Estuary is important in terms of biodiversity because it has the characteristics of transition waters, created by the mixing of fresh- and seawater. The estuarine water circulation provides a variety of habitats with different environments by inducing gradients in the chemical and physical environment, such as water quality and river bed structure, which are ultimately the main factors influencing biological community composition. If the water circulation is interrupted, the loss of brackish areas and the interception of migration of biological communities will lead to changes in the spatial distribution of biodiversity. In this study, among the sites covered by the Estuary Aquatic Ecosystem Health Assessment, we selected study sites where changes in biodiversity can be assessed by spatial gradient from the upper reaches of the river to the lower estuarine area. The α-, γ- and β-diversity of diatom, benthic macroinvertebrates, and fish communities were calculated, and they were divided into open and closed estuary data and compared to determine the trends in biodiversity variation due to estuarine circulation. As results, all communities showed higher γ-diversity at open estuary sites. The benthic macroinvertebrate community showed a clear difference between open and closed estuaries in β-diversity, consequently the estuarine transects were considered as a factor that decreases spatial heterogeneity of their diversity among sites. The biodiversity trends analyzed in this study will be used to identify estuaries with low γ- and β-diversity by community, providing a useful resource for further mornitoring and management to maintain estuarine health.

Fungi have been known as an irritant or causal agent of asthma. Thus, information on their concentration and diversity in indoor air of asthmatic patient’s houses is valuable for the management of these micro-organisms. The present study was performed to investigate fungal concentration and diversity in indoor air of resident spaces in two adult patient’s houses in winter. Air samples were collected in February of 2018 from living rooms and bedrooms of two asthma patients’ houses located in two different places in Incheon city using an impaction method. The average concentrations of airborne fungi did not exceed the 500 CFU/m3 level which is recommended by the Enforcement Managements of the Indoor Air Quality, Ministry of Environment, Korea. A total of four genera and 23 species were identified based on morphological and molecular methods. Aspergillus and Penicillium were two major genera. Aspergillus pseudoglaucus and Penicillium citrinum were commonly found between the two patient’s houses. Among the identified fungi, three species, Aspergillus venenatus, Penicillium jamesonlandense, and Penicillium salami were found to be unrecorded species in Korea. The morphological and molecular characteristics of these three unrecorded species were described. Since these species produce spores well and a lot, they are considered to be a species that needs management. This study provides basic information on the fungi for indoor air quality management in the living spaces of asthma patients in winter in Korea.

Fish assemblage of total 325 of Korean peninsula estuaries were surveyed to analyze the characteristics of community structure and diversity by sea areas for three years from 2016 to 2018. The scale (stream width) of Korean estuaries were various (14~3,356 m), and 68.9% of all estuaries showed salinity of less than 2 psu. Total 149 species classified into 52 families of fish were identified, and the dominant and sub-dominant species were Tribolodon hakonensis (relative abundance, RA, 12.5%) and Mugil cephalus (RA, 9.5%), respectively. The estuary of the Korean Peninsula had different physical and chemical habitat environments depending on the sea area, and accordingly, fish community structure also showed statistically significant differences (PERMANOVA, Pseudo-F=26.69, P=0.001). In addition, the NMDS (nonmetric multidimensional scaling) results showed the patterns that indicating fish community difference by sea areas, even though low community similarity within sea area (SIMPER, 21.79~26.39%). The estuaries of east sea areas were distinguished from the others in the aspects of which, the higher importance of migratory fishes and endangered species, and that of brackish species were characterized at south sea estuaries. However, the estuaries of west sea showed higher importance of species that have a relation with freshwater (primary freshwater species, exotic species), which is the result that associating with the lower salinity of west sea estuaries because of the high ratio of closed estuaries (78.2%). The SIMPER analysis, scoring the contribution rates of species to community similarity, also showed results corresponding to the tendency of different fish community structures according to each sea area. So far, In Korea, most studies on fish communities in estuaries have been conducted in a single estuary unit, which made it difficult to understand the characteristics of estuaries at the national level, which are prerequisite for policy establishment. In present study, we are providing fish community structure characteristics of Korean estuaries in a national scale, including diversity index, habitat salinity ranges of major species, distribution of migratory species. We are expecting that our results could be utilized as baseline information for establishing management policies or further study of Korean estuaries.

