• 대한전자공학회논문지SD
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• 제43권12호
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• pp.55-64
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• 2006

본 설계에서는 무선 랜 등 최첨단 무선 통신 및 고급영상 처리 시스템과 같이 고해상도와 높은 신호처리속도, 저전력 및 소면적을 동시에 요구하는 고성능 집적시스템 응용을 위해 기존의 보정기법을 사용하지 않는 14b 70MS/s 0.13um CMOS A/D 변환기(Analog-to-Digital Converts- ADC)를 제안한다. 제안하는 がU는 중요한 커패시터 열에 인접신호에 덜 민감한 3차원 완전 대칭 구조의 레이아웃 기법으로 소자 부정합에 의한 영향을 최소화하였고, 3단 파이프라인 구조로 고해상도와 높은 신호처리속도와 함께 전력 소모 및 면적을 최적화하였다. 입력 단 SHA 회로에는 Nyquist 입력에서도 14비트 이상의 정확도로 신호를 샘플링하기 위해 게이트-부트스트래핑 (gate-bootstrapping) 회로를 적용함과 동시에 트랜스컨덕턴스 비율을 적절히 조정한 2단 증폭기를 사용하여 14비트에 필요한 높은 DC전압 이득을 얻음과 동시에 충분한 위상 여유를 갖도록 하였으며, 최종 단 6b flash ADC에는 6비트 정확도 구현을 위해 2단 오픈-루프 오프셋 샘플링 기법을 적용하였으며, 기준 전류 및 전압 발생기는 온-칩으로 집적하여 잡음을 최소화하면서 필요시 선택적으로 다른 크기의 기준 전압 값을 외부에서 인가할 수 있도록 하였다. 제안하는 시제품 ADC는 0.13um CMOS 공정으로 요구되는 2.5V 전원 전압 인가를 위해 최소 채널길이는 0.35um를 사용하여 제작되었으며, 측정된 DNL 및 INL은 14비트 해상도에서 각각 0.65LSB, 1.80LSB의 수준을 보이며, 70MS/s의 샘플링 속도에서 최대 SNDR 및 SFDR은 각각 66dB, 81dB를 보여준다. 시제품 ADC의 칩 면적은 $3.3mm^2$이며 전력 소모는 2.5V 전원 전압에서 235mW이다.

• 자원환경지질
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• 제16권2호
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• pp.65-78
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• 1983

This report deals with the sedimentological study of the littoral sand of beaches in the Busan area. The purpose of this report is to know the grain size, mineralogical composition, heavy mineral and clay mineral of the beach sands, and gravity measurements of the Nagdong River Deltas. 1) As a whole, the littoral sand of the beaches are composed of uniformly medium grained, moderately sorted and nearly symmetrical. The barrier sand of the Nagdong Estuary is composed of fine grained, well sorted and nearly symmetrical. 2) The littoral sand of the beaches is transported by saltation and rolling. The barrier sand of the Nagdong Estuary is transported by suspension and saltation. 3) In the littoral sand of the beaches, the ratio of feldspar to quartz is 1 :2.31 and in the barrier sand of the Nagdong Estuary 1:1.40. 4) The content of heavy mineral of samples ranges from 0.54 to 3.87 %. The principal heavy minerals are hornblende, pyroxene, epidote, garnet, leucoxene, zircon, apatite, magnetite, hematite and ilmenite with minor accessories of rutile and olivine. 5) The x-ray diffraction analysis of the clay mineral informs the existence of quartz, feldspar, kaolinite and montmorillonite. The montmorillonite is considered to have been derived from the alteration of acidic volcanic rocks. 6) To determine the depositional structure of the Nagdong Estuary, Gravity measurements were made. Free air anomaly ranges from 14.5 mgal to 33.5 mgal and Bouguer anomaly ranges from 14.3 to 23.5 mgal and both are closely related to the topography. According to the interpreted layer structure, the upper layer composing sand, silt and clay, the intermediate layer composing sand with gravel, the lower layer composing weathered and soft rock, and bed rock composing hornfels or andesite. 7) The depositional environments of the study, the littoral area is dominated by the marine environment and the Nagdong Estuary by the mixed environment.

