• 산업경영시스템학회지
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• 제36권3호
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• pp.142-149
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• 2013

Among ammunitions which are stored in a war field, the lifespan of propelling gunpowder is affected by storage environment such as storage temperature, humidity, and exposure to sunlight. These are because Nitrocellulose (NC) which is the main component of propelling gunpowder can be naturally disassembled to unstable substances similar with other nitric acid ester. We can't prevent it fundamentally from being disassembled, but to restrain induction of automatic disassembly by decomposition product, a decomposition product ($NO_2$, $NO_3$, and $HNO_3$) and tranquillizer DPA (Diphenylamine), having high reactivity, are added into a propellant. For this, it will decrease the velocity of tranquillizer which can also affect the velocity of producing the decomposition product of NC, storage temperature or humidity of propelling gunpowder is higher, drop of tranquillizer content is much faster. Therefore, to extend storage lifespan of propelling gunpowder, it is really important to control storage temperature or humidity inside the magazine. Hereupon, according to the manufacture of small scale model magazine and the result of performing experiments and measuring variation of inside temperature (storage temperature), using roof types that have a steel slate structure of magazine among ground magazines, this research shows the differences in details.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.635-636
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• 2015

한전에서는 전력계통과 연계한 대용량 배터리 에너지저장장치(Energy Storage System)에 전력을 저장하였다가 전력계통의 최대 부하 보상, 주파수 조정, 신재생에너지 출력 평준화 등에 이용하고 있다. 배터리를 이용한 에너지저장장치의 실용성을 확인하기 위하여 한국전력공사 전력연구원 ESS연구사업단에서는 제주시 조천변전소에 4MW급 실증단지를 건설하여 시험을 진행하여 왔다. 최근에는 52MW 배터리 에너지저장장치를 전력계통의 주파수 조정용으로 사업화하고 있으며, 이와 관련된 연구도 진행하고 있다. 한국전력공사 전력연구원에서는 서안성, 신용인 변전소에 건설을 완료하여 시운전 중인 52MW 배터리 에너지저장장치 사업에 관련된 기술개발을 위하여 전력연구원에 24MW용 제어시스템, 조천변전소에 28MW용 제어시스템을 개발하여 관련기술을 서안성, 신용인 변전소 에너지저장장치에 적용하여 자동제어 시운전을 수행하였다. 본 논문에서는 주파수조정용 52MW 배터리 에너지저장장치의 시운전 내용을 소개하고자 한다.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.1125-1131
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• 2014

Application of residential demand response (DR) programs are currently realized up to a limited extent due to customers' difficulty in manually responding to the time-differentiated prices. As a solution, this paper proposes an automatic home load management (HLM) framework to achieve the household minimum payment as well as meet the operational constraints to provide customer's comfort. The projected HLM method controls on/off statuses of responsive appliances and the charging/discharging periods of plug-in hybrid electric vehicle (PHEV) and battery storage at home. This paper also studies the impacts of different time-varying tariffs, i.e., time of use (TOU), real time pricing (RTP), and inclining block rate (IBR), on the home load management (HLM). The study is effectuated in a smart home with electrical appliances, a PHEV, and a storage system. The simulation results are presented to demonstrate the effectiveness of the proposed HLM program. Peak of household load demand along with the customer payment costs are reported as the consequence of applying different pricings models in HLM.

• 전기전자학회논문지
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• 제2권1호
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• pp.34-41
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• 1998

