• 전자공학회논문지A
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• 제30A권4호
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• pp.11-19
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• 1993

The complex permittivity and the linewidth of microwave ferrites are measured using the well known cavity perturbation method. The cavity perturbation method has been widely used for the measurement of complex permittivity and conductivity of low loss magnetic and dielectric materials at microwave frequencies. TT1-2000, TT73-2200, and G-113 samples ordered from Trans-Tech Inc, are tested. TE$_{103}$ and TE$_{106}$ rectangular waveguide cavities are fabricated and the ferrite sample of cylidrical rod and sphere shapes are prepared. The error between the measurement values and the supplier's data is less than 1 percent in case of $\varepsilon$’ and about 10 percent in case of linewidth ($\Delta$H). Worst case error analysis shows that our measured results are well within the error bound calculated from the accuracy specification of the measuring instruments.

• 한방재활의학과학회지
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• 제28권4호
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• pp.125-130
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• 2018

This case report was conducted to introduce the use of miniscalpel-acupuncture for the treatment of hand osteoarthritis. A-76-year old female patient who had pain on both hands due to osteoarthritis was treated with miniscalpel-acupuncture for 7 weeks. The main outcome were the Numeral Rating Scale (NRS) and the grip strength by dynamometer. After miniscalpel-acupuncture treatment, NRS was decreased and the strength of grasp was increased. The result of this study suggests that the treatment of miniscalpel-acupuncture may be effectively used to decrease pain and increase grip strength of patients who suffer from hand osteoarthritis. Further research is necessary by the reason of the limited sample size of this study.

• 대한원격탐사학회지
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• 제19권3호
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• pp.201-208
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• 2003

Much effort has been made in the radiometric calibration of the ocean scanning multispectral imager (OSMI) since after the successful launch of KOMPSAT-1 in 1999. A series of calibration coefficients for OSMI detectors were obtained in collaboration with the NASA Sensor Intercomparison and Merger for Biological and Interdisciplinary (SIMBIOS) project office. In this study, we ompare the OSMI level-2 products (e.g., chorophyll-a concentration) calculated from the NASA cross-calibration coefficients with the SeaWiFS counterparts. Sample study areas are some of diagonostic data sites recommended by the SIMBIOS working group. Results of this study show that the OSMl-derived chlorophyll-a concentration agrees well with the SeaWiFS counterpart in Case 1 water; however, differences become larger in Case 2 water.

• 한국산학기술학회논문지
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• 제16권12호
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• pp.8165-8175
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• 2015

여름철이 무더운 대한민국에서는 냉방에 많은 전력을 소비한다. 이 경우 간접증발냉각을 동시에 적용하면 전기 사용을 줄일 수 있다. 본 연구에서는 알루미늄, 플라스틱, 플라스틱/종이 재질로 만들어진 간접증발소자에 대하여 건표면 및 습표면 실험을 수행하였다. 실험 결과 플라스틱/종이 소자의 간접증발효율은 38.5% ~ 51.4%로 알루미늄 소자의 값 (41.9% ~ 47.5%)과 유사하고 플라스틱 소자의 값 (29.0% ~ 37.4%)보다는 높게 나타났다. 이로부터 저가의 플라스틱/종이 재질의 간접증발소자가 고가의 알루미늄 재질 간접증발소자를 대체할 수 있으리라 판단된다. 하지만 종이 채널의 압력손실은 알루미늄 채널의 압력손실보다 92% ~ 106% 크다. 한편 종이와 알루미늄 건채널의 열전달계수는 플라스틱 건채널의 값보다 15% ~ 44%, 185% ~ 203% 크게 나타났다. 반면 종이 건채널의 압력손실은 알루미늄 건채널 보다 93% ~ 106%, 플라스틱 건채널보다 34% ~ 48% 크게 나타났다. 습표면 해석결과 알루미늄 습채널에서는 17% ~ 23%, 플라스틱 습채널에서는 30% ~ 37%가 건표면으로 나타났다. 반면 종이 습채널의 경우는 100% 습표면으로 나타났다. 이는 종이의 흡습성이 알루미늄이나 플라스틱보다 월등하기 때문이다.

