본 연구에서는 인천광역시에서 유통 중인 한약재의 안 전성을 확인하기 위해 24품목의 50건을 대상으로 345종 의 잔류농약을 분석하였다. 잔류농약은 미량으로도 인체 의 건강에 해를 가할 수 있는 유해 물질로 주의가 필요하 다. 기준 규격외 다양한 잔류농약 확인을 위해, QuEChERS 법으로 전처리후 분석한 결과, 7품목 24건(48%)의 한약재 에서 총 22종의 잔류농약이 검출되었으며, 농약이 검출된 한약재는 천궁, 택사, 당귀, 백지 순으로 많았다. 검출 농 약 중 2건을 제외하고는 모두 기준이 설정되어 있지 않은 농약이었으나, 위해 평가 결과 안전한 수준으로 확인되었 다. 또한, 동일 품목에서 다빈도로 검출되는 농약을 확인 하여, 해당 품목의 지속적인 잔류농약 모니터링의 필요성 을 시사하였으며, 대한약전의 전처리법에 따른 비교분석 에서도 동일한 농약이 검출되어, QuEChERS법을 이용한 생약의 잔류농약 분석 가능성을 제시하였다. 결과적으로, 소비자 안전을 위해서 기준규격 잔류농약 항목 외에도, 생 약에 대한 지속적인 잔류농약 모니터링과 신뢰성 높은 고 효율 분석법 개발 연구가 계속 필요할 것이다.
셰이머스 히니(Seamus Heaney) 시에 드러난 일관된 시학을 탈식민주의적 글쓰기라고 가정한다면, 그의 글쓰기는 단순한 개념의 정치 사회적 주장이라기보다는 기존의 중심주의, 중앙주의, 다수의 시공간적으로 설정된 지점을, 삭제된 주변화, 지역주의, 소수 즉 상징적 개념의 “그늘”로 재현하고 있다. 식민지 이후의 공간과 사람들에 대한 이러한 글쓰기와 이해는 기존의 탈식민주의의 가능성과는 다른 방식으로 작동한다. 히니는 기억을 통해 드러나는 식민공간을 물리적 노동의 생존 공간이자 창의적이고 생산적 공간으로 재현한다. 즉 익명적 노동의 주체와 억압적 역사의 일상이 긍정적 연속성을 획득한 치유의 시간성으로 전이된다. 결국 히니의 역사적 연속성은 민중들의 육체적 노동을 글쓰기라고 하는 정신적 노동과 동일시하는 시적 소재가 된다.
본 연구에서는 유도가열기법을 활용한 콘크리트 촉진 발열양생 기술의 효율성을 평가하기 위하여 철근 배근 및 전도체 변수에 따른 유도가열에 의한 콘크리트 온도향상 성능 및 압축강도를 평가하였 다. 먼저 철근 자체의 유도가열 성능을 평가한 결과, 주철근 및 나선철근 모두 유도가열 직후 10분 이 내에 목표온도인 70℃에 도달하여 충분한 가열성능을 나타내었다. 주요변수로 나선철근의 유무, 나선 철근의 간격, 피복두께, 거푸집 종류, 시험체 크기의 변수를 고려하여 15시간의 유도가열 발열양생 후 압축강도 평가를 실시하였다. 평가 결과, 철근을 포함한 경우 유도가열 발열양생 효율이 약 20~85% 만큼 증가하였다. 또한 총 6종(강섬유, 비정질강섬유, 전기로슬래그, 탄소섬유, 탄소나노튜브, 흑연나노 섬유)의 전도성 재료를 선정하여 재료 자체의 유도가열을 통해 발열성능을 평가하였다. 평가결과 강섬 유, 비정질강섬유, 전기로슬래그는 1~7분 사이에 가열 목표온도인 70℃에 근접하게 도달하여 유도가 열에 의한 콘크리트 발열성능을 향상 시킬 수 있는 혼입재료로 최종 선정하였다. 이상의 3가지 전도체 를 혼입하여 콘크리트를 타설한 뒤 15시간 유도가열 후의 압축강도를 평가한 결과, 강섬유 1%를 혼 입한 경우 발열양생을 실시하지 않은 상온양생에 비하여 강도가 186% 증가하였고, 잔골재의 50%를 전기로 슬래그로 치환한 경우 발열양생을 실시하지 않은 상온양생에 비하여 강도가 187% 상승하였다.
With the increasing demand for electronic products, the amount of multilayer ceramic capacitor (MLCC) waste has also increased. Recycling technology has recently gained attention because it can simultaneously address raw material supply and waste disposal issues. However, research on recovering valuable metals from MLCCs and converting the recovered metals into high-value-added materials remains insufficient. Herein, we describe an electrospinning (E-spinning) process to recover nickel from MLCCs and modulate the morphology of the recovered nickel oxide particles. The nickel oxalate powder was recovered using organic acid leaching and precipitation. Nickel oxide nanoparticles were prepared via heat treatment and ultrasonic milling. A mixture of nickel oxide particles and polyvinylpyrrolidone (PVP) was used as the E-spinning solution. A PVP/NiO nanowire composite was fabricated via Espinning, and a nickel oxide nanowire with a network structure was manufactured through calcination. The nanowire diameters and morphologies are discussed based on the nickel oxide content in the E-spinning solution.