• 대한한의진단학회지
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• 제17권2호
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• pp.112-121
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• 2013

Objectives This study analyze the correlation between iris markings and the obesity level shown in body composition indices. And It quantitatively evaluates iris markings according to the level of obesity to improve a clinical application plan for the iris analysis. Methods This study analyzed the iris and body composition through the quantization of iris markings for 28 female patients. It calculated descriptive statistics by using SPSS 13.0 and investigated correlation coefficients of non-parametric Spearman in order to analyze the relation between iris markings and body composition indices. Results Considering the correlation between iris markings and body composition indices, an area of the pupil had a significant positive correlation with height and with fat-free amount such as body water, protein, and minerals. BMI showed significant positive correlations with the length of the autonomic nerve wreath and the ratio of the autonomic nerve wreath, and the area of the autonomic nerve wreath. Moreover, the number of lacunas in the pancrea area had a significant positive correlation with weight and BMI. Conclusions This study objectifies the quantification of iris markings to identify the correlation between iris markings and the level of obesity. The study results will be used as a basic data to make standards for the diagnosis of obesity, the treatment of related diseases, and the diagnosis of iris markings for prevention.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.232-232
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• 2010

Recently light emitting diodes (LEDs) have been expected as the new generation light sources because of their advantages such as small size, long lifetime and energy-saving. GaN, as a wide band gap material, is widely used as a material of LEDs and GaN nanorods are the one of the most widely investigated nanostructure which has advantages for the light extraction of LEDs and increasing the active area by making the cylindrical core-shell structure. Lately GaN nanorods are fabricated by various techniques, such as selective area growth, vapor-liquid-solid (VLS) technique. But these techniques have some disadvantages. Selective area growth technique is too complicated and expensive to grow the rods. And in the case of VLS technique, GaN nanorods are not vertically aligned well and the metal catalyst may act as the impurity. So we just tried to grow the GaN nanorods on Si substrate without catalyst to get the vertically well aligned nanorods without impurity. First we deposited the AlN buffer layer on Si substrate which shows more vertical growth mode than sapphire substrate. After the buffer growth, we flew trimethylgallium (TMGa) as the III group source and ammonia as the V group source. And during the GaN growth, we kept the ammonia flow stable and periodically changed the flow rate of TMGa to change the growth mode of the nanorods. Finally, as the optimization, we changed the various growth conditions such as the growth temperature, the working pressure, V/III ratio and the doping level. And we are still in the process to reduce the diameter of the nanorods and to extend the length of the nanorods simultaneously. In this study, we focused on the shape changing of GaN nanorods with different growth conditions. So we confirmed the shape of the nanorods by scanning electron microscope (SEM) and carried out the Photoluminescence (PL) measurement and x-ray diffraction (XRD) to examine the crystal quality difference between samples. Detailed results will be discussed.

• Asian Pacific Journal of Cancer Prevention
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• 제16권10호
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• pp.4363-4368
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• 2015

Background: The tumor-stroma ratio (TSR) represents the percentage of neoplastic cell components compared to the combined area of neoplastic cells and the surrounding tumor-induced stroma. A low TSR (predomination of stromal component) has been demonstrated to be an independent adverse prognostic factor in cancers of several organs. In cervical carcinoma patients, TSR has been evaluated in only one previous study with different histological types. The present study aimed to assess the prognostic value of TSR in early stage cervical cancer patients with adenocarcinoma histology only. Materials and Methods: Histological slides of patients with early stage (IB-IIA) cervical adenocarcinoma who underwent surgical treatment between January 2003 and December 2011 were reviewed. Patients who had received preoperative chemotherapy were excluded. TSR was categorized as low (<50%) and high (${\geq}50%$). Correlations between TSR and clinicopathological variables were evaluated. Prognostic values of TSR and other variables were estimated using Cox's regression. Results: Of 131 patients; 38 (29.0%) had low TSR and 93 (71.0%) had high TSR. The patients with low TSR had significantly higher proportions of deep cervical stromal invasion (outer third of wall, p=0.011; residual stroma less than 3 mm, p=0.008) and parametrial involvement (p=0.026). Compared to the patients with high TSR, those with low TSR tended to have lower 5-year disease-free survival rate (83.8% versus 88.9%) and overall survival rate (85.6% versus 90.3%), although the differences were not statistically significant. Low TSR was significantly associated with decreased overall survival in univariate analysis (HR 2.7; 95% CI 1.0-7.0; p=0.041), but not in multivariate analysis. TSR was not significantly associated with decreased disease-free survival. Conclusions: Low TSR is associated with decreased overall survival in patients with early stage cervical adenocarcinoma treated by surgery. However, it was not found to be an independent prognostic predictor in this study.

