• Journal of the Korean Magnetics Society
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• v.17 no.4
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• pp.166-171
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• 2007

We report the magneto-transport properties of an individual single crystalline Bi nanowire grown by a spontaneous growth method. We have successfully fabricated a four-terminal device based on an individual 400-nm-diameter nanowire using plasma etching technique to remove an oxide layer forming on the outer surface of the nanowire. The transverse MR (2496% at 110 K) and longitudinal MR ratios (38% at 2 K) for the Bi nanowire were found to be the largest known values in Bi nanowires. This result demonstrates that the Bi nanowires grown by the spontaneous growth method are the highest-quality single crystalline in the literatures ever reported. We find that temperature dependence of Fermi energy ($E_F$) and band overlap (${\triangle}_0$) leads to the imbalance between electron concentration ($n_e$) and hole concentration ($n_h$) in the Bi nanowire, which is good agreement with the calculated $n_e\;and\;n_h$ from the respective density of states, N(E), for electrons and holes. We also find that the imbalance of $n_e\;and\;n_h$ plays a crucial role in determining magnetoresistance (MR) at T<75 K for $R_T$ and at T<205 K for $R_L$, while mean-free path is responsible for MR at T>75 K for $R_T$ and T>205 K for $R_L$.

• Proceedings of the Korea Database Society Conference
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• 1998.09a
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• pp.293-312
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• 1998

$\square$ 정보화 혁명의 대국민 인식수단과 초고속정보통신망의 주요 응용 서비스로서 부각 $\square$ 전통적인 정보이용방법에 대한 이용자들의 인식의 변화로 도서관 활성화 방안으로써 정보통신기술의 도입 $\square$ 선진 각국의 전자도서관 구축의 국가적 추진 $\square$ 국내 초고속정보통신망의 구축과 보급 확대 $\square$ 모든 국민이 지역, 시간의 제약없이 도서관에 접근하여 필요한 자료를 획득 $\square$ 정보획득시간 단축으로 국내연구자들의 연구력 증진 $\square$ 정보화의 지역격차 해소 $\square$ 국내 도서관의 전자도서관 사업 촉진 $\square$ 주요 전자도서관의 통합연동체제를 마련 $\square$ 주요 도서관별 대상분야 조정으로 중복투자 방지 $\square$ 초고속정보통신망의 주요한 응용서비스로 가시화 - 초고속정보통신망의 선도적 대국민 가시화 - 이에 따른 민간부문의 참여 및 투자 촉진 $\square$ 국가, 산업, 국민생활 정보화의 주요한 기반 구축 $\square$ 지역적 정보불균형 해소 - 일부지역에 편중되어 있는 정보를 인터넷을 이용하여 시.공간 제약없이 제공함으로써 정보의 불균형 해소 $\square$ 전자도서관의 기본모델 제시 -전자도서관의 주요기능인 타기관간 자료연동 및 검색시스템을 구현함으로써 향후 구축되는 전자도서관의 기본모델 제시 $\square$ 전자도서관간 자료공유체제 구축 -시범사업 참여도서관간 분산 관리하고 있는 정보의 공유를 위한 표준체제 구축(중략) 것으로 나타났다.까지 증가율을 보여 주었다. 것으로 나타났다.대표하는 압밀계수의 추정이 가능할 것으로 사료된다. $O_3$/라는 결정학적 관계를 가지며 에피탁샬 성장했음을 알 수 있었다.있었다.다(p<0.05)..8800-0.6800로 각각 표시되었다.~$\pm$10 V의 측정범위에서 memory window가 계속 증가하는 것을 보여주었다./$^{\circ}C$의 고주파 유전특성을 얻었다. 얻었다.끼쳤다.보였다.다. 싸이클링 성능을 보였다.다.보였다.다.고 입력 반사손실을 그림 I, 2, 3에 각각 나타내었다. 대책을 요구하고 있다.하는 경향을 보였다. 생존율은 48시간째부터 폐사하기 시작하여 144시간째에는 전량폐사하였다. 삼투압 조절 능력을 위한 여러가지 파라메타에서 15 $\textperthousand$구는 이상이 없는 것으로 추측되나, 0 $\textperthousand$구에서는 코티졸, Na$^{+}$, K$^{+}$, Cl￣, 총단백질 및 AST에서 시간경과에 따른 삼투압 조절 능력에 문제가 있는 것으로 보여진다.c}C$에서 5시간 가열조리 후 잔존율은 각각 84.7% 및 73.3%였고, 질소가스 통기하에서는 잔존율이 88.9% 및 81.8%로 더욱 안정하였다.8% 및 12.44%, 201일 이상의 경우 13.17% 및 11.30%로 201일 이상의 유기의 경우에만 대조구와 삭제 구간에 유의적인(p<0.05) 차이를 나타내었다.는 담수(淡水)에서 10%o의 해수(海水)로 이주된지 14일(日) 이후에 신장(腎臟)에서 수축된 것으로 나타났다. 30%o의 해수(海水)에 적응(適應)된 틸라피아의 평균 신사구체(腎絲球體)의 면적은 담수(淡水)에 적응된 개체의 면적보다 유의성

