• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1675-1679
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• 2011

To improve the quality and palatability of Kochujang, the physicochemical properties, antioxidant capacity, and sensory evaluation of Kochujang were assessed when red ginseng and wild herbal extract were added during fermentation. This study investigated the antioxidant capacities of general Kochujang (GK) and Kochujang prepared with red ginseng and fermented wild herbal extract (RGK) by employing various in vitro antioxidant assays such as DPPH and FRAP assays. Inhibition of lioxygenase (LOX) activity was also investigated. RGK exhibited significant antioxidant effects compared to control in DPPH, FRAP, and LOX assays. The LOX inhibitory activity of RGK ($68.68{\pm}3.37%$) at 100 ${\mu}g$/mL was markedly higher than those of GK ($31.21{\pm}2.64%$) and NDGA (positive control, $30.54{\pm}1.36%$). All concentrations of RGK showed significantly higher FRAP activities than that of GK. The addition of red ginseng and fermented wild herbal extract exhibited better sensory characteristics in terms of color, flavor, taste and overall preference. We concluded that RGK improves not only functional properties but also sensory properties as well.

• The Korea Journal of Herbology
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• v.37 no.5
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• pp.27-35
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• 2022

Objectives : 3-Acetyl-11-keto-𝛽-boswellic acid (AKBA) is a major active compound in Boswellia serrata. We investigated the arthritic changes following AKBA administration in monosodium iodoacetate (MIA)-induced osteoarthritis rats. Methods : All rats were randomly divided into five groups: Normal, Control, INDO (indomethacin 2 mg/kg treated), AKBA30 (AKBA 30 mg/kg treated), and AKBA60 (AKBA 60 mg/kg treated); drugs were given 2 weeks before MIA injection. For all groups except the normal group, 50 µL of sterile saline with MIA (80 mg/mL) was injected into the right knee joint 2 weeks after drug administration. The drug administration was continued for 4 weeks from 1 week after osteoarthritis induction. The histomorphological changes of knee joint cartilage were observed by H&E staining. Also, the levels of glycosaminoglycan (GAG), cartilage oligomeric matrix protein (COMP), 5-lipoxygenase (5-LOX), 5-LOX-activating protein (FLAP), and leukotriene B₄ (LTB₄) in the knee joint were determined by the ELISA kits. The expressions of mitogen-activated protein kinases (MAPKs), inflammatory cytokines, and matrix metalloproteinases (MMPs) in knee joint were detected by Western blot. Results : Data show that levels of 5-LOX, FLAP, LTB4, and COMP were downregulated significantly in the AKBA treated groups when compared to those in the Control group. On the other hand, GAG levels were significantly elevated. As a result of Western blot, the AKBA-treated groups significantly inhibited phosphorylation of MAPKs. In addition, significant downregulation of the expression of inflammatory cytokines and MMPs was found in the AKBA-treated groups. Conclusion : Our findings suggest that administration of AKBA could exert better chondroprotective and anti-inflammatory effects for MIA-induced osteoarthritis rats.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2002.04a
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• pp.77-77
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• 2002

초소형 공중발사체 설계 시 하이브리드 모터의 적용가능성에 대한 연구를 실시하였다. HTPB/LOX를 추진제로 하여 마차바퀴형 연료 그레인, 산화제 탱크 가압방식을 사용하였고, 성능특성을 계산하기 위하여 하이브리드 연료의 연소율이 일정하다고 가정 하였다. 본 연구에 사용된 임무는 중량 3.5kg의 나노위성을 근지점 고도 200km, 원지점 고도 1,500km의 타원궤도로 진입시키는 것을 목적으로 하는 로켓의 1단 부분에 관한 것으로 1단의 발사속도는 M=1.3, 발사고도는 12km, 연소종료 고도는 40km이다. 1단에 대한 페이로드 중량은 127.5kg이고, 속도증가분($\Delta$V)은 3,330m/s이다. 모선은 F-4E를 사용하였고 모선의 특성상 발사체의 총 중량이 1,000kg이하로 제한되고 길이와 직경이 5m${\times}$5m로 제한되나 1단에 대한 길이의 제한조건은 현재까지 명확히 정립되지 않은 상태이다. 설계과정에서의 변수는 연료 그레인 포트 개수, 초기 산화제 플럭스, 연소실 압력을 사용했고, 설계 제한조건은 추진제 중량, 평균 비추력, 평균 추력, 연소시간, 1단 길이, 직경, 연소시간이고, 이들의 범위는 모선의 특성과 초소형 공중발사체의 임무특성에 맞게 설정하였다.

• Aerospace Engineering and Technology
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• v.6 no.1
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• pp.128-135
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• 2007

Combustion characteristics of full-scale gas generators were studied experimentally by changing the injector number installed at the injector head. Three full-scale gas generators were utilized; they have same total mass flow rate but mass flow rates per injector are different. Thirteen, nineteen and thirty seven injectors, which have internal-mixing and double-swirl characteristics, are distributed in injector heads, respectively. The results showed that pressure fluctuations in the gas generators with 13 and 19 injectors didn't occur around longitudinal resonant frequency, however longitudinal-mode pressure fluctuation appeared slightly in the gas generator with 37 injectors. As the number of injectors increased, deviations of temperature distribution in the combustion chamber decreased gradually, but the damage of injector LOx posts became a little severe.