자기 띠 저장 시스템에서 데이터를 저장하고 복원할 수 있는 칩을 구현하였다. 구현된 칩은 아날로그 회로와 디지털 회로가 한 칩안에 같이 내장되어 있으며 F/2F 인코딩과 디코딩을 동시에 지원한다. 아날로그 부분은 초단 앰프, 첨두치 검출기, 비교기, 기준전압 생성회로 등으로 구현 되었으며 디지탈 회로 부분은 기준 윈도우 신호 발생부, F/2F 신호 길이를 측정하는 up/down 계수부, 비트 에러 검출부 및 기타 제어(control) 회로 등을 포함한다. 검출되는 신호특성을 파악하여 아날로그 회로부 설계를 최적화 함으로써 기존의 시스템에서 흔히 쓰이는 AGC(automatic gain control) 회로를 제거하였다. 또 일정한 비트의 길이를 초과한 파손 비트 또는 다분할로 파손된 비트 등을 감지한 경우 신속하게 기준 비트를 재 설정함으로서 데이터의 오인식을 없애주는 회로를 제안하였다. 제안된 회로는 $0.8{\mu}m$ CMOS N-well 일반 공정을 이용하여 구현 되었으며 3.3 V에서 부터 7.5 V의 공급 전압 범위에서 동작하도록 설계 되었다. 5 V의 전원 공급시 약 8 mW의 소모 전력을 보여 주고 있으며 칩 면적은 패드를 포함하여 $3.04mm^2(1.6mm{\times}1.9mm)$이다.

• 한국농공학회논문집
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• 제63권1호
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• pp.27-35
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• 2021

KRC (Korea Rural Community Corporation) is in charge of about 3,400 agricultural reservoirs out of 17,240 agricultural reservoirs, and automatic water level gauges in reservoirs and canals were installed to collect reservoir and canal water level data from 2010. In this study, 10-minute water level data of 173 reservoir irrigation canals from 2016 to 2018 are collected, and discharge during irrigation season was calculated using rating curves. For estimation of water supply, irrigation water requirement was calculated with HOMWRS (Hydrological Operation Model for Water Resources System), and the summation of reservoir water storage decrease was calculated with daily reservoir storage data from RAWRIS (Rural Agricultural Water Resource Information System). From the results, the total yearly amount of irrigation water supply showed less than 10% difference than the irrigation water requirement. The regional analysis revealed that reservoirs in Jeollanam-do and Chungcheongnam-do supply greater irrigation water than average. On the contrary, reservoirs in Gyeongsangnam-do and Chungcheongbuk-do supply less than others. This study was conducted with a limited number of reservoirs compared to total agricultural reservoirs. Nevertheless, it can indicate irrigation water supply from agricultural reservoirs to provide information about agricultural water use for irrigation.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.146-148
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• 2005

According as the industry develops recently, the import and export freight amount is increasing sharply, but physical distribution processing equipment ability had achieved conveyance, surge and setup of physical distribution by human's labor ability. But, inefficiency is indicated in operation of harbor and bay warehouse or physical distribution storage equipment because is ceilinged the processing physical distribution amount and the efficiency in physical distribution processing by these labor ability. Treatise that meet on the request proposes soldier warehouse physical distribution processing system that apply Vision System.

• ALGAE
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• 제37권2호
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• pp.149-161
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• 2022

Noctiluca scintillans is a heterotrophic dinoflagellate that causes red-colored oceans during the day (red tides) and glowing oceans at night (bioluminescence). This species feeds on diverse prey, including phytoplankton, heterotrophic protists, and eggs of metazoans. Thus, many scientists have conducted studies on the ecophysiology of this species. It is easy to cultivate N. scintillans at a scale of <1 L, but it is difficult to cultivate them at a scale of >100 L because N. scintillans cells usually stay near the surface, while prey cells stay below the surface in large water tanks. To obtain mass-cultured N. scintillans cells, we developed an automatic system for cultivating N. scintillans on a scale of 100 L. The system consisted of four tanks containing fresh nutrients, the chlorophyte Dunaliella salina as prey, N. scintillans for growth, and N. scintillans for storage, respectively. The light intensities supporting the high growth rates of D. salina and N. scintillans were 300 and 20 µmol photons m^-2 s^-1, respectively. Twenty liters of D. salina culture from the prey culture tank were transferred to the predator culture tank, and subsequently 20 L of nutrients from the nutrient tank were transferred to the prey culture tank every 2 d. When the volume of N. scintillans in the predator culture tank reached 90 L 6 d later, 70 L of the culture were transferred to the predator storage tank. To prevent N. scintillans cells from being separated from D. salina cells in the predator culture tank, the culture was mixed using an air pump, a sparger, and a stirrer. The highest abundance of N. scintillans in the predator culture tank was 45 cells mL^-1, which was more than twice the highest abundance when this dinoflagellate was cultivated manually. This automatic system supplies 100 L of N. scintillans pure culture with a high density every 10 d for diverse experiments on N. scintillans.

