• 대한기계학회논문집A
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• 제34권12호
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• pp.1837-1842
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• 2010

화석에너지의 고갈로 인한 대체 에너지 연구는 최근 수십 년 동안 계속 행해지고 있다. 원자력 에너지와 비교해서 낮은 전기발생 효율에도 불구하고, 환경친화적이며 태양이라는 영구성으로 태양에너지는 주목 받고 있다. 본 논문에서는 태양전지의 효율에 가장 영향을 미치는 인자로 햇빛 입사각의 변화와 Top Connector 형상이라 가정하고 MATLAB 과 MathCAD 를 이용하여 모사하였다. 실험모사 결과 상용화 제품인 500um 선폭, 5um 높이 Top Connector 형상과 비교하여, 최고 10%의 태양전지 효율증가는 Top Connector 후막 두께가 25~50 um, 선폭 두께가 50~100um 영역에서 찾을 수 있었다. 10 만 cps 의 점도를 갖는 은페이스를 500um 의 MDDW (Micro-Dispensing Deposition Writing) 직접분사 노즐을 이용하여 성공적으로 25 um 후막을 형성하였다.

• 동의생리병리학회지
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• 제29권4호
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• pp.322-329
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• 2015

Cirsium japonicum var. ussuriense are often used in treatment of human diseases such as hemorrhage, blood congestion and inflammation in Korea. However, there was not report on the anti-obesity efficacy of water extracts from different organs of C. japonicum var. ussuriense. Here, we investigated the antioxidant effects of water extracts of flowers, leaves and roots from C. japonicum var. ussuriense. Total polyphenol amounts of the flower extract showed higher than those of leaf and root extract. Flower extract also showed the high antioxidant activities such as DPPH radical scavenging activity and reducing power. We also investigated the anti-obesity effects of water extracts of flowers, leaves and roots from C. japonicum var. ussuriense in 3T3-L1 cells and high fat diet-induced obesity mice. The mice were divided into four groups [high fat diet (HFD) control, HFD + leaf extract, HFD + flower extract and root extract] and administered with each extract (200 mg/kg) for 12 weeks. The flower and leaf extract significantly suppressed the levels of oil red O and triglyceride content. The flower and leaf extract also significantly reduced the triglyceride, total cholesterol and lower density lipoprotein levels of plasma as well as body and abdominal fat weight. Furthermore, oral glucose tolerance in the flower and leaf extract groups were significantly ameliorated in comparison to the high fat diet group. Therefore, these results indicate that the flower and leaf extract could ameliorate obesity and attenuate blood glucose level in high fat diet-induced obesity mice. We conclude that this study may provide positive insights into water extracts of flowers and leaves from C. japonicum var. ussuriense as a functional food ingredient for treatment of obesity.

• 대한예방한의학회지
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• 제16권1호
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• pp.1-13
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• 2012

The objective of this study is to discuss the role of integrative medicine (IM) in contemporary health care settings, and how and which factors affect and facilitate the success of IM in terms of the integration of complementary and alternative medicine (CAM) and conventional medicine in primary health care (PHC). IM is meant to provide the best possible health care, for both patient and physician. The way of IM use in the developed countries presents various ways that IM can be provided, and it appears that strategies have been successfully developed to facilitate integration. Although few of the barriers to the integration of CAM and conventional medicine have been resolved, concerns over the legitimacy of CAM in health care (e.g., safety, biomedical evidence, and efficacy) are being overcome by the use of evidence-based practice in IM delivery. There are dominant models of IM that have been developed. The model types signify different levels of equity between CAM and conventional medicine in regard to the power, autonomy, and control held by each. However, the factors common to all IM models, whether describing CAM as supplementary or complementary to conventional medicine, is the concept of a health care model that aspires to be client-centred and holistic, with focus on health rather than disease as well as mutual respect among peer practitioners. Finally, this study concluded that the growth and viability of traditional Korean medicine(TKM) depend on evidence-based practices and identifying the successful influences on the integration of TKM and conventional medicine for recognition of its inherent value in PHC. Some recommendations for the integration of TKM and conventional medicine were suggested.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.544-545
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• 2013

