• 한국항해항만학회지
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• 제33권9호
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• pp.603-608
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• 2009

In this paper, a 3m-class free running model ship will be introduced with its manoeuvring performance experiments. The results of turning circle test and zig-zag test will be explained. The developed system are equipped with GPS, main control computer, wireless LAN, IMU (Inertial Measurement Unit), self-propulsion propeller and driving rudder. Its motion can be controlled by RC (Radio Control) and wireless LAN from land based center. Automatic navigation is also available by pre-programmed algorithm. The trajectory of navigation can be acquired by GPS and it provides us with important data for ship's motion control experiments. The results of manoeuvring performance experiment have shown that the developed free running model ship can be used to verify the test of turning circle and zig-zag. For next step, other experimental researches such as ship collision avoidance system and automatic berthing can be considered in the future.

• 동아시아식생활학회지
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• 제12권6호
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• pp.566-573
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• 2002

In order to obtain the basic data fer the processing adaptability of Korean figs(Ficus carica L.), physicochemical analyses were carried out with Korean common type figs in the different ripening stages. Moisture contents decreased, but the contents of protein, fat carbohydrate and soluble solids increased according to the ripening of fruits. K was detected as the most abundant one of all the minerals and Ca, Mg, Na, Fe, Mn, Zn and Cu were the next in order. The mineral contents decreased slightly with ripening. Especially, Ca, Mg, U, Fe and Zn were higher in the unripened H stage figs. The antioxidative activity was assayed with water and methanol extracts from ripened figs by the DPPH radical scavenging ability. The antioxidative activities of Korean figs were relatively high and increased in a dose dependent manner. The methanol extract showed the higher antioxidative activity than the water one. Therefore, the methanol was the better solvent than water for the antioxidative compounds. These results suggested that Korean figs are relatively the good sources of minerals, especially the Ca and the antioxidative compounds.

• 대한기계학회논문집B
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• 제34권5호
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• pp.523-529
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• 2010

Micro actuator의 동력원으로 박테리아 주화성을 기반으로 한 편모박테리아 운동은 널리 연구되고 있다. 본 연구에서는 마이크로입자 추적유속계($\mu$-PTV)를 이용하여 박테리아 주화성에 의해 추진되는 형광입자의 움직임을 분석하였다. 일반적으로 활발한 운동성을 지니고 있는 편모 박테리아 중 Serratia marcescens가 배양액속에서 형광 폴리스티렌 미세입자 표면에 자발적으로 붙게 된다. 박테리아가 부착된 미세입자를 고형화된 화학적 유인물질 L-aspartate가 담겨져 있는 유체 속으로 주입하고, 시간에 따라 입자들이 서서히 L-aspartate가 높은 농도를 가지는 구역으로 이동하는 것을 관찰하였다. 본 연구의 결과로 편모박테리아가 micro actuator의 효율적인 동력원 개발에 적용될 수 있는 가능성을 제시하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권5호
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• pp.275-280
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• 2002

In order to control glucose concentration during fed-batch culture for antibiotic production, we applied so called “software sensor” which estimates unmeasured variable of interest from measured process variables using software. All data for analysis were collected from industrial scale cultures in a pharmaceutical company. First, we constructed an estimation model for glucose feed rate to keep glucose concentration at target value. In actual fed-batch culture, glucose concentration was kept at relatively high and measured once a day, and the glucose feed rate until the next measurement time was determined by an expert worker based on the actual consumption rate. Fuzzy neural network (FNN) was applied to construct the estimation model. From the simulation results using this model, the average error for glucose concentration was 0.88 g/L. The FNN model was also applied for a special culture to keep glucose concentration at low level. Selecting the optimal input variables, it was possible to simulate the culture with a low glucose concentration from the data sets of relatively high glucose concentration. Next, a simulation model to estimate time course of glucose concentration during one day was constructed using the on-line measurable process variables, since glucose concentration was only measured off-line once a day. Here, the recursive fuzzy neural network (RFNN) was applied for the simulation model. As the result of the simulation, average error of RFNN model was 0.91 g/L and this model was found to be useful to supervise the fed-batch culture.