• Microbiology and Biotechnology Letters
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• v.50 no.1
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• pp.135-146
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• 2022

Obesity is closely associated with profound dyslipidemia, insulin resistance, and fatty liver disease. Recent reports have suggested that alterations in gut microbiota can be linked to diet-induced obesity. In this study, the anti-obesity effects of Weissella confusa WIKIM51 isolated from kimchi were investigated, as evidenced by: i) reduced lipid accumulation and downregulated adipogenesis-related genes in 3T3-L1 adipocytes; ii) suppressed gains in body weight and epididymal fat mass; iii) reduced serum lipid levels, for example, triglyceride and total cholesterol; iv) increased serum adiponectin levels and reduced serum leptin levels; v) downregulated lipogenesis and upregulated β-oxidation-related genes in the epididymal fat; and vi) altered microbial communities. The collective evidence indicate the potential value of W. confusa WIKIM51 as a functional food supplement for the prevention and amelioration of obesity.

• Korean Journal of Remote Sensing
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• v.38 no.5_3
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• pp.913-924
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• 2022

In this paper, we presented a database construction of undersea images for the Habitats of Ecklonia cava and Sargassum and conducted an experiment for semantic segmentation using state-of-the-art (SOTA) models such as High Resolution Network-Object Contextual Representation (HRNet-OCR) and Shifted Windows-L (Swin-L). The result showed that our segmentation models were superior to the existing experiments in terms of the 29% increased mean intersection over union (mIOU). Swin-L model produced better performance for every class. In particular, the information of the Ecklonia cava class that had small data were also appropriately extracted by Swin-L model. Target objects and the backgrounds were well distinguished owing to the Transformer backbone better than the legacy models. A bigger database under construction will ensure more accuracy improvement and can be utilized as deep learning database for undersea images.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.344-390
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• 1977

