• Bulletin of the Korean Space Science Society
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• 2003.10a
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• pp.50-50
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• 2003

본 연구에서는 행성 근접통과(Gravity Assist, Swingby, Flyby)를 이용한 행성간 탐사선의 궤도를 설계할 수 있는 알고리즘 개발을 자체적으로 수행하였다. 미 항공우주국(NASA)에서는 이를 이용한 행성간 탐사선의 궤도에 관한 연구를 이미 1950년대부터 시작하여 왔으며, 1973년 Mariner 10호가 한번에 두 행성, 금성과 수성을 탐사하는데 성공하였다. 행성간 임무에 있어서 행성 근접통과를 적절하게 이용한다면 임무 수행시 요구되는 에너지를 최소화 시킬 수 있어 발사비용의 절감효과와 함께 한번의 발사로 여러 행성의 탐사가 가능하여 임무의 효율성을 증대 시킬 수 있다. 행성 근접통과를 이용한 행성 탐사선의 궤도설계를 위해서는 근접 통과하는 행성(Flyby planet)에서의 진입속도벡터( $V_{\infty}$$^{ -}$) 및 출발속도벡터( $V_{\infty}$$^{+}$)의 크기, 근접 통과시의 비행 고도(Flyby altitude), 근접 통과 행성과의 충돌여부 분석(B-plane analysis), 최종적으로 도착하고자 하는 행성(Target planet)의 위치 등 많은 제한조건이 고려되어야 한다. 연구된 알고리즘의 결과를 미 항공우주국 (NASA)의 임무였던 Mariner 10호의 결과와 비교하여 보았으며, 우리나라가 향후 목성으로 탐사선을 보낸다고 가정하였을 경우, 행성 근접통과를 이용한 탐사선의 발사시기(Launch Window), 요구되는 발사 에너지(C3)값, 그리고 각각에 따른 궤적들을 산출하여 보았다. 이미 기술 개발을 완료한 국가들이 관련 기술의 제휴를 기피하고 있는 현 상황에서 이와 관련된 연구는 우주개발의 시대를 열고 있는 우리나라의 우주개발관련 기초 기술 분야를 위해 선행 연구되어야 할 부분이다. 기초 기술 분야를 위해 선행 연구되어야 할 부분이다.다.향을 해석하고 시뮬레이션 하였다.Device Controller)는 ECU로부터 명령어를 받아서 arm 및 safe 상태에 대한 텔리 메트리 데이터를 제공한다 그리고, SAR(Solar Array Regulator)는 ECU로부터 Bypass Relay 및 ARM Relay에 관한 명령어를 받아 수행되며 그에 따른 텔리 메트리 데이터를 제공한다. 마지막으로 EPS 소프트웨어를 검증하는 EPS Software Verification을 수행하였다 전력계 소프트웨어의 설계의 검증 부분은 현재 설계 제작된 전력계 .소프트웨어의 동작 특성 이 위성 의 전체 운용개념과 연계하여 전력계 소프트웨어가 전력계 및 위성체의 요구조건을 만족시키는지를 확인하는데 있다. 전력계 운용 소프트웨어는 배터리의 충ㆍ방전을 효율적으로 관리해 3년의 임무 기간동안 위성체에 전력을 공급할 수 있도록 설계되어 있다this hot-core has a mass of 10sR1 which i:s about an order of magnitude larger those obtained by previous studies.previous studies.업순서들의 상관관계를 고려하여 보다 개선된 해를 구하기 위한 연구가 요구된다. 또한, 준비작업비용을 발생시키는 작업장의 작업순서결정에 대해서도 연구를 행하여, 보완작업비용과 준비비용을 고려한 GMMAL 작업순서문제를 해결하기 위한 연구가 수행되어야 할 것이다.로 이루어 져야 할 것이다.태를 보다 효율적으로 증진시킬 수 있는 대안이 마련되어져야 한다고 사료된다.$\ulcorner$순응$\lrcorner$의 범위를 벗어나지 않는다. 그렇기 때문에도 $\ulcorner$순응$\lrcorner$과 $\ulcorner$표현$\lrcorner$의 성격과 형태를 외형상으로 더욱이 공간상에서는 뚜렷하

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.85-91
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• 2014

