). Priming with silicon at a concentration of 1 mM resulted in notable improvements, increasing GP, GI, VI, RL, and PL by 10.6%, 65.5%, 29.4%, 18.6%, and 28.6%, respectively, after 6 hours of priming. Certain germination traits demonstrated strong positive correlations, particularly GP and GI (r = 0.96) and VI and RL (r = 0.94), after 4 hours of priming. These improvements in seed germination and seedling development may result from enhanced water uptake, stimulated cell division, and increased hydrolytic enzyme activity, which facilitate the mobilization of seed reserves and accelerate the growth of embryonic tissues.
As digital transformation accelerates, platform business has become a core business model in modern society. Platform business has a network effect where the winner takes all. For this reason, it is crucial for a company's pricing policy to attract as many customers as possible in the early stages of business. Telecommunication service companies are experiencing stagnant growth due to the saturation of the smartphone market and intensifying competition in rates, but the burden of maintaining communication networks is increasing due to the rapid increase in traffic caused by domestic and foreign CSPs. This study aims to understand the dynamic characteristics of the telecommunications market by focusing on pricing policy. To this end, we analyzed how ISPs, CSPs, and consumers react to changes in pricing policy based on the prisoner's dilemma theory. The analysis of the dynamic characteristics of the market was conducted through simulation using the Agent-Based Model.
본 연구는 생물음향 모니터링 기법을 이용하여 나그네새인 울새의 한국 도래 특성을 5개년(2019~2023년)에 걸쳐 확인하는데 목적이 있다. 연구대상종은 울새이고, 연구대상지는 국립공원 24개소, 도립공원 1개소, 람사르습지 6개소, 기타 4개소로 총 35개소였다. 데이터 수집 기간은 2019년 1월부터 2023년 12월이며, 분석 기간은 매년 4~5월이었다. 주요 연구결과는 다음과 같다. 첫 번째, 울새 번식울음은 5개년 공통적으로 06시에 가장 빈도가 높았으며, 20시부터 야간, 새벽까지는 울음 활동이 확인되지 않는 시간적 특성이 나타났다. 시기적으로는 5월 1일부터 5월 19일까지 번식울 음이 확인되었고, 2019년에는 5월 8일, 9일, 2020년에는 5월 5일, 13일, 2021년에는 5월 11일, 2022년에는 5월 9일, 10일, 2023년에는 5월 4일에 번식울음 빈도가 가장 높았다. 두 번째, 울새 번식울음이 탐지된 지역은 오대산국립공원 월정사숲, 북한산국립공원 진관동습지, 주왕산국립공원 주산지, 창녕 우포늪, 제주 동백동산 등 14개소였다. 5년 동안 공통적으로 탐지된 곳은 계룡산국립공원 용동저수지, 태안 두웅습지, 고창 운곡습지, 서울 남산이었다. 세 번째, 울새 번식울음 기간 특성을 연도별-대상지별로 확인해본 결과, 2019년에는 5월 5일부터 5월 19일까지, 2020년에는 5월 3일부터 5월 17일까지, 2021년에는 5월 1일부터 5월 13일까지, 2022년에는 5월 3일부터 5월 15일까지, 2023년에는 5월 3일부터 5월 17일까지였다. 번식울음의 탐지 일수가 가장 많은 곳은 5개년 공통적으로 서울 남산이었다. 네 번째, 울새 번식울음이 탐지된 날의 연도별 평균에 차이가 있었고(p<0.001), 사후검정 결과, 차이가 발생한 시점은 2020년과 2021년으로 나타났다. 본 연구는 생물음향 모니터링 기법을 활용하여 소형 나그네새인 울새의 도래 특성을 정밀하게 확인하였고, 향후 기후변화와의 관련성과 보호지역 관리를 위한 기초자료를 제공하였다는 점에서 의의가 있다.
Evaluating the performance of asphalt concrete using CT scanning has become an essential area of research due to its potential to revolutionize the way we assess road materials. Traditional methods often require destructive sampling, which can damage infrastructure and offer limited insight into the material's internal structure. In contrast, CT scanning provides a non-destructive, highly detailed analysis of asphalt's internal features, such as air voids, aggregate distribution, and binder coverage, all of which are critical to its durability and performance. Additionally, the ability to create 3D models from CT scans allows for deeper insights into factors like void connectivity and aggregate bonding, which directly affect the lifespan of pavements. By combining CT imaging with advanced data processing techniques, such as deep learning, this research offers more accurate and reliable methods for optimizing asphalt mix designs, ultimately leading to longer-lasting roads, reduced maintenance costs, and more sustainable construction practices.
