In this study, heavy metals (lead, cadmium, and mercury) and shellfish poisoning toxins (diarrhetic shellfish poisoning toxins, amnesic shellfish poisoning toxins) were investigated in a total of 104 shellfishes. According to the analysis of heavy metals, lead (Pb) was detected in the range of 0.0177-0.5709 mg/kg, cadmium (Cd) was detected in the range of 0.0226-1.4602 mg/kg, and mercury (Hg) was detected in the range of 0.0015-0.0327 mg/kg. Levels of Pb, Cd, and Hg were acceptable by Korean standards. Okadaic acid (OA) and dinophysistoxin-1 (DTX-1) were investigated for monitoring of diarrhetic shellfish poisoning toxins and OA and DTX-1 were not detected. As a result of monitoring of amnesic shellfish poisoning toxins, domoic acid was detected in 5 of 104 samples and detection ratio was 4.8%. The detection period was found as follows; 1 case in January, 1 case in February, 1 case in May, 2 cases in September. These showed that continuous monitoring for the management of shellfish poisoning toxins and heavy metals is required. In addition, this study can be used as reference data to strengthen managing heavy metals in fishery products.

Understanding the characteristics of reservoir water quality is fundamental in reservoir ecosystem management. The water quality of reservoirs is affected by various factors including hydro-morphology of reservoirs, land use/cover, and human activities in their catchments. In this study, we classified 83 major reservoirs in South Korea based on nine physicochemical factors (pH, dissolved oxygen, chemical oxygen demand, total suspended solid, total nitrogen, total phosphorus, total organic carbon, electric conductivity, and chlorophyll-a) measured for five years (2015~2019). Study reservoirs were classified into five main clusters through hierarchical cluster analysis. Each cluster reflected differences in the water quality of reservoirs as well as hydromorphological variables such as elevation, catchment area, full water level, and full storage. In particular, water quality condition was low at a low elevation with large reservoirs representing cluster I. In the comparison of eutrophication status in major reservoirs in South Korea using the Korean trophic state index, in some reservoirs including cluster IV composed of lagoons, the eutrophication was improved compared to 2004~2008. However, eutrophication status has been more impaired in most agricultural reservoirs in clusters I, III, and V than past. Therefore, more attention is needed to improve the water quality of these reservoirs.

This study aimed to investigate pesticide residues in 160 stalk and stem vegetables marketed in Northern Gyeonggi-do. The QuEChERS method using GC-MS/MS and LC-MS/MS was employed to analyze the residues of 341 pesticides in the samples. The maximum or lower than the residue limit was recorded in 75 samples (46.9%), while 4 samples (2.5%) exceeded the maximum residue limit (MRL). Thirty-nine kinds of residual pesticides were detected including fungicides (14), insecticides (22), herbicides (2), and plant growth regulator (1). Carbendazim and pendimethalin were the most frequelntly detected pesticides. Fenitrothion, procymidone, and diazinon exceeded MRL in garlic chives, and Welsh onion. This indicated that these vegetables along with water celery should be constantly monitored.

본 연구는 호주-중국 무역분쟁을 국제정치의 상호역학관계 관점에서 분 석하였다. 연구목적을 달성하기 위해 시스템사고 이론에 기반하여 인과지 도분석을 실시하였다. 연구를 통해 얻어진 결과는 다음과 같다. 첫째, 경제 적 영역에서 시작된 무역분쟁은 다양한 영역으로 확산되면서 복잡한 국제 정치시스템으로 진화하는 것으로 나타났다. 둘째, 다양한 변수들이 작동하 는 국제관계 현실에서 절대적 가치만을 선호하는 중국의 보호된 가치(중화 사상, 하나의 중국, 중국식 인권주의)는 정책결과의 확증편향을 유발하면서 국제관계에서 다양한 변수들의 동태적 변화를 인식하지 못하게 하는 원인 으로 작용하는 것으로 나타났다. 셋째, 한국과 호주는 중국과의 외교관계에 서 상당히 유사한 조건을 가지고 있다는 점에서 호주-중국의 무역분쟁에서 호주가 사용한 전략은 한국의 정책결정에 교훈을 주고 있다는 점을 발견할 수 있었다.

