• 한국통신학회논문지
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• 제29권2A호
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• pp.181-186
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• 2004

2003년 세계전파통신회의(WRC-2003)에서 지상망과 고밀도 고정위성업무(HDFSS:High-Density fixed satellite service)의 주파수 공유 및 HDFSS용 하향링크 후보대역 선정문제로 이슈화된 40 ㎓ 대역에서 정지위성망과 지상망간 주파수 공유에 따른 간섭 영향을 우리나라에서 운용하는 것으로 설정해 분석하였다. 40 ㎓ 대역 정지위성망과 지상망의 전형적인 특성 파라미터를 이용하여 시뮬레이션한 결과, 우리나라 지상 고정업무 무선국의 안테나가 같은 40 ㎓ 대역을 공유하는 정지위성을 향할 경우, 40 ㎓ 지상망의 운용특성들이 맞물려. 간섭을 받을 수 있는 최악의 특정 조건이 이루어질 수 있음을 보았다. 이러한 상황은 고층건물이 밀집된 지역에 지상망을 설치할 때 발생할 수 있으므로. 향후 40 ㎓ 대역의 고밀도 지상고정업무(HDFS :High-Density fixed service) 무선국들이 설치될 때, 정지궤도 지향을 피하는 간섭경감기법이 강구되어야 할 것으로 보인다.

• 대한지역사회영양학회지
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• 제18권2호
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• pp.177-186
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• 2013

The purpose of this study was to investigate factors associated with Bone Mineral Density (BMD) in Korean postmenopausal women. The data from 2008-2010 Korean National Health and Nutrition Examination Survey (KNHANES) were used for data analysis. Subjects were 2,701 postmenopausal women aged ${\geq}50$ years. BMDs at whole body, total femur, femoral neck, and lumbar spine were measured by Dual-energy X-ray absorptiometry (DXA). Dietary data from 24-hour dietary recall and a food frequency questionnaire containing 63 food items were used. The proportions of osteopenia at total femur, femoral neck, and lumbar spine were 37.4%, 54.5%, and 45.4%, respectively. The proportions of osteoporosis at total femur, femoral neck, and lumbar spine were 6.2%, 25.6%, and 34.3%, respectively. Age, anthropometric index including height, weight, and Body Mass Index (BMI), parathyroid hormone, and physical activity were related to BMD, but the relationships were site specific. Total femur BMD was explained by age, weight, parathyroid hormone and intakes of carbohydrate and fruits. Femoral neck BMD was related to age, weight, parathyroid hormone and intakes of riboflavin and fruits. Lumbar spine BMD was associated with age, weight, milk and dairy products, calcium intake, and exercise. These results indicated that adequate intakes of milk and dairy products, fruits, carbohydrate, calcium, riboflavin and exercise as well as weight maintenance might play an important role in maintaining optimum bone health in Korean postmenopausal women.

• 대한지역사회영양학회지
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• 제9권5호
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• pp.644-653
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• 2004

This study was conducted to detennine the dietary and lifestyle factors related to bone the mineral density (BMD) of postmenopausal women with decreased BMD. The subjects (N =163) were recruited from women who visited a orthopedic clinic for BMD check up. A trained dietition interviewed subjects individually to obtain data about dietary behavior, consumption frequency of foods known as main dietary source of calcium and potassium, and clinical symptoms. The risk factors were identified by correlation and multiple regression analysis of variables. The mean age of the subjects was 66.8 yews. Most of them showed low levels of education and monthly income. The mean age of menarche and menopause were 17.2 and 48 year, respectively. The mean menopause duration was 18.7 year. Most of the consumption of calcium was centered to vegetable foods. Education level were positively correlated (r =0.272, P < 0.05) with BMD whereas age, menarch age, menopause duration, number of children were negatively correlated (r=-0.355, r=-0.240, r=-0.283, r=-0.193, respectively, p < 0.05) with BMD. The consumption of soybean, radish were positively correlated (r=0.187, r=0.158, respectively, p < 0.05) with BMD. Potassium intake with rice showed significantly negative correlation with BMD (r =-0.189, P < 0.05), but calcium intake with brown seaweeds, bean sprouts were positively correlated (r =0.247, r =0.254 respectively, p < 0.05) with BMD. Protein intake with roasted pork was also positively correlated (r =0.216, P < 0.05) with BMD. Multiple regression analysis showed that the most prominent negative predictor influencing the BMD was age. Minor negative factors influencing the BMI were age of menarche, potassium intake from rice. But the significantly positively factors influencing the BMD were consumption of radish and soybean intake, education, and protein intake with roasted pork. In conclusion brown seaweeds, radish or soybeans can be promoted as cheap foods replacing milk and milk products for menopausal women with low income.

