This research investigated how adding Sb (0.75, 1.0, 2.0 and 5.0 wt%) to as-extruded aluminum alloys affected their microstructure, mechanical properties, electric and thermal conductivity. The addition of Sb resulted in the formation of AlSb intermetallic compounds. It was observed that intermetallic compounds in the alloys were distributed homogenously in the Al matrix. As the content of Sb increased, the area fraction of intermetallic compounds increased. It can be clearly seen that the intermetallic compounds were crushed into fine particles and homogenously arrayed during the extrusion process. As the Sb content increased, the average grain size decreased remarkably from 282.6 μm (0.75 wt%) to 109.2 μm (5.0 wt%) due to dynamic recrystallization by the dispersed intermetallic compounds in the aluminum matrix during the hot extrusion. As the Sb content increased from 0.75 to 2.0 wt%, the electrical conductivity decreased from 61.0 to 59.8 % of the International Annealed Copper Standard. Also, as the Sb content increased from 0.75 to 2.0 wt%, the ultimate tensile strength did not significantly change, from 67.3 to 67.8 MPa.

The purpose of this study is to develop a pH measurement system capable of measuring the acidity of saliva to check the change in pH level in saliva during driving and to detect whether fatigue is affected. When the pH level is checked at rest and operation, and oxygen concentration is supplied additionally, it will be verified whether the fatigue is reduced. It is reported that the pH level in saliva is divided into stages from 0 to 14, and the lower the value based on step 7, the higher the fatigue, and the lower the fatigue. In particular, in enclosed vehicles, drowsiness and fatigue due to increased carbon dioxide have increased, leading to a major cause of traffic accidents. Therefore, fatigue may be detected in advance by analyzing fatigue through a change in pH level by supplying oxygen during operation. The electromotive force generated by the existing itself is a level of several mV to develop a pH measurement system, so it is developed by expanding it to a range that can be measured using a readout circuit. In the experiment, 13 male experimenters in their 20s measured pH levels in resting and driving conditions. After 20 minutes of rest, the process of inhaling oxygen for 20 minutes was repeated three times. The oxygen concentration used in the experiment was 21% oxygen and 30% oxygen concentration in the atmospheric state, and in the oxygen supply method, a triangular flask was directly connected to the subject’s nose and then oxygen was supplied. As a result of collecting and analyzing saliva after rest and operation, it was confirmed that the pH level tended to decrease in the operating state. In addition, as a result of increasing the pH level when the oxygen concentration is 30% more than 21%, it is confirmed that fatigue tends to decrease as the oxygen concentration increases. Therefore, it was possible to confirm a significant change in fatigue by analyzing the pH level of saliva through this pH measurement system. This study can be used as a fatigue test in various environments through simple pH measurement.

The The purpose of this study is to establish evaluation criteria for the purchase of electric vehicles and to present an evaluation model using quantitative scales for evaluation factors. This study was limited to the study of purchasing factors related to electric vehicles, and the spatial scope was limited to potential buyers in their 20s to 50s living in the Daejeon area. Based on the survey, the factors affecting the purchase factors (energy economics, image, performance, maintenance, price) were examined using the AHP method, and the priorities were analyzed to determine how much influence these factors have on the purchase of electric vehicles. In addition, in order to verify the logical consistency of the survey items, a consistency ratio test (c) was conducted. Through this study, priority considerations for the purchase of electric vehicles were presented, and information on future consumer interest in electric vehicles was conducted. It is judged to be able to provide an opportunity to provide various services for each layer.