• 대한기계학회논문집A
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• 제35권5호
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• pp.567-574
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• 2011

알미늄 압출재는 고속열차의 경량화를 위하여 기존의 주름강판을 대체하여 널리 사용된다. 알미늄 압출재는 고속열차 적층재 가운데 가장 큰 차음 기여도를 보이나, 동일한 중량의 평판과 비교할 때, 국부공진 주파수 대역에서 투과손실이 크게 떨어진다. 이 연구에서는 차세대 400km/h급 고속철도 차량용 알미늄 압출재를 대상으로 차음 문제를 검토하고, 차음성능의 향상 방안을 제시한다. 코어 구조를 변경시켜 국부공진 대역을 높이고, 우레탄 폼을 코어에 충진시킬 때의 차음성능 향상효과를 실험적으로 확인한다. 최종적으로 제시된 방법이 바닥 적층재의 총 투과손실을 어느 정도 개선시키는가를 평가한다.

• Journal of Dental Anesthesia and Pain Medicine
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• 제22권1호
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• pp.11-18
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• 2022

Background: The vasoconstrictive effect of epinephrine in local anesthetics affects the heart, which leads to hesitation among dentists in injecting local anesthetics into patients with cardiovascular disease. Due to its vasoconstrictive effects, the present study investigated the effects of vasopressin administration on cardiac function in rats. Methods: Experiment 1 aimed to determine the vasopressin concentration that could affect cardiac function. An arterial catheter was inserted into the male Wistar rats. Next, 0.03, 0.3, and 3.0 U/mL arginine vasopressin (AVP) (0.03V, 0.3V, and 3.0V) was injected into the tongue, and the blood pressure was measured. The control group received normal saline only. In Experiment 2, following anesthesia infiltration, a pressure-volume catheter was placed in the left ventricle. Baseline values of end-systolic elastance, end-diastolic volume, end-systolic pressure, stroke work, stroke volume, and end-systolic elastance were recorded. Next, normal saline and 3.0V AVP were injected into the tongue to measure their effect on hemodynamic and cardiac function. Results: After 3.0V administration, systolic blood pressures at 10 and 15 min were higher than those of the control group; they increased at 10 min compared with those at baseline. The diastolic blood pressures at 5-15 min were higher than those of the control group; they increased at 5 and 10 min compared with those at baseline. The preload decreased at 5 and 10 min compared to that at baseline. However, the afterload increased from 5 to 15 min compared with that of the control group; it increased at 10 min compared with that at baseline. Stroke volume decreased at 10 and 15 min compared with that of the control group; it decreased from 5 to 15 min compared with that at baseline. Stroke work decreased from 5 to 15 min compared with that of the control group; it decreased from 5 to 15 min compared with that at baseline. Conclusion: Our results showed that 3.0 U/mL concentration of vasopressin resulted in increased blood pressure, decreased stroke volume and stoke work, decreased preload and increased afterload, without any effect on myocardial contractility.

• The Korean Journal of Pain
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• 제14권1호
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• pp.61-67
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• 2001

Background: Usually, lumbar epidural block is performed on the $L_{3-4}$ interspace. This study was designed to evaluate the analgesic efficacy and shortening of labor duration comparing the $L_{1-2}$ and $L_{3-4}$ interspace epidural blocks in nulliparous normal vaginal deliveries and then investigates side effects following the blocks. Methods: Eighty healthy nulliparous women were divided into two groups, $L_{1-2}$ (n = 40) and $L_{3-4}$ (n = 40). Epidural blocks, lumbar epidural block were performed at the $L_{1-2}$ and $L_{3-4}$ interspace with a catheter advancing 3 cm cephalad. The initial dose of 12 ml (0.167% bupivacaine, fentanyl $50{\mu}g$ and clonidine $75{\mu}g$) was injected epidurally at 4 cm dilatation of cervix and severe pain of labor. If a visual analogue scale (VAS) score was more than 4 points, an additional dose was administered epidurally using the same volume as the above mentioned, but with the exception that the bupivacaine was diluted to 0.1 percentage. The maternal blood pressure, pulse rate, respiration rate and fetal heart rate were measured at 10 min intervals for the first 30 min, at 15 min interval for the next 30 min and at 30 min interval for the last one hour following the blocks. The duration of the first (active) and second stages of labor was counted and the neonatal Apgar score was recorded at one and five min after delivery. The degree of motor block, pruritus, nausea and vomiting were also noted. Results: The patients in group $L_{1-2}$ had lower pain scores than group $L_{3-4}$ at 5, 20, 30, 60 mins. The duration of 1st and 2nd labor stage in the $L_{3-4}$ epidural block were $272{\pm}33.5$ min, $49.2{\pm}27.4$ min respectively but those in the $L_{1-2}$ epidural block were $253.5{\pm}32.5$ min, $37.3{\pm}22.3$ min, respectively. Conclusions: We concluded the analgesic efficacy and shortening of labor duration in $L_{1-2}$ epidural block was better than those in $L_{3-4}$ epidural block. Maternal hemodynamic change, motor block. pruritus, nausea, vomiting and Apgar score showed no significant differences between the two groups.