This study was conducted to analyze geminate consonant errors(안에 [an.ɛ] → *안네[an.nɛ]) produced by Chinese learners during their acquisition of Korean linking sounds within the framework of Optimality Theory. The study was further intended to find possible constraints and causes applicable to the error. This paper argues that this error results from the interplay of the Align-R constraint, where the boundaries of a morpheme and syllable are aligned in the learner’s mother tongue, and the onset constraint, which is required for CV, a universal linguistic syllable. This study identifies the cause of the geminate consonant errors among Chinese leaners as the consequence of the simultaneous influences of interference from the learners’ native language and of linking sounds, which occur universally in linguistics.

This study was to investigate an analytical method for determining dieckol content in Ecklonia stolonifera extract. According to the guidelines of International Conference on Harmonization. Method validation was performed by measuring the specificity, linearity, precision, accuracy, limit of detection (LOD), and limit of quantification (LOQ) of dieckol using high-performance liquid chromatography–photodiode array. The results showed that the correlation coefficient of calibration curve (R2) for dieckol was 0.9997. The LOD and LOQ for dieckol were 0.18 and 0.56 μg/mL, respectively. The intra- and inter-day precision values of dieckol were approximately 1.58-4.39% and 1.37-4.64%, respectively. Moreover, intra- and inter-day accuracies of dieckol were approximately 96.91- 102.33% and 98.41-105.71%, respectively. Thus, we successfully validated the analytical method for estimating dieckol content in E. stolonifera extract.

본 논문에서는 축하중과 폭발하중을 동시에 받는 철근콘크리트 부재의 구조 거동을 분석하였다. 기본적인 폭발하중을 받는 패널 실험 데이터, 축하중과 폭발하중을 받는 철근콘크리트 기둥 실험데이터를 이용하여 비선형 동적해석 모델링을 검증하였다. 축하중의 적용에 있어서 Autodyn은 동적해석만을 위한 프로그램이기 때문에 축하중과 같은 정적 하중에 대한 초기 응력 상태를 모사하는 해석 절차를 제시하였다. 축하중비 0%~70% 구간과 TNT 등가량에 의존한 환산거리 1.1~2.0에 해당하는 매개변수를 선정하여 총 80개의 비선형 동적 유한요소해석을 진행하였다. 축하중비와 환산거리의 변화를 통해 손상정도와 최대 변위 및 회전각으로 구조 거동을 비 교 분석한 결과로 원거리 폭발하중에서 축하중을 받는 기둥의 강성 증가로 최대 변위가 감소한다. 결과적으로 축하중비 10%~30%, 30%~50%, 50% 이상의 영역 3가지로 구조적 거동 분류가 가능함에 따라 내폭 설계 모델 개발에 활용될 수 있을 것으로 보인다.

The research aims to develop a rapid and easy analytical method for methoprene using liquid chromatography- tandem mass spectrometry (LC-MS/MS). A simple, highly sensitive, and specific analytical method for the determination of methoprene in livestock products (beef, pork, chicken, milk, eggs, and fat) was developed. Methoprene was effectively extracted with 1% acetic acid in acetonitrile and acetone (1:1), followed by the addition of anhydrous magnesium sulfate (MgSO4) and anhydrous sodium acetate. Subsequently, the lipids in the livestock sample were extracted by freezing them at -20oC. The extracts were cleaned using MgSO4, primary secondary amine (PSA), and octadecyl (C18), which were then centrifuged to separate the supernatant. Nitrogen gas was used to evaporate the supernatant, which was then dissolved in methanol. The matrix-matched calibration curves were constructed using 8 levels (1, 2.5, 5, 10, 25, 50, 100, 150 ng/mL) and the coefficient of determination (R2) was above 0.9964. Average recoveries spiked at three levels (0.01, 0.1, and 0.5 mg/kg), and ranged from 79.5-105.1%, with relative standard deviations (RSDs) smaller than 14.2%, as required by the Codex guideline (CODEX CAC/GL 40). This study could be useful for residue safety management in livestock products.

The smart factory is an important system that can reduce defects, maximize productivity, and respond to customer needs, from the labor-intensive era of traditional small and medium-sized manufacturing companies through the automation era to CPS using ICT. However, small and medium-sized manufacturers often fall short of the basic stage due to economic and environmental constraints, and there are many companies that do not even recognize the concept of a smart factory. In this situation, to expand the smart factory of small and medium-sized enterprises, the project to support the establishment of a smart factory for the win-win between large and small enterprises. The win-win smart factory construction support project provides a customized differentiation program support project according to the size and level of the company for all domestic manufacturing SMEs regardless of whether or not they are dealing with Samsung. In this study, we analyze the construction status and introduction performance of companies participating in the win-win smart factory support project to find out whether they have been helpful in management and to find efficient ways to improve support policies, and to suggest the direction of continuous support projects to improve the manufacturing competitiveness of SMEs in the future.

