In this study, surface roughness and interfacial defect characteristics were analyzed after forming a high-k oxide film on the surface of a prime wafer and a test wafer, to study the possibility of improving the quality of the test wafer. As a result of checking the roughness, the deviation in the test after raising the oxide film was 0.1 nm, which was twice as large as that of the Prime. As a result of current-voltage analysis, Prime after PMA was 1.07 × 10 A/cm2 and Test was 5.61 × 10 A/cm2, which was about 5 times lower than Prime. As a result of analyzing the defects inside the oxide film using the capacitancevoltage characteristic, before PMA Prime showed a higher electrical defect of 0.85 × 1012 cm2 in slow state density and 0.41 × 1013 cm2 in fixed oxide charge. However, after PMA, it was confirmed that Prime had a lower defect of 4.79 × 1011 cm2 in slow state density and 1.33 × 1012 cm2 in fixed oxide charge. The above results confirm the difference in surface roughness and defects between the Test and Prime wafer.

A spin coating process for RRAM, which is a TiN/TiO2/FTO structure based on a PTC sol solution, was developed in this laboratory, a method which enables low-temperature and eco-friendly manufacturing. The RRAM corresponds to an OxRAM that operates through the formation and extinction of conductive filaments. Heat treatment was selected as a method of controlling oxygen vacancy (VO), a major factor of the conductive filament. It was carried out at 100 oC under moisture removal conditions and at 300 oC and 500 oC for excellent phase stability. XRD analysis confirmed the anatase phase in the thin film increased as the heat treatment increased, and the Ti3+ and OH- groups were observed to decrease in the XPS analysis. In the I-V analysis, the device at 100 oC showed a low primary SET voltage of 5.1 V and a high ON/OFF ratio of 104. The double-logarithmic plot of the I-V curve confirmed the device at 100 oC required a low operating voltage. As a result, the 100 oC heat treatment conditions were suitable for the low voltage driving and high ON/OFF ratio of TiN/TiO2/FTO RRAM devices and these results suggest that the operating voltage and ON/OFF ratio required for OxRAM devices used in various fields under specific heat treatment conditions can be compromised.

Among various environmental stresses, humid stress lacks mechanisms and biochemical understanding compared to drought, low temperature, and high salt stresses. The aim of this study was to investigate enzyme activity of field crops under humidity stress. Results of this study could be used as basic data for understanding humidity stress and early diagnosis. Growth and enzyme activities of sesame, perilla, red beans, sorghum, and beans as major field crops in Korea when flooded were investigated. It was confirmed that growths of both shoots and roots were retarded. In plants, anaerobic fermentation occurred due to flooding stress, which increased the activity of alcohol dehydrogenase (ADH) compared to the control group. Increases of reactive oxygen species (ROS) were also observed. All flooded plants showed increased peroxidase (POD) activity and lipid peroxidation. Their dyeing strength was darker than that of the control group, even in 3,3´-diaminobenzidine (DAB) staining. Since enzyme activity changes in plants appear relatively faster than changes in phenotype at the ground level, they could be used as biomarkers for early diagnosis of humidity stress in crops.

An estuary is a water ecosystem with a high abundance of the species diversity, due to a variety of complex physicochemical factors of the area where freshwater and ocean mixed. The identification of Corbicula species in the estuary environments is difficult because of various morphological characteristics. In this study, we provide taxonomic information on Corbicula species with taxonomic difficulties using morphological and genetic analysis. This study was conducted on clams from the Seomjin River-Gwangyang Bay, one of the major production area of marsh clam in Korea. As a result, we characterized Cytocrome C Oxidase subunit I (COI) sequences of the Corbicula. The 636 bp nucleotide sequences of COI have 98% homology among Corbicula species collected from 2 sites of Seomjin River-Gwangyang Bay. The phylogenetic analysis with 17 species of Corbicula indicated that most of the species collected from Seomjin River-Gwangyang Bay were brackish water clam (Corbicula japonica), and only one Asian clam (Corbicula fluminea). The evolutionary distance between C. japonica and C. fluminea was less than 0.003. Therefore, it was confirmed that C. japonica is phylogenetically closely related to C. fluminea. In 9 species of Cyrenidae, phylogenetic tree was classified into three lineages. These results will be used as an important data for an identification of clam species by providing genetic information for Corbicula species with a morphological diversity. Key words: Corbicula japonica, cytochrome c oxidase subunit I (

In this paper, based on the existing research, we define the parameters for the number of ignition devices to be applied to the pyrovalve, the operation and airtightness according to the temperature, the material of the nipple and the thickness of the fractured part, and ANSYS Ver. 19.2 was used to analyze the FEA model, and a comparative analysis was conducted through structure analysis according to the piston shape of the pyrovalve. In addition, an experimental study was conducted by manufacturing a prototype according to the design variables. As a result, high-strength pyrovalves can stably supply working fluids such as fuel and oxidizer for space launch vehicle propulsion engines, as well as precisely control flow path switching was confirmed.

