검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 91

        43.
        2003.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        사용후핵연료와 같은 고준위 방사성물질을 취급하는 핫셀 내에서 원격취급장치인 MSM의 작업영역을 벗어난 지역에 위치한 공정장치부품 유지보수공정을 개발하였다. 이를 위하여 대상 핫셀공정인 사용후핵연료 차세대관리공정에 대한 가상목업을 구축하였으며, 구축된 가상목업을 이용하여 MSM 작업영역 및 작업자 시각영역을 분석하고, 그래픽 가상목업의 충돌감지 기능을 이용한 서보 조종기의 경로계획을 수립하였다. 또한, 분석한 결과를 토대로, 서보조종기에 의한 사각지역 내 부품 유지보수 공정을 설정하였으며, 설정된 공정은 그래픽 전산모사를 통하여 검증하였다. 제안된 유지보수 공정은 실제 핫셀공정 수행시 유용하게 활용될 것이며, 그래픽 가상목업은 다양한 핫셀 공정에 대한 분석 및 작업자 훈련 시스템으로 활용하여, 작업 효율성 및 안전성 향상에 기여할 것으로 기대된다.
        4,000원
        44.
        2019.10 서비스 종료(열람 제한)
        이 연구에서는 반복하중을 받는 ㄷ자형 강재 댐퍼의 거동을 평가 한다. 연구에 사용된 강재 항복형 댐퍼는 에너지소산부와 긴결부로 구성된다. 에너지소산부의 단면 크기는 15×20mm이며 폭은 120mm, 높이는 90mm이다. 제조가 간편한 ㄷ자 형태를 가지는 강재 댐퍼는 지진하중을 모사할 수 있는 실험기기에 장착되어 반복하중을 받도록 하였다. 목표변위까지 총 5회의 반복하중 실험을 수행한 결과, 강재의 항복 이후 에너지소산능력이 뛰어난 연성적인 거동을 보였을 뿐만 아니라 반복하중을 수행하는 동안 강도의 저하를 보이지 않음을 확인할 수 있었다.
        45.
        2018.05 서비스 종료(열람 제한)
        Background : The interest in paddy-converted fields to be used as an alternative new farming area for the stable ginseng production is increasing, and made up -32% of the total ginseng cultivation area in Korea in 2014. Therefore, this study examined how soil types and fertilizer regimes influence fatty acid (FA) and vitamin E (Vit-E) variation in 6-years-old ginseng root. Methods and Results : Ginseng variety “Jagyeongjong” was cultivated upland and paddy-converted field, and three organic fertilizers were applied to both fields, at 0, 1, 2, and 4 tons per 1,000 ㎡, prior to the ginseng seedling transplantation. The 37 FAs and 8 Vit-E were analyzed with GC-FID. We observed significant variation in both FA and Vit-E contents owing to the type and quantity of organic fertilizer used in each soil type during cultivation. Unsaturated FAs were approximately 2.7-fold higher in ginseng than in saturated FAs. Linoleic, palmitic, and oleic acids were the most abundant FAs detected in ginseng roots. Additionally, α-tocopherol was the major Vit-E detected. In particular, the increased application of rice straw compost or food waste fertilizer elevated the quantity of nutritionally desirable FAs and bioactive Vit-E in ginseng root. Partial least square-discriminant analysis (PLS-DA) score plots showed that soil type might be the main cause of differences in FA and Vit-E levels in ginseng. Specifically, the PLS-DA model indicated that palmitic acid is a suitable FA marker in determining whether ginseng plants were grown in a paddy-converted field or an upland field. Moreover, linoleic acid levels were highly correlated with α-linolenic acid (r = 0.8374) according to Pearson's correlations and hierarchical clustering analysis. Conclusion : This study investigated how soil type, as well as organic fertilizer type and amount, altered the FA and Vit-E profiles in ginseng roots. Therefore, these preliminary data should be beneficial to ginseng farmers and any industries involved in the production of high quality and nutritional ginseng products.
        46.