농경지에서 작물이 필요로 하는 이상으로 양분이 과다하게 투입되는 경우 작물의 생육을 저해하거나 환경오염원으로 작용하게 된다. 우리나라 농경지 양분수지는 다른 OECD 국가에 비해 월등히 높은 수준이며, 과다양분 투입 때문에 수질과 대기 등 농업환경의 오염과 생물다양성 저하가 유발되고 있다. 환경부의 ‘양분관리제’ 도입, 농특위의 ‘토양 양분관리제 도입’ 의결과 같은 정부 정책은 이러한 과다양분 투입을 개선하기 위한 노력으로서, 이러한 정책을 뒷받침하고 환경적⋅사회경제적 성과를 도출하기 위해서 농업분야 양분수지 개선에 따른 공익적 기능의 발굴과 공익가치 의 평가가 필요하다. 본 연구의 목적은 메타분석 기법을 적용하여 선행연구에서 추출한 다양한 공익적 기능에 대한 가치평가 추정치를 이용하여 양분수지 개선의 공익가치를 간접적으로 추정하는 데 있다. 공익기능에 대한 연간 가구별 한계지불의사액을 추정한 결과, 수질개선은 약 60,315원/년, 기후조절은 139,740원/년, 토양보전 및 정화는 109,179원/년, 생물다양성은 150,213원/년으로 나타났다. 추정한 한계지불의사액과 산정된 기여율을 이용하여 공익가치를 추정하면 수질개선은 7,596억 원, 기후조절은 5,715억 원, 토양보전 및 정화는 3,380억 원, 생물다양성은 8,124억 원으로 추정된다. 이러한 결과는 향후 농업 환경보전 프로그램이나 정책을 추진하는 데 있어 객관적인 자료가 될 수 있을 것이다.

The official analytical method for the analysis of harmful heavy metals in Meju, distributed in Korea, employs a strong acid to decompose the organic components. This analysis is time consuming and harmful to the users and/or the environment. This study aimed to develop a new pre-treatment technology using laser ablation, to rapidly analyze harmful heavy metals without using strong acids. The results obtained from this method were validated by the National Institute of Food and Drug Safety Evaluation guideline (NIFDS, 2016). Moreover, a comparison of the two methods showed that the analytical time for 55 Meju samples was shortened by 96% or more in the new method. The results showed no significant difference in the recovery ranging from 90–120%. The proposed method proved suitable for detecting harmful heavy metals in Meju.

Microcystins (MCs) are cyano-toxins mainly produced by cyanobacteria in the genera of Microcystis, Anabaena, and Oscillatoria. The concentrations of MCs in the water bodies and fish tissues taken from the four weirs (Ipo, Gangjeong-goryeong, Baekje, and Juksan) in the four main rivers in Korea, and the health risk of human due to consumption of toxin-detected fish was examined. The maximum values of MCs concentration in the water samples were as follows: Juksan (3.261 μg L-1), Gangjeong-goryeong (1.014 μg L-1), Baekje (0.759 μg L-1), and Ipo (0.266 μg L-1) weirs. The MC-RR concentration was the highest among the MCs, and MC-YR was not detected. MCs of 0.222~9.808 μg g-1 dry weight were detected in the liver of 3 out of 215 fishes of 16 species, and below the detection limit in muscle. As a result of comparing the feeding characteristics of the collected fishes and toxin concentrations in water and fish tissue, it was concluded that the biomagnification of MCs through the food chain did not occur. It was judged that there was no health risk due to the consumption of the fish detected the toxin, based on the amount of the fish intake of the Korean people and the allowable daily intake of MCs. However, in order to reduce the health risk due to MCs, further studies should be conducted to analyze the concentration of MCs contained in fish tissues collected at various times in the area dominated by harmful cyanobacteria to obtain data on the exposure of MCs due to fish consumption. In addition, it is necessary to establish the management guidelines for MCs in fish tissues.