The Ministry of Oceans and Fisheries promoted the installation of eel-ladder for the purpose of creating inland water resources. Currently, eel-ladder have been installed and operated at the Geumgang Estuary Bank (2018), Yeongam Embankment (2019), and Asanman Embankment (2020). In this study, the number of glass eels in eel-ladder in 2021 was monitored and factors affecting the rise that from ocean to river of eels were investigated. Glass eels in eel-ladder were found when the salinity was relatively low, and they started when the freshwater and seawater temperatures were above 20℃. Comparing the number of occurrences by year, the largest number of glass eels was observed in 2021, but it is judged that this is not according to the distribution of glass eels in sea, but rather as a result of the investigator’s eel-ladder repair and guidance on illegal fishing.

The fish community in the Seomjin River-Seomjin River Estuary-Gwangyang Bay coast continuum was investigated three times from March 2019 to October 2019. The collected species at the eight sites during the survey period were 49 species belonging to 31 families, including two endangered species. According to Bray-Curtis similarities, observations were divided into four groups based on the fish community composition; two groups (group 1, 2) and two uncategorized groups (group 3, 4). ANOSIM based on spatial and temporal groupings indicated that the spatial differences in fish communities (R=0.398, P=0.001) were relatively more important than the temporal differences (analysis of similarities, R=0.273, P=0.002). In particular, there were significant differences between groups 1 and 2 (analysis of similarities, R=0.556, P=0.001), and similarity percentage analysis revealed that Argyrosomus argentatus (9.4%), Favonigobius gymnauchen (6.9%) and Konosirus punctatus (5.9%) contributed to these differences of fish assemblages for each group. The fish fauna distributed in the Seomjin River-Gwangyang Bay ecosystem were spatially divided and the number of species and number of individuals showed seasonal differences. This study could be a basis for understanding changes in the fish community and implementing conservation and management strategies on major species within a continuous environment of the river-estuary-ocean continuum.

The consumption of Flammulina velutipes mushroom imported from Korea has been associated with the cases of listeriosis in the United States, Canada, and Australia. We investigated the effect of sanitizing the plastic wrapper (used in packaging F. velutipes) with slightly acidic electrolyzed water (SAEW) and ultraviolet C waterproof light-emitting diode (UVC-WLED) on reducing the Listeria monocytogenes. Further, the effect of UVC-LED on L. monocytogenes growth in F. velutipes at different storage temperatures (2, 4, and 10oC) was determined. The combined (SAEW+UVC-W-LED) treatment for 5–10 min reduced 99.9% of bacterial population from the contaminated plastic wrapper. In addition, the UVC-LED treatment for 3 min reduced the L. monocytogenes concentration in F. velutipes by 0.47 log CFU/g. Moreover, the growth of L. monocytogenes in the treated mushrooms was slower than that of the untreated (control) ones. L. monocytogenes concentration in F. velutipes increased over 3 log CFU/g at 2oC and 10oC for 60 and 10 days, respectively. The growth of L. monocytogenes at the bottom of mushrooms was faster than that at the top at both the temperatures. These results indicate that the combined SAEW+UVC-WLED treatment of plastic wrappers and the UVC-LED treatment of mushrooms can be used as potential hurdle technologies to control the risk of L. monocytogenes in mushrooms prior to packaging at farms.

본 연구에서는 정서곤충을 이용한 치유프로그램 활동이 지역아동센터를 이용하는 아동 43명의 스트레스에 미치는 영향을 조사하였다. 치유 프로그램에 이용된 정서곤충은 누에나방[Bombyx mori (Linnaeus)]이다. 스트레스의 정도는 타액 ɑ-아밀라아제 검사를 통해 측정하였다. 스트레 스 수치를 평가하기 위한 타액 샘플 채취와 곤충 선호도에 대한 설문지는 곤충치유활동에 참여하기 전과 후에 측정되었고, 활동을 모두 마친 후에는 치유프로그램 참여 경험에 대한 만족도 점수를 평가하였다. 분석 결과, 곤충치유프로그램 활동은 참여 아동의 타액 ɑ-아밀라아제 수치를 통계적으 로 낮추고, 곤충에 대한 선호도를 높여준다는 결과를 확인하였다. 누에를 이용한 치유프로그램 활동에 참가한 아동들의 만족도는 5점 만점에 4.23 점이었다.