‘Buddybell’ is a promising crabapple variety developed as a pollinizer at the Apple Research Institute, National Institute of Horticultural and Herbal Science, Rural Development Administration, Korea, in 2019. This variety was selected from seedlings obtained by natural crossing of Malus baccata. It was collected from Mt. Jeombong, Inje-gun, and Gangwon-do. Line selections were conducted from 2009 to 2016, and characteristic evaluations were performed from 2009 to 2010. Tree vigor and tree form of ‘Buddybell’ were medium and upright, respectively. The first flowering time was early, around April 16, and the flowering period was as long as 14 days. The flowers of ‘Buddybell’ were pink in the balloon stage and white in full bloom. ‘Buddybell’ has a high fruit setting rate with major apple varieties(‘Fuji’, ‘Hongro’, and ‘Tsugaru’). The amount of pollen weight per 1,000 inflorescence of ‘Buddybell’ was 2.5 times higher than that of 'Maypole'; hence, it is highly useful as a pollinizer in apple orchard. ‘Buddybell’ was officially applied for variety protection on Korea Seed & Variety Service in 2020 (Application no.2020-237).

In this study, we learned about the effects of indoor radon concentration reduction associated with the operation of a mechanical ventilation system at an apartment house. The experimental parameters were mainly the indoor radon level and air change rate, which were controlled by the amount of emissions released and fan motor speed. Even at the high level of radon diffused in an apartment house, indoor radon concentrations converged to the Korean national guideline level within 3 to 4 hours when the air was ventilated at 0.5 ACH and 0.7 ACH. In the case of 0.3 ACH, however, where the degree of ventilation was insufficient compared to the legal air change rate, the high concentration indoor radon could not be sufficiently removed even if the mechanical ventilation system was operated for more than 14 hours continuously. When the indoor radon level was high, the reduction rate was 34.3% for 0.3 ACH, 70.4% for 0.5 ACH, and 69.7% for 0.7 ACH at 6 hours-operation, while at the medium-level, indoor radon can be reduced by 46.2% (0.3 ACH) to 73.2% (0.7 ACH). Depending on the indoor concentration range, it may be required to secure a ventilation rate of 0.5 ACH or more at all times. In addition, in apartment houses with excellent airtight performance, even if indoor radon is at a level similar to the national guideline, it is difficult to expect a reduction in the concentration due to natural decay. Therefore, it is desirable to lower the indoor concentrations as much as possible.

This study was performed to evaluate the effect of pork belly thickness on physicochemical and sensory characteristics after pan frying. Pork belly with three different thickness (5, 10, 20 mm) from three different parts (A:thoracic vertebrae no. 5-9, B:thoracic vertebrae 10-14, C:lumbar vertebrae 1-6) was pan grilled with electronic grill until it reached an internal temperature of 71℃. Cooking loss, shear force, sensory characteristics, volatile compounds of cooked pork belly were determined. Electric nose analysis was performed to support descriptive analysis and consumer sensory analysis. The cooking loss of pork belly with 20 mm thickness from all positions was significantly low (p<0.05). Shear force increased with increase in thickness (p<0.05). Electric nose identified major seven volatile compounds such as acetonitrile, (Z)-4-heptenal, 2-octanol, linalool, carbon disulfide, methylcyclohexane, n-nonanal to discriminate those samples. The part of pork belly significantly affected the intensity of volatile compounds rather than thickness. In discriminate analysis, the overall acceptability of pork belly (A and B parts) with 20 mm thickness was higher than that of pork belly with 5 mm thickness. In addition, the overall acceptability by consumers for pork belly with 20 mm thickness from A, B, and C parts was higher than the overall acceptability for pork belly with 5 mm thickness. This preliminary study suggests that it is more desirable to use pork belly with 20 mm thickness from part A when cooking on a pan gril compared with pork belly of 10 mm or 20 mm thickness from part B or C in the meat markets and restaurant.

소면적 약용작물인 율무의 주산지인 연천에서 조명나방의 발생 양상을 조사하고, 이를 기반으로 5종의 살충제와 3종의 유기농업 자재에 대 한 포장 방제효과를 검정하였다. 조명나방의 성충은 5월부터 발생이 시작되어 10월 하순까지 총 3세대를 경과하였다. 포장시험 결과, 5종의 살충 제인 novaluron, lufenuron, spinetoram, cyclaniliprole, flufenoxuron과 3종의 유기농업 자재인 CCBP (gosam extracts 90%), LT (neem extracts 60%), JT (citronella oil 30 + derris extracts 20 + cinnamon extracts 10%)는 율무에 발생하는 조명나방에 대하여 2 지역 모두에서 높은 방제효과를 보였으며, 2배량에서도 약해가 없어 율무 전용 살충제로써 이용이 가능할 것으로 생각된다.

