• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.1
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• pp.145-152
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• 2019

A composite guidance scheme is proposed for air-to-ground anti-tank missiles launched from an airborne platform. Long-range anti-tank missiles usually use a fiber optic line (FOL) for the datalink between an operator and the missile to obtain real-time target information and to command the missile. Also, impact angle control is used to maximize the warhead effectiveness, but it should be carefully implemented due to interference between the launch platform and the FOL. Thus, the proposed guidance scheme takes into account both impact angle and FOL constraints. Under system lag and acceleration limits, a selection method of guidance gains and calculation logic of the maximum achievable impact angle are proposed for a guideline of practical implementation. The performance of the proposed guidance scheme is investigated by nonlinear simulations with various engagement conditions.

• Journal of Environmental Impact Assessment
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• v.13 no.5
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• pp.263-276
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• 2004

This research is primarily intended to propose a new concept for aggregate control of impervious coverage using remote sensing and GIS. An empirical study for a case study site was conducted to demonstrate how a standard remote sensing and GIS technology can be used to assist in implementing the aggregate control for impervious coverage as intermediary between decision makers and scientists. Guidelines for a replicable methodology are presented to provide a strong theoretical basis for the standardization of factors involved in the aggregate control; the meaningful definition of land mosaic in terms of pervious areas, classification of pervious intensity, change detection for pervious areas. Detailed visual maps (e.g. estimation of impervious surface allowable) can be generated over large areas quickly and easily to increase the scientific and objective decision-making for the aggregate control. It is anticipated that this research output could be used as a valuable reference to confirm the potential of remote sensing and GIS in the aggregate control for impervious coverage.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.2
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• pp.186-192
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• 2014

Recently wind energy penetration into power systems has increased. Wind power, as a renewable energy source, plays a different role in the power system compared to conventional power generation units. As long as only single and small wind power units are installed in the power system, wind power does not influence power system operation and can easily be integrated. However, when wind power penetration reaches a significantly high level and conventional power production units are substituted, the impact of wind power on the power system becomes noticeable and must be handled. The connection of large wind turbines and wind farms to the grid has a large impact on grid stability. The electrical power system becomes more vulnerable to and dependent on wind energy production, and therefore there is an increased concern about the large wind turbines impact on grid stability. In this work, a new type of fuzzy logic controller for the frequency control of wind farms is proposed and its performance is verified using SimWindFarm toolbox which was developed as part of the Aeolus FP7 project.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.7
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• pp.508-516
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• 2019

In this paper, we propose a guidance law to control Impact Angle in consideration of look angle limit of the missile with strapdown seeker on the non-maneuvering target. The proposed law is based on sliding mode algorithm and generates acceleration commands using look angle and line of sight information provided by the strapdown seeker and navigation system. And, target velocity and target path angle are provided by like TADS (Target Acquisition and Designation System) at launch time. We can confirm that the target interception and impact angle control are possible through the convergence of the proposed sliding surface. In addition, it is possible to confirm that the sign of derivative result of the look angle at the maximum and minimum look angle is opposite to the sign of the look angle, so the look angle limit is not exceeded.

• International Journal of Automotive Technology
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• v.3 no.4
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• pp.137-145
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• 2002

Automobiles should be designed to meet the requirements and standards for the protections of passengers in a car accident. One of safety factors is an absorbing capacity in collision. Many vehicles have been designed based on the criterion of the absorbing capacity. Therefore a controller has been developed in order to control and increase the absorbing capacity of impact energy in automobile collision. The capacity of impact energy will be improved regardless of vehicular-structure members and shapes. An air-pressure horizontal impact tester for crushing has been built up for the evaluation of energy absorbing characteristics in collision. Influence of height, thickness and clearance in the controller have been considered to predict and control the energy absorbing capacity. Aluminum alloy (Al) tubes (30,39,44 m in inner dia. and 0.8, 1.0, 1.2 m in thickness) are tested by axial loading. The energy absorbing capacity of Al tubes have been estimated in cases of with-controller and without-controller. respectively based on height. thickness, clearance of an controller.

• Journal of Advanced Navigation Technology
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• v.16 no.1
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• pp.8-15
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• 2012

This paper on the assumption that the target is stationary and the velocity of missile is fixed value. In three dimensional space. Using flight path angle to simultaneous control impact-time-and-angle base on a homing guidance law. The independent variable in the nonlinear engagement model is the flight path angle of the missile. The propose homing guidance law can see the controllability of impact-time-and-angle. And also can see the processing of the missile arrive at the target. It is applied to several salvo attack scenarios. The performance of the proposed guidance law is verified by simulations.

• East Asian Journal of Business Economics (EAJBE)
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• v.5 no.4
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• pp.50-66
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• 2017

Purpose - The purpose is to identify a structural effect relationship among a hotel chef's personal competency, job satisfaction and customer orientation. Moreover, this research tries to provide implications regarding effective human resource management strategies based on competency to strengthen job satisfaction and customer orientation by testifying the effect relationship of job satisfaction with the relationship between personal competency and guest orientation. Research design, data, methodology By targeting chefs working in five starred hotels in Seoul, the surveys have been distributed from April 1st of 2017 to April 20th of 2017 (approximately 20 days). Out of 300 distributed surveys, 250 were collected, and 246 were used, excepting 4, unhonestly answered. Results - It has been analyzed that a hotel chef's personal competency, self-control ability, customer orientation competency, interpersonal relation competency, gumption, and professional competency has a significant effect on job satisfaction, however, it has been identified that gumption has no impact on job satisfaction. Job satisfaction has a significant impact on customer orientation. Lastly, there is a control effect on job satisfaction and customer orientation by organizational commitment Conclusions - It is able to propose the solutions to improve customer orientation, job satisfaction and organizational commitment of a hotel chef and the ways for human resource management.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.743-748
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• 1998

As nation's infrastructure is getting old, nondestructive evaluation of existing structures and construction quality control are getting important. In this thesis, flaw detection techniques of concrete members with asphalt using impact echo test were introduced. This techniques are based on stress wave propagation. In this field impact echo test, As load is gradually increased, frequency is increased. From this change of frequency through impact echo test, we can detect that the crack of bridge ascends and what the depth of crack is.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.303-310
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• 2008

In Korea, the current noise impact assessment has not yet considered the vertical noise propagation property by buildings and other obstacles. And noise control plan has been established without conducting the economic assessment for the noise control facilities. A noise map is used to calculate the noise level based on a theoretical formula or an empirical formula, and also predict the characteristics of vertical propagation by linking with a geometry data. And It is Possible to analyze cost-effect of noise control facilities by consider installation costs. In this study, we addressed the application of noise map for noise impact assessment and cost-effect analysis of noise control facilities.

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.72-75
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• 1988

In the point-to-point motion on servo system, the control mode which minimizes the performance index including, the impact of end point, time and energy, is proposed. The proposed control mode applied to the feed-back control system of D.C motor and then had a computer simulation. This control mode had less the impact of end point, stedy state error, time and energy than the bang-bang or the saturating- proportional control mode.