Recently, low-temperature atmospheric-pressure plasmas have been investigated [1,2] for biomedical applications and surface treatments. Experiments for improving hydrophilicity of stainless steel (SUS 304) plate with atmospheric microwave argon and H2O2 mixture plasma jet [3] were carried out and experimental measurements and plasma simulations were conducted for investigating the characteristics of plasma for the process. After 30 s of low power (under 10 W) and low temperature (under $50^{\circ}C$) plasma treatment, the water contact angle decreased rapidly to around $10^{\circ}$ from $75^{\circ}$ and was maintained under $30^{\circ}$ for a day (24 hours). The surface free energy, calculated from the contact angles, increased. The chemical properties of the surface were examined by X-ray Photoelectron Spectroscopy (XPS) and the surface morphology and roughness were examined by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) respectively. The characteristics of plasma sources with several frequencies were investigated by Optical Emission Spectroscopy (OES) measurement and one-dimensional Particle-in-Cell (PIC) simulation and zero-dimensional global simulation [4]. The relation between plasma components and the efficacy of the surface modification were discussed.

• Advances in materials Research
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• 제5권4호
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• pp.279-298
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• 2016

Present disquisition proposes an analytical solution method for exploring the buckling characteristics of porous magneto-electro-elastic functionally graded (MEE-FG) plates with various boundary conditions for the first time. Magneto electro mechanical properties of FGM plate are supposed to change through the thickness direction of plate. The rule of power-law is modified to consider influence of porosity according to two types of distribution namely even and uneven. Pores possibly occur inside FGMs due the result of technical problems that lead to creation of micro-voids in these materials. The variation of pores along the thickness direction influences the mechanical and physical properties. Four-variable tangential-exponential refined theory is employed to derive the governing equations and boundary conditions of porous FGM plate under magneto-electrical field via Hamilton's principle. An analytical solution procedure is exploited to achieve the non-dimensional buckling load of porous FG plate exposed to magneto-electrical field with various boundary condition. A parametric study is led to assess the efficacy of material graduation exponent, coefficient of porosity, porosity distribution, magnetic potential, electric voltage, boundary conditions, aspect ratio and side-to-thickness ratio on the non-dimensional buckling load of the plate made of magneto electro elastic FG materials with porosities. It is concluded that these parameters play remarkable roles on the dynamic behavior of porous MEE-FG plates. The results for simpler states are confirmed with known data in the literature. Presented numerical results can serve as benchmarks for future analyses of MEE-FG plates with porosity phases.

• 대한화장품학회지
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• 제33권4호
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• pp.209-217
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• 2007

멜라닌은 UV로부터 피부를 보호하는 기능을 하며, 인종과 피부색을 결정하는 요인이다. 또한 미백 기능성 화장품개발의 주요 목표물이기도 하다. 최근 미와 관련된 화장품 시장이 급성장 하면서 미백효능 증대를 위한 연구들이 활발히 진행되고 있고, 보다 안전하고 효능을 극대화하기 위한 미백 기성화장품의 개발은 관심업계의 주력 분야이다. 또한 경쟁력을 확보하기 위한 수단으로 지속적인 특허 출원이 따르고 있다. 특허는 관련업계의 연구경향을 파악할 수 있는 중요한 문헌이기도 하다. 본 논문에서는 미백 기능성화장품과 관련된 특허 분석을 통하여 관련 업계의 미백연구기술의 개발 동향을 소개하고 미백 기능성 화장품의 개발 및 활성성분의 원료개발에 대한 이해를 돕고자 한다.

• 응용통계연구
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• 제22권6호
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• pp.1249-1263
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• 2009

표본수 결정에서 요구되는 검정력 함수는 연구가설에 상응하는 가장 적절한 검정방법에 의한 것이어야 한다. 의학연구의 논문에 자주 나타나는 순위자료 또는 범주형 빈도자료의 분석에는 비모수적 방법이 적절하며, 본 논문에서는 단변량 및 이변량 순위변수에 대한 윌콕슨-만-휘트니(Wilcoxon-Mann-Whitney; WMW) 검정법에 의한 표본수 결정방법을 제시한다. 단변량 순위변수의 윌콕슨 검정에서는 귀무가설과 대립가설 하의 분산을 이용한 표본수 공식이 귀무가설 하의 분산만 이용한 표본수 공식보다 정확하지만, 대립가설 하의 분산식에 나타나는 확률값이 일반적으로 알려져 있지 않으므로 이 확률값의 추정이 문제가 된다. 모의실험으로 두 방법에 대한 장, 단점을 알아본다. 효능과 안전성의 이변량 순위변수에서는 이변량 WMW 검정법에 의한 표본수 결정방법이 모수적 검정법에 의한 표본수 결정방법보다 더욱 바람직하다.