The purpose of this study was to investigate the Maillard reaction–related physicochemical properties of three maize varieties (Kwangpyeongok, Sinhwangok2ho and Gangdaok) after roasting them for different times (0, 15, 25, 40, and 55 minutes). The Maillard reaction is a non-enzymatic browning reaction involving reducing sugars and amino compounds. The content of reducing sugar, the causative agent of the Maillard reaction, decreased as roasting time increased. Gangdaok showed the lowest reducing sugar content of 1.04 mg/g after 55 minutes of roasting. In the elapsed roasting time, chromaticity ‘L’ and ‘b’ values decreased. At 55 minutes of roasting, wherein the Maillard reaction occurred most actively, Gangdaok showed the lowest ‘L’ value of 56.37 and the highest ‘a’ value of 7.60. Gangdaok had superior conditions for inducing the Maillard reaction compared to other varieties, and it is consider that 'flint–type', an endosperm characteristic, may have been the influencing agent. This study detected a total of 52 types of volatile aroma compounds (VACs), of which 28 were produced after roasting. Of the total VACs detected, 2-Formyl-5-methylfuran and 2-Furancarboxaldehyde accounted for 43.8~45.5% and have been confirmed to be the major VACs present in roasted maize. Most of the correlations between the Maillard reaction–related characteristics showed high correlation coefficients.

본 연구는 전남 보성군 일림산(664m)의 관속식물상 조사를 통해 자생식물의 분포와 유용 산림자원을 발굴하는데 목적이 있다. 현장조사는 2020년 3월 31일부터 2021년 9월 22일까지 총 27차례가 수행되어, 101과 304속 444종 11아종 42변종 3품종으로 총 500분류군, 853점의 식물표본이 수집되었다. 조사된 식물을 동정한 결과, 산림청 지정 한국특산식물 16분류군, 희귀식물 7분류군, 환경부 지정 적색식물 5분류군이 확인되었다. 식물구계학적 특정종은 총 69분류군으로 Ⅰ등급 49분류군, Ⅱ 등급 7분류군, Ⅲ 등급 11분류군, Ⅳ 등급 2분류군이 확인되었다. 환경부 지정 국외반출 승인대상 생물자원 159 분류군이 목록에 포함되어 있으며, 외래식물은 총 49분류군으로 귀화율이 5.6%, 도시화지수는 7.9%이다. 외국으로부터 인위적으로 또는 자연적으로 유입되어 생태계 균형을 교란시킬 우려가 있는 생태계교란식물은 6분류군으로 조사되었다.

A field study was conducted to reduce airborne bacteria by supplying active ions to indoor spaces used by vulnerable human groups spending substantial amounts of time in places such as schools and hospitals. In an experiment conducted during school hours (8:00-15:00), the average number of airborne bacteria in classrooms was 345.53 CFU/m3 or more without active ions. However, ion supply reduced the airborne bacteria to an average of 113.23 CFU/m3, indicating an efficiency of 61.61%. As a result of tests in 33 rooms used for surgery in small and middle sized hospitals, ion supply for 2 to 4 hours reduced the average airborne bacteria concentration from 243.88 CFU/m3 to 104.34 CFU/m3, representing a 41.53% reduction. A laboratory test to confirm the ion activity has shown that the mortality rate of E. coli used as a test bacterium increased with exposure time to ions. The initial colony number of E. coli was 251 CFU, but decreased to 4 CFU after 60 minutes of exposure to active ions. Therefore, it was confirmed that the supply of active ions can contribute to the control of airborne bacteria in the indoor environment of schools, hospitals and other public facilities.

This experiment was conducted to investigate the change in the productivity of Italian ryegrass seeds according to the inter-row spacing in the southern region of the Korean Peninsula. Italian ryegrass (Lolium multiflorum Lam.) ‘Green Call’ variety was sown in Jinju, Gyeongnam in the fall of 2020 with three inter-row spacings (20, 30 and 40 cm). The experiment was arranged a randomized block design with three replications. The ryegrass was sown on October 17, 2020, and the harvest was on May 31, about 60 days from the first heading stage. There was no difference among treatments with an average of April 27th in heading stage. Plant height was significantly longer at 30 cm seeding interval and the shortest in 20 cm treatment. The length of the spike was the longest in the 40 cm seeding interval, and the number of seeds per spike was the highest in the 20cm seeding interval, but there was no significant difference among treatments. The seed yield was the highest at the 20 cm sowing interval (2,180 kg/ha), and decreased as the spacing increased. The dry matter content of seeds and straw was found to be 44.90% and 45.51% on average, and there was no significant difference among treatments. The amount of remaining straw after harvesting was found to be 7,506 kg/ha on average on DM basis, and was high at the 20 cm seeding interval. In view of the above results, it was found that it is most advantageous to sow at intervals of 20 cm when producing Italian ryegrass seeds through autumn sowing in the southern region.

