• 한국항공운항학회지
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• 제26권3호
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• pp.48-54
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• 2018

This paper deals with a development of a quad-rotor for a hovering attitude control. First, a rotational dynamics are derived to design an attitude controller. The attitude controller is based on PI (Proportional-Integral) controller. For a stable attitude control, an anti-windup method applies to the PI attitude controller. Additionally, a complementary filter is used to obtain more reliable attitude. Gain values of the attitude controllers based on the anti-windup method are obtained through tests. Finally, the quad-rotor with the anti-windup based PI attitude controller is developed and a hovering attitude control flight tests are performed. As a result, the developed quad-rotor is capable of stable hovering.

• Journal of Positioning, Navigation, and Timing
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• 제9권2호
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• pp.51-57
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• 2020

For the purpose of development of anti-jamming GPS receiver we have developed an anti-jamming algorithm and its Simulink implementation model. The algorithm used here is a form of Space-Time Adaptive Processing (STAP) filter which is well known as an effective way to remove wideband jamming signals. We have chosen Minimum Variance Distortionless Response (MVDR) block-adaptive beamforming algorithm for our development since it can provide relatively fast convergence speed to reach optimal weights, stable and high suppression capability on various types of jamming signals. We will show modeling results for this MVDR type adaptive beamformer and some simulation results. We also show the integrity of the demodulated satellite signals and the accuracy of resulting navigation solutions after anti-jamming operation.

• Journal of Applied Biological Chemistry
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• 제61권1호
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• pp.39-46
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• 2018

Column chromatographic separation of the MeOH extract from the roots of Dicentra spectabilis yielded fourteen compounds, menisdaurin (1), menisdaurilide (2), trans-N-p-coumaroyltyramine (3), trans-N-p-feruloyltyramine (4), 4-O-feruloylquinicacid (5), chlorogenic acid (6), 3-O-feruloylquinicacid (7), ferulic acid (8), protopine (9), Kaempferol 3,7-di-O-${\beta}-{\text\tiny{D}}$-glucopyranoside (10), kaempferol 3-O-${\beta}-{\text\tiny{D}}$-glucopyranosyl-7-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranoside (11), ${\alpha}-rhamnoisorobin$ (12), astragalin (13), and nicotiflorin (14). Their structures were determined on the basis of NMR spectroscopic data. Among them, compound 1, 3-8, and 10-14 isolated from this plant were reported for the first time. The isolated compounds (1-14) were tested for nitric oxide (NO) inhibitory activity on lipopolysaccharide-stimulated RAW 264.7 cells. Compound 3, 4 and 12 significantly inhibited NO production. Moreover, Compound 3 suppressed pro-inflammatory cytokines ($TNF-{\alpha}$, $IL-1{\beta}$ and IL-6) in a dose- dependent manner. These data suggest that compound 3 possess anti-inflammatory activity and might be useful natural materials for development of anti-inflammatory agent.

• 한국식품영양학회지
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• 제27권6호
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• pp.1090-1095
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• 2014

Anthocyanins, a class of flavonoids, are natural water-soluble pigments, which are mainly found in vegetables and fruits. Anthocyanins have attractive pharmacological activities, such as anti-oxidant, anti-inflammatory, anti-cancer, and anti-diabetic. The purpose of this study was to investigate the protective effects of anthocyanins-rich fraction (ANF) from Korean purple sweet potato variety, "Shinjami", against hydrogen peroxide ($H_2O_2$)-induced oxidative stress. In our results, pre-treatment of HepG2 cells with ANF ($10{\mu}g/mL$) significantly prevented cell death and maintained cell integrity, following exposure to 0.9 mM hydrogen peroxide. The $H_2O_2$-dependent production of intracellular ROS was also significantly decreased by pre-treatment with ANF (6 h, $10{\mu}g/mL$). In addition, ANF increased the mRNA levels of antioxidant enzymes, catalase and glutathione level in $H_2O_2$-treated HepG2 cells. These results indicated that ANF protected HepG2 cells against $H_2O_2$-induced oxidative stress by inducing protective system.

