• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.145-147
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• 2005

This paper presents a methodology for satisfying the thermal comfort of Indoor environment and reducing the summer peak demand power by minimizing the power consumption for an Air-conditioner within a space. KEPCO(Korea Electric Power Corporation) use the fixed duty cycle control method regardless of the indoor thermal environment. This method has disadvantages that energy saying depends on the set-point value of the Air-Conditioner and DLC has no net effects on Air-conditioners if the appliance has a lower operating cycle than the fixed duty cycle. A variable duty cycle estimates the PMV(Predict Mean Vote) at the next step with a predicted temperature and humidity coming from the back propagation neural network model. It is possible to reduce the energy consumption by maintaining the Air-conditioner's OFF state when the PMV lies in the thermal comfort range. The proposed methodology uses the historical real data of Sep. 7th, 2001 from a classroom in seoul to verify the effectiveness of the variable duty cycle method comparing with fixed duty cycle. The result shows that the variable duty cycle reduces the peak demand to 2.6times more than fixed duty cycle and increases the load control ratio by 8% more. Based on the variable duty cycle control algorithm, the effectiveness of DLC is much more improved as compared with the fixed duty cycle.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.3.1-3.1
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• 2011

Over the past decade, the major efforts for lowering the cost of electronics has been devoted to increasing the packaging efficiency of the integrated circuits (ICs), which is defined by the ratio of all devices on system-level board compared to the area of the board, and to working on a larger but cheaper substrates. Especially, in flexible electronics, the latter has been the favorable way along with using novel nanomaterials that have excellent mechanical flexibility and electrical properties as active channel materials and conductive films. Here, the tool for achieving large area patterning is by printing methods. Although diverse printing methods have been investigated to produce highly-aligned structures of the nanomaterials with desired patterns, many require laborious processes that need to be further optimized for practical applications, showing a clear limit to the design of the nanomaterial patterns in a large scale assembly. Here, we demonstrate the alignment of highly ordered and dense silicon (Si) NW arrays to anisotropically etched micro-engraved structures using a simple evaporation process. During evaporation, entropic attraction combined with the internal flow of the NW solution induced the alignment of NWs at the corners of pre-defined structures. The assembly characteristics of the NWs were highly dependent on the polarity of the NW solutions. After complete evaporation, the aligned NW arrays were subsequently transferred onto a flexible substrate with 95% selectivity using a direct gravure printing technique. As proof-of-concept, flexible back-gated NW field effect transistors (FETs) were fabricated. The fabricated FETs had an effective hole mobility of 0.17 $cm2/V{\cdot}s$ and an on/off ratio of ${\sim}1.4{\times}104$. These results demonstrate that our NW gravure printing technique is a simple and effective method that can be used to fabricate high-performance flexible electronics based on inorganic materials.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.5
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• pp.426-437
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• 2007

off-design conditions, supersonic air inlets often encounter the problem of aerodynamic instability, called inlet buzz, which causes the significant degradation of the engine performance. An experimental and numerical study was conducted to investigate the phenomenon of supersonic inlet buzz on a generic, axisymmetric, external-compression inlet with a single-surface center-body. It is understood the mechanism of buzz onset as proving that the origin of buzz is the flow choking induced by separation at the intake throat. Also it is observed the intermittent and continuous buzz mode as area ratio varies and understood the transition process through this study. The buzz frequency become to be higher as decreasing the area ratio, but for each area ratio, the frequency of pressure oscillation is the same at all points of intake.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.39 no.1
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• pp.51-65
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• 2002

This paper presents a design method of the neural network-based controller using an indirect adaptive control method to deal with an intelligent control for chaotic nonlinear systems. The proposed control method includes the identification and control Process for chaotic nonlinear systems. The identification process for chaotic nonlinear systems is an off-line process which utilizes the serial-parallel structure of multilayer neural networks and simple state space neural networks. The control process is an on-line process which uses the trained neural networks as the system model. An error back-propagation method was used for training of identification and control for chaotic nonlinear systems. The performance of the proposed neural network controller was evaluated by application to the Duffing equation and the Lorenz equation, and the proposed controller was compared with other neural network-based controllers by computer simulations.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.1
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• pp.10-18
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• 2017

In this paper, we designed and implemented a visible light identification(VLID) system consisting of a VLID reader and a tag which backscatters incident lights from the reader. A VLID tag sends its ID to the reader by switching an LCD shutter which is located on its surface. The VLID reader consists of six LEDs and a photodiode(PD). The LEDs emit visible light and a PD located in a center position of LEDs receives backscattered light from the VLID tag. A microcontroller and a commercial liquid crystal display(LCD) shutter for 3D-TV glasses are used to implement a VLID tag. Experiments were conducted to confirm VLID system performance. We successfully demonstrated experiments to send NRZ-OOK signal of 100 bps over a distance of 35 cm at daytime. Also, we suggested the theoretical maximum transmission rate and the various methods to enhance the separation distance between a VLID reader and a tag.