Background: Genome-wide association studies (GWAS) have identified various genetic susceptibility loci for breast cancer based mainly on European-ancestry populations. Differing linkage disequilibrium patterns exist between European and Asian populations. Methods: Ten SNPs (rs2075555 in COL1A1, rs12652447 in FBXL17, rs10941679 in 5p12/MRPS30, rs11878583 in ZNF577, rs7166081 in SMAD3, rs16917302 in ZNF365, rs311499 in 20q13.3, rs1045485 in CASP8, rs12964873 in CDH1 and rs8170 in 19p13.1) were here genotyped in 1009 Chinese females (487 patients with breast cancer and 522 control subjects) using the Sequenom MassARRAY iPLEX platform. Association analysis based on unconditional logistic regression was carried out to determine the odds ratio (OR) and 95% confidence interval (95% CI) for each SNP. Stratification analyses were carried out based on the estrogen receptor (ER) and progesterone receptor (PR) status. Results: Among the 10 SNPs, rs10941679 showed significant association with breast cancer when differences between the case and control groups in this Han Chinese population were compared (30.09% GG, 45.4% GA and 23.7% AA; P = 0.012). Four SNPs (rs311499, rs1045485, rs12964873 and rs8170) showed no polymorphisms in our study. The remaining five SNPs showed no association with breast cancer in the present population. Immunohistochemical tests showed that rs2075555 was associated with ER status; the AA genotype showed greater association with ER negative than ER positive (OR = 0.54, 95% CI, 0.29-0.99; P = 0.046). AA of rs7166081 was also associated with ER status, but showed a greater association with ER positive than negative (OR = 1.59, 95% CI = 1.04-2.44; P = 0.031). However, no significant associations were found among the SNPs and PR status. Conclusion: In this study using a Han Chinese population, rs10941679 was the only SNP associated with breast cancer risk, indicating a difference between European and Chinese populations in susceptibility loci. Therefore, confirmation studies are necessary before utilization of these loci in Chinese.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6103-6108
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• 2013

Objective: Excision repair cross-complementing group 6 (ERCC6) is a major component of the nucleotide excision repair pathway that plays an important role in maintaining genomic stability and integrity. Several recent studies suggested a link of ERCC6 polymorphisms with susceptibility to various cancers. However, the relation of ERCC6 polymorphism with gastric cancer (GC) risk remains elusive. In this sex- and age-matched case-control study including 402 GC cases and 804 cancer-free controls, we aimed to investigate the association between a potentially functional polymorphism (rs1917799 T>G) in the ERCC6 regulatory region and GC risk. Methods: The genotypes of rs1917799 were determined by Sequenom MassARRAY platform and the status of Helicobacter pylori infection was detected by enzyme-linked immunosorbent assay. Odd ratios (ORs) and 95% confidential interval (CI) were calculated by logistic regression analysis. Results: Compared with the common TT genotype, the ERCC6 rs1917799 GG genotype was associated with increased GC risk (adjusted OR=1.46, 95%CI: 1.03-2.08, P=0.035). When compared with (GT+TT) genotypes, the GG genotype also demonstrated a statistical association with increased GC risk (adjusted OR=1.38, 95%CI: 1.01-1.89, P=0.044). This was also observed for the male subpopulation (GG vs. TT: adjusted OR=1.71, 95%CI: 1.12-2.62, P=0.013; G allele vs. T allele: adjusted OR=1.32, 95%CI: 1.07-1.62, P=0.009). Genetic effects on increased GC risk tended to be enhanced by H. pylori infection, smoking and drinking, but their interaction effects on GC risk did not reach statistical significance. Conclusions: ERCC6 rs1917799 GG genotype might be associated with increased GC risk in Chinese, especially in males.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.249-255
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• 2017

BACKGROUND: Globally, mulberry (Morus sp.) is exploited for feeding leaf to silkworms in order to obtain silk fiber or for animal feedstock production. Also, mulberry fruit is known to a by-product that was produced from mulberry tree after harvesting leaves for silkworm rearing, as a yield and consumption of mulberry fruit was increased, it has been fixing to a newincome crop. Mulberry leaves and fruits are used for the health benefits of human beings. Mulberry contains various bioactive components, such as alkaloids and flavonoids. Mulberry flavonoids are an important part of the diet because of their effects on human nutrition. The flavonoids in mulberry leaf and fruit of 'Suhyang'(Morus alba L.) were determined. METHODS AND RESULTS: Flavonoids for mulberry leaf and fruit of 'Suhyang' were analysed using ultrahigh performance liquid chromatography coupled with diode array detection and quadrupole time-of-flight mass spectrometry (UPLC-DAD-QTOF/MS)technique. An UPLC-DAD-QTOF/MS system was used, and identification of mulberry leaves constituents was carried out on the basis of the complementary information obtained from LC spectra, MS ions, and MS/MS fragments. The mulberry leaf (16 flavonoids) and fruit (9 flavonoids) were isolated and analyzed from Suhyang using UPLC-DAD-QTOF/MS chromatogram. To the best of our knowledge, Quercetin 3-O-(6"-O-malonyl) glucoside and quercetin 3-O-rutinoside (rutin) was detected on the highest content in leaf and fruit, respectively and further research will be devoted to evaluate their biological activity. CONCLUSION: Obtaining information about the concentration of functional materials in mulberry leaves could contribute to the development and promotion of processed, functional products and offer possible industrial use of 'Suhyang', holding promises to enhance the overall profitability of sericulture.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.424-429
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• 2016

Globally, obesity has been recognized as a serious health problem. Recently, slimming foods for weight loss and maintenance were found to contain anti-obesity drugs, their analogues, and prohibited ingredients. To avoid inspections by the Government, structurally modified analogs have been continuously synthesized. For rapid determination of adulterated slimming products, we simultaneously analyzed 21 illegal compounds using liquid chromatography (LC) equipped with photo diode array, and LC coupled with tandem mass spectrometry. The validation of the method was performed with regard to selectivity, linearity, limit of detection, limit of quantification, precision, and accuracy. We purchased 128 samples from the Korean market and online sources in the year 2015. In 31 samples, 3 illegal compounds were detected as follows: 9.9-135.3 mg/g of sibutramine, 0.2-17.5 mg/g of yohimbine, and 1.8 mg/g of icariin. This simultaneous detection method might prove to be a simple and rapid analysis for monitoring illegal compounds in slimming foods.