• 농업과학연구
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• 제46권3호
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• pp.653-660
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• 2019

Ganoderma lucidum, an oriental polypore fungus and medicinal mushroom, has a long history of use for promoting health and longevity in Korea, China, and other Asian countries. This study was aimed at determining the anti-inflammatory activity and mechanism of action of Ganoderma lucidum in murine macrophage RAW 264.7 cells. Ganoderma lucidum was extracted with ethanol and freeze-dried. The anti-inflammatory effect (nitrite production) of Ganoderma lucidum extracts was tested using a nitric oxide (NO) colorimetric assay. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) was performed to quantify the mRNA expression of cytokines including tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$), interleukin $(IL)-1{\beta}$, and IL-6. Western blotting was performed to measure the expression levels of inflammation-related proteins, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor kappa B ($NF-{\kappa}B$) p65, and phosphorylated $NF-{\kappa}B$ p65. The NO colorimetric assay showed that NO production increased with the treatment of lipopolysaccharide in (LPS)-activated RAW 264.7 macrophages and decreased with the cotreatment of Ganoderma lucidum extracts and LPS. Ganoderma lucidum extracts repressed the mRNA expressions of cytokines, which were increased after the LPS treatment. In addition, Ganoderma lucidum extracts inhibited the LPS-induced expression of iNOS and COX-2 and the LPS-induced phosphorylation of $NF-{\kappa}B$ p65. These results suggest that the Ganoderma lucidum extracts exert an anti-inflammatory activity by inhibiting $NF-{\kappa}B$ related proteins and cytokines.

• 한국초지조사료학회지
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• 제43권3호
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• pp.138-147
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• 2023

Buckwheat (Fagopyrum esculentum), which is a traditional Korean crop, has been known as a health food due to its rich nutrition. This study was conducted to evaluate the change in flavonoid content of flowers and seeds during post-flowering growth of Korean tartary buckwheat variety 'Hwanggeummiso', with the aim of providing basic data for the development of functional food and feed additive. Tartary buckwheat took 69 and 99 days from the sowing date to reach the flowering and maturity stages, respectively. As a result of examining the flavonoid components of each part of tartary buckwheat, chlorogenic acid, rutin, and isoquercitrin of flowers increased from the flowering period on 22 May (0 days after flowering) to 42 days after flowering, while quercetin increased until 21 days after flowering and then decreased thereafter. In seeds, chlorogenic acid, rutin, and isoquercitrin were most abundant at the time of seed-bearing on 14 days after flowering, and showed a decreasing tendency thereafter. On the other hand, quercetin showed a tendency to increase until 21 days after flowering and then decrease. Overall, the flavonoid content was higher in flowers than in seeds, with rutin being particularly prominent. Based on this, the possibility as food materials and feed additives was confirmed using buckwheat produced in Korea.

• 한국보건간호학회지
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• 제34권2호
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• pp.289-300
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• 2020

Purpose: This study aimed to identify gender differences associated with weight related teasing by parents, and development of anti-fat attitudes among Korean children aged 5 to 7 years. Methods: This study used a descriptive cross-sectional design. Questionnaire interviews were conducted by enrolling 222 healthy children having normal development and living with their parents in South Korea. Results: Results showed gender and parental weight-related teasing was significantly associated with anti-fat attitudes among children. Significance of the association between parental weight-related teasing and anti-fat attitudes among kindergarten children differed according to the child's gender. Among girls, the higher level of parental weight-related teasing was associated with greater anti-fat attitude. However, parental weight-related teasing was not associated with increased anti-fat attitude among boys. Conclusion: Considering our study results, we recommend developing programs aimed towards decreasing teasing in the family environment, such as changing the gender-specific weight norms to prevent anti-fat attitudes in Korean girls.

