• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 심포지엄 논문집 정보 및 제어부문
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• pp.223-224
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• 2008

초초임계압 화력발전 제어계통 설계와 관련하여 보일러 제어시스템의 기본 요건인 제어전략을 구현하기 위해 현재 표준화력 500MW 제어시스템과 제어로직을 기반으로 1000MW급에서 필요로 하는 새로운 구조의 제어에 요구되는 제어전략에 대해 각종 제어 운전 모드의 구성과 각 운전 모드에서의 제어전략을 개발하고 있다. 최신제어시스템에서 중요하게 취급되는 자동 플랜트 제어(Automatic Plant Control, APE)의 각종 제어전략 구성에 중점을 두고 있으며 Unit Master Control, Boiler Master Control, Turbine blaster Control, Throttle Pressure Control, Fuel/Air Master Control, Forced Draft Fan Control, Induced Draft Fan Control, Primary Air Fan, Feed Water Master Control, Super Heater/Reheater Steam Temp Control 등의 제어전략을 논하고, 실제 프로세스 응단특성 파악을 위해 국내 신규발전소를 방문하여 수집한 프로세스 응답시험 결과와 특성을 분석하고 USC에 적용하기위한 보일러 제어전략에 대해 논하고자 한다.

• 한국미생물·생명공학회지
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• 제51권4호
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• pp.538-541
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• 2023

In this study, we present the draft genome of Aureobasidium pullulans strain MHAU2101, which is the first strain to effectively control fire blight caused by Erwinia amylovora in Korea. The genome of strain MHAU2101 was composed of 28,669,322 base pairs, with a C+G content of 50.4%. The assembly comprised 17 contigs and had 99.22% completeness. The results of this study will be a valuable resource for future research on the biocontrol mechanism of A. pullulans strain MHAU2101.

• 한국산업보건학회지
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• 제16권3호
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• pp.290-301
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• 2006

A push pull hood system is frequently applied to control contaminants evaporated from an open surface tank. Efficiency of push pull hood system is affected by various parameters, such as, cross draft, vessel shapes, tank surface area, liquid temperature. A previous work assisted by flow visualization technique qualitatively showed that a strong cross draft blown from the pull hood to push slot could destroy a stable wall-jet on the surface of tank, resulting in the abrupt escape of smoke from the surface. In this study, the tracer gas method was applied to determine the effect of cross-draft on the capture efficiency qualitatively. A new concept of capture efficiency was introduced, that is, linear efficiency. This can be determined by measuring the mass of tracer gas in the duct of pull hood while the linear tracer source is in between push slot and pull hood. By traversing the linear tracer source from the push slot to the pull hood, it can be found where the contaminant is escaped from the tank. Total capture efficiency can be determined by averaging the linear efficiencies. Under the condition of cross-draft velocities of 0, 0.4, 0.75, 1.05 and 1.47m/s, total capture efficiencies were measured as 97.6, 95.4, 94.6, 92.7 and 70.5% respectively. The abrupt reduction of efficiency with cross-draft velocity of 1.47m/s was due to the destruction of tank surface wall-jet by the counter-current cross-draft. The same phenomenon was observed in the previous flow visualization study. As an alternative to overcome this abrupt efficiency drop, the 20% increase of hood flow rates was tested, resulting in 20% efficiency increase.

• 식물병연구
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• 제21권3호
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• pp.222-226
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• 2015

The chitinase-producing bacterial strain C-1 is one of the key chitinase-producing biocontrol agents used for effective bioformulations for biological control. These bioformulations are mixed cultures of various chitinolytic bacteria. However, the precise identification, biocontrol activity, and the underlying mechanisms of the strain C-1 have not been investigated so far. Therefore, we evaluated in planta biocontrol efficacies of C-1 and determined the draft genome sequence of the strain in this study. The bacterial C-1 strain was identified as a novel Serratia sp. by a phylogenic analysis of its 16S rRNA sequence. The Serratia sp. C-1 bacterial cultures showed strong in planta biocontrol efficacies against some major phytopathogenic fungal diseases. The draft genome sequence of Serratia sp. C-1 indicated that the C-1 strain is a novel strain harboring a subset of genes that may be involved in its biocontrol activities.

• Journal of Biosystems Engineering
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• 제15권4호
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• pp.290-297
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• 1990

The purposes of this study were to perform theoretical analysis of an electronic-hydraulic hitch control system for position and draft control of tractor implements and to investigate the performance of the control system through computer simulation. Computer simulation models which could predict the responses of the system to the step and sinusoidal inputs in position and draft controls were developed using the simulation package "TUTSIM". The effects of control mode, hydraulic flow rate, deadband, and proportional constant on control performance of the system were investigated. The simulated results were compard with the experimental ones to verify the simulation models. The simulation models appeared to be a useful means for the analysis and the design of the electronic-hydraulic hitch control system.

