검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 2,509

        64.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A new spore-less cultivar Lentinula edodes ‘Daedam’ was bred from monokaryotic strains of ‘LE15401-24’ and ‘LE192118-10’. The optimum temperature for mycelial growth of ‘Daedam’ on potato dextrose agar was 22~25oC. Total cultivation period of the new cultivar, from inoculation to its first harvest, was 134 days, similar to that of the control cultivar ‘Hwadam’. Total yield of ‘Daedam’ was 222g per 3kg substrate, and was lower than that of control cultivar(266.0g). The fruiting body of ‘Daedam’ had a thick and small pileus and a longer stem compare to control cultivar. As a result of a analyzing the productivity of ‘Daedam’ on the different substrate types, the biological efficiency was 26.7% in the 1.2kg cylindrical substrate(CS), which was higher than that of the 3kg rod-type substrate(RS). 'Daedam' had a similar yield compared to 'Hanacham' in first fruiting body production, but the cultivation period was 40 days shorter. Therefore, 'Daedam' can only harvest fruiting bodies once, it is thought that it can be used as spore-less oak mushroom cultivar for short-term cultivation instead of 'Hanacham' in mushroom farms.
        4,000원
        65.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to reduce the phenomenon of the biased cultivation of certain mushroom varieties and to develop a competitive variety of Pleurotus nebrodensis. We have collected and tested characteristics of genetic resources from domestic and overseas varieties since 2015. We bred the domestic variety ‘Boram’. The optimal temperature was 26~29oC for mycelial growth and 15~18oC for fruit body growth temperature. This variety was similar to the control variety (Uram) in terms of the number of cultivation days and yield per bottle. The shape of the new cultivar was round, whereas that of the control group was spatula-like. The yield was 181.1 g/bottle, which was statistically similar to that of the control variety. When incubating the parent and control varieties, the replacement line was clear. Moreover, polymerase chain reaction analysis of mycelial DNA resulted in different band patterns between the parent and control varieties, confirming the hybrid species.
        4,000원
        66.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this paper, a dynamic centrifuge model test was conducted on a 24.8-meter-deep excavation consisting of a 20 m sand layer and 4.8 m bedrock, classified as S3 by Korean seismic design code KDS 17 10 00. A braced excavation wall supports the hole. From the results, the mechanism of seismically induced earth pressure was investigated, and their distribution and loading points were analyzed. During earthquake loadings, active seismic earth pressure decreases from the at-rest earth pressure since the backfill laterally expands at the movement of the wall toward the active direction. Yet, the passive seismic earth pressure increases from the at-rest earth pressure since the backfill pushes to the wall and laterally compresses at it, moving toward a passive direction and returning to the initial position. The seismic earth pressure distribution shows a half-diamond distribution in the dense sand and a uniform distribution in loose sand. The loading point of dynamic thrust corresponding with seismic earth pressure is at the center of the soil backfill. The dynamic thrust increased differently depending on the backfill's relative density and input motion type. Still, in general, the dynamic thrust increased rapidly when the maximum horizontal displacement of the wall exceeded 0.05 H%.
        4,000원
        67.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Recently, there has been an increasing demand for independent suspension systems in commercial vehicles, and various researches related to this trend are currently underway. In this study, as part of an effort to localize the independent suspension system for commercial vehicles, a preceding study was conducted to convert the existing forging process into a casting process. The structural stability of the developed product was evaluated by performing stress analysis on both forging and casting materials. In order to compensate for the low yield characteristics of the casting material, design improvements were made to lower the maximum stress level based on numerical simulations.Additionally, Lightweight design was performed, capitalizing on the inherent design flexibility offered by casting products. As a result, it was confirmed that the developed product exhibited similar stress characteristics level to the existing product, along with a weight reduction of approximately 5%.