        2018.05 서비스 종료(열람 제한)
        Background : Agaricus bisporus mushroom, which originated from Europe, is an edible mushroom with a unique taste and flavor and is the most widely cultivated mushroom type worldwide, particularly because of the relatively high protein, dietary fiber, and vitamin D contents of the fruit body, which have human health benefits like anticancer and DNA damage protection. However, to our knowledge, few studies have been conducted on the ability to discriminate mushroom’s bioactive compounds according to regional production sites. Thus, this study was aimed to examine the regional difference of selected bioactive compounds in of Agaricus bisporus mushroom. Methods and Results : The cultivars (cv.) “Saedo” and “Saehan” obtained from five regions of Korea were measured their phenolics and fatty acids profiling by LC/MS and GC-FID system, respectively. Among 54 targeted phenolics, protocatechuic, p-hydroxybenzoic, caffeic, 2,4-dihydrobenzoic, p-coumaric, and salicylic acids were found in the cv. Saedo and cv. Saehan fruit body. Also, tyrosine and phenylalanine, which are precursor metabolites of phemolics, were also observed in the A. bisporus fruit body. In particular, phenylalanine and p-hydroxybenzoic acid were the most abundant phenolic precusor and metabolite present in the A. bisporus, and was significant with the production regions (p < 0.05). The FA content was significant with the production region, but not much differed (p < 0.05). The n-6 FA including linoleic acid was the major FA in the mushroom, accounting > 70% over total FA content. However, the n-3 FA was the n-6 FA was very minor FA metabolites. Conclusion : These preliminary results can extend knowledge of regional difference of certain targeted bioactive compounds in A. bisporus mushroom produced in Korea, contributing to reliable regional difference with potential broader applications for the international mushroom market.
        47.
        2017.09 KCI 등재 서비스 종료(열람 제한)
        In order to investigate the effect of air temperature reduction on an urban neighborhood park, air temperature data from five inside locations (forest, pine tree, lawn, brick and pergola) depending on surface types and three outside locations (Suwon, Maetan and Kwonsun) depending on urban forms were collected during the summer 2016 and compared. The forest location had the lowest mean air temperature amongst all locations sampled, though the mean difference between this and the other four locations in the park was relatively small (0.2-0.5℃). In the daytime, the greatest mean difference between the forest location and the two locations exposed to direct beam solar radiation (brick and lawn) was 0.5-0.8℃ (Max. 1.6-2.1℃). In the nighttime, the mean difference between the forest location and the other four locations in the park was small, though differences between the forest location and locations with grass cover (pine tree and lawn) reached a maximum of 0.9-1.7℃. Comparing air temperature between sunny and shaded locations, the shaded locations showed a maximum of 1.5℃ lower temperature in the daytime and 0.7℃ higher in the nighttime. Comparing the air temperature of the forest location with those of the residential (Kwonsun) and apartment (Maetan) locations, the mean air temperature difference was 0.8-1.0℃, higher than those measured between the forest location and the other park locations. The temperatures measured in the forest location were mean 0.9-1.3℃ (Max. 2.0-3.9℃) lower in the daytime than for the residential and apartment locations and mean 0.4-1.0℃ (Max. 1.3-3.1℃) lower in the nighttime. During the hottest period of each month, the difference was greater than the mean monthly differences, with temperatures in the residential and apartment locations mean 1.0-1.6℃ higher than those measured in the forest location. The effect of air temperature reduction on sampling locations within the park and a relatively high thermal environment on the urban sampling locations was clearly evident in the daytime, and the shading effect of trees in the forest location must be most effective. In the nighttime, areas with a high sky view factor and surface types with high evapotranspiration potential (e.g. grass) showed the maximum air temperature reduction. In the urban areas outside the park, the low-rise building area, with a high sky view factor, showed high air temperature due to the effect of solar (shortwave) radiation during the daytime, while in the nighttime the area with high-rise buildings, and hence a low sky view factor, showed high air temperature due to the effect of terrestrial (longwave) radiation emitted by surrounding high-rise building surfaces. The effect of air temperature reduction on the park with a high thermal environment in the city was clearly evident in the daytime, and the shading effect of trees in the forest location must be most effective. In the nighttime, areas with high sky view factor and surface types (e.g., grass) with evapotranspiration effect showed maximum air temperature reduction. In the urban areas outside the park, the high sky view factor area (low-rise building area) showed high air temperature due to the effect of solar (shortwave) radiation during the daytime, but in the nighttime the low sky view factor area (high-rise building area) showed high air temperature due to the effect of terrestrial (longwave) radiation emitted surrounding high-rise building surfaces.