The purpose of this paper was to schedule optimum cutting strategy which could maximize the total yield under certain restrictions on periodic timber removals and harvest areas from an industrial forest, based on a linear programming technique. Sensitivity of the regulation model to variations in restrictions has also been analyzed to get information on the changes of total yield in the planning period. The regulation procedure has been made on the experimental forest of the Agricultural College of Seoul National University. The forest is composed of 219 cutting units, and characterized by younger age group which is very common in Korea. The planning period is devided into 10 cutting periods of five years each, and cutting is permissible only on the stands of age groups 5-9. It is also assumed in the study that the subsequent forests are established immediately after cutting existing forests, non-stocked forest lands are planted in first cutting period, and established forests are fully stocked until next harvest. All feasible cutting regimes have been defined to each unit depending on their age groups. Total yield (Vi, k) of each regime expected in the planning period has been projected using stand yield tables and forest inventory data, and the regime which gives highest Vi, k has been selected as a optimum cutting regime. After calculating periodic yields and cutting areas, and total yield from the optimum regimes selected without any restrictions, the upper and lower limits of periodic yields(Vj-max, Vj-min) and those of periodic cutting areas (Aj-max, Aj-min) have been decided. The optimum regimes under such restrictions have been selected by linear programming. The results of the study may be summarized as follows:- 1. The fluctuations of periodic harvest yields and areas under cutting regimes selected without restrictions were very great, because of irregular composition of age classes and growing stocks of existing stands. About 68.8 percent of total yield is expected in period 10, while none of yield in periods 6 and 7. 2. After inspection of the above solution, restricted optimum cutting regimes were obtained under the restrictions of Amin=150 ha, Amax=400ha, $Vmin=5,000m^3$ and $Vmax=50,000m^3$, using LP regulation model. As a result, about $50,000m^3$ of stable harvest yield per period and a relatively balanced age group distribution is expected from period 5. In this case, the loss in total yield was about 29 percent of that of unrestricted regimes. 3. Thinning schedule could be easily treated by the model presented in the study, and the thinnings made it possible to select optimum regimes which might be effective for smoothing the wood flows, not to speak of increasing total yield in the planning period. 4. It was known that the stronger the restrictions becomes in the optimum solution the earlier the period comes in which balanced harvest yields and age group distribution can be formed. There was also a tendency in this particular case that the periodic yields were strongly affected by constraints, and the fluctuations of harvest areas depended upon the amount of periodic yields. 5. Because the total yield was decreased at the increasing rate with imposing stronger restrictions, the Joss would be very great where strict sustained yield and normal age group distribution are required in the earlier periods. 6. Total yield under the same restrictions in a period was increased by lowering the felling age and extending the range of cutting age groups. Therefore, it seemed to be advantageous for producing maximum timber yield to adopt wider range of cutting age groups with the lower limit at which the smallest utilization size of timber could be produced. 7. The LP regulation model presented in the study seemed to be useful in the Korean situation from the following point of view: (1) The model can provide forest managers with the solution of where, when, and how much to cut in order to best fulfill the owners objective. (2) Planning is visualized as a continuous process where new strateges are automatically evolved as changes in the forest environment are recognized. (3) The cost (measured as decrease in total yield) of imposing restrictions can be easily evaluated. (4) Thinning schedule can be treated without difficulty. (5) The model can be applied to irregular forests. (6) Traditional regulation methods can be rainforced by the model.

• Radiation Oncology Journal
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• v.22 no.4
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• pp.288-297
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• 2004

Puporse: The aims of this study were to evaluate the change of $[^18F]fluoromisonidazole$($[^18F]FMISO$) uptake in C3H mouse squamous cell carcinoma-VII (SCC-VII) treated with mild hyperthermia ($42^{circ}C$) and nicotinamide and to assess the biodistribution of the markers in normal tissues under similar conditions. Methods and Materials: $[^18F]FMISO$ was producedby our hospital. Female C3H mice with a C3H SCC-VII tumor grown on their extremities were used. Tumors were size matched. Non-anaesthetized, tumor-bearing mice underwent control or mild hyperthermia at $42^{circ}C$ for 60 min with nicotinamide (50 mg/kg i.p. injected) and were examined by gamma counter, autoradiography and animal PET scan 3 hours after tracer i.v. injected with breathing room air, The biodistribution of these agents were obtained at 3 h after $[^18F]FMISO$ injection. Blood, tumor, muscle, heart, lung, liver, kidney, brain, bone, spleen, and intestine were removed, counted for radioactivity and weighed. The tumor and liver were frozen and cut with a cryomicrotome into 10- um sections. The spatial distribution of radioactivity from the tissue sections was determined with digital autoradiography. Results: The mild hyperthermia with nicotinamide treatment had only slight effects on the biodistribution of either marker in normal tissues. We observed that the whole tumor radioactivity uptake ratios were higher in the control mice than in the mild hyperthermia with nicotinamide treated mice for $[^18F]FMISO$ ($1.56{\pm}1.03$ vs. $0.67{\pm}0.30$; p=0.063). In addition, autoradiography and animal PET scan demonstrated that the area and intensity of $[^18F]FMISO$ uptake was significantly decreased. Conclusion: Mild hyperthermla and nicotinamide significantly improved tumor hypoxia using $[^18F]FMISO$ and this uptake reflected tumor hypoxic status.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.2
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• pp.108-121
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• 2009

