• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.480-487
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• 2012

The application of solar energy in residential building is general and natural in today. And application methods of solar thermal energy is divided in two kind of form, single evacuated tube and flat-plate form. Then in this study, the efficiency of single evacuated tube and flat-plate system is compared by total and effective area considering the time receiving the solar radiation between 24 hours and the specific time(10:00~15:00). As a result of the experiment, single evacuated tube and flat-plate collector's efficiency is varied by the quantity of solar radiation. And especially, the flat-plate system is more affected by outdoor temperature. Therefore the application of solar thermal system should be considered the solar radiation and outdoor temperature.

• 한국광학회지
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• 제5권2호
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• pp.333-339
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• 1994

단일모드 광섬유를 부착한 고속 광통신용 PIN-전치증폭기 모듈을 GaInAs PIN 광검출기와 GaAs 전치증폭기를 하이브리드로 집적하여 제작하였다. PIN 광검출기의 정전용량은 0.35pF이었으며 이 소자의 수광직경은 $20{\mu}m$였다. 제작된 수광모듈의 -3dB 차단주파수는 2GHz 이상이었으며 2.5Gbps NRZ$(PRBS=2^{23}-1)$ 입력광신호에 대해 비트오율이 $10^{-9}$일 때 -25.2dBm의 수신감도를 보였다.

• 조명전기설비학회논문지
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• 제26권7호
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• pp.16-22
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• 2012

With the increase of consumption of new renewable energy, the use of Electric Double Layer Capacitor(EDLC) is being gradually widened as the next generation energy storage device. In order to expand the market of EDLC which is recently receiving a lot of attraction as a new promising area, development of a charge/discharge cycle tester to measure and test performance, is essential. Therefore, this research designed a circuit to measure capacity and internal resistance and a circuit to measure voltage maintenance properties, based on EDLC's basic charging/discharging properties so it is able to measure the state of charge and discharge at high speed. When evaluating performance characteristics, the 5[V]/100[A] prototype-EDLC charge/discharge testing system developed for this research showed ${\pm}0.1$[%] of accuracy of voltage and current measurement. It was also proved that the developed charge/discharge testing system for EDLC can be applied to the actual industry, when testing the entire system using a program produced for data monitoring and acquisition.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권1호
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• pp.9-14
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• 2011

Recently, the population of patients who refuse transfusion has increased for both religious and non-religious reasons, even in life threatening emergency situations. Their refusal has highlighted the need to develop nonblood transfusion surgery techniques to decrease the risk from blood transfusions. A 57-year woman with an ulcerative lesion on the gingiva of the right upper molar area visited the department of oral and maxillofacial surgery in Dankook University Dental Hospital. After a preliminary evaluation, the patient was diagnosed with squamous cell carcinoma. As she refused blood transfusion during surgery for religious reasons, surgery was planned using recombinant human erythropoietin (rHuEPO) without a blood transfusion. The patient underwent a partial maxillectomy, supraomohyoid neck dissection, free radial forearm flap and split thickness skin graft under general anesthesia. rHuEPO and iron were used before and after surgery. The hemoglobin/hematocrit (Hb/Hct) level, iron (Fe) and total iron-binding capacity (TIBC) were assessed. The patient recovered completely without any blood transfusions. rHuEPO is a viable alternative for patients with religious objections to receiving blood transfusions.

• 한국통신학회논문지
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• 제12권6호
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• pp.621-633
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• 1987

본 논문에서는 Token ring방식 Star-wired ring형 근거리 통신망을 구성하기 위한 in board방식의 망 접속 장치와 집중기를 마이크로프로세서로서 구현하였다. 집중기에 통신 제어 기능을 갖도록 하여 고장난 망 접속 장치를 우회 통과시켜 통신이 중단되지 않도록 하며, 데이터 패키트 전송시에는 집중기가 송신 및 수신측의 망 접속 장치를 인식하여 단일망을 구성하여 송신및 수신측 사이의 망 접속 장치에서의 통과 지연을 줄임으로써 고부하 및 저부하시에도 높은 througuput을 유지할 수가 있었다. 또한, 구성된 시스템에 대한 성능 평가를 실시하였다.

• Journal of Information Display
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• 제8권4호
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• pp.27-31
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• 2007

In this paper, we present an efficient tiled stereo display system for tangible meeting. For tangible meeting, it is important to provide immersive display with high resolution image to cover up the field of view and provide to the local user the same environment as that of remote site. To achieve these, a high resolution image needs to be transmitted for reconstruction of remote world, and it should be displayed using a tiled display. However, it is hard to transmit high resolution image in real time due to the limit of network bandwidth, and so we receive multiple images and reconstruct a remote world with received images in advance. Then, we update only a specific area where remote user exists by receiving low resolution image in realtime. We synthesize the transmitted image to the existing environmental map of remote world and display it as a stereo image. For this, we developed a new system which supports GPU based real time warping and blending, automatic feature extraction using machine vision technique.