본 연구의 목적은 예비 지구과학교사들이 학생에 의해 구성된 기후변화 모델을 평가하는 기준을 탐색하는 것이 다. 대도시 소재 대학 지구과학교육과 전공 수업에서 3주간 모델링 기반 과학 학습에 대한 강의를 수강한 예비 지구과 학교사 25명이 연구에 참여하였다. 예비 지구과학교사들이 작성한 고등학생들이 구성한 7개의 기후변화 모델을 평가하 는 보고서와 사후 인터뷰 자료를 수집하여 기후변화 모델 평가 기준을 귀납적으로 범주화하였다. 연구 결과 예비 지구 과학교사들이 기후변화 모델을 평가할 때 다양한 인식론적 기준과 의사소통 기준을 동원하였음을 확인하였다. 연구 결 과를 바탕으로 모델링 기반 기후변화 학습에 대한 시사점을 도출하였다.

This study aimed to evaluate the changes in the content of functional components and antioxidant activity of rice and barley according to the milling process used. A considerable amount of γ-oryzanol was observed in unmilled rice and barley. However, γ-oryzanol was not detected in the rice and barley after the milling process. The highest content of γ-aminobutyric acid (GABA) was observed in the unmilled Keunalbori-1-ho barley. The contents of biotin in all samples also decreased in the milled grains compared to the unmilled grains. The highest content of total polyphenols and flavonoids was observed in the Heuksujeongchal barley, and the highest radical scavenging activity was also found in this grain. The milling process led to a decrease in the content of functional components, including γ-oryzanol, GABA, biotin, polyphenols, and flavonoids in both rice and barley. These results may be useful in the development of processed foods using cereal grains.

최근 동아시아 지역에서 인위적 배출량의 감소에도 불구하고, 봄철에 한국에서는 잦은 연무 사례가 발생하고 있 다. 북동 태평양에서 자주 발생하는 대기 블로킹은 지구 규모 대기 변동과 동아시아 지역의 서풍 기류를 정체시키기도 한다. 2019년 3월 동아시아 지역의 온난하고 정체적인 종관 기상 특성이 알래스카 대기 블로킹이 발생한 6-7일 후에 일어나고 있었다. 특히, 2019년 3월 18-24일에 발생한 알래스카 대기 블로킹은 3월 25-28일 동안 한국에서 일평균 미 세먼지(particulate matter; PM10) 질량농도가 50 μg m−3을 넘는 고농도 PM10 연무 사례가 발생하는 데 영향을 미치고 있 었다. 한편, WRF-Chem 모델을 활용하여 한국의 고농도 PM10 연무 사례에 대한 인위적 배출의 장거리 수송 기여도는 30-40%를 나타내고 있었다. PM10 에어로졸 구성 성분인 황산염, 질산염, 암모늄, 블랙 카본, 유기 탄소, 기타 무기물의 장거리 수송 기여도는 각각 10-15, 20-25, 5-10, 5-10, 5-10, 15-20%를 나타내었다. 질소 산화물이 온난하고 정체적인 대기에서 암모늄과의 광화학 반응으로 형성된 질산암모늄은 한국의 고농도 PM10 연무 사례에 대한 장거리 수송 기여도 가 PM10 에어로졸 중 가장 큰 비중을 나타내고 있었다.

Tungsten carbide is widely used in carbide tools. However, its production process generates a significant number of end-of-life products and by-products. Therefore, it is necessary to develop efficient recycling methods and investigate the remanufacturing of tungsten carbide using recycled materials. Herein, we have recovered 99.9% of the tungsten in cemented carbide hard scrap as tungsten oxide via an alkali leaching process. Subsequently, using the recovered tungsten oxide as a starting material, tungsten carbide has been produced by employing a self-propagating high-temperature synthesis (SHS) method. SHS is advantageous as it reduces the reaction time and is energy-efficient. Tungsten carbide with a carbon content of 6.18 wt % and a particle size of 116 nm has been successfully synthesized by optimizing the SHS process parameters, pulverization, and mixing. In this study, a series of processes for the highefficiency recycling and quality improvement of tungsten-based materials have been developed.