        51.
        2017.05 서비스 종료(열람 제한)
        Background : Pachyrhizus erosus (Leguminosae), locally called as “Yam bean” is a traditional medical plant that grows in the tropical and subtropical region. The root of P. erosus is used by the local people to treat insomania, treatment of osteoporosis and extracts of this plant have shown antioxidant activity, immunomodulatory activity, tyrosinase inhibitionby, antitumour properties and cardiovascular benefit. Methods and Results : Free radical scavenging activity was evaluated using α-tocopherol and butylated hydroxy toluene (BHT) as standard antioxidants. The radical scavenging activity was measured using the stable radical 1,1-diphenyl–2-picrylhydrazyl (DPPH) and ABTS assay. Total phenolic content was determined by following Folin-Ciocalteau colorimetric method and Total flavonoids were determined using aluminium chloride calorimetric methods. Phenolic compound concentration and compositions were determined by HPLC-MS/MS system. Seedlings grown under the flourescent light (Fl) exhibited the highest DPPH radical scavenging activity when compared to the plants treated with light emitting diodes (LEDs) and light emitting plasma (LEP). LED-Blue showed the higher DPPH radical scavenging activity and ABTS concentration of PE compared to other LEDs. The accumulation of phenolic compounds increased under different white-LEDs conditions as compared to LEP and FL light conditions. Conclusion : In this study, antioxidant activity and phenolic compound composition of P. erosus was improved by the application of LED and LEP.
        52.
        2017.05 서비스 종료(열람 제한)
        Background : Although ginseng has various bioactive compounds in it, there is lack of study on the variations of bioactive compounds in ginseng according to the cultivation soil and the applied fertilizer types (or amount). Therefore, this study aims to examine the variations of 37 fatty acids (FA) and 8 vitamin E (Vit-E) vitamers in 6-year-old ginseng root cultivated in different soil types with different fertilizers regimes. Methods and Results : The profiling of 37 FAs and 8 Vit-E vitamers in 6-year-old ginseng roots was measured by gas chromatography coupled with a flame ionization detector, and then these results were statistically analyzed with chemometrics. The FA and Vit-E content in ginseng roots varied significantly with respect to soil cultivation conditions due to organic fertilizer types and amounts used. Unsaturated FA in ginseng is approximately 2.7 fold higher than the saturated FA. Linoleic, palmitic, and oleic acids were the most abundant FAs found in the ginseng roots. Also, the major Vit-E vitamer found in ginseng root is α-tocopherol. In particular, the application of rice straw compost or food waste fertilizer was increased to create nutritionally desirable FAs and bioactive Vit-E in ginseng root. In addition, phytonutrient profiling coupled with chemometrics can be used to discriminate the cultivation conditions of ginseng. Conclusion : This study extends our understanding about the variations of FA and Vit-E in ginseng root depending on cultivation conditions. Hence, these results can be useful as basic information for reliable ginseng production containing high amounts of phytonutrients in a paddy-converted field.
        53.
        2017.05 서비스 종료(열람 제한)
        Background : The geographical origin of Panax ginseng Meyer, a valuable medicinal plant, is important to both ginseng producers and consumers in the context of economic profit and human health benefits. We therefore aimed to discriminate between the cultivation regions of ginseng using the stable isotope ratios of C, N, O, and S, which are abundant bio-elements in living organisms. Methods and Results : The C, N, O, and S stable isotope ratios were measured by isotope ratio mass spectrometer, and then these isotope ratios profiling was statistically analyzed with chemometrics. The various isotope ratios found in Panax ginseng roots were significantly influenced by region, cultivar, and the interactions between these two factors (P ≤ 0.0002). In particular, δ18O was lower in ginseng roots grown at high altitudes (r = −0.47), while δ34S was higher in ginseng roots grown close to coastal areas (r = −0.48). Chemometric results provided discrimination between the majorities of different cultivation regions. Conclusion : Our case study extends the understanding about the variation of C, N, O, and S stable isotope ratios in ginseng root depending on cultivation region. Hence, the analysis of stable isotope ratios is a suitable tool for discrimination between the regional origins of ginseng samples from Korea, with potential application to other countries.