• The Korean Journal of Physiology and Pharmacology
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• 제19권4호
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• pp.357-363
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• 2015

The purpose of this study was to compare the inhibitory effect of bevacizumab on human Tenon's fibroblasts (HTFs) cultured from primary and recurrent pterygium. Cultured HTFs were exposed to 2.0, 5.0, 7.5, and 15.0 mg/mL concentration of bevacizumab for 24 hours. The 3-[4,5-dimethylthiazol- 2-yl]-2,5-diphenyl tetrazolium bromide and lactate dehydrogenase leakage assays were then performed to assess fibroblast metabolism and viability. The matrix metalloproteinase (MMP), procollagen type I C terminal propeptide (PIP), and laminin immunoassays were performed to examine extracellular matrix production. Changes in cellular morphology were examined by phase-contrast and transmission electron microscopy. Both metabolic activity and viability of primary and recurrent pterygium HTFs were inhibited by bevacizumab in a dose-dependent manner, especially at concentrations greater than 7.5 mg/mL. Both types of HTFs had significant decreases in MMP-1, PIP, and laminin levels. Distinctly, the inhibitory effect of bevacizumab on MMP-1 level related with collagenase in primary pterygium HTFs was significantly higher than that of recurrent pterygium. Significant changes in cellular density and morphology both occurred at bevacizumab concentrations greater than 7.5 mg/mL. Only primary pterygium HTFs had a reduction in cellular density at a bevacizumab concentration of 5.0 mg/mL. Bevacizumab inhibits primary and recurrent pterygium HTFs in a dose-dependent manner, especially at concentrations greater than 7.5 mg/mL. As the primary HTFs produces larger amounts of MMP-1 compared to recurrent HTFs, significant reduction in MMP-1 level in primary pterygium HTFs after exposure to bevacizumab is likely to be related to the faster cellular density changes in primary pterygium HTFs.

• 한국세라믹학회지
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• 제38권11호
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• pp.973-979
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• 2001

Sn을 도핑한 In$_2$O$_3$(ITO) 박막을 R.F. 마그네트론 반응성 스퍼터링법에 의해서 증착하였다. 동일한 마그네트론 스퍼터링 조건에서 증착위치에 따른 ITO 박막의 저항, 자유 전하 농도 및 이동도 전기적 특성을 조사하였다. 동일한 마그네트론 스퍼터링 조건임에도 불구하고, ITO 박막의 전기적 특성은 증착위치에 따라 불균질성을 나타내었다. 타겟의 중심에 위치한 기판위에 증착된 ITO 박막의 저항은 최소 값인 2~4$\times$$10^{-4}$ $\Omega$.cm인 반면, 중심에서 멀어질수록 박막의 전기 저항은 대칭적으로 증가하였다. ITO 박막의 밀도 측정 결과도 중심에서 이론 밀도 값의 97%에 해당하는 7.0g/$cm^3$를 나타내나, 위치가 중심에서 멀어질수록 박막의 밀도가 대칭적으로 감소하였다. ITO 박막에서 이동도와 전도도는 밀도에 직접적으로 영향을 받는 것이 실험적으로 확인되었다. ITO 박막의 밀도가 7.0g/$cm^3$(이론 밀도의 97%)인 경우, 자유행정거리와 입자크기(=주상의 직경)가 동일한 값을 가지나, 밀도가 이 보다 감소하면 자유행정거리와 입자크기의 차이는 더욱 증가하였다. 이 결과는 ITO 박막의 밀도가 7.0g/$cm^3$인 경우는 입계가 자유 전자의 전도에 중요한 산란 원으로 작용하는 반면, 그 외의 경우는 결정 내의 공격자점, 공공, 기공 등이 다른 산란 원으로 작용하고 있다는 것을 나타낸다.