• 한국항공우주학회지
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• 제47권9호
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• pp.607-616
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• 2019

항공우주비행체 정적구조시험을 위한 과하중 방지를 위해 사용되는 하중제한밸브(LLV)의 파일럿 스테이지의 주요 구성품들에 대한 자유물체도 분석을 수행하였다. 이 분석을 통하여 유압작동기의 동일한 힘에서 일관성있게 포펫 개방되도록 하기 위해서는 파일럿스테이지에 있는 두 포펫의 직경비($(D_2)^{ten}/D_2)^{comp}$)가 작동기의 피스톤 면적비($A_{comp}/A_{ten}$)와 동일해야만 한다는 것을 보였다. 실험실에서 외산으로 수입하여 사용하고 있는 4개의 서로 다른 하중제한밸브의 포펫들 형상을 측정하고 대응되는 4개의 다른 용량을 갖는 유압작동기들의 피스톤 면적비들로부터 위의 분석결과가 타당함을 확인하였다. 두 개의 다른 파일럿스테이지로 수행한 "조절자 분해능시험들"의 결과들로부터 조절자 각 회전에서 얻은 Fi(포펫개방 순간의 작동기 힘)의 최대 표준편차는 각 평균값으로부터 0.3KN이고 표준편차를 각 평균값으로 나눈 무차원값으로 분석하면 최대편차는 3.7%이다. 이 결과로 부터 동일 포펫 직경비를 갖는 두 개의 파일럿스테이지들의 포펫은 각 조절자 회전에 대해 Fi/(평균 Fi) 값이 +/- 3.7% 범위에서 일관성 있게 개방되고 있음을 확인하였다. 위의 편차는 포펫 O-링의 마찰력으로부터 유발되는 것임을 보였다. 부가적으로 파일럿스테이지의 다른 주요부품인 포펫 스프링과 조절자의 주요설계인자들도 식별하였고 이들의 결정과정도 본 연구에서 보였다.

• 대한본초학회지
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• 제29권1호
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• pp.35-43
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• 2014

Objectives : We investigated the effects of gambigyeongsinhwan(GGH)(1) on body weight and non-alcoholic fatty liver disease(NAFLD) examined whether blood total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels and hepatic lipid accumulation are inhibited by it in high fat diet-fed obese male mice. Methods : 8 weeks old, high fat diet-fed obese male mice were divided into 5 groups: C57BL/6N normal, control, GGH(1)-1, GGH(1)-2 and GGH(1)-3. After mice were treated with GGH(1) for 8 weeks, we measured body weight gain, food intake, feeding efficiency ratio, fat weight, plasma ALT, leptin and lipid levels. We also did histological analysis for liver and fat on the mice. Results : Compared with controls, GGH(1)-treated mice had lower body weight gain and adipose tissue weight, the magnitudes of which were prominent in GGH(1)-3. Compared with controls, GGH(1)-treated mice had lower feeding efficiency ratio and blood leptin level, the magnitudes of which was prominent in GGH(1)-3. Compared with controls, GGH(1)-treated mice had lower blood plasma total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels. Compared with controls, GGH(1)-3 treated mice had lower blood plasma ALT concentration. Consistent with their effects on body weight gain, the size of adipocytes were significantly decreased by GGH(1), whereas the adipocyte number per unit area was significantly increased, suggesting that GGH(1) decreased the number of large adipocytes. Hepatic lipid accumulation was decreased by GGH(1). Conclusions : In conclusion, these results suggest that GGH(1) exhibits anti-obesity effects through the modulation of feeding efficiency ratio and plasma obesity parameters. Moreover, it seems that GGH(1) also contributes to improve NAFLD through the regulation of plasma ALT and hepatic triglyceride accumulation.