The purpose of this study is to identify the major peacekeeping activities that the Korean armed forces has performed from the past to the present. To do this, we collected 692 press releases from the National Defense Daily over the past 20 years and performed topic modeling and social network analysis. As a result of topic modeling analysis, 112 major keywords and 8 topics were derived, and as a result of examining the Korean armed forces's peacekeeping activities based on the topics, 6 major activities and 2 related matters were identified. The six major activities were 'Northeast Asian defense cooperation', 'multinational force activities', 'civil operations', 'defense diplomacy', 'ceasefire monitoring group', and 'pro-Korean activities', and 'general troop deployment' related to troop deployment in general. Next, social network analysis was performed to examine the relationship between keywords and major keywords related to topic decision, and the keywords ‘overseas’, ‘dispatch’, and ‘high level’ were derived as key words in the network. This study is meaningful in that it first examined the topic of the Korean armed forces's peacekeeping activities over the past 20 years by applying big data techniques based on the National Defense Daily, an unstructured document. In addition, it is expected that the derived topics can be used as a basis for exploring the direction of development of Korea's peacekeeping activities in the future.
Korean melon (Cucumis melo L.) is an environment in which most farming work can affect the increase in musculoskeletal diseases, and the stems are attracted to the ground in order to grow no-heating cultivation. In this study, growth and productivity were compared according to the type of high-bed. The narrower the surface area at the bottom of the high-bed, the faster the initial growth, which was advantageous. The bed is which the height if 70 cm, the surface temperature has risen due to the increase in direct solar radiation inflow since April, requiring side light blocking to block the inflow of solar radiation. In terms of fruit quality, the 200 cm width treatment had higher fruit sugar content and better hardness than the 160 cm treatment. From April to September, the total yield was 6.8 kg/plant of treatment A, 8.7 kg/plant of treatment B, 5.8 kg/plant of treatment C, treatment B mainly 50% higher than treatment C, and 27% higher than treatment A. Therefore, the bed form suitable for Korean melon high bed is 200 cm wide, 40 cm high between the surface and the bed, and the surface of the passage between the beds is 30cm high from the ground to the bed.
The effects of exogenous sodium nitroprusside (SNP, nitric oxide donor) on the growth, yield, photosynthetic characteristics, and antioxidant enzyme activity of kimchi cabbage (Brassica rapa L. subsp. pekinensis (Lour.) Hanelt) was studied under the low temperature conditions. Kimchi cabbages were treated with SNP of three concentrations (7.5, 15, 30 mg·L-1) for three times at four-day intervals and exposed to low temperature (16/7°C) stress for seven days. SNP treatment induced increases of net photosynthetic rate (Pn), stomatal conductance (Gs), intracellular CO2 concentration (Ci) and transpiration rate (Tr) under the stress condition with the highest level after the third treatment. The contents of malondialdehyde (MDA) and H2O2 were significantly lower in the treatment of SNP compared to the non-treated control. The activity of ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD), increased in treated plants by up to 38, 187, 24 and 175%, respectively compared to the non-treated control. SNP-treated and untreated plants had similar growth characteristics. Compared to the control group, SNP-treatment increased fresh weight and leaf area by 5%. Overall, our findings suggest that the application of sodium nitroprusside to the leaves contributes to reducing physiological damage and enhancing the activities of antioxidant enzymes, thereby improving low temperature stress tolerance in kimchi cabbage.
Changes in contents of free sugars, amino acids, and fatty acids of legumes were analyzed for each phase of in vitro digestion. In addition, contents of resistant starch in raw and digested pulses were compared. Soybeans, kidney beans, cowpeas, and chickpeas were analyzed. An in vitro digestion model was used to analyze contents of nutrients using LC-MS and GC-MS. Stachyose in kidneybean, cowpea, and chickpea increased as the digestion phase progressed. In four types of legumes, raffinose slightly decreased or showed no significant difference between the Oral phase and the BBMV phase. Content of glucose, a monosaccharide, increased during the BBMV phase. During the digestion phase, levels of free amino acids and free fatty acids also increased. Content of resistant starch was reduced compared to that in the raw material. It was 0.01g/100 g food in soybean, 1.06 g/100 g food in red kidney bean, 0.77g/ 100g food in cowpea, and 0.76 g/100 g food in chickpea. It was confirmed that nutrients in the in vitro digestion model were liberated at each digestion phase with changes in the content of resistant starch. These results are expected to be used as fundamental data for obtaining bioavailability of nutrients.
