• KEPCO Journal on Electric Power and Energy
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• v.2 no.3
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• pp.425-431
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• 2016

Supply Capability of the generator, if the maximum demand occurs, refers to the maximum power that can be stably supplied and it is possible to maintain stable power supply to be greater than actual load. However, unexpected power demand and reduction in supply Capability due to stop of unexpected generator in operation can temporarily make a big chaos in power system. In fact, due to a lack of power supply Capability in the country, enforced emergency load adjustment to the September 15, 2011, the circulation power outage has occurred in several cities. As the result, interrupted operation of the elevator and stopped hospital medical equipment led to a great deal of trouble to people's lives, causing a social problem. At that time, it was found that a failed frequency control because of smaller actual supply Capability than that of predicted. The difference was about 1,170 MW with Gas turbine power plant. By accurately calculating the generator supply capability, we can not only grasp the power reserve rate, but also correspond to the time of power supply instability.

• Journal of Mechanical Science and Technology
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• v.17 no.5
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• pp.776-783
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• 2003

A low speed wind tunnel test was conducted for full-scale model of an unmanned aerial vehicle (UAV) in Korea Aerospace Research Institute (KARI) Low Speed Wind Tunnel(LSWT). The purpose of the presented paper is to illustrate the general aerodynamic and performance characteristics of the UAV that was designed and fabricated in KARI. Since the testing conditions were represented minor portions of the load-range of the external balance system, the repeatability tests were performed at various model configurations to confirm the reliability of measurements. Variations of drag-polar by adding model components such as tails, landing gear and test boom are shown, and longitudinal and lateral aerodynamic characteristics after changing control surfaces such as aileron, flap, elevator and rudder are also presented. To explore aerodynamic characteristics of an UAV with model components build-up and control surface deflections, lift curve slope, pitching moment variation with lift coefficients and drag-polar are examined. The discussed results might be useful to understand the general aerodynamic characteristics and drag pattern for the given UAV configuration.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.12
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• pp.1170-1176
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• 2010

This study addresses adaptive control of UAVs(Unmanned Aerial Vehicles) pitch-axis maneuver. The MRAC(Model Referenced Adaptive Control) approach is employed to accommodate uncertainties which are introduced by feedback linearization of pitch attitude control by elevator input. The model uncertainty is handled by adaptation laws which update model parameters while the UAV is under control by the feedback control law. Steady-state pitch attitude achieved by the stabilizing control law is derived to provide insight on the closed-loop behavior of the controlled system. The proposed idea is free of linearization, gain-scheduling procedures, so that one can design high maneuverability of UAVs for pitching motion in the presence of significant model uncertainty.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.1
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• pp.68-78
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• 2014

Recently, companies are trying to gain a competitive advantage in the market to meet the voice of customer. For this purpose, QFD has been used as product development technology in many areas to include the customer' requirements. Also, Kano model has been used to understand the customer' requirements for an effective way. Therefore integration of Kano model and QFD can more efficiently reflect the customer' requirements when designing a new service. This paper proposes PI index by taking into account the current satisfaction position of our company and competitors while IR (Improvement Ratio) value was set uniformity. This study suggests a more accurate index to predict potential improvements and calculates the final importance or priority. Through case studies targeted at elevator maintenance companies, we can have a general idea how much to improve in the near future and estimate the final importance of customer requirements.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.5
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• pp.18-23
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• 2004

Wind tunnel test for Forward-Swept wing airplane model, a part of the Korea-Russia technical cooperation program has been conducted at both TsAGI T-102 and KARI LSWT. The results of TsAGI T-102, obtained by using a unique wire-suspension model support system, and KARI LSWT, used tripod and tandem strut arrangement configuration, are compared with various model conditions including control surface deflection such as flap, aileron, elevator and rudder. Good agreement in the value of drag-polar is observed between TsAGI T-102 and KARI LSWT data. The lateral and directional stability coefficients with rudder and aileron deflection represent a good agreement in both facility.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.205-207
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• 2014

This paper uses $Color-x^2$ histogram that is composed of merits of color histogram and ones of histogram, in order to efficiently extract violent scenes in elevator. Also, we use a threshold so as to find out key frame, by use of existing $Color-x^2$ histogram. To increase the probability that discerns whether a real violent scene or not, we take advantage of statistical judgments with 20 sample visual images.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.2
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• pp.3-10
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• 2019

The purpose of the study is to survey the effective methodology of composition and connection for the third pedestrian routes in mixed-use building by case studies. The study is performed as follows: First of all, pedestrian routes are classified into malling route, evacuation route, and the Third route. Secondly, case studies are conducted based on the classification. Thirdly, it is investigated about the composition and connection of the malling and the Third pedestrian route. The investigation is focused on gate, path, central area, vertical circulation(EV and escalator) and the four circulation elements. Finally, the effective methodology is extracted for setting the Third route in mixed-use buildings. The conclusion of the study is as follows: The enhancement of consistency and connection between the main route and the Third route is important for providing convenient paths especially to users who needs shortcut, EV/ES users. Additionally, the connections between EV and gate, between shortcut and EV/ES should be increased to enable users choosing their path as needed.

• Journal of Aerospace System Engineering
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• v.14 no.5
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• pp.1-8
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• 2020

The aeroservoelastic analysis that deals with the interactions of the inertial, elastic, and aerodynamic forces and the influence of the control system have been performed. MSC Nastran was used for the free vibration analysis of the structure model as the pre-analysis. ZAERO was used to calculate the unsteady aerodynamic forces. The unsteady aerodynamic forces were verified by comparing with Doublet Hybrid Method. Karpel's Minimum-State Approximation method was used for approximation of the aerodynamic forces to the Laplace domain in the frequency domain. The aeroservoelastic state-space equation was obtained by combining the aeroelastic equation with the actuator dynamics. The analysis of aeroservoelastic stability concerning the elevator input of the high aspect ratio model was performed. The root-locus method and time-integration method were used for the analysis of aeroservoelastic in frequency and time domain.

• Journal of KIISE:Software and Applications
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• v.30 no.5_6
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• pp.587-597
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• 2003

The C language is widely adopted for safety-critical systems. However, it is known that the C language is an unsuitable choice for safety-critical system since the C language includes several bad language features such as heavy use of pointers. The aim of this work is to define safe subset of the C language and translate the subset into the SPARK Ada so that we can verify the program's safety using SPARK analysis tools. SPARK is a safe subset of Ada and has been successfully applied to high integrity system development. The C program translated into SPARK has the same integrity level as SPARK, and the program correctness can be verified by using Examiner which is a SPARK analysis tool. An elevator controller case study is presented and is used to demonstrate the potential use of our approach to implement a realistic system. We also developed a translator that automatically translates C code into SPARK in accordance with the translation rules.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.2
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• pp.224-229
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• 2005

Generally, genetic algorithm (GA) has too much time and space complexity when it is running in the typical processor. Therefore, we are forced to use the high-performance and expensive processor by this reason. It also works as a barrier to implement real device, such a small mobile robot, which is required only simple rules. To solve this problem, this paper presents and proposes enhanced processor-architecture for the faster GA processing. A typical processor architecture can be enhanced and specialized by two approaches: one is a sorting network, the other is a residue number system (RNS). A sorting network can improve the time complexity of which needs to compare the populations' fitness. An RNS can reduce the magnitude of the largest bit that dictates the speed of arithmetic operation. Consequently, it can make the total logic size smaller and innovate arithmetic operation speed faster.