The suspended particulate matters have been collected on membrane filters and glass fiber filters by an 8-stage cascade impactor for 2 years (Sep. 2005${\sim}$Sep. 2007) in Kyung Hee University-Global Campus located on the border of Yongin and Suwon. The 20 chemical species (Al, Mn, Si, Fe, Cu, Pb, Cr, Ni, V, Cd, Ba, $Na^+$, ${NH_4}^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, ${NO_3}^-$, and ${SO_4}^{2-}$) were analyzed by an ICP-AES and an IC after performing proper pre-treatments of each sample filter. Based on these chemical information, the PMF receptor model was applied to identify the source of ambient size-by-size particulate matters. The receptor modeling is the one of the statistical methods to achieve resonable air pollution management strategies. A total of 10 sources was identified in 9 size-ranges such as long-range transport, secondary aerosol, $NH_{4}NO_{3}$ related source, coal combustion, sea-salt, soil, oil combustion, auto emission, incineration, and biomass burning. Especially, the secondary aerosol source assorted in fine and coarse modes was intensively studied.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.247-249
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• 2005

최근 디지털 TV, DVD 플레이어, 홈시어터와 같은 디지털 A/V 기기들을 통합하여 멀티미디어 컨텐츠를 서비스 받는 홈 네트워크 기술에 대한 관심이 높아지고 있다. 이러한 환경에서 UpnP를 이용한 디지털 기기들의 상태를 모니터링하고, 사용자의 요청과 제어 명령을 전달하여, 멀티미디어 컨텐츠를 서비스 받을 수 있도록 하는 연구는 매우 중요하다. 그러나 UPnP는 TCP/IP 기반의 프로토콜을 사용하기 때문에 사용자 인터랙션에 의한 전송 지연 시간이 발생한다. 그러므로 본 논문에서는 셋탑 박스에 최적화된 UPnP AV 시스템을 구현하고 AV 컨텐츠의 효율적인 재생을 위한 UPnP프레임워크의 재생 기법을 제안한다. UPnP AV 시스템은 미디어 서버가 있고, 미디어 서버에 저장된 비디오/오디오 파일 등을 전송받아 재생하기 위한 셋탑 박스에는 컨트롤 포인트와 UPnP 미디어 렌더러의 통합 모델이 탑재된다. 이러한 기법은 다양한 기기를 제어하고 호환성을 제공하는 UPnP프레임워크가 될 수 있다.

• Journal of Environmental Science International
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• v.23 no.3
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• pp.409-431
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• 2014

In this study, the characteristics in the simulation of high-resolution coastal weather, i.e. sea surface wind (SSW) and significant wave height (SWH), were studied in a southeastern coastal region of Korea using the WRF and SWAN models. This analyses was performed based on the effects of various input factors in the WRF and SWAN model during M-Case (moderate days with average 1.8 m SWH and $8.4ms^{-1}$ SSW) and R-Case (rough days with average 3.4 m SWH and $13.0ms^{-1}$ SSW) according to the strength of SSW and SWH. The effects of topography (TP), land cover (LC), and sea surface temperature (SST) for the simulation of SSW with the WRF model were somewhat high on v-component winds along the coastline and the adjacent sea of a more detailed grid simulation (333 m) during R-Case. The LC effect was apparent in all grid simulations during both cases regardless of the strength of SSW, whereas the TP effect had shown a difference (decrease or increase) of wind speed according to the strength of SSW (M-Case or R-Case). In addition, the effects of monthly mean currents (CR) and deepwater design waves (DW) for the simulation of SWH with the SWAN model predicted good agreement with observed SWH during R-Case compared to the M-Case. For example, the effects of CR and DW contributed to the increase of SWH during R-Case regardless of grid resolution, whereas the differences (decrease or increase) of SWH occurred according to each effect (CR or DW) during M-Case.

• Journal of the Korean Society for Railway
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• v.19 no.3
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• pp.314-323
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• 2016

Overhead line voltage of DC railway traction substations has rising or falling characteristics depending on the acceleration and regenerative braking of the subway train loads. The suppression of this irregular fluctuation of the line voltage gives rise to improved energy efficiency of both the railway substation and the trains. This paper presents parameter estimation schemes using the RC circuit model for an overhead line voltage at a 1500V DC electric railway traction substation. A linear artificial neural network with a back-propagation learning algorithm was trained using the measurement data for an overhead line voltage and four feeder currents. The least square estimation method was configured to implement batch processing of these measurement data. These estimation results have been presented and performance analysis has been achieved through raw data simulation.