This study investigated the effect of bactocease, as a natural preservative, on the microbial growth and quality of fried fish paste during storage. To select the optimal concentration of bactocease, the inhibition effect of its different treatment concentrations (0.2, 0.4, and 0.8%) on total aerobic bacteria in fish paste dough during 5 days of storage was examined. The sample treated with 0.4% bactocease showed a 1.21 log reduction in microorganisms compared with that of the control. This result was higher than that with 0.2% bactocease and potassium sorbate and similar to that with 0.8% bactocease. Consequently, 0.4% bactocease was chosen as the best concentration for preparing the fried fish paste. Microbial growth on fried samples treated with preservatives was more inhibited by adding preservatives regardless of their type than that of the control after 15 days of storage. In addition, there were no significant differences in the quality between the samples treated with 0.4% bactocease and 0.2% potassium sorbate, such as volatile basic nitrogen contents, TBARS values, pH, and acidity. Therefore, these results indicate that food preservatives should be added into fried fish paste for controlling microbial growth, and bactocease can have a high potential to replace potassium sorbate in processed marine foods, including fried fish paste.

국내 유통되는 반려동물 사료의 살모넬라 분석시 증균 배양법, 효소면역기법에 의한 분석, 종 특이 primer를 활 용한 PCR 방법을 활용하여 비교 평가하였다. 시료 175점 Salmonella spp. 검출 결과 증균배양법 및 종 특이 primer를 활용한 PCR 방법에 의한 검출 방법에서 2점의 시료(육포, 옥수수 글루텐)가 양성으로 확인되었고, 효소면역기법에 의한 검출방법에서는 1점의 시료(옥수수 글루텐)가 양성 으로 확인되었다. 증균배양법 및 효소면역기법에 의한 검 출방법에 비해 종 특이 primer를 활용한 PCR 방법을 적 용 할 경우 시료에서 분리된 균주의 종(species) 판별이 가 능하였다.

본 연구는 2021년 2월부터 7월까지 잡곡 106건을 수거 하여 잔류농약 실태조사를 하였다. 대형, 중소형 및 온라 인 유통매장을 중심으로 국내 잡곡 40건과 수입 잡곡 66 건을 수거하였고, GC/MSMS, GC/ECD, GC/NPD, LC/ MSMS, UPLC/PDA, HPLC/FLD를 이용하여 다종농약 다 성분분석법으로 잔류농약 341종을 분석하였다. 잔류농약 이 검출된 잡곡은 대형유통매장 1건, 중소형 유통매장 2 건, 온라인 유통매장 5건으로 총 8건(7.5%)이었고, 5건 (4.7%)에서는 농약잔류허용기준을 초과하였다. 이들 잡곡 에서는 MGK-264, chlorpyrifos, thiamethoxam, malathion, piperonyl butoxide, pirimiphos-methyl 등 6종의 농약 성분 이 검출되었다. 검출된 잡곡은 강낭콩(1건), 녹두(6건), 수 수(1건)이다. 검출된 잡곡 중 농약잔류허용기준을 초과한 품목은 수입 녹두(5건)로 미얀마산이었고, 초과한 농약 성 분은 thiamethoxam이었다.

PURPOSES : In this study, the results of an intensive field survey of a composite pavement applied to an expressway in Korea are analyzed. The results are intended to be used as basic data for evaluating the composite pavement and for preparing quality control measures through a review and analysis of the change in the state of the tensile bonding strength of the composite pavement. METHODS : To evaluate, repeated field coring and indoor tensile bonding strength evaluations are conducted for five years, and the commonality evaluation of pavement using pavement condition investigation equipment is conducted annually. RESULTS : The results of this study show that the degree of reflective crack generation varies depending on the type of concrete pavement and type of asphalt mixture applied to the intermediate layer, and that the CRCP composite pavement exhibits better initial commonality than the JCP composite pavement. In addition, it is confirmed that the composite cross-section pavement section with MASTIC applied as an intermediate layer shows excellent adhesion performance between the lower concrete layers from the beginning of construction in all sections, as well as satisfied the quality control standards for good pavement and tensile adhesion even after approximately five years of public use. CONCLUSIONS : Based on a follow-up survey of the composite pavement testing sections, it is confirmed that the section constructed with the MASTIC intermediate layer and CRCP satisfies the quality control standards for good pavement conditions and tensile adhesion even after approximately five years of public use.