• The Journal of Asian Finance, Economics and Business
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• 제7권7호
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• pp.169-178
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• 2020

This study examines the current situation of responsibility accounting and proposed management solutions according to responsibility centers on public universities in Vietnam. The study applies quantitative research methods, and collected data through structured questionnaires to 138 public universities in Vietnam in 2019, receiving back 55 valid questionnaires. The data was cleaned and analyzed with SPSS software. The results show that most public universities in Vietnam assigned management responsibility to their departments, but responsibility accounting was not comprehensive since many universities are not financially autonomous. The Kruskal Wallis Test was conducted to compare the current situation of responsibility accounting among universities by the degree of autonomy and by geographic area. The research found out that totally autonomous universities assigned management responsibility to responsibility centers better than semi-autonomous and non-autonomous universities did. Regarding the evaluation of management responsibility, universities in Central Vietnam rated specific quantitative criteria, residual income (RI) and returns on investment (ROI) higher than universities in the North and the South of Vietnam did. However, universities in the South of Vietnam rated the evaluation of profits by department higher than the rest. The study also suggests structure for establishing responsibility centers in accordance with public universities in Vietnam.

• 한국통신학회논문지
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• 제18권2호
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• pp.184-191
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• 1993

최근 MOS 공정기술로 집적화된 연속시간 필터 연구가 주목을 받고 있다. 본 논문에서는 차단주파수 3,400Hz를 갖는 연속시간 5차 타원 저역통과 MOSFET-C 필터를 실현하기 위하여, 먼저 각 블록을 동조할 수 있는 종속연결법으로 능동 RC 필터를 설계하였다. 그리고 능동 RC 회로의 저항들을 triode 영역에서 작동하는 NMOS depletion mode 트랜지스터 선형저항으로 실현하였다. 이러한 연속시간 MOSFET-C 필터는 스윗치드 커패시터 필터에 비하여 구조가 간단하여 칩의 면적을 줄일 수 있다. 설계된 MOSFET-C 필터 특성을 PSPICE 프로그램으로 시뮬레이션 하였다.

• 한국물환경학회지
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• 제28권6호
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• pp.819-832
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• 2012

HSPF model based on BASINS was applied for the Hwaseong Reservoir watershed (HRW) to evaluate the feasibility of water quality management. The watershed was divided into 45 sub-basins considering various watershed environment. Streamflow was calibrated based on the measured meteorological data, discharge data of treatment plants and observed streamflow data for 2010 year. Then the model was calibrated against the field measurements of water qualities, including BOD, T-N and T-P. In most cases, there were reasonable agreements between observed and predicted data. The validated model was used to analyze the characterization of pollutant load from study area. As a result, Non-point source pollutant loads during the rainy season was about 66~78% of total loads. In rainy-season, water quality parameters depended on precipitation and pollutant loads patterns, but their concentration were not necessarily high during the rainy season, and showed a decreasing trend with increasing water flow. As another result of evaluation for load duration curves, in order to improve water qualities to the satisfactory level, the watershed managements considering both time-variant and pollution sources must be required in the HRW. Overall, it was found that the model could be used conveniently to assess watershed characteristics and pollutant loads in watershed scale.

• 한국농공학회논문집
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• 제46권2호
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• pp.107-114
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• 2004

NPS pollutant loads from sandy clayey and clayey loam runoff plots were measured. Runoff plots were 2$\times$10 m in size and 8~10% in slope and paddy area was 4,620 $m^2$. Soybean, corn, tobacco and control (natural weed) were cultured. Precipitation during the growing season of June to October, 2002 was 869.5 mm. Runoff and water quality were measured more than 10 times during the measurements depending on the growing stage. Pollutants loads were estimated by using respective concentration and runoff volume. Runoff occurred when daily rainfall exceeded about 30 mm. The largest runoff was observed from the paddy but pollutant loads were larger from upland crops than those from paddy. SS loads from paddy and upland were 1.4 ton/ha/yr and 3.1~4.3 ton/ha/yr, respectively. COD loads 30 kg/ha/yr and 66~90 kg/ha/yr, T-N loads 13 kg/ha/yr and 14~23 kg/ha/yr, T-P loads 1 kg/ha/yr와 4 kg/ha/yr, nitrate nitrogen loads 1 kg/ha/yr and 4~8 kg/ha/yr, and phosphate phosphorus loads 0 kg/ha/yr and 4~6 kg/ha/yr, respectively. It was concluded that NPS pollutant loads from upland crop culture have greater impact on the quality of the receiving water body than those from paddy culture.