• 동의생리병리학회지
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• 제27권1호
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• pp.99-106
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• 2013

We investigated the effects of gambigyeongsinhwan(GGH)(4) on body weight and non-alcoholic fatty liver disease(NAFLD) examined whether blood total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels and hepatic lipid accumulation are inhibited by it in high fat diet-fed obese male mice. 8 weeks old, high fat diet-fed obese male mice were divided into 5 groups: C57BL/6N normal, control, GGH(4)-1, GGH(4)-2 and GGH(4)-3. After mice were treated with GGH(4) for 8 weeks, we measured body weight gain, food intake, feeding efficiency ratio, fat weight, plasma ALT, leptin and lipid levels. We also did histological analysis for liver and fat on the mice. Compared with controls, GGH(4)-treated mice had lower body weight gain and adipose tissue weight, the magnitudes of which were prominent in GGH(4)-2. Compared with controls, GGH(4)-treated mice had lower feeding efficiency ratio and blood leptin level, the magnitudes of which was prominent in GGH(4)-2. Compared with controls, GGH(4)-treated mice had lower blood plasma total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels. Compared with controls, GGH(4)-2 treated mice had lower blood plasma ALT concentration. Consistent with their effects on body weight gain, the size of adipocytes were significantly decreased by GGH(4), whereas the adipocyte number per unit area was significantly increased, suggesting that GGH(4) decreased the number of large adipocytes. Hepatic lipid accumulation was decreased by GGH(4). In conclusion, these results suggest that GGH(4) exhibits anti-obesity effects through the modulation of feeding efficiency ratio and plasma obesity parameters. Moreover, it seems that GGH(4) also contributes to improve NAFLD through the regulation of plasma ALT and hepatic triglyceride accumulation.

• 한국항만경제학회지
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• 제26권1호
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• pp.195-221
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• 2010

본 연구는 글로벌 물류환경의 변화에 따른 군산항만의 향후 대응방안을 제시하는데 있어 군산 항만의 항세와 시설의 현황 및 그 한계를 분석하고 향후 발전 전략을 모색하여 보았다. 연구결과 군산항의 물류인푸라 확충을 위해서는 배후지인 자유무역지대와 새만금군산자유구역 등의 장점을 최대한 활용하여 군산항을 수출입 거점 전략항으로 육성하여야 할 것이다. 특히 중국과의 지경학적 우위를 확보하고 환황해권역의 대중국 역내분업과 경쟁 가능한 업종을 배후지에 유치하여 지역경제의 획기적인 혁신을 꾀하는 것도 중요하다. 따라서 투자의 활성화와 배후 산업의 신기술 도입을 위해 외자유치가 선행되어야 할 것이다. 군산항의 경쟁력확보를 위해서는 물류비를 낮추는 즉, 규모의 경제를 실현 시키는 방안도 강구되어야만 한다. 본 연구에서 물류환경에 적극적으로 대응하기 위해서는 첫째, 기술, 마케팅, 무역정보 활용과 전문기술의 공유 등을 통한 항만간 협력체제 구축을 모색할 필요가 있다. 둘째, 토사로 인한 수심의 피해를 최소화하기 위한 방책을 강구하고, 셋째, 중국의 성장 에너지를 군산항으로 유인하기 위해서는 환황해권의 항만 간 대중국 물류네트워크를 구축하는 일이 시급하다. 넷째, 글로벌 물류기업의 고부가가치 화물유치를 위해 기반시설 확충과 공동물류센터 건립하는 방안도 강구해 보는 것도 바람직하다. 따라서 군산항이 동북아 물류허브항 으로서 역할을 다하려면 군산을 유비쿼터 시티와 첨단물류시스템이 결합된 유-물류 군산시티로 탈바꿈하는 것도 바람직하다.

• 대한지역사회영양학회지
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• 제11권2호
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• pp.279-288
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• 2006

The role of free radicals in the progression of many diseases and aging has been given a great attention and total antioxidant status (TAS) has shown to be reduced with aging. The incidence of hypertension has shown to be relatively high in the aged population, and it is known to be associated with increased obesity and oxidative stress. The aim of this study was to examine the obesity indices and the total antioxidant status in hypertensive elderly (64y$\alpha$-tocopherol, $\beta$-carotene and ascorbic acid did not show their significant correlations with TAS. These results showed that the hypertensive elderly are prone to be obese and to have increased TAS. Due to unknown factors affecting TAS values, measurement of plasma TAS as a sole indicator of total antioxidant capacity is limited to fully understanding changes in the body's free radical trapping power. However, the results from the current study may suggest that hypertension and/or obesity might increase oxidative stress, followed by increased the body's total antioxidant defense system.