Bullets flying with a light from the back are called “tracers”. Tracers are ignited by the combustion gas of the propellant and emit bright light that allows the shooter to visually trace the flight path. Therefore, tracers mark the firing point for allies to assist shooters to hit target quickly and accurately. Conventional tracers are constructed with a mixture of an oxidizing agent, raw metal, and organic fuel. Upon ignition, the inside of the gun can be easily contaminated by the by-products, which can lead to firearm failure during long-term shooting. Moreover, there is a fire risk such as forest fires due to residual flames at impact site. Therefore, it is necessary to develop non-combustion type luminous material; however, this material must still use the heat generated from the propellant, so-called “thermoluminescence (TL)”. This study aims to compare the TL emission of Dy3+, La3+ and Ho3+ doped MgB4O7 phosphors prepared by solid state reaction. The crystal structures of samples were determined by X-ray diffraction and matched with the standard pattern of MgB4O7. Luminescence of various doses (200 ~ 15,000 Gy) of gamma irradiated Dy3+, La3+ and Ho3+ (at different concentrations of 5, 10, 15 and 20 %) doped MgB4O7 were recorded using a luminance/color meter. The intensity of TL yellowish (CIE x = 0.401 ~ 0.486, y = 0.410 ~ 0.488) emission became stronger as the temperature increased and the total gamma-ray dose increased.

This study was carried out to investigate the proper wattage and installation distance for the efficient use of nano-carbon fiber infrared heating lamp (NCFIHL), a heating device advantageous for heating energy saving, when the production of watermelon plug seedlings in the plug seedling nursery in winter season. Six small beds were divided into plastic film, and 700 W and 900 W nano-carbon fiber infrared heating lamps were installed at 100 cm above the bed. 1 lamp at central (control), 60 cm interval (2 lamps), and 40 cm interval (3 lamps) heating lamps were installed in each bed inside the greenhouse. All treatments, except the control, were set to keep the night air temperature at 20℃ after lighting the NCFIHL. The leaf temperature showed a tendency to increase fast as the install distance was narrow. The leaf length and leaf width tended to increase as the installation distance of the 700 W heating lamp was narrow. The compactness was high in 700 W heating lamp with 40 cm of installation distance. Therefore, in consideration of maintaining the set temperature at night, installing 700 W electric lamps at 40 cm was an efficient power and installation distance for watermelon grafted seedlings considering economic feasibility.

This study was conducted on October 23, 2020 at the Cheongpyeong Reservoir located in Seorakmyeon, Gapyeong-gun, Gyeonggi-do, and analyzed the horizontal and vertical distribution patterns of fish based on data obtained using fishfinder. The total surface area of fishfinder survey conducted was 782,853 m2, and where the water depth (WD) ranges from 10 m to 12 m is widest which 31.7% of total surface area. As a result of the heat map analysis, fish density was highest at right bank under the Gapyeong-bridge, but there was no specific pattern in horizontal distribution of fish. As a result of vertical distribution of fish analysis, 86.6% of fishes are observed at below 6 m of the fish depth (FD, distance from water surface to fish). As a result of the relative height (RH, water depth-distance from bottom to fish ratio) analysis, there was a tendency that fishes are distributed in near surface area more as the WD increased. This tendency could have various reasons such as water temperature gradient along the water depth, and further studies are required for detailed explanation.

Indoor air quality management is essential for a healthy life. However, it is difficult to perceive, detect, and monitor the level of indoor air pollution and this means that it is possible to be exposed to more pollution indoors than outdoors. In this study, in order to derive effective indoor air quality management measures, public perceptions and behavioral characteristics regarding indoor particulate matter and air quality management methods were investigated through a survey of 1,000 people. Based on the survey, it was found that most of the respondents had a negative perception of the indoor air quality of their residence, and natural ventilation was the most used method for indoor air quality management. Although the frequency of use of air quality management devices such as air purifiers and mechanical ventilation systems was relatively low, their effect regarding air quality management was positively perceived. In particular, the results of survey indicated that respondents of families which included members with fragile health engaged in more active behavior regarding in indoor air quality management than those respondents whose family members had no health issues and that the former have used air quality management devices more frequently. Therefore, it is necessary to develop proper guidelines to encourage more people to actively participate in improving indoor air quality.