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.1
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• pp.80-88
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• 2003

In this paper, the new robust torsional vibration suppression control scheme is proposed for the two mass system. A reduced order state feedback controller where the motor speed and the observed torsional torque are fed back and the PI controller are proposed as the torsional vibration suppression controller. Using the estimated mechanical parameters by off-line RLS(Recursive Least Square) algorithms, the speed controller for torsional vibration suppression is designed and its gains are determined using the Kharitonov robust control theory. The Kharitonov robust control theory can obtain the robust stability with a specified stability margin and a damping limit and the good performance of vibration suppression although if the parameters are varied within some specified limit. The effectiveness and usefulness of the proposed schemes are verified with the simulation and the experimental results on the fully-digitalized 5.5kW two mass system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.1
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• pp.79-87
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• 2013

A new modulation technique - correlative encoded FSK (CEFSK) - for use in power and bandwidth limited digital communication system is proposed. CEFSK is free of ISI and generates output signals which have a smooth and continuous phase transition and a reduced envelope fluctuation by keeping correlation between amplitude and phases of two subsequent symbols. In comparison to conventional one-bit differential detected (1DD) GFSK, the performance of the 1DD-CEFSK in a non-linearly amplified (NLA) channel impaired by additive white Gaussian noise (AWGN), ISI and IM, is analyzed via computer simulation. The simulation result shows that, in an NLA single-channel, 1DD-CEFSK provides a signal-to-noise ratio (SNR) advantage of up to 1.2dB and 0.8dB at BER of $1{\times}10^{-4}$ when input back-off (IBO) of HPA is -1.0dB and -3.0dB, respectively. For the same channel environment with multi-channel, 1DD-CEFSK outperforms 1DD-GFSK by 1.1dB in SNR, regardless of the value of IBO.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.2
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• pp.93-102
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• 2011

Existing research for store has been localized in that of Seoul area, and research for the Japanese style store built under the rule of Japanese Imperialism has not been done properly owing to national sentiment. This research established Naju that inland pillage is available along Yeongsan River after opening of Mokpo harbor. I will compare modernization developmental process of building of Korean style store with that of Japanese Style store, so obviously try to make clear the activities of modernization by linking social and economical change with Joseon merchants' life. I will try to light up the position of korean style store in Naju area in history of architecture by analyzing two styles of stores into urban architectural element, putting process of change in order and translating it according to flow of age. The development process of Korean restaurant stores and that of Japanese counterparts are rather relative. Whereas Japanese accumulated wealth through oppression and exploitation of the people of Joseon the former dynasty of present day Korea, the people of Joseon could not but be oppressed and depressed. On the other hand, while the dynamic liberation movements of Joseon merchants managed to develop based on the vitality that was growing ever more, Japanese chose to back down to some degree by exercising appeasing policy. The efforts to take initiative by shattering off the submissive attitude can be found from the ability fostering movement, Gwangju students campaign and new construction or remodeling of hanok the traditional Korean house as commercial building in the 1920s. The changing phase of the people breaking away from subjugated relation to subjective attitude can be found in the commercial districts.

• Journal of the Korean Society of Costume
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• v.29
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• pp.143-158
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• 1996

It was the year of 1903 when avantgarde artists in Vienna gave a birth to the Wiener Werkstaette under the influence of Aesthetic Movement and Guild of Handicraft from England. This study is on the backgrounds of the birth of the Wiener Werkstaette its artis-tic motto and world-wide echo it provoked. This thesis goes back to the time when the decadent Wiener Secession shaped up refiewing the Reform Movement It also covers characteristics works of major members of the Wiener Werkstaette which were produced on the basis of the concept of Gesmtkunstwerk, The conclusion of this study is that : 1. Without losing its own specifc features various fields of formative arts were combinded together coherently and succeeded to realize the idealistic art that is the com-posite are 2. The Wiener Werkstaette was strongly opposed to the ready-made clothes which be-came popular as the society was Industrialized and commercialized. unlike those ready-to-wear clathes those members of the Wiener Werkstaette preferred to make each clothes with different mateirals and printed their own unique pattern designs. 3.As a results of close relationships between the Wiener Werkstaette and paul poiret 'Stu-dio Martine' was established in paris and new pattern deslhns were introduced by Raoul Dufy. 4. After the break-out of World War One cultural exchanges with other foreign countries were vuirtually cut off and the Wiener Werkstaette was disconnected from the influence of Parisl That was the motive for Wiener Werkstaette to start building up its unique artistic style with peculiar materials techniques and methods of productionl Those brisk and creative activities of the Wiener Werkstaette brought forth "the Golden perlod of 1920s" 5. Its historic design and ornamental pattern were assessed as a prelude to the Post-mod-ernism Since the late 1970s with the redis-covery of the culture of vienna in 1900s. the Art to wear which was created by the 'Wiener Werkstaette' but unfortunately tucked away by the Greate Depression and nationalism has been revaluated and studied. In Korea it was since 1985 when 'the art to wear' began to gain attention widely. It is urged that the theory of the 'Gesamtkunstwerk' should be also ac-cepted and shared earnestly.

• Fashion & Textile Research Journal
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• v.10 no.4
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• pp.489-498
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• 2008

This study is on the image evaluation of the hair up-style and the wedding dress styles of prospective brides. Based on some prior theoretical studies, and information obtained from wedding magazines and interviews conducted at the beauty business places, four kinds of the hair up-style were selected, namely, top-point, golden-point, back-point, and nape point. Three styles of necklines were selected: boat necklines, V-necklines, and off-shoulder necklines. The surveyor herself did the hair styling for models, and dressed up the models, to produce the stimuli. And the stimuli were presented to percipients along with questionnaires for measuring the image evaluations. Prepared were total 12 different kinds of stimuli, in which four hair up-styles and three dress styles were combined into 12 combinations ($3^*4$), and, with respect to these 12 stimuli, 26 itemized questions were included in the questionnaire. From the factor analysis on the image evaluation of the hair up- style and wedding dresses, five factors were derived as fallowing: attractiveness, boldness, purity, cuteness, feminity. This study revealed that wedding dress styles are more sensitive to the contemporary trend, compared to the hair styles; and the selection in the wedding style is quite influenced by the dress style, but not by the hair up-style. Also, prospective brides evaluated the hair up-styles and the wedding dress styles separately without recognizing their mutual relationship, and thus did not recognize the two as the mutually coordinated relationship, but rather recognize the two as two separate elements.