• 한국입자에어로졸학회지
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• 제12권4호
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• pp.151-159
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• 2016

Since airborne viruses have been known to aggravate indoor air quality, studies on development of anti-viral air filter increase recently. In this study, a mass aerosol particle generator for coating a commercial air filter (over $300{\times}300mm^2$) was built, and evaluated by comparing a commercial particle generator. Then, via this device, a commercial air filter was coated with anti-viral material ($SiO_2-Ag$ nanoparticles in this study), so fabrication of commercial anti-viral air filter was performed and the pressure drop, filtration efficiency, and anti-viral ability of the filter were evaluated against aerosolized bacteriophage MS2 in a continuous air flow condition. The result showed that the particle generation of the new generator was more than about 8.5 times over which of the commercial one. Consequently, $SiO_2-Ag$ particle coating on a filter does not have significant effects on the filtration efficiency and pressure drop with different areas, and the average anti-viral efficiency of the $SiO_2-Ag$ filter was about 92% when the coating areal density was $1.0{\times}10^{12}particles/m^2$.

• 한국해양바이오학회지
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• 제5권4호
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• pp.8-14
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• 2011

Although marine living organism contains a numerious number of compounds, it is difficult to collect these compounds in a large scale for medicinal application. However, in recent years, several bioactive compounds isolated from marine macroalgae have been proved to be able to provide potential sources for development of medicinal products because they can be obtained in large amount from marine. A number of studies have reported a variety of effects of marine macroalgae but a few anti-inflammatory activity of marine macroalgae have recently been published. Herein, we reviewed novel anti-inflammatory compounds recently isolated from marine brown algae, green algae and red algae. From this survey, in particular, some compounds contained in edible macroalgae exert anti-inflammatory effects with inhibition on cyclooxygenase-2 (COX-2), inducible nitric oxide synthase(iNOS) and matrix metalloproteinases (MMPs) activity regulated by nuclear factor-kappa B transcription factor that play a key role in cancer as well as inflammation, demonstrating to be able to potentially apply to development of anti-inflammatory agent for chemoprevention of cancer. Furthermore, some macroalgae and their compounds with both excellent anti-inflammatory activity and very low toxicity can select a potential candidates capable of preventing or treating several chronic inflammation such as colitis, hepatitis and gastritis, leading to cancer.

• 대한화장품학회지
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• 제31권2호
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• pp.147-152
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• 2005

본 연구는 화장품 소재개발에 있어 보다 안전하고 우수한 활성을 나타내는 천연 소재를 개발하고자 하였다 본초학과 식품공전에 수재되어 있는 전통생약재에 대한 연구는 국내 화장품 원료개발의 중요한 부분으로써 우리나라가 경쟁력을 가질 수 있는 부분으로 사료되며, 본 연구에서는 폐와 피부 질환에 사용되는 전통생약재 121종을 선별하였다. 이들 전통생약재 추출물들을 대상으로 DPPH free radical 소거법과 SOD 활성 측정법에 의한 항산화 활성과 주름 생성의 주 기전에 관련된 elastase 효소 억제 활성을 관찰하였다. 항산화 활성을 보이면서도 주름 형성관련 효소인 엘라스타제에 대한 억제 활성을 지니는 전통생약재 9종을 선별하였다. 항주름/피부탄력 활성을 나타내리라 사료되는 9종의 생약재에 대한 각각의 정상 세포에 대한 세포독성을 측정한 결과, 효과를 나타내리라 여겨지는 0.1 g/mL 이하의 농도에서 세포 독성이 없는 것으로 확인되었다. 또한 인체피부 일차 자극 실험을 통해 피부자극 유무를 측정한 결과 피부자극이 없음을 확인하였다 본 연구를 통해 식품공전과 동의보감 자료에 의거, 폐와 피부질환에 관련된 전통생약재 121종 중 9종에 대해 항주름과 피부탄력에 관련한 향장 소재로써의 개발 가능성을 확인하였다.