• 한국전자통신학회논문지
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• 제6권6호
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• pp.855-864
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• 2011

본 논문은 IPMSM(Interior Permanent Magnet Synchronous Motor)의 고성능 운전을 위해 비선형 제어를 기반으로 하는 적응 백스텝핑 제어기를 제안한다. 먼저 각속도의 추종성능을 향상시키기 위해서 비선형 백스텝핑 제어기를 설계한다. 파라메타 변동의 영향을 고려하지 않고 설계된 제어기는 고성능 운전이 어렵다. 부하토크의 변동에 대해 실시간 적응할 수 있는 파라메타 추정기를 설계에 포함하여 고성능 운전이 가능하게 한다. 또한 전동기의 효율적인 전력소비를 위하여 최대토크를 얻기 위한 최소전류의 운전을 할 수 있도록 제어기를 설계하였다. 제안된 제어기로 2마력급의 IPMSM에 적용하여 각속도 레퍼런스에 대한 추종성능과 부하토크 변동에 대한 추정, 그리고 MTPA(Maximum Torque per Ampere) 운전을 시험하여 일정토크 운전영역에서 안정화된 강건한 제어기임을 시뮬레이션을 통해 확인할 수 있었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권3호
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• pp.950-975
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• 2016

Device-to-Device (D2D) communication underlaying cellular networks is a promising add-on component for future radio communication systems. It provides more access opportunities for local device pairs and enhances system throughput (ST), especially when mobile relays (MR) are further enabled to facilitate D2D links when the channel condition of their desired links is unfavorable. However, mutual interference is inevitable due to spectral reuse, and moreover, selecting a suitable transmission mode to benefit the correlated resource allocation (RA) is another difficult problem. We aim to optimize ST of the hybrid system via joint consideration of mode selection (MS) and RA, which includes admission control (AC), power control (PC), channel assignment (CA) and relay selection (RS). However, the original problem is generally NP-hard; therefore, we decompose it into two parts where a hierarchical structure exists: (i) PC is mode-dependent, but its optimality can be perfectly addressed for any given mode with additional AC design to achieve individual quality-of-service requirements. (ii) Based on that optimality, the joint design of MS, CA and RS can be viewed from the graph perspective and transferred into the maximum weighted independent set problem, which is then approximated by our greedy algorithm in polynomial-time. Thanks to the numerical results, we elucidate the efficacy of our mechanism and observe a resulting gain in MR-aided D2D communication.

• 동의생리병리학회지
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• 제31권3호
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• pp.188-193
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• 2017

This study investigated the antioxidant activities of distilled water, ethanol and methanol extracts of Plunus mume flower buds (PFB). The various solvent extracts of PFB were evaluated for their total polyphenol, flavonoid, reducing power and free radical scavenging activities by FRAP and DPPH analysis. The ethanol extract of PFB contained significantly higher amounts of total polyphenols (145 mg GAE/g) and flavonoids (25.43 mg QE/g) than methanol (132 and 25.42) and distilled water (113.6 and 18.04). Among solvent extracts of PFB, the ethanol extract showed the highest antioxidant activities. The 100% ethanol extract of PFB contained significantly higher amounts of total polyphenols and flavonoids than 70% and 50% ethanol extracts. Moreover, the 100% ethanol extract of PFB showed high efficacy in DPPH radical scavenging activity and in collagenase inhibition activity. This results suggest that 100% ethanol extract of PFB has the most effective antioxidant capacity compared to the methanol and water extracts tested in the present study. Thus, it can be applied for the effective extraction of functional material from PFB for usage of cosmeceutical and/or food industries.