        4,000원
        68.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated the antioxidant characteristics of sweet potato according to different plant parts and drying methods. The sweet potato plant parts were divided into root tubers, stems, stalks, leaves, and tips, and the drying methods were freeze-drying and hot air drying. Total polyphenol and flavonoid contents and radical scavenging activity of the sweet potato plant parts were significantly different depending on the plant parts and drying methods. The total polyphenol content of freeze-dried sweet potato leaves and tips were 52.76 and 46.19 mg chlorogenic acid equivalents/g sample, and the total flavonoid contents were 222.47 and 214.12 mg quercetin equivalents/g sample, respectively, and decreased with hot air drying. DPPH radical scavenging activity was higher in freeze-drying than hot air drying and was significantly different depending on the plant parts. The ABTS radical scavenging activity of freeze-dried sweet potato leaves and tips were 43.48 and 44.68 mg Trolox equivalents/g sample, respectively, and decreased with hot air drying. Therefore, additional studies on the functionality of using by-products from sweet potato cultivation are needed.
        4,000원
        69.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study developed and evaluated a load cell-based automatic weighing system for the automated harvesting of laver (Porphyra tenera) in seaweed aquaculture. The current manual harvesting process was compared with the load cell-based automated system, and quantitative measurements of time, distance, and weight were conducted. The results demonstrated that the load cell-based system reduced the unloading time and increased the throughput compared to the manual method. In addition, statistical analysis confirmed that there was no significant difference from the mean in the weight measurement obtained using the load cell-based system. Based on these findings, the load cell-based automatic weighing system holds potential for efficient production and transactions in laver cultivation, contributing to cost reduction and improving the quality of life for aquaculture workers.
        4,000원
        70.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The aim of this study was to compare the antioxidant activities and functional contents of Korean conventional and Chinese seed gingers from the Jeollabuk-do Wanju and Chungcheongnam-do Seosan regions. Ginger samples were subjected to steaming treatments for different durations (2–8 h) at 121oC using an autoclave. The antioxidant activity was evaluated by measuring total polyphenol and flavonoid contents and ABTS and DPPH radical scavenging activities, while functional ingredient contents were analyzed for gingerols and shogaols. The results showed that Wanju conventional seed ginger (WO-2) had the highest total polyphenol (85.24 mg GAE/g) and flavonoid (98.14 RE/100 g) contents, surpassing that of the control in all steamed groups at 6 h. ABTS radical scavenging activity showed a strong correlation with total polyphenol and flavonoid contents. The control groups indicated that Korean conventional seed ginger had 1.0–1.3 times higher gingerol contents compared to Chinese seed ginger. Furthermore, the content of shogaols, considered major functional ingredients, increased significantly with longer steaming durations, reaching the highest content (1,793 mg/kg) at 8 h, which was 1.0–1.8 times higher in Korean conventional seed ginger than that in Chinese seed ginger. These experiments provide valuable data supporting the excellence of Korean conventional seed ginger in the future.
        4,000원
        71.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A total of 100 commercially available olive oil products were analyzed for 179 pesticide residues using gas chromatography-tandem mass spectrometry (GC/MS/MS). The olive oil samples were mixed with organic solvents, centrifuged and frozen to remove fat, and pesticide residues were analyzed using the “quick, easy, cheap, effective, rugged, and safe” (QuEChERS) method. The determination coefficient (R2) of the analysis method used in this study was ≥0.998. The detection limit of the method ranged 0.004–0.006 mg/kg and its quantitative limit ranged 0.012–0.017 mg/kg. The recovery rate (n=5) measured at the level ranging 0.01–0.02, 0.1, and 0.5 mg/kg ranged 66.8– 119.5%. The relative standard deviation (RSD) was determined to be ≤5.7%, confirming that this method was suitable for the "Guidelines for Standard Procedures for Preparing Food Test Methods". The results showed that a total of 151 pesticides (including difenoconazole, deltamethrin, oxyfluorfen, kresoxim-methyl, phosmet, pyrimethanil, tebuconazole, and trifloxystrobin) were detected in 64 of the 100 olive oil products. The detection range of these pesticide residues was 0.01–0.30 mg/kg. The percentage acceptable daily intake (%ADI) of the pesticides calculated using ADI and estimated daily intake (EDI) was 0.0001–0.1346, indicating that the detected pesticides were present at safe levels. This study provides basic data for securing the safety of olive oil products by monitoring pesticide residues in commercially available oilve oil products. Collectively, the analysis method used in this study can be used as a method to analyze residual pesticides in edible oils.