        54.
        2017.05 서비스 종료(열람 제한)
        Background : Corrosion is one of the most devastating problems faced by most industries. Mild steel has played a vital role in various fields due to the excellent mechanical properties of mild steel such as low density, high strength-to-weight ratios, good environmental stability, high thermal conductivity, and corrosion resistance. Methods and Results : The total phenolic contents (TPC) and total flavonoid contents (TFC) of the methanolic extract of C. grandiflora and R. verniciflua leaf have been examined, and its corrosion inhibition performance was investigated by weight loss and electrochemical impedance spectroscopy (EIS) and polarization measurements. The surface morphology of mild steel was analyzed by scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDX) and by atomic force microscopy (AFM). The percentage composition of polyphenolic compounds was found to be higher in C. grandiflora and R. verniciflua plant extracts, and it was proved to be a superior, eco-friendly, and anti-corrosive inhibitor for mild steel in 1M of H2SO4. The Tafel polarization studies indicate that the plant extract is a mixed-type inhibitor. Scanning electron microscopy/energy -dispersive X-ray spectroscopy (SEM-EDS), and atomic force microscopy (AFM) studies confirmed the formation of a protective film on the metal surface. The corrosion inhibition of the C. grandiflora and R. verniciflua plant extracts was characterized by Fourier transform infrared (FT-IR), UV-visible spectra, and wide-angle X-ray diffraction (XRD) studies; these show the strong interaction between the metal surface and the inhibitor. Conclusion : The methanolic extract was prepared the two different plants like C. grandiflora, and R. verniciflua was studied the corrosion inhibition on the mild steel specimen in acidic medium through various methods involving weight loss measurements, EIS, and potentiodynamic polarization. The results shows that the C. grandiflora, and R. verniciflua plant extracts illustrate an effective corrosion inhibitor for mild steel with good anticorrosion properties in acidic environmen
        55.
        2016.10 서비스 종료(열람 제한)
        Background : Despite the presence of various bioactive compounds in ginseng, there is lack of study on the variations of bioactive compounds in ginseng according to the cultivation of soil and the applied fertilizer types (or amount). Therefore, this study aims to examine the variations of 37 fatty acids (FA) and 8 vitamin E (Vit-E) vitamers in 6-year-old ginseng root cultivated in different soil types with different fertilizers regimes. Methods and Results : The profiling of 37 FAs and 8 Vit-E vitamers in 6-year-old ginseng roots was measured by gas chromatography coupled with a flame ionization detector, and then these results were statistically analyzed with chemometrics. The FA and Vit-E content in ginseng roots varied significantly with respect to soil cultivation conditions due to organic fertilizer types and amounts used. Unsaturated FA in ginseng is approximately 2.7 fold higher than the saturated FA. Linoleic, palmitic, and oleic acids were the most abundant FAs found in the ginseng roots. Also, the major Vit-E vitamer found in ginseng root is α -tocopherol. In particular, the application of rice straw compost or food waste fertilizer was increased to create nutritionally-desirable FAs and bioactive Vit-E in ginseng root. In addition, phytonutrient profiling coupled with chemometrics can be used to discriminate the cultivation conditions of ginseng. Conclusion : This preliminary study extends our understanding about the variations of FA and Vit-E in ginseng root depending on cultivation conditions. Hence, these results can be useful as basic information for reliable ginseng production containing high amounts of phytonutrients in a paddy-converted field.
        56.