• 한국주거학회논문집
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• 제22권5호
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• pp.29-36
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• 2011

The inconsistent city planning damaged the city's landscape & identity, the old days. Nowadays the central and local governments are interested in the city's landscape design for residents, economic reason, etc. Color is most efficient one of design elements to improve a city landscape. So to establish the uniqueness and beauty of Gunsan city landscape, this study was performed to find out Gunsan landscape colors to survey the landscape color, by priority. There are nature environment of sea, river, reservoir, mountains and plain and artificial environment of buildings used japanese occupation period, them in early modern era and modern things. It found out the color palette has extracted from the present colors in the city landscape. There were mostly colors with low chroma, middle value and the next thing was them with high value. The blue among hue was strong. The Chroma was very low to be concentrated in $L^*$ axis. So achromatic color or blue/green of middle value and low chroma were recommended for dominant color and the similar color of former color was good for assort color in Gunsan city landscape.

• 대한전자공학회논문지SD
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• 제38권5호
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• pp.357-366
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• 2001

본 논문에서는 높은 회절 효율과 균일도를 갖는 컴퓨터 생성 홀로그래픽 디퓨저를 수정된 반복 푸리에 변환 알고리즘으로 설계하였다. 컴퓨터 생성 홀로그래픽 디퓨저를 설계하기 위한 새로운 방법으로 위상형 홀로 그램들을 대칭, 결합시킴으로서 계산시간을 감소시켰고 재생되는 신호 영역을 확장하였다. 설계한 16 위상형 홀로그래픽 디퓨저는 85.20%의 높은 회절 효율과 2.43%의 균일도, 18.97［㏈］의 평균 신호대 잡음비를 나타내었다. 또한, 컴퓨터 생성 홀로그래픽 디퓨저와 128 단계를 갖는 유사 랜덤 위상 디퓨저를 회절 효율과 균일도 측면에서 비교하였고, 홀로그래픽 디퓨저와 차세대 디스플레이용 소자로서 유용하게 이용될 수 있음을 제시하였다.

• 한국식품영양학회지
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• 제30권2호
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• pp.312-318
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• 2017

Aloe-emodin (AE) is the major bioactive component in aloe and known to exhibit anti-inflammatory activities. However, it has not been elucidated whether its anti-inflammatory potency can contribute to the elimination of obesity. The aim of the current study is to investigate the effect of AE on toll-like receptor 4 (TLR4) pathways in the presence of lipopolysaccharide (LPS) in 3T3-L1 adipocytes. 3T3-L1 adipocytes were treated with AE ($0-20{\mu}M$) for one hour, followed by LPS treatment for 30 min and then, adipokine mRNA expression levels were measured. Next, TLR4-related molecules were measured in LPS-stimulated 3T3-L1 adipocytes. AE significantly decreased the mRNA expression of the tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) in a dose-dependent manner. Moreover, AE suppressed TLR4 mRNA expression. Further study showed that AE could suppress the nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) and phosphorylation of extracellular receptor-activated kinase (pERK). The results of this study suggest that AE directly inhibits $TLR4/NF-{\kappa}B/ERK$ signaling pathways and decreases the inflammatory response in adipocytes.