• 대한교통학회지
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• 제32권5호
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• pp.452-461
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• 2014

기존 주차조사는 광범위한 조사지역을 대상으로 조사원이 직접 주차차량의 번호판을 확인하는 방식으로 기동성의 저하, 조사와 입력의 이원화로 인한 입력오류, 많은 조사시간과 비용이 소요되는 단점을 가지고 있었다. 따라서 본 연구에서는 기존 조사원에 의한 주차조사의 단점을 극복하기 위해 최근 상용화된 고성능 영상분석장비, 위성측량장비, 적외선 조명 등을 이용하여 자동주차조사를 위한 방법에 관한 연구를 수행하였으며 본 연구결과 개발된 자동주차조사 방법을 이용하여 조사된 데이터를 수정, 저장, 분석 및 출력이 가능한 주차분석 소프트웨어를 개발하였다. 장비를 이용한 자동주차조사 시 조사차량의 주행속도, 영상분석장비의 촬영각도, 주차차량 상호간 차간간격, 조사차량과 주차차량의 이격거리 등에 의해 조사의 정밀도가 영향을 받는 것으로 나타나 장비를 이용한 자동주차조사의 정확도를 향상시키기 위해 실험을 통해 각 요소별 최적조합을 도출하였다. 또한 기존 주차조사 데이터가 체계적으로 저장, 관리되지 못하고 있는 문제점을 극복하고 주자정책 수립을 지원하기 위한 주차분석을 지원하기 위한 주차분석 소프트웨어를 개발하였다.

• 한국측량학회지
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• 제12권1호
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• pp.89-94
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• 1994

최근 많은 연구가 실시간 지도제작시스템의 개발에 초점이 맞춰지고 있으며, 일반적으로 자동차나 비행기로부터 지형에 관련된 수치형태의 정보를 얻고 있다. 본 연구는 미국 오하이오 주립대학의 지도 제작센터에서 개발한 일명 "GPS-Van"이라고 하는 관측장비를 이용하여 얻어진 수치영상으로부터 도로정보를 자동추출하고 수치자료의 효과적인 저장과 관리를 위한 방법을 제시하는데 목적을 두고 있다. 도로의 경계선 검출은 수치사진측량기법을 적용하므로써 수치영상에서 자동추출할 수 있으며 실시간 3차원위치 결정도 가능했다. 또한 자료저장단계를 레스터자료단계, 객체지향자료단계, 벡터자료단계로 구성되는 3단계 자료 저장방법과 자료관리 측면에서 효과적인 자료압축과 검색을 위해 사지수형자료구조를 제안하였다.구조를 제안하였다.

• 근관절건강학회지
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• 제30권3호
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• pp.263-272
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• 2023

Purpose: The aim of this study was to provide a scientific basis for shelf life and re-establish the shelf life in a hospital environment by investigating the validity periods of various packaging materials. Methods: We selected six departments to store sterilized items, prepared 482 sterilized items, and stored them for 12 months. Each sample was tested using a microbiological culture in the laboratory every two weeks. When the result was positive, the sample was considered contaminated. The temperature and relative humidity were measured using an automatic control system to investigate the storage environment during the study period. Results: Except for two samples, which were positive in the 22nd and 28th weeks, 480 samples were negative. The temperature and relative humidity of the sample storage area were measured every week. The annual average temperature was 23.6±1.6℃, and the mean relative humidity was 35.1±15.2%. The cabinets used in this study were the two-open and four-closed types. Conclusion: This study confirmed the validity of the expiration date in a hospital environment. Based on the results, the nonwoven fabric remained sterile for more than nine months. No case of contamination of the paper-plastic pouch packaging was observed, owing to the microbial culture for two months.