        2016.10 서비스 종료(열람 제한)
        Background : Despite the presence of various bioactive compounds in ginseng, there is lack of study about the phenolic metabolites in ginseng especially depending on the cultivation soil and the fertilizer types. Therefore, this study aims to develop an (-)ESI-LC-MS/MS analytical method for the measurement of selected phenolic compounds in the ginseng root. Methods and Results : Total phenol content in ginseng root was measured with the Folin-Ciocalteau method using UV/Vis spectrophotometer. Then, the 56 selected phenolic metabolites in ginseng root were measured with the (-)ESI-LC-MS/MS. The brief LC-MS/MS analytical conditions were as follows; Thermo Scientific Syncronis C18 HPLC Column (250 × 4.6 mm, 5 μm) was used. Optimized instrument settings were as follows: Curtain gas 20 psi, collision gas 2 psi, ion spray voltage –4500 V, nebulizer gas 40 psi, heating gas 70 psi, and its temperature 350℃. Total phenol content was higher in the ginseng cultivated in the paddy-converted field than that in upland. In particular, the total phenol content was about 6% decreased in the ginseng root cultivated with the food waste fertilizer compared to the control (p < 0.05). Six phenolic constituents including caffeic, chlorogenic, p-coumaric, ferulic, gentisic, and salicylic acids were found in the ginseng root by using the LC-MS/MS in MRM (multiple reaction monitoring) Mode. These six phenolic compounds occupied approximately 20% of the total phenol content measured in the corresponding ginseng root. The chlorogenic acid was the most abundant phenolic metabolite found in the ginseng root, accounting for ≥ 95% of the sum of six phenolic compounds, in this study. Conclusion : This preliminary study can be useful for the study on content and composition of phenolic metabolites in ginseng root with the aspect of metabolomics. We plan to further optimize the LC-MS/MS analytical method and then provide the extended understanding on the phenolic metabolism in the ginseng root with respect to the ginseng cultivation conditions.
        57.
        2016.10 서비스 종료(열람 제한)
        Background : The natural stable isotope ratio of common bio-elements like carbon (C), nitrogen (N), oxygen (O), or sulfur (S) varies with diverse isotope fractionation processes in nature. Therefore, measuring the variation of these stable isotope ratios in ginseng roots can be a feasible tool to discriminate the geographical origins of ginseng in Korea. Methods and Results : The 3-year-old six Korean ginseng cultivars were cultivated at the five regions in Korea, and then used for measuring the stable isotope ratios of C, N, O, and S by isotope ratio mass spectrometry (IRMS). The mean C, N, O, and S stable isotope ratio values in the ginseng roots significantly differed according to the cultivation regions (p < 0.05). However, these isotope ratios in ginseng roots had relatively weak discriminative power against to the ginseng cultivars at each cultivation region. The interaction of the cultivation region and ginseng cultivar type also significantly affected to the C, N, O, and S stable isotope ratio in ginseng roots (p < 0.0001). The two-dimensional plots associated with the N stable isotope ratio can effectively separate the ginseng roots in Jinan compared to those in the other regions. The partial least squares-discriminant analysis showed more significant separation between ginseng geographical origins compared to the principal component analysis. Conclusion : Our findings improve our understanding of how the isotope composition of ginseng roots varies with respect to cultivation regions and cultivars, and suggest that the analysis of the stable isotope ratios combined with chemometrics can be used as a feasible tool to discriminate geographical origin of ginseng in Korea.
        58.
        2016.04 서비스 종료(열람 제한)
        This study presented the seismic performance of weir structures with infinite foundations subjected to seismic ground motions, rather than finite soil foundation to avoid the reflection of seismic wave propagation at the mesh boundaries. The analytical model of weir structures was developed in ABAQUS platform and then the seismic performance of concrete weir structure was evaluated through design response spectrum (KBC 2009). It was revealed that the maximum stresses obtained from infinite models was significantly increased, in comparison to the finite models.
        60.
        2015.10 서비스 종료(열람 제한)
        the primary objective of this research is to reduce the damage of critical frame structures such as hospitals and schools during and after an earthquake. this study develop the infill panel to allow smaller shear deformation with sliding of the specific element in the panel. As a result, the side sway was significantly reduced in the structure with infill panel, in comparison to the steel frame structure without infill panel during the experimental test
        1 2 3 4 5