• Journal of Marine Bioscience and Biotechnology
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• v.15 no.2
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• pp.82-89
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• 2023

Microalgae, as photosynthetic organisms, possess the ability to produce a diverse array of bioactive compounds. This study focused on the transformant Chlamydomonas reinhardtii dZL and subjected it to cultivation under varying light intensities (60, 120, 180, and 240 µmol/m²/s). Our aim was to assess the impact of light intensity on both microalgal biomass and carotenoid production. The cultivation took place in 80 mL bubble column photobioreactors, specifically the Multi-cultivator. Notably, the culture exposed to 240 µmol/m²/s exhibited the most rapid cell growth, surpassing even the cell concentration achieved at 180 µmol/m²/s by day 8. A detailed analysis of the specific irradiance rate over time unequivocally revealed a sharp decline in growth rates when the rate fell below 2 × 10^-10 µmol/cell/s. Although the culture with 60 µmol/m²/s yielded the highest carotenoid content (1.2% of dry weight), the culture exposed to 240 µmol/m²/s recorded the highest carotenoid concentration at 8.9 mg/L owing to its higher biomass. Our findings reveal the critical importance of maintaining a specific irradiance rate above 2 × 10^-10 µmol/cell/s to enhance biomass and carotenoid productivity. This study lays the groundwork for defining optimal light intensity conditions applicable to mass culture systems, with the objective of augmenting C. reinhardtii biomass and optimizing carotenoid productivity.

• Journal of Distribution Research
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• v.15 no.4
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• pp.61-85
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• 2010

Introduction: Diffusion is process by which an innovation is communicated through certain channel overtime among the members of a social system(Rogers 1983). Bass(1969) suggested the Bass model describing diffusion process. The Bass model assumes potential adopters of innovation are influenced by mass-media and word-of-mouth from communication with previous adopters. Various expansions of the Bass model have been conducted. Some of them proposed a third factor affecting diffusion. Others proposed multinational diffusion model and it stressed interactive effect on diffusion among several countries. We add a spatial factor in the Bass model as a third communication factor. Because of situation where we can not control the interaction between markets, we need to consider that diffusion within certain market can be influenced by diffusion in contiguous market. The process that certain type of retail extends is a result that particular market can be described by the retail life cycle. Diffusion of retail has pattern following three phases of spatial diffusion: adoption of innovation happens in near the diffusion center first, spreads to the vicinity of the diffusing center and then adoption of innovation is completed in peripheral areas in saturation stage. So we expect spatial effect to be important to describe diffusion of domestic discount store. We define a spatial diffusion model using multinational diffusion model and apply it to the diffusion of discount store. Modeling: In this paper, we define a spatial diffusion model and apply it to the diffusion of discount store. To define a spatial diffusion model, we expand learning model(Kumar and Krishnan 2002) and separate diffusion process in diffusion center(market A) from diffusion process in the vicinity of the diffusing center(market B). The proposed spatial diffusion model is shown in equation (1a) and (1b). Equation (1a) is the diffusion process in diffusion center and equation (1b) is one in the vicinity of the diffusing center. $$\array{{S_{i,t}=(p_i+q_i{\frac{Y_{i,t-1}}{m_i}})(m_i-Y_{i,t-1})\;i{\in}\{1,{\cdots},I\}\;(1a)}\\{S_{j,t}=(p_j+q_j{\frac{Y_{j,t-1}}{m_i}}+{\sum\limits_{i=1}^I}{\gamma}_{ij}{\frac{Y_{i,t-1}}{m_i}})(m_j-Y_{j,t-1})\;i{\in}\{1,{\cdots},I\},\;j{\in}\{I+1,{\cdots},I+J\}\;(1b)}}$$ We rise two research questions. (1) The proposed spatial diffusion model is more effective than the Bass model to describe the diffusion of discount stores. (2) The more similar retail environment of diffusing center with that of the vicinity of the contiguous market is, the larger spatial effect of diffusing center on diffusion of the vicinity of the contiguous market is. To examine above two questions, we adopt the Bass model to estimate diffusion of discount store first. Next spatial diffusion model where spatial factor is added to the Bass model is used to estimate it. Finally by comparing Bass model with spatial diffusion model, we try to find out which model describes diffusion of discount store better. In addition, we investigate the relationship between similarity of retail environment(conceptual distance) and spatial factor impact with correlation analysis. Result and Implication: We suggest spatial diffusion model to describe diffusion of discount stores. To examine the proposed spatial diffusion model, 347 domestic discount stores are used and we divide nation into 5 districts, Seoul-Gyeongin(SG), Busan-Gyeongnam(BG), Daegu-Gyeongbuk(DG), Gwan- gju-Jeonla(GJ), Daejeon-Chungcheong(DC), and the result is shown