Valves are one of the indispensable components in modern industry. Filling and de-pressure connectors in rocket valves used for space launch vehicles are very important parts for smooth fluid supply. For this reason, an optimized design that can improve efficiency, miniaturization, weight reduction, and safety of the valve at the same time is required. In this work, flow analysis and structural analysis were performed through 3D modeling using computational numerical analysis for open type filling and de-pressure valves. As results, the flow velocity and pressure distribution of the fluid were analyzed through the flow analysis of valve, and stress distribution was conducted in structural analysis. Through this study, it is consequently expected to provide valves of various specifications by performing production and performance test evaluation of development prototypes.

｢곤충산업의 육성 및 지원에 관한 법률｣ 제6조에 따라 국립농업과학원에서는 2020년도에 곤충산업 종사자를 대상으로 실태조사를 실시하 였다. 곤충산업 종사자의 유형은 생산업이 가장 많았고(98.5%), 남성 비율이 높았으며(80.4%), 연령은 50대가 36.4%로 가장 많았다. 산업곤충 의 생산 유형은 식약용 곤충 66.5%, 사료용 12.8%, 애완용 20.7%였으며, 식약용 곤충 중 흰점박이꽃무지는 69.6%로 가장 많이 생산되고 있었 으며, 사료용으로는 귀뚜라미류가 31.2%, 애완(정서)용으로는 장수풍뎅이가 45.6%로 가장 많이 생산되고 있었다. 제품의 형태는 분말이 68.5% 로 가장 높았고, 생물로 판매되는 경우는 40.9%로 조사되었다. 연간 소득이 있는 곤충농가는 77.3%이고, 그 중에서 연간 판매금액이 2천만원 미 만인 경우가 65.4%를 차지하였다. 곤충산업 종사자들의 가장 큰 애로사항은 판로 확보로 조사되었다(84.0%). 이와 같이 곤충산업 종사자는 매 년 늘어나고 있지만 20대~40대 청년 곤충농가 대표는 줄어들고 있고, 생산은 특정 대표 곤충 종에 한정되어 있으며, 매우 영세하게 농가가 유지 되고 있음을 알 수 있다. 또한 곤충 농가에서는 판로확보에 가장 큰 어려움을 느끼고 있어 산업곤충 소비 촉진을 위한 이용 기술 개발이 시급하다 고 판단된다.

A pump-type eDNA filtering system that can control voltage and hydraulic pressure respectively has been developed, and applied a filter case that can filter out without damaging the filter. The filtering performance of the developed system was evaluated by comparing the eDNA concentration with the conventional vacuum-pressured filtering method at the catchment conduit intake reservoir. The developed system was divided into a voltage control (manual pump system) method and a pressure control (automatic pump system) method, and the pressure was measured during filtering and the pressure change of each system was compared. The voltage control method started with 65 [KPa] at the beginning of the filtering, and as the filtering time elapsed, the amount of filtrate accumulated in the filter increased, so the pressure gradually increased. As a result of controlling the pressure control method to maintain a constant pressure according to the designed algorithm, there was a difference in the width of the hydraulic pressure fluctuation during the filtering process according to the feedback time of the hydraulic pressure sensor, and it was confirmed that the pressure was converged to the target pressure. The filtering performance of the developed system was confirmed by measuring the eDNA concentration and comparing the voltage control method and the hydraulic control method with the control group. The voltage control method obtained similar results to the control group, but the hydraulic control method showed lower results than the control group. It is considered that the low eDNA concentration in the hydraulic control method is due to the large pressure deviation during filtering and maintaining a constant pressure during the filtering process. Therefore, rather than maintaining a constant pressure during filtering, it was confirmed that a voltage control method in which the pressure is gradually increased as the filtrate increases with the lapse of filtering time is suitable for collecting eDNA. As a result of comparing the average concentration of eDNA in lentic zone and lotic zone as a control group, it was found to be 96.2 [ng μL-1] and 88.4 [ng μL-1l], respectively. The result of comparing the average concentration of eDNA by the pump method was also high in the lentic zone sample as 90.7 [ng μL-1] and 74.8 [ng μL-1] in the lentic zone and the lotic zone, respectively. The high eDNA concentration in the lentic zone is thought to be due to the influence of microorganisms including the remaining eDNA.

Here, we report the development of a new and low-cost core-shell structure for lithium-ion battery anodes using silicon waste sludge and the Ti-ion complex. X-ray diffraction (XRD) confirmed the raw waste silicon sludge powder to be pure silicon without other metal impurities and the particle size distribution is measured to be from 200 nm to 3 μm by dynamic light scattering (DLS). As a result of pulverization by a planetary mill, the size of the single crystal according to the Scherrer formula is calculated to be 12.1 nm, but the average particle size of the agglomerate is measured to be 123.6 nm. A Si/TiO2 core-shell structure is formed using simple Ti complex ions, and the ratio of TiO2 peaks increased with an increase in the amount of Ti ions. Transmission electron microscopy (TEM) observations revealed that TiO2 coating on Si nanoparticles results in a Si-TiO2 core-shell structure. This result is expected to improve the stability and cycle of lithium-ion batteries as anodes.