• 한국미생물·생명공학회지
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• 제44권3호
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• pp.278-284
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• 2016

기능성으로 각광 받는 블루베리, 아로니아, 귀리, 단호박, 생강의 국내외 중간소재를 구입하여 기능성 성분을 비교, 분석하였다. 시판 중간소재 80% 메탄올 추출물의 Total phenolics contents (TPC), total anthocyanins contents (TAC), total flavonoids contents (TFC)를 측정하였고, ABTS radical 소거능, DPPH radical 소거능을 통해 항산화능을 측정 후, 통계적 유의성을 분석하였다. TPC (mg gallic acid equivalent/100 g dried sample)와 TFC (mg catechin equivalent/ 100 g dried sample)의 경우, 모두 국내산 블루베리(TPC, 2,917 ± 200; TFC, 1,327 ± 31)와 단호박(TPC, 476 ± 20, TFC, 23 ± 2)이 국외산 보다 높았고, 국외산은 아로니아, 귀리, 생강의 중간소재가 더 높았다. TAC (mg cyaniding-3-glucoside/100 g dried sample)는 국내산 블루베리(949 ± 57), 국외산 아로니아(2,032 ± 153)가 각각 높았다. 항산화능(mg vitamin C equivalent/100 g dried sample)은 ABTS radical 소거능의 경우, 국내산 블루베리(7,050 ± 321), 단호박(311 ± 8), 생강(3,322 ± 109)이 국외산보다 높았고, DPPH radical 소거능의 경우, 국외산 아로니아(12,667 ± 437), 생강(2,067 ± 99) 중간소재가 국내산보다 높게 나왔다. 이와 같이 국외산 중간소재와의 비교를 통해 국내산 농산물을 이용한 중간소재의 기능성 성분에 관한 기초자료를 제공하고, 새로운 기능성 중간소재 개발에 활용할 수 있을 것이다.

• The Korean Journal of Ceramics
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• 제3권2호
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• pp.116-123
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• 1997

A chemically stabilized $\beta$-cristobalite, which is stabilized by stuffing cations of $Ca^{2+}$ and $Al^{3+}$, was prepared by a solution-polymerization route employing Pechini resin or PVA solution as a polymeric carrier. The polymeric carrier affected the crystallization temperature, morphology of calicined powder, and particle size distribution. In case of the polyvinyl alcohol (PVA) solution process, a fine $\beta$-cristobalite powder with a narrow particle size distribution (average particle size : 0.3$\mu\textrm{m}$) and a BET specific surface area of 72 $\m^2$/g was prepared by an attrition-milling for 1 h after calcination at 110$0^{\circ}C$ for 1h. Wider particle size distribution and higher specific surface area were observed for the $\beta$-cristobalite powder derived from Pechini resin. The cubie(P1-to-tetraganalb) phase transformation in polynystalline $\beta$-cristobalite was induced at approximately 18$0^{\circ}C$. Like other materials showing transformation toughening, a critical size effect controlled the $\beta$-to-$\alpha$ transformation. Densifed cristobalite sample had some cracks in its internal texture after annealing. The cracks, occurred spontaneoulsy on cooling, were observed in the sample with an average grain sizes of 4.0 $\mu\textrm{m}$ or above. In case of the sintered cristobalite having a composition of CaO.$2Al_2O_3$.40SiO$_2$, small amount of amorphous phase and slow grain growth during annealing were observed. Shear stress-induced transformation was also observed in ground specimen. Cristobalite having a composition of CaO.2Al2O3.80SiO2 showed a more sensitive response to shear stress than the CaO.$2Al_2O_3$.40SiO$_2$ type cristobalite. Shear-induced transformation resulted in an increase of volume about 13% in $\alpha$-cristobalite phase on annealing for above 10 h in the case of the former composition.

• 한국자동차공학회논문집
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• 제20권3호
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• pp.133-140
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• 2012

In this study, 3 kinds of models about bike frame are simulated with static structural analysis, And fatigue life, damage and durability according to fatigue load are analyzed. A bike frame model with diamond type is compared with another model on the reinforced support with its type. In case of the reinforced support type, maximum equivalent stress or total deformation is shown with 10% or 20% more than the diamond type respectively. At both types of models, the trends of fatigue life and damage at both types are same. 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable among the cases of nonuniform fatigue loads. In case of 'Sample history' with the average stress of 0 to -1MPa and the amplitude stress of 0 to 1MPa, the possibility of maximum damage becomes 3%. This stress state can be shown with 6 times more than the damage possibility of 'SAE Bracket history' or 'SAE transmission'. In case of the reinforced support type, fatigue life becomes shorter and damage probability becomes larger at the right side installed with support than diamond type. The structural result of this study can be effectively utilized with the design on bike frame by investigating prevention and durability against its damage.

