• Journal of Institute of Control, Robotics and Systems
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• v.20 no.11
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• pp.1103-1111
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• 2014

The results of control law design for a tilt-rotor unmanned aerial vehicle that has a nacelle mounted wing extension (WE) are presented in this paper. It consists of a control surface mixer, stability and control augmentation system (SCAS), hold mode for altitude / speed / heading, and a guidance mode for preprogram and point navigation which includes automatic take-off and landing. The conversion corridor and the control moments derivatives between the original tilt-rotor and its variant of the nacelle mounted WE were compared to show the effectiveness of the WE. The nacelle conversion of the original tilt-rotor starts when the airspeed is greater than 30 km/h but its WE variant starts at 0 km/h in order to reduce the drag caused by the high incidence angle of the WE. The stability margins of the inner loop are presented with the optimization approach. The outer loops for the hold mode are designed with trial and error methods with linear and nonlinear simulation. The main control parameter for altitude control of the helicopter mode is thrust command and it is transferred to the pitch attitude command in airplane mode. Otherwise, the control parameter for the speed of the helicopter mode is the pitch attitude command and it is transferred to the thrust command in airplane mode. Therefore the speed and altitude hold mode are coupled to each other and are engaged at the same time when an internal pilot engages any of the altitude or speed hold modes. The nonlinear simulation results of the guidance control for the preprogrammed mode and point navigation are also presented including automatic take-off and landing in order to prove the full control law.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.2
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• pp.227-235
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• 2017

In this paper, a systematic 5-mode(road steering, all-wheel steering, crab steering, reduced swing out mode and independent steering) steering algorithm design process for an all-terrain mobile crane with 5 axles and all steerable wheels is proposed. Steering angles for each steering mode are designed based not only on basic theory but also on vehicle specification, design limitation and requirements. A multi-body dynamic analysis is carried out to investigate the feasibility of the steering algorithm. According to the results, the proposed steering algorithm meets the objective of each steering mode.

• Earthquakes and Structures
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• v.4 no.4
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• pp.341-363
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• 2013

Earthquake response calculation, parametric analysis and seismic parameter optimization of base-isolated structures are some critical issues for seismic design of base-isolated structures. To calculate the earthquake responses for such non-symmetric and non-classical damping linear systems and to implement the earthquake resistant design codes, a modified complex mode superposition design response spectrum method is put forward. Furthermore, to do parameter optimization for base-isolation structures, a graphical approach is proposed by analyzing the relationship between the base shear ratio of a seismic base-isolation floor to non-seismic base-isolation one and frequency ratio-damping ratio, as well as the relationship between the seismic base-isolation floor displacement and frequency ratio-damping ratio. In addition, the influences of mode number and site classification on the seismic base-isolation structure and corresponding optimum parameters are investigated. It is demonstrated that the modified complex mode superposition design response spectrum method is more precise and more convenient to engineering applications for utilizing the damping reduction factors and the design response spectrum, and the proposed graphical approach for parameter optimization of seismic base-isolation structures is compendious and feasible.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.9
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• pp.157-165
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• 2002

The design of hydraulic & control system has been developed for the disc spinning machine. The hydraulic system has been designed in the overall system including the vertical & horizontal slide fur spinning works which are controlled by hydraulic servo valves in right & left side, and the clamping slide for holding & pressing blank material in center during spinning process. Based on the design concept of this hydraulic system, model test experiments for hydraulic servo control system is tested to conform confidence and applying possibility. The control system is introduced with the fuzzy-sliding mode controller for the hydraulic force control reacting force as a disturbance, because a fuzzy controller does not require an accurate mathematical model for the generation of nonlinear factors in the actual nonlinear plant with unknown disturbances and a sliding controller has the robustness & stability in mathematical control algorithm. We conform that the fuzzy-sliding mode controller has a good performance in force control for the plant with a strong disturbance. Also, we observe that a steady state error of the fuzzy-sliding mode controller can be reduced better than those of an another controllers.