Organic-inorganic hybrid coating films have been used to increase the transmittance and enhance the physical properties of plastic substrates. Sol-gel organic-inorganic thin films were fabricated on polymethylmethacrylate (PMMA) substrates using a dip coater. Metal alkoxide precursor tetraethylsilicate (TEOS) and alkoxy silanes including decyltrimethoxysilane (DTMS), 3-glycidoxypropyltrimethoxysilane (GPTMS), phenyltrimethoxysilane (PTMS), 3-(trimethoxysilyl)propyl methacrylate (TMSPM) and vinyltrimethoxysilane (VTMS) were used to synthesize sol-gel hybrid coating solutions. Sol-gel synthesis was confirmed by the results of FT-IR. Cross-linking of the Si-O-Si network during synthesis of the sol-gel reaction was confirmed. The effects of each alkoxy silane on the coating film properties were investigated. All of the organicinorganic hybrid coatings showed improved transmittance of over 90 %. The surface hardness of all coating films on the PMMA substrate was measured to be 4H or higher and the average thickness of the coating films was measured to be about 500 nm. Notably, the TEOS/DTMS coating film showed excellent hydrophobic properties, of about 97°.
Volatile organic compounds (VOCs) can adversely affect human and plant health by generating secondary pollutants such as ozone and fine particulate matter, through photochemical reactions, necessitating systematic management. This study investigated the distribution characteristics of gaseous VOCs in ambient air, with a focus on interpreting data from a photochemical pollution perspective. This paper analyzed the presence and concentration distribution of VOCs in industrial areas, identifying toluene, m-xylene, p-xylene, and n-octane as the most frequently detected components. Particularly, toluene was found to significantly contribute to the formation of ozone and fine particulate matter, highlighting the need for stricter regulation of this compound. Although n-octane and styrene were present in relatively low concentrations overall, their significant contributions to ozone generation and secondary organic aerosol formation, respectively, emphasize their importance in air pollution management.
In order to overcome the limitations of linear vibration energy harvesters and those using mechanical plucking, magnetic plucking vibration energy harvesters (MVEs) have garnered significant interest. This paper presents parametric studies aimed at proposing design guidelines for MVEs and compares two magnetic force models that describe interactions between two permanent magnets. A mathematical model describing the energy harvester is employed, followed by the introduction of two magnetic force models: an analytic model and an inverse square model. Subsequently, numerical simulations are conducted to investigate dynamic characteristics of MVEs, analyzing results in terms of tip displacement, voltage output, and harvested energy. Parametric studies vary the distance between magnets, the speed of the external magnet, and the beam shape. Results indicate that reducing the distance between magnets enhances energy harvesting effectiveness. An optimal velocity for the external magnet is observed, and studies on beam shape suggest greater energy harvesting when the shape favors deflection.
As the demand for electric vehicles increases, the stability of batteries has become one of the most significant issues. The battery housing, which protects the battery from external stimuli such as vibration, shock, and heat, is the crucial element in resolving safety problems. Conventional metal battery housings are being converted into polymer composites due to their lightweight and improved corrosion resistance to moisture. The transition to polymer composites requires high mechanical strength, electrical insulation, and thermal stability. In this paper, we proposes a high-strength nanocomposite made by infiltrating epoxy into a 3D aligned h-BN structure. The developed 3D aligned h-BN/epoxy composite not only exhibits a high compressive strength (108 MPa) but also demonstrates excellent electrical insulation and thermal stability, with a stable electrical resistivity at 200 °C and a low thermal expansion coefficient (11.46×ppm/°C), respectively.
In this study, chicken fry was made using batter prepared from a frying pre-mix that replaced wheat flour (WF) with floury rice powder (FRP) at ratios of 0% (control group), 25% (FRP-25 group), 50% (FRP-50 group), 75% (FRP-75 group), and 100% (FRP-100 group). The physicochemical and acceptability of the finished chicken fry were assessed to provide basic data for product development studies using FRP. The experimental groups that replaced WF with FRP showed higher water binding capacity and lower fat binding capacity than the control group (p<0.05). The viscosity of the batter decreased significantly as the proportion of FRP increased (p<0.05). The pick-up rate measurement results showed significantly lower values in experimental groups compared to the control group (p<0.05). The color measurement results of the chicken fry showed that as the substitution ratio of FRP to WF increased, lightness decreased, and redness increased (p<0.05). The browning index also showed a significant increase as the substitution ratio of FRP increased. The acceptance test results showed that the FRP-100 experimental group was significantly higher in all acceptability characteristics than the control group (p<0.05).
본 연구는 폴리케톤(PK) 지지체를 이용한 유기용매 역삼투(OSRO) 분리막 제조를 목적으로 하였다. 비용매 유도 상분리 방법(NIPS)을 통해 PK 지지체를 제작하였고, PK 지지체 위에 polyamide layer를 계면 중합하여 thin-film composite (TFC) 형태로 OSRO 분리막을 완성하였다. 이후 OSRO 분리막의 표면과 단면 구조 및 표면의 화학적 구조를 분석하였고 수 투과도와 염 제거율은 각각 약 1.28 LMH/bar와 99.0%의 결과를 얻었다. 또한 OSRO 분리막의 polyamide layer는 유기용매 침지 1일 동안 매우 안정적이었고, 단일 유기용매 투과도 경향성은 유기용매 나노여과(OSN) 분리막의 투과도 모델과 일치하 였다. OSRO 분리막의 MWCO는 MeOH 상에서 240 g/mol이었다. OSRO 분리막의 MeOH-toluene 혼합용액에 대한 투과도 와 separation factor는 상용 OSN 분리막보다 각각 200%와 60%의 높은 결과를 얻었다.