The occurrence of cyanobacterial blooming and the contaminant sources were analyzed in the downstream of Jecheon Stream, a tributary of Chungju Reservoir. The concentrations of chlorophyll a at the Myungseo Fishing Point (GPS; 37°03′25.5″N, 128°03′13.6″E) were 399.2 and 184.8 mg m-3 on October 18, 2015 and September 25, 2016, respectively, and the concentrations of total microcystins, a cyanobacterial toxin mainly produced by Microcystis, were 124.09 and 79.71 μg L-1, respectively. The occurrence of cyanobacterial blooming at the downstream of Jecheon Stream was closely related to the water level of Chungju Reservoir. The cyanobacterial blooming occurred after the increase of water level in Chungju Reservoir, when the water body stagnated. As a result of analyzing National Water Quality Monitoring Data of the upper region of Jecheon Stream, the main source of pollutant was Jangpyeong Stream, the tributary of Jecheon Stream, and the discharge water from Jecheon Wastewater Treatment Plant located in Jangpyeong Stream was considered to be the most important source of contaminant.

최근 탄소 중립 정책에 따른 신재생에너지 활용을 위한 노력이 가속화되고 있다. 이를 위하여 본 연구에서는 바이오매스 작물 중 하나인 케나프 (Hibiscus cannabinus L.)를 연료화하기 위하여, 미이용 목재 자원과 폐목재 자원을 혼합하여 고형연료인 펠릿을 제조하고 품질을 분석하였다. 품질을 평가하기 위해 목재 펠릿, 비목재 펠릿과 Bio-SRF의 품질기준을 통해 성형한 펠릿의 품질을 파악하였다. 케나프 펠릿의 경우 겉보기밀도, 발열량 등에서는 목재 펠릿 품질기준을 만족하였으나 회분의 함량이 기준을 초과하였다. 이를 보완하기 위해 목재 자원인 폐목재를 혼합하여 제조한 펠릿의 특성을 조사한 결과, 질소 및 겉보기밀도, 회분, 발열량 등에서 오히려 품질을 저하시키는 경향을 보이는 것으로 나타났다. 한편, 미이용 목재를 혼합하여 성형된 펠릿의 품질을 조사한 결과, 겉보기밀도, 함수율, 질소, 황, 발열량의 조건에서 대부분 목재 펠릿의 품질기준을 만족하였다. 다만 회분함량의 경우 비목재 펠릿 및 Bio-SRF의 15% 이하 기준을 만족하고 있지만, 목재 펠릿의 최저 기준인 B등급 2.0% 이하 기준의 경우 만족하는 경우와 만족하지 못하는 경우가 발생하였다. 함수율 15%(w.b.)에서 케나프와 미이용 목재의 혼합비가 2:8인 경우와 함수율 20%(w.b.)에서 케나프와 미이용 목재의 혼합비가 6:4 및 2:8인 경우에 기준을 만족하였고, 그 이외에는 기준을 만족하지 못하였다. 특히, 케나프만을 사용하거나 폐목을 섞은 경우는 모두 기준을 만족하지 못하므로, 목재 펠릿의 기준을 만족하는 연료 이용을 위해서는 케나프와 미이용 목재 자원을 혼합 활용하는 것이 바람직할 것으로 판단된다.

The purpose of the study is to suggest policy recommendations for mid- to long-term strategies through performance evaluation of food assistance implemented by the Korean government. Since Korea became a member of the FAC (Food Assistance Convention) in 2018, the government has been focusing on eradication of starvation by cooperating with the international community, recognizing the basic human needs and providing food to hungry people around the world. However, the existing way of food assistance is to meet the FAC pledge contributions to comply with international norms and maintain humanitarian support. Thus, it is necessary to establish a long-term strategy for effectiveness and efficiency of the food assistance. The study find out that there would be a high possibility to expand the scale of the current food assistance program of Korea by utilizing the imported rice without a conflict.

As modern society has emerged and developed, the subway has established itself as a representative means of transportation in the city due to its speed, accuracy, and accessibility. According to the Indoor Air Quality Management Act, underground stations have established and managed the maintenance and recommendation standards for PM10, PM2.5, CO2, CO, HCHO, NO2, Rn, VOCs However, th the standards for airborne mold has not been applied for subway stations even though management for the health effect of exposure to mold is necessay. In this study, the correlation with major contributing factors was analyzed by measuring the concentration of airborne molds in the indoor air of underground stations and through literature research. It was confirmed that there was a correlation between the concentration of airborne molds in subway stations and the major contributing factors. As a result of the analysis, it was found that the concentration of airborne molds became higher as the location of the platform became deeper underground, during periods of congestion, and especially in summer. There was no significant correlation with the year of construction. Our findings indicate that appropriate management measures should be devised in response to such contributing factors.

