• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.143-145
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• 2005

There has been increasing interest in the renewable energies. Wind energy is worldwide number one renewable energy from the installed capacity viewpoint. Most of the power systems utilizing wind energy are connected to other large systems. In such integrated systems, frequency control is not big issue. Rut the situation is different in isolated systems like Korean power system. It is important to assess appropriate capacity of wind power for our system, as it affects the system operation and control strategy. In this paper we made it clear the relationship among generator inertias, governor droop, system damping and wind energy capacity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.9
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• pp.1186-1191
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• 2014

Weekly and monthly electric load forecasting are essential for the generator maintenance plan and the systematic operation of the electric power reserve. This paper proposes the weekly maximum electric load forecasting model for 104 weeks with the multiple regression model. Input variables of the multiple regression model are temperatures and GDP that are highly correlated with electric loads. The weekly variable is added as input variable to improve the accuracy of electric load forecasting. Test results show that the proposed algorithm improves the accuracy of electric load forecasting over the seasonal autoregressive integrated moving average model. We expect that the proposed algorithm can contribute to the systematic operation of the power system by improving the accuracy of the electric load forecasting.

• The Korean Journal of Pharmacology
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• v.4 no.1 s.5
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• pp.37-39
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• 1968

A method for presenting the heart rate of intact animals as a kymographic record is described. A transistorized impulse generator with a dry battery power supply is used to produce pulses. The pulses are integrated and make a pen motor drived. The ability of the instrument to follow a wide range of heart rate change is demonstrated. The instrument is especially usefull to observe an acute and transitory heart rate change. A method for changing the heart beat to sound and a method for counting the heart rate of intact animal and isolated preparations by employing post office counter were also described.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.529-530
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• 2006

분산형 전원이 전력계통에 연계됨에 따라 역조류, 보호협조, 계통 동기화, 전기품질 문제 등 여러 가지 문제를 야기한다. 이에 따라 전력회사에서는 분산형 전원의 계통연계 기술 기준을 제시하고 해당 분산형 전원의 계통 연계에 대한 기술 검토를 수행한다. 본 논문에서는 동기발전기형 2500KVA 소수력발전기 2대의 배전계통 연계에 대한 기술적 검토를 수행하였으며 해당 분산형 전인이 동기발전기임을 고려하여 계통연계시 상시전압변동 및 보호방식에 대해 집중 분석하였다. 먼저 소수력발전기가 연계되는 지점에서의 기존 선로 및 전력설비의 여건과 소수력발전기의 출력용량 및 역률을 고려하여 연계 지점에서의 전압변동을 검토하여 적절한 연계방식을 제시한다. 그리고 시간대별 소수력발전기의 발전량과 해당 배전선로의 부하량을 고려하여 기 설치된 보호계전기에 의한 단독운전 검출 능력을 검토하고자 한다.

• Journal of computational fluids engineering
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• v.5 no.2
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• pp.28-37
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• 2000

An integrated grid generation has been developed for a Navier-Stokes simulation of flow fields inside multistaged turbomachinery The internal grids are generated by the combination of algebraic and elliptic methods. The interactive mode of the present system is coupled efficiently with the design results and flow solvers. Application to several types of axial-flow turbomachines was demonstrated to be reliable and practical as the pre-processor of the computational fluid engineering for gas turbine engines.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.9
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• pp.781-786
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• 2015

Recently, studies of 3D printing methods have been working in various applications. For example, the powder base method laminates the prints by using a binding or laser sintering method. However, the draw back of this method is that the post process is time consuming and does not allow for parts to be rapidly manufactured. The binding method requires the post process while the time required for the post process is longer than the manufacturing time. This paper proposes a UV curing binding method with an integrated piezo printing head system. The optimization of an arbitrary waveform generation for the control of a UV curable resin droplet was researched, in addition to developed optimized UV curing processes in multi nozzle ink jet heads.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.676-677
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• 2015

본 논문에서는 매입형 영구자석 동기전동기로 Belt-Type ISG(Integrated Starter Generator)를 설계하였다. 전동기는 저속영역에서 동손이 크고, 고속 영역에서는 철손의 비중이 크게 나타난다. ISG의 경우 전동기로 동작하는 저속영역은 동작시간이 짧기에 효율이 크게 중요하지 않지만 발전기동작은 고속영역에서 장기간 이루어지기에 이 구간에서 효율을 높이는 것이 중요하다. 특히 분포권에서는 전체 손실성분 중에서 회전자의 영구자석 기본파와 고조파 기자력에 의해 발생하는 치에서의 철손이 가장 큰 비중을 차지한다. 본 논문에서는 분포권에서의 철손에 대해서 분석하고 주된 손실의 원인인 치에서의 철손을 저감하는 설계를 수행하여 효율을 향상시켰다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1429-1430
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• 2015

The present study developed an air flow generator system with standard syringes usually adapted for spirometer calibration. It consisted of servo-motor, driver, linear robot, and controller operating as a whole integrated system capable of generating air flows at different speeds on two identical 3L syringes. Experiments demonstrated high accuracy in both flow and volume generation as required such that relative errors were approximately 2.1% and 0.5%, respectively.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.623-628
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• 1998

A new advanced integral reactor of 330 MWt thermal capacity named SMART (System-Integrated Modular Advanced Reactor) is currently under development in Korea Atomic Energy Research Institute (KAERI) for multi-purpose applications. Modular once-through steam generator (SG) and self-pressurizing pressurizer equipped with wet thermal insulator and cooler are essential components of the SMART. The SMART Provides safety systems such as Passive Residual Heat Removal System (PRHRS). In this study, a computer code for performance analysis of the PRHRS is developed by modeling relevant components and systems of the SMART. Using this computer code, a performance analysis of the PRHRS is performed in order to check whether the passive cooling concept using the PRHRS is feasible. The results of the analysis show that PRHRDS of the SMART has excellent passive heat removal characteristics.

• Journal of the Korean Professional Engineers Association
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• v.34 no.5
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• pp.40-43
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• 2001

In order for the World cup football game to be operated stably with duplicate service electric power supply, It is done, emergency generator and the U.P.S it establishes. the electric power system power control, lighting control, integrated monitoring. rue fighting. obstruction light, the searchlight, snow melting, electric erosion shield. grounding, the lightening protection and viewable lighting, stadium floodlight and an electric bulletin board it composed of the back which it sells.