• 대한방사선기술학회지:방사선기술과학
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• 제28권3호
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• pp.235-239
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• 2005

청소년기에 형성된 골밀도는 25세에서 35세 전후로 최고치가 되며, 형성된 골밀도는 중년기와 노년기에 감소된다. 골밀도 감소는 골다공증의 발생과 골절 위험성 증가 등을 유발하여 사회적인 건강문제로 대두되고 있다. 골다공증은 사전 예방이 매우 중요하며, 골밀도가 감소되는 중년기 이후보다 골밀도가 형성되고 최고로 발달되는 시기인 청년기에 적극적인 관리와 예방이 중요하다. 따라서 본 연구는 대학생의 골밀도 상태와 생활습관 및 신체활동과의 관계를 파악하여 골밀도 향상을 위한 자료 개발에 도움이 되는 시사점을 도출하고자 일부 대학생 119명을 대상으로 골밀도 측정과 생활습관에 대한 설문을 실시하여 다음과 같은 결론을 도출하였다. 첫째, 대상자의 일반적 골밀도 상태는 정상 88명(73.9%), 골감소증 29명(24.4%), 골다공증 2명(1.7%)으로 정상이 가장 높게 나타났으나 골감소증도 다소 높게 나타났다. 둘째, 성별에 따른 생활습관과의 관계에서는 음주 경험, 흡연경험, 운동 경험이 통계적으로 유의하게 나타났다. 음주경험, 흡연경험, 운동경험이 있는 경우는 남학생 군이 모두 높게 나타났다. 셋째, 일반적 특성에 따른 골다공증 상태와의 관계에서는 성별과 흡연경험이 집단 내에서 통계적으로 유의한 차이를 나타냈다. 성별에서는 남학생에게서는 골감소증이 가장 높게 나타났고, 여학생은 정상이 높게 나타났으며 이는 통계적으로 유의하였다. 흡연경험에 따른 골다공증 상태에서는 흡연경험이 없는 군에서는 정상이 가장 높게 나타났고, 흡연경험이 있는 군에서는 골감소증이 가장 높게 나타났으며 통계적으로 유의하였다.

• 대한예방한의학회지
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• 제22권1호
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• pp.107-127
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• 2018

Objectives : The present study investigated the anti-obese and blood flow improvement activities of aqueous extracts of ginseng berry (GBe) on the mild diabetic obese mice as compared with metformin. Methods : After end of 56 days of continuous oral administrations of GBe 150, 100 and 50 mg/kg, or metformin 250 mg/kg, anti-obese and blood flow improvement effects - the changes of body weights, body and abdominal fat density by in live dual-energy x-ray absorptionmetry (DEXA), tail bleeding time, prothrombin time (PT), activated partial thromboplastin time (aPTT), serum total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL) and high density lipoprotein (HDL) levels, aorta and serum cyclic guanosine monophosphate (cGMP), nitric oxide (NO) and endothelin (ET)-1 levels, aorta phosphorylated PI3K (pPI3K), phosphorylated Akt (pAkt) and phosphorylated p38 MAPK (pp38 MAPK) levels were systemically analyzed. In addition, aorta vascular dilation and constriction related gene mRNA expressions - PI3K, Akt, eNOS, p38 MAPK and ET-1 were also analyzed by realtime RT-PCR. Results : The obesity and related blood flow impairment, induced by 84 days of continuous HFD supply, were significantly inhibited by 56 days of continuous oral treatment of GBe 150, 100 and 50mg/kg, dose-dependently, and they also dramatically normalized the changes of the aorta vascular dilation and constriction related gene mRNA expressions, also dose-dependently. Especially, GBe 150 mg/kg constantly showed favorable inhibitory activities against type II diabetes related obesity and vascular disorders through PI3K/Akt pathway and p38 MAPK mediated cGMP, NO and ET-1 expression modulatory activities, as comparable to those of metformin 250 mg/kg in HFD mice. Conclusion : By assessing the key parameters for anti-obese and blood flow improvement activities on the HFD-induced mild diabetic obese mice, the present work demonstrated that GBe 150, 100 and 50 mg/kg showed favorable anti-obese and blood flow improvement effects in HFD-induced type II diabetic mice, through PI3K/Akt pathway and p38 MAPK mediated cGMP, NO and ET-1 expression modulatory activities.