        4,000원
        72.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : This paper proposes an artificial neural network (ANN)-based real-time traffic signal time design model using real-time field data available at intersections equipped with smart intersections. The proposed model generates suitable traffic signal timings for the next cycle, which are assumed to be near the optimal values based on a set of counted directional real-time traffic volumes. METHODS : A training dataset of optimal traffic signal timing data was prepared through the CORSIM Optimal Signal Timing program developed for this study to find the best signal timings, minimizing intersection control delays estimated with CORSIM and a heuristic searching method. The proposed traffic signal timing design model was developed using a training dataset and an ANN learning process. To determine the difference between the traditional pre-time model primarily used in practice and the proposed model, a comparison test was conducted with historical data obtained for a month at a specific intersection in Uiwang, Korea. RESULTS : The test results revealed that the proposed method could reduce control delays for most of the day compared to the existing methods, excluding the peak hour periods when control delays were similar. This is because existing methods focus only on peak times in practice. CONCLUSIONS : The results indicate that the proposed method enhances the performance of traffic signal systems because it rapidly provides alternatives for all-day cycle periods. This would also reduce the management cost (repeated field data collection) required to increase the performance to that level. A robust traffic-signal timing design model (e.g., ANN) is required to handle various combinations of directional demands.
        4,000원
        73.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : This study aims to develop and validate timing transition techniques for real-time traffic signal operations, departing from conventional methods based on past commuting traffic patterns. METHODS : In this study, we propose two traffic signal transition techniques that can perform transitions while minimizing disruptions within a short period. The Proposed 1 technique involves an unconditional transition within one cycle and allows for the allocation of offset changes to both the coordinated and non-coordinated phases. The Proposed 2 technique performs transitions within 1-2 cycles based on the offset change rate and considers the non-coordinated phase for allocating offset changes. RESULTS : Functional improvements of the proposed techniques were validated. For validation, simulated traffic signal transition scenarios were created, and a comparative analysis of the transition techniques was performed based on the selected analysis approaches. The results showed that the Proposed 1 technique exhibited the lowest delay during the approximated saturated transitions, whereas the Subtract technique showed the lowest delay during the non-saturated transitions. CONCLUSIONS : These findings emphasize the importance of selecting and applying appropriate transition techniques tailored to individual traffic scenarios. The proposed transition techniques provide valuable insights for improving real-time traffic signal operations, and contribute to the overall efficiency and effectiveness of traffic management in highway corridors.
        4,000원
        74.
        2023.07 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        담도 스텐트가 인접한 담도 주위 혈관에 손상을 주어 혈액 담즙증을 유발하거나 스텐트 제거 시 손상으로 발생할 수 있다고 드물게 보고된다. 스텐트 제거 시 활력징후가 불안정 해질 정도의 혈액 담즙증이 생기는 경우, 혈관조영술을 시행 하기 전 구조 요법으로 피막형 팽창성 금속 스텐트의 압박 효과를 통한 지혈을 기대하고 삽입할 수 있다. 본 두 증례는 간문부 담관암 환자에서 간문부 폐색에 대해 삽입한 담도 스텐트 그리고 간세포암종 환자에서 간동맥 화학색전술 이후 동반된 간농양의 내배액 목적으로 삽입한 담도 스텐트를 각각 교체 목적으로 제거 후 급격히 악화된 대량의 혈액 담즙증을 피막형 팽창성 금속 스텐트를 삽입하여 성공적으로 치료된 사례이다. 한편, 해당 상황에선 정확한 출혈 위치를 알기 어려워 예상되는 출혈 위치를 포함할 수 있을 만큼 높은 위치에 스텐트를 삽입해야 하며 적절한 위치에 삽입되었더라도 지혈이 되지 않을 수 있기에 일시적인 방안이며 스텐트 자체의 한계점들도 있다. 따라서, 기존의 스텐트 제거 시 혈액 담즙증이 발생할 수 있음을 인지하고, 그중 출혈의 위험성이 높은 환자에서는 제거 전 영상 검사를 고려해야 하며 출혈이 발생한 뒤 스텐트를 통해 성공적으로 지혈을 시행했더라도 출혈 및 가성동맥류와 같은 혈관 기형의 확인을 위한 영상 검사를 고려해야한다.