• Journal of the Korean Society of Costume
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• v.59 no.8
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• pp.1-14
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• 2009

This study was aimed to make clear fashion is an expression art displaying not only functional or commercial aspects, but creative functions as an artistic work by analyzing Art Mode and its values, and to help develop more creative design by combining fashion with art. In terms of method, relevant documents, precedent studies, and the works announced in domestic and foreign fashion collections, such as Vogue, Fashion News, Gap, and Collections from 2000 to 2009. According to the findings, artistic works were used by the Art Mode in modern fashion. The respect of artists was expressed using historic famous painting works or current works in various fields, designers' individuality was shown by directly applying work messages to clothes, and fashion design was converted into a tool to communicate the messages like artistic works. Second, the various styles, using the formative character of modern art styles from animalism to modern abstractism, showed the creativity of design, transformed art into the art that enables to see the image of modern art, and presented the possibility of developing into a newer creative design through the application of numerous art styles and the transformation of ideas. Third, the collaboration with artists was used. Fashion designers or fashion brands tried to change the images of works or brands in partnership with artists or to increase differentiated images. The future direction of fashion is a pursuit of new form and content to express fashion, not simply to use artistic works. It is expected that such pursuit will lead to more creative and artistic fashion design.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.354-358
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• 1996

At design stage of the TRXI agricultural tractor transmission (New product of TongYang Moolsan Co., Ltd), the noise and vibration of the transmission were analyzed theoretically for the optimal design of the transmission . For this analysis, the finite element model was developed using a commercial computer software, ANSYS. The noise and vibration of the TRXI transmission housing were predicted by the modal analysis. Natural frequency of the TRXI transmission housing was ranged from 12.53Hz(1st mode ) to 30.05Hz(5th mode). The fifth mode took place at the bearing metal in the area of rear transmission housing and was very close to the gear mesh frequency (30.5Hz) of low rang gear at the low creep shifting . Based on the results , the bearing metal of the range shift housing was reenforced with the rib at design stage.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1891-1895
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• 2003

Switch-mode power supplies (SMPS) have become a major source of conducted electromagnetic interference (EMI) which is the combination between differential mode (DM) noise and common mode (CM) noise. This paper presents the conducted EMI reduction approach in flyback switched mode power supply by rerouting for circuit balance to reduce common mode noise. And differential mode noise can be reduce by adding $c_x$ capacitor across the input power line, and passive element to the gate drive of switching device MOSFET to slow down the switching times. This combination of our approach is the effective way to reduce the conducted EMI and it is also a cost effective for product design

• Journal of Internet Computing and Services
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• v.17 no.5
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• pp.43-49
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• 2016

This paper presents a workflow validation method for data-intensive graphical workflow models using real-time workflow tracing mode on data-intensive workflow designer. In order to model and validate workflows, we try to divide as modes have editable mode and tracing mode on data-intensive workflow designer. We could design data-intensive workflow using drag and drop in editable-mode, otherwise we could not design but view and trace workflow model in tracing mode. We would like to focus on tracing-mode for workflow validation, and describe how to use workflow tracing on data-intensive workflow model designer. Especially, it is support data centered operation about control logics and exchange variables on workflow runtime for workflow tracing.

• Journal of Internet Computing and Services
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• v.17 no.5
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• pp.131-139
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• 2016

This paper presents a workflow validation method for data-intensive graphical workflow models using real-time workflow tracing mode on data-intensive workflow designer. In order to model and validate workflows, we try to divide as modes have editable mode and tracing mode on data-intensive workflow designer. We could design data-intensive workflow using drag and drop in editable-mode, otherwise we could not design but view and trace workflow model in tracing mode. We would like to focus on tracing-mode for workflow validation, and describe how to use workflow tracing on data-intensive workflow model designer. Especially, it is support data centered operation about control logics and exchange variables on workflow runtime for workflow tracing.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.4
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• pp.304-311
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• 2004

In this paper we present a technique of discrete-time sliding mode controller design for assigning eigenvalues of sliding mode and determining a convergence rate to sliding surface. First the sliding mode coefficient is designed via Ackermann s formula. Then a linear controller is designed to enforce sliding mode such that the resulting closed loop yields the desired eigenvalues. As we use a linear control instead of nonlinear control, chattering is nearly eliminated. Simulation and experimental results are included to show the effectiveness of the proposed method for Laser Marking System.