• 한국유기농업학회지
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• 제6권2호
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• pp.81-106
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• 1998

This study aims to point out what is the basic idea and principle of weed control in or-ganic farming. The korean organic agriculture gets a point in dispute on weed control, be-cause 1) they do not practice the Basic Standard of IFOAM and FAO/WHO Codex Guidelines(draft), and 2) Korean organic farming is defined quite differently from internationally recognized core aspects for organic agriculture. Organic farming, in Korea, is taken to mean just the replacement of chemical fertilizer by organic manure and a-voidance of agricultural chemicals without practicing on rotation, cropping system and so on. As a consequence, organic farmers in Korea are suffering from hard labor to control the weed. In the paper it is discussed on organical weed control method which are required in the Basic Standard of IFOAM and guidelined in the Organic Production Principles of FAO/WHO Codex draft, and furthermore the single or combination effect of those method are also discussed. In conclusion it is suggest the necessity, purpose, and effect of the introduction of the basic stan-dard to korean organic agriculture including organical weed control.

• 한국컴퓨터정보학회논문지
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• 제18권4호
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• pp.113-121
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• 2013

본 논문에서는 사각형 개수로에서 수차 흘수 변화에 따른 회전 효율 파악을 위한 시뮬레이션을 수행하였다. 수차를 이용한 개수로 초소수력발전에서 수차의 최고 효율을 얻는 것은 매우 중요하나 개수로의 흐름에서 자유 수표면의 존재와 수로벽에 존재하는 마찰로 인하여 불균일한 유속 분포를 갖기 때문에 복잡한 요소로 인하여 이를 수학적으로 계산해 내지 못하고 있다. 본 논문에서는 실제와 비슷한 사각형 개수로 모형을 만들어 물리적 시뮬레이션을 수행하되 모형 환경에 자동 제어 장치를 부착하고 컴퓨터 프로그램을 통하여 2단계 유량 변화, 3단계 기울기 변화를 줄 수 있을 뿐 아니라 수로로 흐르는 물의 깊이를 잴 수 있게 하고, 물 깊이를 통한 10단계 흘수 변화에서 각 단계마다 30회씩 4회 시뮬레이션을 수행하고, 자료를 수집하고 분석하여 유량과 수로의 기울기, 흘수 변화에 따른 수차 회전 효율 특성의 다양한 경향을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.283-285
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• 2002

Boiler combustion systems are large, non-linear systems with numerous interactions between its component parts. In the analysis of such complex systems. dynamic simulation is recognized as a powerful method of keeping track of the myriad of interactions. This paper shows and discusses the developed analysis model, such as the forced draft fan the primary air fan, the furnace and burner system, pulverizer, air preheater and induced draft fan, etc. in accordance with BMCR condition of boiler using the Modular Modeling System(MMS) software.

• Current Research on Agriculture and Life Sciences
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• 제4권
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• pp.95-101
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• 1986

진동경운(振動耕耘)에 있어서 경운저항(耕耘抵抗) 및 동력(動力)을 최소(最小)로 하는 Computer에 의한 자동제어(自動制御) 시스템의 개발(開發)을 목적(目的)으로 3가지 Mode의 제어(制御) program을 작성(作成)하여 실험(實驗)과 Simulation을 통(通)하여 각 Mode의 제어성능(制御性能)을 조사(調査)하였다. 진동속도비(振動速度比)를 일정(一定)(1.5)하게 한 경우 3가지 Mode 모두 동일(同一) 진동조건(振動條件)에 수렴하였다. 그러나 흙의 전단주파수(剪斷周波數)에 Blade의 진동수(振動數)를 match 시키는 방법 즉 흙의 전단주파수(剪斷周波數)의 2배의 진동수(振動數)로 Blade를 진동(振動)시키는 제어(制御) Mode가 수렴 시간이 짧고, 견인저항 및 동력의 최적치(最適値)에 가장 가까웠다. 또 경심(耕深) 및 토양수분(土壤水分)의 변화(變化)와 같은 외란(外亂)에 대한 견인저항 감소율의 변동(變動)은 10%이하(以下)로 적었다. 이상(以上)과 같이 흙의 전단주파수(剪斷周波數)에 Blade의 진동수(振動數)를 match 시키는 제어(制御) Mode의 제어성능(制御性能)이 가장 우수함을 알았다.

• 한국생산제조학회지
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• 제21권3호
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• pp.387-393
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• 2012

It is very difficult to determine suitable cutting conditions in order to obtain accurate cutting profiles because machining errors caused by tool deflection depend upon cutting conditions. In this study the relationship between real cutting profiles (inclined shapes and machining errors) and cutting conditions was modeled in order to fabricate draft angle on micro molds. CCD (Central Composite Design) of DOE (Design Of Experiment) and RSM (Response Surface Method) were applied in order to model the relationship between cutting conditions and machining errors. In order to use CCD the range of radial depth of cut was chosen by $10-90{\mu}m$ and the range of feedrate was chosen by 200-300mm/min, and 9 points of cutting conditions were chosen inside determined ranges. Then, actual cutting processes were carried out as respect to 9 points of cutting conditions, draft angles and real cutting profiles were measured on cutting profiles, each response surface function was determined by conducting response surface analysis and the functions were represented by 3-dimensional graphs, contour lines and $101{\times}101$ matrices. Consequently it is possible to determine suitable cutting conditions in order to obtain arbitrary given draft angles and cutting profiles by using modeling. To validate proposed approach in this study suitable cutting conditions were determined by modeling in order to obtain arbitrary given draft angle and cutting profile, and actual cutting processes were carried out. About 95% of good agreement between predicted and measured values was obtained.