        4,000원
        75.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 시엽의 기능성 화장품 소재로서의 활용 가능성을 평가하기 위해 항산화와 인 간섬유아세포인 CCD-986sk 세포에서의 항주름 효과를 알아보았다. 전자공여능 측정, ABTS+ radical 소거능 측정을 통해 항산화 활성을 확인한 결과, 시엽은 1,000 μg/ml 농도에서 대조군인 ascorbic acid 와 농도 의존적으로 유사한 항산화 활성을 보였다. Elastase 저해 활성 측정, Collagenase 저해 활성 측 정을 통해 항주름 효과를 확인한 결과, 시엽은 1,000 μg/ml 농도에서 대조군인 epigallocatechin gallate 와 농도 의존적으로 유사한 항주름 효과를 나타내었다. UVB로 유도된 CCD-986sk 세포 내 pro-collagen type I의 합성률과 MMP-1의 저해률을 측정한 결과 대조군인 EGCG는 20 μg/ml에서 90.2%, 시엽은 30 μg/ml에서 88.5%의 pro-collagen 합성률을 보였다. 또한 EGCG 20 μg/ml와 시엽 30 μg/ml에서 각각 33.0%, 40.8%의 MMP-1 저해율을 확인하였다. Western blot을 통하여 시엽의 pro-collagen type I과 MMP-1의 단백질 발현량을 측정한 결과 UVB 단독군 대비 시엽을 함께 처리했 을 때 pro-collagen type I의 단백질 발현량이 증가하고 MMP-1의 단백질 발현량이 감소하는 것을 확 인하였다. 위 실험결과에 따라 시엽이 UVB 자극에 의한 광노화를 예방하고 항산화, 항주름 효과가 있음 을 확인하여 화장품의 천연물 소재로서의 이용이 기대된다.
        4,500원
        76.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, we investigated the effect of the extracts of Cyrtomium fortunei J.Sm. (CFJ) on lipopolysaccharide (LPS) induced inflammation in mouse BV-2 microglial cells. Nitric oxide (NO) production and cell viability were measured using the Griess reagent and the (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) (MTT) assay. Inflammatory cytokines were detected by quantitative polymerase chain reaction (qPCR) in BV-2 microglial cells with and without CFJ extracts. Subsequently, mitogen-activated protein kinases (MAPKs) and antioxidant markers were assessed by western blot analysis. It was found that the CFJ extract significantly decreased the production of pro-inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor [TNF]-, and IL-1) and NO in BV-2 microglial cells that were stimulated with LPS. In addition, the expression levels of the phosphorylation of the MAPK family (p38, c-Jun N-terminal kinases [JNK], and extracellularsignal regulated kinase [ERK]) were reduced by CFJ. Also, treatment with CFJ significantly increased the activities of superoxide dismutase type 1(SOD1) and Catalase in BV-2 microglial cells. Our results indicate that CFJ has a potent suppressive effect on the pro-inflammatory responses of activated BV-2 microglia. Therefore, CFJ has the potential to be an effective treatment for neurodegenerative diseases, as it can inhibit the production of inflammatory mediators in activated BV-2 microglial cells.