This study was conducted to develop a model for predicting the growth of kimchi cabbage using image data and environmental data. Kimchi cabbages of the ‘Cheongmyeong Gaual’ variety were planted three times on July 11th, July 19th, and July 27th at a test field located at Pyeongchang-gun, Gangwon-do (37°37′ N 128°32′ E, 510 elevation), and data on growth, images, and environmental conditions were collected until September 12th. To select key factors for the kimchi cabbage growth prediction model, a correlation analysis was conducted using the collected growth data and meteorological data. The correlation coefficient between fresh weight and growth degree days (GDD) and between fresh weight and integrated solar radiation showed a high correlation coefficient of 0.88. Additionally, fresh weight had significant correlations with height and leaf area of kimchi cabbages, with correlation coefficients of 0.78 and 0.79, respectively. Canopy coverage was selected from the image data and GDD was selected from the environmental data based on references from previous researches. A prediction model for kimchi cabbage of biomass, leaf count, and leaf area was developed by combining GDD, canopy coverage and growth data. Single-factor models, including quadratic, sigmoid, and logistic models, were created and the sigmoid prediction model showed the best explanatory power according to the evaluation results. Developing a multi-factor growth prediction model by combining GDD and canopy coverage resulted in improved determination coefficients of 0.9, 0.95, and 0.89 for biomass, leaf count, and leaf area, respectively, compared to single-factor prediction models. To validate the developed model, validation was conducted and the determination coefficient between measured and predicted fresh weight was 0.91, with an RMSE of 134.2 g, indicating high prediction accuracy. In the past, kimchi cabbage growth prediction was often based on meteorological or image data, which resulted in low predictive accuracy due to the inability to reflect on-site conditions or the heading up of kimchi cabbage. Combining these two prediction methods is expected to enhance the accuracy of crop yield predictions by compensating for the weaknesses of each observation method.
The major active components of Astragalus membranaceus (AM) are isoflavones, which exist in the form of various glycosides. Nuruk is a traditional fermentation starter in Korea, and is suitable for the biotransformation of isoflavone glycosides because it contains various microorganisms and enzymes. This study was performed to determine changes in the isoflavones and antioxidant properties of AM fermented (AF) with nuruk over 24 hours. AF was sampled after 0, 2, 4, 6, 12, 18, and 24 h of fermentation, and calycosin 7-glucoside, ononin, calycosin, and formononetin content, and the antioxidant properties of AF were analyzed. The total phenolic content increased with fermentation time, and the ABTS radical scavenging activity increased until 6 h of fermentation and then decreased. During fermentation, the isoflavone glycosides decreased significantly as fermentation time increased. The contents of calycosin and formononetin, which are aglycons of calycosin-7-glucoside and ononin, increased from 100.54 μg/g to 276.84 μg/g and from 56.29 μg/g to 123.04 μg/g, respectively, at 18 h of fermentation. Significant correlations were observed between fermentation time, isoflavone content, and antioxidant properties. The results of this study showed that fermentation with nuruk is suitable for the biotransformation of isoflavones in AM.
PURPOSES : The main purpose of this study is to identify vulnerable areas by evaluating public transit accessibility for the introduction of smart mobility. METHODS : This study proposes a methodology for analyzing public transportation accessibility. We identified the less accessible areas of public transit in Daegu Metropolitan City by dividing them into low- and high-facilitated areas considering travel demand and developed plans to introduce smart mobility based on the analysis results. RESULTS : Areas vulnerable to public transportation in Daegu Metropolitan City can be divided into those with low public transportation accessibility and low usage rates, those with good public transportation accessibility but low usage rates, and those with low public transportation accessibility but high usage rates. CONCLUSIONS : Based on the results of this study, it is possible to introduce customized services for each area with poor public transit accessibility, and some of the inconveniences experienced by citizens using public transit are expected to be resolved.
최근 발생되는 재난의 추이를 살펴보면 기후변화에 따른 자연재해 발생빈도가 증가하고 있으며, 이에 따른 피해 규모 추세가 대형화로 변화되고 있다. 대규모로 진행되고 있는 도시화와 고도의 산업화로 인해 도시개발 지역의 확대와 중첩 영향으로 대형 자연 재난이 발생하여 도시시설물에 직접적인 손실이 발생하고 있다. 옥외광고물의 무분별한 설치로 도시의 미관훼손은 몰론 강풍으로 인 한 파손 및 추락 등의 사고가 빈번히 발생하는 실정이다. 이러한 피해는 강풍에 취약한 옥외광고물의 내풍설계 기준의 미비가 가장 큰 요인으로 인식되는데 풍하중 반영한 옥외광고물 설치는 전문지식이 필요한 분야로 중소규모의 옥외광고사업자가 대부분인 국내 현실 과는 괴리가 발생하고 있다. 따라서 본 연구에서는 전국에서 이용할 수 있는 풍하중을 안전성 관점에서 산정하였고, 이를 바탕으로 옥 외광고물 설치 고정자재 수 등을 산정할 수 있는 내풍표준 가이드라인을 제시하였다.