• 한국염색가공학회지
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• 제27권4호
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• pp.334-339
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• 2015

Polyketone fiber, a newly developed high strength fiber, has a tenacity and modulus similar to the paramid fiber, and can be used for reinforcing mechanical rubber goods(MRG), such as tires, hoses, and technical textiles. In addition, aliphatic polyketone, which has excellent strength, modulus, chemical stability and reasonable price, is being developed only in South Korea. It will be expected for replacement of super fiber such as aramids and increasing the technical textile market share. This paper surveys the mechanical properties of polyketone fiber yarn for technical textiles. For this purpose, two kinds of yarns are prepared, mechanical properties of coated and uncoated polyketone yarns such as tensile strength, elongation and modulus were examined before and after weather resistance test(temperature $60^{\circ}C$, humidity 60%, amount of power $0.67w/m^2$). The differences of mechanical properties between uncoated and coated yarns for high functional technical textiles and composite materials are estimated through this study.

• 대한유전성대사질환학회지
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• 제2권1호
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• pp.50-55
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• 2002

• 한국식품위생안전성학회지
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• 제25권2호
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• pp.129-132
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• 2010

The epidemiology of reported food-borne disease (FBD) outbreaks from 2001 to 2008 in Korea nd Japan were compared in this study. The outbreak rate of FBD in Japan was significantly higher although the average umber of patient in each outbreak in Korea was much higher. In both countries, summer was the season when most FBD outbreaks occurred. The comparison study revealed that FBD outbreaks in spring were more frequent in Korea, and outbreaks in winter were more frequent in Japan. Almost half of FBD outbreaks were observed at restaurants in both countries while FBD outbreaks at schools and work-places in Korea were much higher than in Japan. The most frequent cause of bacterial FBDs in Korea was pathogenic Escherichia coli followed by Salmonella species. On the other hand, Campylobacter jejuni was the most frequent source of bacterial FBDs in Japan. Norovirus, which is elated to uncontrolled hand hygiene and involvement of ill food workers, was the main cause of viral FBDs in both countries. In conclusion, there are common epidemiological characteristics as well as several differences in FBD outbreaks of Korea and Japan. These are suggested to be originated from the characteristic of climate, food sources, and life styles in two countries. Establishment of stricter control and surveillance system for FBD outbreaks are required or prevention and reduction of FBD outbreaks in both countries.

• 한국수산과학회지
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• 제48권3호
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• pp.301-307
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• 2015

Phlorotannins and marine algal polyphenols, including dieckol, 6,6-bieckol, phloroglucinol, phlorofucofuroeckol-A, and eckol, were isolated from brown seaweeds. These compounds have beneficial bioactivities, and Ecklonia cava has become widely used for the extraction and isolation of phlorotannins. Eckol, in particular, has been to shown to have antioxidant, anti-inflammatory, anticoagulatory, and photoprotective properties. However, due to its low abundance in weaweed, the isolation and purification of eckol are difficult. Its limited availability renders the isolation and purification of eckol labor-intensive processes. Centrifugal partition chromatography (CPC) is an efficient technique for the isolation and purification of eckol. In this study, eckol was isolated from the ethyl acetate fraction of the 70% ethanol extract of E. cava using CPC with a two-phase solvent system of a n-hexane:EtOAc:methanol:water (2:8:3:7, v/v) solution. The purity and anti-inflammatory activity of the isolated eckol were verified by high-performance liquid chromatography and by assaying lipopolysaccharide-induced inflammatory responses in an immortalized murine BV2 microglial cell line, respectively. In conclusion, CPC is a useful technique for simple and efficient isolation of eckol from E. cava.

• 한국수산과학회지
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• 제47권6호
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• pp.770-775
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• 2014

The green microalga of the genus Nannochloropsis (class Eustigmatophyceae) is a leading candidate for biofuel production due to its ability to accumulate high oil content (28.7% of cellular ash-free dry weight). We investigated the anti-inflammatory and anticancer activities of sterol-rich fraction from nannochloropsis oculata n-hexane (NOH) extract after saponification of the microalga. Among the fractions with n-hexane, chloroform and ethyl acetate, the n-hexane fraction showed the highest anti-inflammatory activity in LPS-stimulated RAW 264.7 macrophage as well as anticancer activity against human leukemia HL-60 cells without the cytotoxity. And the sterol-rich fraction was obtained from the n-hexane fraction by open silica column under the gradient solvent condition with 100% hexane (1L), hexane : ethyl acetate (20 : 1, 10 : 1, 5 : 1, 1 : 1, v/v). Among the four fractions (NOH-1~4), especially NOH-1 contained the highest content of sterols. NOH1 showed the highest HL-60 (about 85%) and NO inhibitory activities at the concentration of $100{\mu}g/mL$. These results demonstrated that the sterol-rich fraction from N. oculata might be a useful candidate as anti-inflammatory and anticancer agents for anti-inflammatory and anticancer activity.