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.1
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• pp.56-64
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• 2010

A system design has been conducted of the liquid rocket engine for Korean launch vehicle (KSLV-II, Korea Space Launch Vehicle II). The present turbopump-fed liquid rocket engine of vacuum thrust 76 ton and vacuum specific impulse 297 sec adopts gas generator cycle. The combustion pressure of the regeneratively cooled combustor is 60 bar. The propellant is LOx/kerosene. The engine is started by pyrostarter and the combustor is ignited by TEA (TriEthylAluminium). The engine system performance and the subsystems performance requirements are given through energy balance analysis. The combustion pressure, specific impulse and the engine mass are analyzed to be reasonable comparing with the published data. The startup analysis method which will be used in the future has been validated against the turbopump-gas generator coupled test. The tuning method for performance variation of the engine which is not actively controled has been prepared by mode analysis and performance deviation analysis.

• Archives of Pharmacal Research
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• v.29 no.8
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• pp.617-623
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• 2006

In our ongoing search for bioactive compounds originating from the endemic species in Korea, we found that the hexane and EtOAc fractions of the MeOH extract from the root of Dystaenia takeshimana (Nakai) Kitagawa (Umbelliferae) showed cyclooxygenase-2 (COX-2) and 5- lipoxygenase (5-LOX) dual inhibitory activity by assessing their effects on the production of prostaglandin $D_2\;(PGD_2)$ and leukotriene $C_4\;(LTC_4)$ in mouse bone marrow-derived mast cells. By activity-guided fractionation, five coumarins, viz. psoralen (2), xanthotoxin (3), scopoletin (4), umbelliferone (5), and (+)-marmesin (6), together with ${\beta}-sitosterol$ (1), were isolated from the hexane fraction, and two phenethyl alcohol derivatives, viz. 2-methoxy-2-(4'-hydroxyphenyl)ethanol (7) and 2-hydroxy-2-(4'-hydroxyphenyl)ethanol (8), three flavonoids, viz. apigenin (9), luteolin (10), and cynaroside (11), as well as daucosterol (12) were isolated from the EtOAc fraction using silica gel column chromatography. In addition, D-mannitol (13) was isolated from the BuOH fraction by recrystallization. Two of the coumarins, scopoletin (4) and (+)- marmesin (6), the two phenethyl alcohol derivatives (7, 8) and the three flavonoids (9-11) were isolated for the first time from this plant. Among the compounds isolated from this plant, the five coumarins as well as the three flavonoids showed COX-2/5-LOX dual inhibitory activity. These results suggest that the anti-inflammatory activity of D. takeshimana might in part occur via the inhibition of the generation of eicosanoids.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.3
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• pp.119-126
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• 2019

For rockets using cryogenic liquid hydrogen or liquid oxygen, chilling is required to avoid cavitation and surge problems. Chilling is categorized by the initial chilling/filling stage and the low-temperature maintenance stage. In addition, to improve satellite insertion capability, a multi-ignition capability is required and accordingly chilling to prepare for the next ignition during low-gravity coasting is also required. This paper describes the overall aspects of filling and low temperature maintain marinating for the booster and the upper stage engine including chilling for multi-ignition.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2000.04a
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• pp.12-12
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• 2000

우리 나라는 일본상공의 비행을 피하기 위하여 제주도와 남해안 근해로 발사장 선정이 국한되는 지정학적인 위치로 볼 때 발사장 선택에 제한이 없는 공중발사에 대한 가능성 연구가 필요한 시점에 있다. 본 연구는 우리 나라와 같은 분단 된 특수상황 그리고 지정학적 위치에서의 발사장을 고려한 우주 발사체 개발의 필요성에 따라 F-4에 장착 가능한 3단형 공중발사 로켓을 설계하고 1/3의 축소 모형을 제작하였다. 2kg의 payload를 갖는 발사체의 1단은 LRM ( Lox/kerosene )을 사용하였고 2, 3단은 SRM ( HTPB/AP/Al )을 사용하였으며 발사고도는 11-l2km 상공에서 F-4에 의해서 발사되고 31km지점에서 1단 분리가 이루어지며 62km지점에서 2단 분리와 nose fairing을 분리하게 된다. 전장은 6.85m 이며 전체 무게는 560.6kg 이고 전체 발사체 시스템의 CAD 도면은 아래 그림 1과 같이 주어져 있다. 그림 2에서는 F-4E phantom의 장착성을 검토해 본 결과 장착이 가능함을 알 수 있었으며 추진제 양의 감소로 크기를 대폭 줄일 수 있었다.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.1 s.24
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• pp.117-124
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• 2006

Experiments on film cooling were performed with a small scale rocket engine homing liquid oxygen (LOx) and Jet A-1(jet engine fuel). Film coolants(Jet A-1 and water) were injected through the film cooling injector. Film cooled length and the outside wall temperature of the combustor were determined for chamber pressure, and the different geometries(injection angle) with the flow rates of film coolant. The loss of characteristic velocity due to film cooling was determined for the case of film cooling with water and Jet A-1. As the coolant flow increases, the outside wall temperatures decrease but the decrease in the outside wall temperatures reduced over the 8 percent film coolant flow rate. The efficiency of characteristic velocity was decreased with the Increase of the film coolant flow rate.

• Korean Journal of Pharmacognosy
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• v.32 no.3 s.126
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• pp.189-192
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• 2001

Scillascilloside E-3 (1) and E-1 (2) were isolated from the bulbs of Scilla scilloides. The cytotoxic activities of these compounds were tested against murine (B16/F-10, 3LL) and human cancer cell lines (MCF7, PC-3, HT29, LOX-IMVI, A549 and HT1080). These compounds exhibited a significant cytotoxic activities against all tested cancer cells. Futhermore, the contents of 1 and 2 in S. scilloides are 43.2 and 27.9 mg/kg, respectively.