본 연구는 제주지역에서 사육되고 있는 제주 재래돼지기반의 제주흑돈(제주재래돼지 합성돈)에 대하여 산육형질인 등지방 두께, 일당증체량, 90 kg 도달일령에 대한 후보유전자 탐색을 위해 전장유전체 분석을 실시하였고, 유전체 육종가의 정확도 비교를 위해 베이지안 방법(BayesB, BayesC), π(0.00, 0.50, 0.90, 0.99)값과 개체 자신과 후대의 정보만 포함하고 조상의 정보에 대해 정보를 보정한 DEBVexcPA (Deregressed EBV exlude parents average)와 부모 평균을 포함한 DEBVincPA (Deregressed EBV include parents average)의 반응변수를 이용하였다. 산육형질에 대한 전장유전체 분석을 실시한 결과 등지방두께는 KIAA1549 유전자(SSC18 at 11Mb region), 일당증체량과 90 kg 도달일령에서 POLD3(SSC9 at 9Mb region), STX6(SSC9 at 134Mb region) 유전자가 공통적으로 탐색되었다. 유전체의 정확도 범위는 일당증체량 BayesB의 경우 DEBVexcPA와 DEBVincPA에서 각각 0.285~0.305와 0.497~0.510과 BayesC에서 0.287~0.296와 0.499~0.511으로 추정되었다. 90 kg 도달일령은 BayesB에서 DEBVexcPA와 DEBVincPA는 각각 0.284~0.305와 0.497~0.510, BayesC에서는 0.284~0.296와 0.498-0.511로 추정되었다. 특히, 등지방두께의 유전체 정확도가 BayesB방법론의 DEBVincPA에서 0.625로 가장 높게 추정되었다. 제주흑돈의 산육형질에 대한 유전적인 개량 속도를 가속화하기 위해 유전체 선발법을 적용하는데 있어 부모 평균을 포함한 DEBVincPA (Deregressed EBV include parents average)의 반응변수를 이용하는 것이 바람직하다고 판단된다.

깔따구 (Diptera: Chironomidae)는 저서성 대형무척추동 물로 환경 및 수질 변화에 민감한 영향을 받는 중요한 환경 지표생물이다. 이러한 깔따구 유충이 정수장에서 본 연구에서는 제주 정수처리장에서 발견된 깔따구 유충의 종을 분류하기 위해 형태 사진 및 COI (cytochrome c oxidase subunit I) Primer로 증폭시킨 DNA의 염기서열을 계통수 분석을 통해 분석을 실시하였다. 정수장 내 수도꼭지와 소화관 등에서 채집된 17개체는 둥근깃깔따구 (O. tamarutilus) 14개체, 타마긴털깔따구 (P. tammaater) 3개체 총 2종으로 확인되었다. 각 깔따구 종의 형태적 특징은 두부, 하순기절, 대악, 안테나, 발톱의 형태적 특징의 분류기로 종 동정하였다. NCBI Genbank에 등록된 깔따구 19종 COI 염기서열을 기반으로 본 연구에서 조사된 17개체의 계통진화적 분석 결과 채집된 깔따구 COI 염기서열이 둥근깃깔따구 (O. tamarutilus)와 타 마긴털깔따구 (P. tammaater) 2종으로 각각 계통군 (clade)를 이루는 것이 확인되었다. 이러한 결과는 정수장 환경별 발견 되는 깔따구 유충의 다양성의 확인과 형태적-유전적 종 동정 분류정보를 바탕으로 수환경 관리 및 평가를 위한 기반 정보로 활용될 것이다.

Marine accidents caused by ships are very diverse, such as collision, sinking, stranding, grounding and fire. In particular, persons on passenger ship are unspecified and not trained, so it makes evacuation harder. For this reason, an evacuation plan that considers diverse situation in ship is needed. Effective evacuation planning requires training in consideration of various evacuation situations. In this paper, we investigated the time elapsed on evacuation in various situations from “HANMIR,” the fishery training ship of the Korean Institute of Maritime and Fisheries Technology, using a Ship Evacuation Analysis Program (SEA-Pro) which is introduced to the society. We assumed a situation that has not only inconveniences for real training but also the possibilities of happening. Not all trainees are resting in their cabin, so we assumed positions such as they are in the bridge or engine room and applied fire and flooding situations. We assumed that the time for alerting the situation would be short, so we applied only elapsed time of movement. Those analyses could be helpful in three ways. The first is predicting the consequence of possible accidents. There are some conditions that can be appliable to this model, such as the decreased area of sight in those situations. The second is concluding the optimal limit of carriage and placement of safety instruments on building a new ship. The third is to be a base data for ships to make a new effective evacuation plan based on these analyses.