한반도 지질 정보는 공공적 활용을 위한 기초 지식의 토대를 제공하며 역사 과학으로서 지질학의 본성을 배울 수 있는 계기를 마련하므로 과학교육 측면에서 중요성이 크다. 특히 한반도에서 지구조 활동이 활발했던 중생대는 한반 도 지사를 이해하기 위해 매우 중요한 시기이다. 본 연구의 목적은 2015 개정 교육과정에 기반한 지구과학II 교과서의 ‘한반도의 지질’ 단원에서 중생대의 지질과 관련된 내용의 신뢰성과 일관성을 분석하는 것이다. 분석 대상은 지구과학II 교과서 4종이고, 분석 범위는 중생대의 퇴적층, 지각 변동 및 화강암류이다. 분석 항목은 분석 범위와 관련된 용어, 시 기, 암석 분포 지역이며, 분석 항목별로 교과서 내·교과서 간 일치 여부 및 과학 지식과 교과서 내용의 일치 여부를 분석하였다. 분석 결과, 중생대 지질 관련 용어, 시기, 암석 분포 지역 측면에서 각각 다양한 불일치 사례가 확인되었으며, 불일치 사례를 중심으로 개선 방안을 논하였다. 한반도 지질 교육의 목표를 달성하기 위해 과학계와 교육계의 협업을 통해 최신 과학 지식과 정합한 교육 자료가 개발될 필요성을 강조하였다.

Vegetation is the basis for biodiversity conservation and sustainable development. In the Environmental Impact Assessment (EIA), which is the most direct and efficient policy measure to prevent degradation of nature, vegetation-related assessment has limitations as it is not based on quantitative and scientific methods. In addition, it focuses on the presence of protected species; hence, it does not take into account the role of vegetation as a habitat on a wide-area scale. As a way to overcome these limitations, this study aims to contribute to the quantification and advancement of future EIA on vegetation. Through the review of previous studies, core areas, connectivity, and vegetation condition were derived as the items to be dealt within the macroscopic aspect of vegetation impact assessment. Each item was spatially constructed using land cover maps and satellite imageries, and time series change analysis was performed. As a result, it was found that vegetation has been continuously deteriorating due to development in all aspects, and in particular, development adversely affects not only the inside of the project site but also the surrounding area. Although this study suggested the direction for improvement of the EIA in the vegetation sector based on data analysis, a more specific methodology needs to be established in order to apply it to the actual EIA process. By actively utilizing various environmental spatial data, the impact of the development on the natural ecosystem can be minimized.

본 연구에서는 기능성 식의약품 소재로써 갈색 느티만 가닥버섯(Hypsizygus marmoreus)의 이용 가능성을 조사하기 위해 갈색 느티만가닥버섯의 부위별, 추출 용매별 항산화 활성을 조사하였다. 열수 추출물 갓과 대의 총 폴리페놀 함량은 17.15±0.19 mg GAE/g과 7.37±0.16 mg GAE/g이었으며 에탄올 추출물 갓과 대의 총 폴리페놀 함 량은 각각 10.23±0.14 mg GAE/g과 3.76.±0.19 mg GAE/g 으로 에탄올 추출물에 비해 열수 추출물의 폴리페놀 함량이 높게 나타났고 대에 비해 갓의 폴리페놀 함량이 높게 나타났다. 또한 갈색 느티만가닥버섯 추출물의 DPPH, ABTS, ORAC 지수, 환원력도 10 mg/ml의 농도에서 에탄올 추출물에 비해 열수 추출물에서 높게 나타났고 대에 비해 갓에서 높게 나타났으며 흰색 느티만가닥버섯에 비해 갈색 느티만가닥버섯의 총 폴리페놀 함량, DPPH, ORAC 지수, 환원력이 높은 것으로 나타났다. 추출물의 세포독성 은 WST-1 assay (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H- 5–tetrazolio]-1,3-benzene disulphonate)를 이용하여 열수 추출물의 처리 농도에 따른 대식세포주 RAW 264.7의 세포 생존율로 확인하였으며 갈색 느티만가닥버섯 열수 추출물 처리구에서 대식세포주 RAW 264.7의 세포 생존율이 증가하였기 때문에 세포독성은 없는 것으로 판단된다. 이상의 결과를 종합하면, 느티만가닥버섯은 품종에 따라 항산화 활성에 차이가 있고, 갈색 느티만가닥버섯은 다른 버섯보다 항산화 활성이 높기 때문에 기능성 식의약품 소재로서 이용 가능성이 있다고 판단된다.