본 연구는 먼저 산업정책에 있어 정부의 개입 정도에 따른 학파별 시 각 차이를 중심으로 살펴보고, 한국의 디지털산업 지원정책을 기업의 활 동단계에 따른 정책수단들을 중심으로 문헌고찰을 활용한 현황분석을 실 시하였다. 이에 따라 다음과 같은 함의를 얻었다. 첫째, 한국의 디지털산 업 지원정책은 단순 특정 산업을 선도적으로 육성하거나 직접 지원하는 방식에서 기업들의 기술개발 투자 및 사업화와 창업을 위한 법제도 및 표준화 제정, 세제 및 금융 지원, 인력양성 및 인프라 지원 등의 산업기 술기반을 조성하는 방식으로 변화했고, 다양한 정책수단들이 정책목표 달성을 위해 연계되는 추세로 나타났다. 둘째, 한국의 디지털산업 지원정 책은 포괄적 지원에서 전략적 지원으로 진화했다. 셋째, 한국의 디지털산 업 지원정책을 통해 살펴본 시장에 대한 정부의 개입 방식에 대한 변화 를 보면, 시장과 정부의 대립과 갈등의 관계를 전제한 신고전학파적 관 점에서 점차 대립관계가 아닌 보완관계를 전제한 상호 간 전략적 협력관 계로 변화하며 기업과 정부의 역할이 더욱 명확히 구분되며 발전했다. 본 연구는 디지털산업에 대한 정책수단을 기업의 활동단계에 따라 분석 함으로써 산업정책 분석의 초점을 산업현장으로 확장하는데 기여하였다.

Fishery products play an important role in Korean food culture, and awareness of the safety of fishery products is increasing in the seafood market. Against this backdrop, Japan has announced a plan to release radioactive water to the sea from 2023. In the case of Korea, it is adjacent to the area to be discharged, so there are concerns about securing the safety of marine products. Therefore, it is necessary to analyze the change in perception and impact of marine product consumers due to the discharge of contaminated water and to study appropriate countermeasures when discharging contaminated water from nuclear power plants. In this study, the current status of radioactive contaminated water discharge in Japan was summarized, and a survey was conducted on the change in the consumption perception of marine products according to the discharge of contaminated water to analyze the factors affecting the consumption change of domestic consumers. According to the survey, 85.3% of the respondents said that it will affect the purchase of domestic marine products if Japan starts discharging contaminated water from nuclear power plants. Moreover, 85.5% of the respondents said it will affect the purchase of imported marine products.

최근 도시 과밀화와 건축물 고층화로 인해 빌딩풍에 의한 시설 피해는 물론 보행자의 안전을 위협하는 풍환경에 대한 우려 가 커지고 있다. 빌딩풍 피해 저감을 위한 방안으로 건축물 주변 풍환경 평가를 통해 도시의 풍환경을 개선하는 것이 중요하다. 이를 위해 풍동실험을 대체하거나 보완하는 수단으로 최근 전산 유체역학 기법 (CFD)의 적용이 받아들여지고 있으며, 국토교통부가 보행 자 풍환경 평가를 위한 CFD 활용 가이드라인을 제시한 바 있다. 본 논문에서는 이 가이드라인의 적정성을 평가하기 위한 전산해석을 수행하였다. CFD 결과의 검증을 위해 일본 건축학회가 제시한 모형과 풍동실험 결과를 사용하였다. 평가결과 일부 위치에서 풍동 실 험값과 CFD 결과의 풍속 차이는 있으나 격자의 상세도가 정확도에 미치는 영향과 CFD를 이용한 보행자 풍환경 평가 가능성을 확인 하였다. 또한, 건물 주위의 상승풍, 하강풍 및 와류 등으로 인한 돌풍이 잘 모사되고 있음을 확인하였다.

Purpose: This study aims to examine the basic data of online practice nursing education after categorizing the subjective perceptions of online practice among nursing students and closely examining the characteristics of each type using the Q-methodology. Methods: The Q-methodology was used. The 34 Q-statements selected by each of the 40 participants were classified into a shape of normal distribution. Results: The online practice in the nursing practice was classified into the four following types: the “self-development emphasis,” “online practice beneficial,” “cognitive type of difficulty in online practice,” and “fear in case of being employed” types. Conclusion: The practice education content that is most similar to the clinical field training is expected to be developed when supplementing negative aspects and further reinforcing positive aspects in the online practice having been verified in this study.