• 동의생리병리학회지
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• 제28권2호
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• pp.206-216
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• 2014

To investigate the anti-photoaging effect of fermented Red Ginseng(RG) in SKH-1 mice. We examined the effects of extracts of non-fermented RG(NRG group), fermented RG(FRG group) and fortified fermented RG(FFRG group) on skin wrinkles formation, histological changes related to the number of epidermal cell layers, epidermal thickness, neutrophil infiltration into dermis, degradation of collagen fibers, and the number of mast cells, and immunohistochemical changes related to cytokines and enzymes in photoaging skin caused by UVB irradiation of SKH-1 mice. The oral administration(300 mg/Kg B.W./day) and topical application($100{\mu}{\ell}/mouse/day$) of extracts of NRG, FRG and FFRG inhibited increases in epidermal thickness and wrinkle formation compared to control group in dorsal skin induced by UVB irradiation. We observed more increased stainability of acid fuschin and aniline blue in dermis of FFRG group than those of other groups. Furthermore, NRG, FRG and FFRG prevented the disruption of collagen fibers within papillary layer of dermis, and decreased number of mast cells in the dorsal skins induced by UVB irradiation. We observed fine wrinkle formation in FFRG group. Treatment with NRG, FRG and FFRG decreased immunohistochemical density of myeloperoxidase related to inflammation in the photoaging skin. We observed more decreased immunohistochemical density of myeloperoxidase in FFRG group than those of other groups. Immunohistochemical density of PCNA and Ki-67 in FFRG group was more decreased than those of other groups. Our study suggests that fermented red ginseng extracts participates in inhibitory effects in the morphological processes related to photoaging skin on UVB irradiated SKH-1 mice.

• Journal of Yeungnam Medical Science
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• 제29권2호
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• pp.73-76
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• 2012

More and more children are becoming obese and overweight due to several factors that include a high energy density in the diet (a high fat intake) and low energy expenditure. Consequently childhood obesity is becoming a significant health problem. Fat tissue releases many cytokines such as resistin, tumor necrosis factor-${\alpha}$, leptin, interleukin-6. These adipocytokines induce obesity-related insulin resistance. Insulin resistance is a key component of obesity-related metabolic problems such as hypertension, type 2 diabetes mellitus, dyslipidemia, non-alcoholic steatohepatitis, acanthosis nigricans and polycystic ovarian syndrome. This review article focused on insulin resistance and its related metabolic diseases.

• 한국수학교육학회지시리즈A:수학교육
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• 제38권1호
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• pp.77-85
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• 1999

In this paper, we analyze strategies and error patterns in solving word problems of linear equation for middle school students. From a test conducted to the sampled 106 second grade middle school students, we obtain the following results: (1)The most difficult types of word problem are velosity and density related problems. The second one is length related problems and the easist one is number related problems. (2)Regardless of the types of word problem, the most familiar strategy is the constructing algebraic equations. However, the most successful strategy is the trial and error. (3)Most likely error patterns are the use of inadequate formulas and wrong trial and errors. Based on these results, a teaching program with various schema is developed and shown to be effective for mid level students in classroom.