• Elastomers and Composites
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• 제33권5호
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• pp.345-354
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• 1998

폴리아미드 수지가 첨가된 PVC졸 실란트의 유변학적 물성에 대해 연구하였다. PVC졸은 디옥틸프탈레이트로 PVC를 가소화시켜 제조된 것이다. 아민가가 달라 점도가 다른 두 종류의 폴리아미드를 사용하였는데 PVC졸의 점도, 틱소트로피 및 비중에 미치는 폴리아미드 수지 종류와 함량의 영향을 고찰하였다. 폴리아미드가 첨가된 PVC졸 실란트의 점도는 폴리아미드의 종류에 관계없이 시간에 따라 증가되었으나 폴리아미드 함량의 영향에 관해서는 아민가가 낮은 폴리아미드 수지 A가 첨가된 PVC졸 실란트의 점도는 폴리아미드 A함량에 따라 증가되고, 반면 아민가가 높은 폴리아미드B가 첨가된 PVC졸 실란트의 점도는 폴리아미드 B함량에 따라 감소되었다. 폴리아미드가 첨가된 PVC졸 실란트의 틱소트로피는 폴리아미드의 종류에 관계없이 그 함량에 따라 다른 거동을 보였다. $45^{\circ}C$의 수조에서 숙성한 후의 폴리아미드가 첨가된 PVC졸 실란트의 점도거동과 충진제인 $CaCO_3$ 함량의 영향도 고찰하였다.

• Tuberculosis and Respiratory Diseases
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• 제41권6호
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• pp.658-662
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• 1994

저자등은 종격동에서 늑막삼출액과 함께 종물이 있는 소견을 보였던 환자에서 세포진검사 및 면역화학적 검사를 통하여 평활근육종으로 진단된 1예를 경험하였기에 문헌고찰과 함께 이를 보고하는 바이다.

• 한국기계가공학회지
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• 제16권5호
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• pp.99-104
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• 2017

Friction stir welding is a solid-state joining process and is useful for joining dissimilar metal sheets. In this study, the experimental conditions of the friction stir welding were determined by the two-way factorial design to evaluate the characteristics of the dissimilar friction stir welding of AZ31 and AZ61 magnesium alloys. The levels of rotation speed and welding speed, which are welding variables, were 1000, 2000, 3000 rpm and 100, 200, 300 mm/min, respectively. From the results, the greater the rotation speed and the lower the welding speed of the tool were, the greater the tensile strength of the welded part was. The contribution of the welding speed of the tool is larger than that of the rotation speed of the tool. In addition, the optimal conditions for tensile strength in the dissimilar friction stir joint were predicted to be the rotation speed of 3000 rpm and welding speed of 100 mm/min, and the tensile strength under the optimal conditions was estimated to be $214{\pm}6.57Mpa$ with 99% reliability.

• 대한임상독성학회지
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• 제3권2호
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• pp.86-92
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• 2005

Purpose: The main cause of death due to acute organophosphate (OP) poisoning is believed acute respiratory failure caused by cholinergic reactions. Recently, advances in respiratory and intensive care make it possible to maintain the respiratory function of patients with OP poisoning, but the mortality rates remain high. The present study clarified the hemodynamics of patients with acute lethal OP poisoning. The purpose of this study was to analyse the outcomes and predictors of mortality in patients with acute OP poisoning requiring intensive care. Methods: We reviewed medical and intensive care records of patients with acute OP poisoning admitted to emergency department and ICU between March 1998 and Aug 2005. We collected patient information regarding poisoning, clinical, and demographic features. Results: During the study period, 67 subjects treated with intensive care and ventilator management in addition to gastric decontamination standard therapy with atropine and 2-PAM. Of 67 patients, 13 died. Kaplan-Meier survival analysis demonstrated a steep decline in the cumulative survival to $86.6\%$ during the first week. Mean arterial pressure < 60 mmHg within the first 24 hours was recognized as a poor prognostic indicators among mechanical ventilated patients. Conclusion: Most OP poisoning-related deaths occurred within the first week of poisoning. Mean arterial pressure lower than 60 mmHg might be the best predictor of poor outcome. We speculated that the refractory hypotension is the leading cause of death in patients with lethal OP poisoning that receiving mechanical ventilation and maximal supportive care.

• 문화기술의 융합
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• 제1권1호
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• pp.73-77
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• 2015

기존의 스포츠 시뮬레이터 제품들은 모션 플랫폼의 운동과 간단한 시각적 콘텐츠를 이용한 실감 표현에 집중되어 있고 놀이위주의 적용에 국한되어 있어, 사용자가 체감할 수 있는 오감 자극효과가 낮아 고실감 적용에는 부족하며, 전문 콘텐츠 부재로 인해 교육용 스포츠 시뮬레이터로서의 적용은 아직 어렵다. 본 연구에서는 다종목 교환이 가능한 다축 공통 플랫폼과 교환식 스포츠 모듈로 분리하여 공통 플랫폼의 운동 자유도를 4자유도(Surge, Sway, Heave, Yaw) 운동을 할 수 있도록 스포츠 플랫폼을 설계하였다. 이 플랫폼은 안정성을 보장하고 간섭을 최소화하는 데 목적이 있다. 이 플랫폼에 탑재되는 교환식 스포츠 모듈의 운동 자유도는 2자유도(Roll, Pitch)로 승마, 요트와 같은 다양한 운동이 적용이 가능하고, 독립적인 회전 2자유도의 체감형 시뮬레이터의 구현이 가능하도록 하였다.