우리나라의 도농복합시는 1995년 지방자치제도가 시행되면서 등장한 도시 유형으로, 도시와 농촌의 균형발전을 목적으로 시행되고 있다. 본 연구는 우리나라 54개 도농복합시를 대상으로 인구, 사회, 경제, 인프라의 4개 영역, 14개 지표로 구성된 도시역량 지표를 종합지수화하여 2010년과 2020년의 도농복합시 도시역량의 공간 분포 패턴 및 변화를 실증적으로 탐색한다. 주요 연구 결과는 다음과 같다. 첫째, 인구가 많은 도시일수록 도시역량이 높은 경향이 나타났다. 둘째, 2010년부터 2020년까지 전반적으로 도농복합시 도시역량 지수의 범위가 축소되는 경향이 나타났다. 셋째, 세 집단으로 유형화한 도농복합시의 도시역량 의 차이를 비교한 결과, 유의미한 차이가 확인되었다.
The purpose of this study is to analyze the correlation between ecotoxicity and water quality items using Daphnia magna in public sewage treatment plant process and to obtain operational data to control ecotoxicity through research on removal efficiency. The average value of ecotoxicity was 1.39 TU in the influent, 1.50 TU in the grit chamber, and 0.84 TU in the primary settling tank and it was found that most organic matters, nitrogen, and phosphorus were removed through biological treatment in the bioreactor. Using Pearson’s correlation analysis, the positive correlation was confirmed in the order of ecotoxicity and water quality items TOC, BOD, T-N, NH3-N, SS, EC, and Cu. As a result of conducting a multilinear regression analysis with items representing positive correlation as independent variables, the regression model was found to be statistically significant, and the explanatory power of the regression model was about 81.6%. TOC was found to have a significant effect on ecotoxicity with B=0.009 (p<.001) and Cu with B=16.670 (p<.001), and since the B sign is positive (+), an increase of 1 in TOC increases the value of ecotoxicity by 0.009 and an increase in Cu by 1 increases the value of ecotoxicity by 16.670. TOC (β=0.789, p<.001) and Cu (β=0.209, p<.001) were found to have a significant positive effect on ecotoxicity. TOC and Cu have a great effect on ecotoxicity in the sewage treatment plant process, and it is judged that TOC and Cu should be considered preferentially and controlled in order to efficiently control ecotoxicity.
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.
Daemadeung, located in the estuary of the Nakdong River, is formed by sand dunes and possesses well-developed intertidal flats. This study aimed to investigate the habitat of benthic microalgae, photosynthetic pigments, and photosynthetic efficiency in the intertidal flats of Daemadeung from January to December 2011. The inorganic nitrogen content in the sediment pore water was primarily composed of ammonium, while nitrate+nitrite was dominant in the upper layer water. The concentration of chlorophyll a and fucoxanthin in the sediment surface was significantly higher than the mean of all the sediment layer. The average Fv/Fm of benthic microalgae during the entire survey period was 0.52±0.03, with the highest value (0.61±0.08) observed in February. The rETRmax showed a seasonal trend, being high from spring to early autumn (April to October) and low from winter to early spring (January to March, November, December), with the highest value (153.05±2.30 μmol electrons m-2 s-1) in July and the lowest (38.49±5.17 μmol electrons m-2 s-1) in January. The average Fv/Fm of diurnal microalgae was 0.48±0.03, with the highest value (0.61±0.08) observed at noon. The rETRmax showed a highest peak at noon (54.24±11.35 μmol electrons m-2 s-1) and reached its lowest point at 16:00 (26.17±4.75 μmol electrons m-2 s-1). These findings suggest that the productivity of benthic microalgae varies significantly depending on the survey time and sediment depth. Therefore, to quantify the productivity of benthic microalgae using Diving-PAM, surveys should be conducted based on tidal conditions, and simultaneous pigment analysis of sediment layers should also be performed.
반응성 에시드 클로라이드인 트리멜리틱 안하이드라이드 클로라이드를 이용한 2-에티닐피리딘의 무촉매중 합을 통하여 트리멜리틱 부분을 측쇄로 갖는 이온성 공액구조 고분자를 합성하였다. 2-에티닐피리딘과 트리멜리틱 안하이드라이드 클로라이드를 1:1 몰비로 DMF 용매에서 반응시킨 결과 해당 공액구조 고분자를 높은 수율로 합성 할 수 있었다. 첫 번째 반응 단계에서 만들어진 단량체인 N-치환-2-에티닐피리디늄 염은 별도의 촉매 사용없이도 중합반응이 잘 진행되었다. NMR, IR, UV-visible 등의 분광분석기를 사용하여 합성 고분자의 구조를 분석한 결과 설계한 치환기를 갖는 공액구조 고분자가 합성되었음을 확인할 수 있었다. 합성 고분자의 전기-광학적 특성과 전기 화학적 특성을 측정하였다. 본 고분자는 자외선 영역뿐만 아니라 가시광선 영역에서 500 nm까지 넓은 흡수 피크 를 보였으며 PL 최대값은 539 nm에서 나타났다.