• 대한예방한의학회지
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• 제24권1호
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• pp.27-35
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• 2020

Objectives : The purpose of study was estimation of adverse events [AEs] scale relating herbal medicine in Korea using Korean Medicine Utilization and Herbal Medicine Consumption Survey (National statistics No. 117087). Methods : Using microdata of Korean Medicine Utilization and Herbal Medicine Consumption Survey 2017, the number of inpatients and outpatients who experienced AEs was calculated. The microdata included AEs of all treatment methods that have been performed by visiting Korean medical institutions for one year, so set up the data into three models; model A (in case all treatments were only herbal medicine for one year), model B (in case herbal medicines were a part of all treatment methods in 1 year), model C (in case herbal medicines were a part of treatment methods at least one time in 1 year). The proportion of patients who experienced AEs during the last 1 year was calculated and then, the number of AEs relating herbal medicine was estimated. Results : A total of 1,010 outpatients and 904 inpatients were included in Korean Medicine Utilization and Herbal Medicine Consumption Survey 2017. The number of patients who had experienced AEs in the past 1 year was 0 in the model A, 9 in the model B (5 for outpatients, 4 for inpatients), and 19 in the model C (10 for outpatients, 9 for inpatients). By consideration for the complex sample survey, estimating the number of AEs relating herbal medicine, the model A was 0, the model B was 36,457 patients (0 to 75,526 patients), and the model C was 84,830 patients (26,314 to 143,347 patients). Conclusion : From the results of this study, it was possible to estimate the scale of AEs relating herbal medicines in Korea, suggesting that it is necessary to understand the actual condition of AEs and establish its management system.

• 한국지역사회생활과학회지
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• 제23권2호
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• pp.103-116
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• 2012

The purpose of this study was to investigate the trend of academic journals of institutional foodservice published from 2005 to 2009. This study was conducted by content analysis. We collected 322 articles including the subject of institutional foodservice Industry published from January 1, 2005 to December 31, 2009. Classification based on content analysis was conducted based on research method, statistical analysis, survey area, institution and location, sample type and research subject. First, in case of the research method, primary field survey/monitoring showed the highest rate. In addition, statistical analysis was as follows. Frequency/descriptive analysis were used as the highest rate. Survey area was a high percentage in case of Seoul/Incheon/Gyeong-gi province. In case of the institution and location, school/university showed the highest rate. In the sample type, foodservice employee/dietitian/nutrition teacher showed the highest rate. In this study, the most important research subjects were classified study subjects into seven by taking advantage of the previous studies. The greatest numerical study in seven study subjects was 'service quality and customers'(28.9%), and the following subjects were 'foodservice operation'(26.4%), 'hygiene, security and microbiology' (15.8%), 'organization and human resource' (15.5%). But it is noteworthy that 'marketing and strategic management'(9.6%) and 'education and training'(3.1%) of lower research results in this study are also important fields in institutional foodservice industry. Moreover, the study of such subjects is considered more necessary in the future.

• 가족자원경영과 정책
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• 제16권4호
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• pp.45-68
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• 2012

This study performed an analysis to determine if an individual can maintain the current consumption, in the case of a single retired elderly person's household using the accumulated assets. Assets are divided into three types, based on the behavioral economics life cycle hypothesis : financial assets, real assets excepting residential assets, and residential assets, and it is assumed that these assets were used on a step-by-step basis. Also, if the assets were sufficient, the maximum withdrawal amount was calculated. The results of the analysis are as follows. First, the monetary assets were sufficient to cover the cost of living for 2.7 years, 6.4 years by using the real assets of the non-occupied housing, and 26.3 years in the case of residential property. Second, in the case of preferentially using the financial assets, 4.4% of the sample households were able to cover the cost of living. Households that were not able to cover the cost of living used the next-stage assets, real assets of the non-occupied housing. Households that were not able to cover the cost of living by financial assets liquidated the real assets with the exception of residential assets and used these to cover the cost of living. A total of 4.8% of the households were able to maintain the current cost of living through the second stage and 25.5% supplemented their funds by using residential assets. That is to say, 35% of the sample households were able to maintain the current level of living by using their assets.