        4,000원
        77.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aims to analyze the cost of climate change damages to laver and sea mustard aquaculture, which are considered to be highly vulnerable to climate change in Korea. For this purpose, the correlation between aquaculture production and climate factors such as water temperature, salinity, air temperature, and precipitation was estimated using a panel regression model. The SSP scenario was applied to predict the changes in production and damage costs due to changes in future climate factors. As a result of the analysis, laver production is predicted to decrease by 18.0-27.2% in 2050 and 20.6-61.6% in 2100, and damage costs are predicted to increase from 29.7-50.8 billion KRW in 2050 to 35.7-116.1 billion KRW in 2100. Sea mustard production is projected to decrease by 24.5-37.2% in 2050 and 24.0-34.5% in 2100, with similar damage costs of 41.1-61.8 billion KRW and 41.1-58.6 billion KRW, respectively. These damage costs are expected to occur in the short term as damage caused by fishery disasters such as high temperatures, and in the long term as a decrease in production due to changes in aquaculture sites. Therefore, measures such as strengthening the forecasting system to prevent high-temperature damage, developing high-temperature-resistant varieties, and relocating fishing grounds in response to changes in aquaculture sites will be necessary.
        4,600원
        79.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : This study predicts the concentration of suspended road dust (PM10) by analyzing meteorological, traffic, and atmospheric environmental data acquired at various angles, and attains a comprehensive understanding of the influencing factors of suspended road dust. METHODS : Experimental field methods were applied and statistical analyses were conducted. Field experiments were conducted using a vehicle-based measurement of suspended dust (PM10) to measure its concentration at the measurement site while maintaining a constant driving vehicular speed. Statistical analysis demonstrated the effects of the concentration of suspended dust on changes in meteorological and environmental factors and lanes per traffic volume at the time of measurement. Finally, a multiple linear regression model was applied to identify the factors which affected the generation of suspended dust. RESULTS : The analysis of suspended road dust concentrations according to the lanes per traffic volume and environmental factors showed that suspended dust concentrations increased at increasing driving speeds. In addition, the background concentration at the monitoring station was higher at high-wind speeds (>3.0 m/s) than at low-wind speeds (<1.6 m/s), but the suspended dust concentrations were higher at low-wind speeds. During the temperature inversion period from evening to morning, the suspended effects of traffic and meteorological factors were greater than the background concentration at the station. Multiple linear regression analysis showed that excluding yellow-dust days, which are known to affect atmospheric pollution levels, the accuracy of the model improved and resulted in increases in background PM10, vapor pressure, sea-level pressure, visibility, after-rainfall time, and in decreases in insolation and precipitation during low-wind speed conditions. CONCLUSIONS : At low-wind speeds, 5 days after rain, and when the relative humidity was higher than 72%, suspended dust was found to be higher than atmospheric PM10 concentration and may increase at increasing driving speeds and section lane traffic volumes. However, the volume of measured data in this study is limited to determining the patterns of suspended dust, as the silt loading of the operational road or the effects of prominent variables were not considered in this study. However, we identified prominent factors related to road-suspended dust for real-time road-dust predictions.
        4,200원
        80.
        2023.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Laver aquaculture, which occupies a large proportion in the aquaculture industry in Korea, is still highly dependent on human labor. Therefore, it is necessary to study the development of an automatic system to improve the working environment and increase the efficiency of aquaculture production systems. The purpose of this study is to evaluate the economic feasibility of an improved system in a study for the loading-unloading and automatic weighing systems in laver aquaculture industry. Economic analysis of the developed unloading and automatic weighing system were implemented under various conditions to calculate more accurate benefits and costs. As a result of this study, the economic feasibility was found to be very high in the three models: net present value (NPV), benefit-cost ratio (B/C), internal rate of return (IRR). Moreover, the results of sensitivity analysis showed that the economical efficiency of the automatic loading, unloading, and weighing system in laver aquaculture was very high.
        4,000원
        1 2 3 4 5