본 연구는 고온기 원예작물의 안정 생산을 위해 대형 단동하우스 ‘사계절하우스’를 파프리카 재배에 활용 시 시설 내부 기상 환경 및 파프리카 품종별 생육, 수량, 품질 등을 분석하고 근권냉방 효과 등을 구명하여 파프리카 재배환경 조건을 최적화 하기 위한 기초자료로 사용하고자 수행하였다. 정식 후부터 재배 종료 시점(2020년 5－11월)까지 시설내 평균 적산광량은 12.7MJ·m -2 d -1로, 온실외부의 평균 광량인 14.1MJ·m -2 d -1의 90% 수준으로 나타났다. 일 년중 가장 기온이 높은 7－8월의 온실내 24시간 평균온도는 외기보다 3.04℃ 낮았고, 장마가 끝난 8월 12일 이후에는 평균 4.07℃ 낮게 나타났다. 시설 내 포그 냉방 가동(6월 13일) 이전 일평균 상대습도는 최저 40% (주간 20%) 수준까지 떨어져 작물재배에 적합하지 않은 상태였으나 포그를 가동한 이후 주간 상대습도는 70－85% 수준으로 증가된 것으로 나타났다. 평균 수분부족분(humidity deficit)은 포그 공급전에는 최고 12.7g/m 3 까지 상승하여 매우 건조한 조건이었으나, 포그 공급 후 고온기(7－8월)에 평 균 3.7g/m 3으로 감소하였고, 저온기(10－11월)로 갈수록 다시 증가되는 경향이었다. 주간 잔존 CO2 농도는 전체 재배기 간동안 평균 707ppm으로 나타났다. ’20년 7월 27일부터 11월 23일까지 수확한 파프리카의 품종별 상품수량(kg/10a)은 주황색 품종 ‘DSP-7054’과 황색 품종 ‘Allrounder’이 각각 14,255kg/10a와 14,161kg/10a로 다른 품종에 비해 높았고, 다음으로 주황색 ‘K-Gloria orange’, 황색 ‘Volante’, 적색 ‘Nagano’ 품종 순으로 나타났다. 사계절하우스에서 고온기(8 월)에 생산된 대과종 파프리카의 품종별 과실품질 특성을 조사한 결과, 과고, 과폭, 과실당도, 과육두께에서 품종 간 유의성이 인정되었다. 당도는 주황색 품종인 ‘DSP-7054’와 ‘Naarangi’에서 높게 나타났고, 과육두께는 황색과 주황색 품종인 ‘K-Gloria orange’와 ‘Allrounder’에서 높게 나타났다. 근권 냉방처리 기간 동안 배지내 일평균 온도는 20.7℃로 나타났고, 근권 난방처리 기간 동안 배지내 일평균 온도는 23. 4℃로 나타났다. 근권부 냉난방 처리를 통해 상품수량은 무처리구에 비해 비해 ‘Nagano’ 16.5%, ‘Allrounder’ 1.3%, ‘Naarangi’ 20.2%, 및 ‘Raon red’ 17.3% 증가하였고, 품종 전체로는 16.1% 증가하였다. 근권 냉난방처리에 의해 과실의 경도는 4개 품종 평균 5.7% 증가하였으나 다른 품질 지표에서는 유의성있는 차이가 나타나지 않았다.