• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.1407-1412
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• 2004

Impedance calculations of electric railway traction systems is essential to define characteristics and to design it. The self impedance is defined voltage drop rate per unit length, the mutual impedance is represented as a voltage induced to transmission line from transmission line. The self and the mutual impedance are influenced by ground return currents. The earth is considered as a semi-infinitely extended non-ideal conductor. The current of transmission line produces earth current induced magnetically and it flow through a path having minimum impedance. Carson proposed the impedance calculation formula using wave equations and magnetic field equations. Though the formula have an improper equation, that is still used as a standard impedance calculation method. This paper introduced an impedance calculation method that the complex depth of earth return method assumes that the current in conductor returns through an imagined earth depth path located directly under original conductor at a depth of. In this paper, we showed that this proposed method has a closed form and is easier than Carson's.

• 대한기계학회논문집B
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• 제33권1호
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• pp.28-38
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• 2009

Numerical simulation is performed for microdroplet deposition on a pre-patterned micro-structure. The liquid-air interface is tracked by a level-set method, which is improved by incorporating a sharp-interface modeling technique for accurately enforcing the matching conditions at the liquid-gas interface and the no-slip condition at the fluid-solid interface. The method is further extended to treat the contact angle condition at an immersed solid surface. The present computation of a patterning process using microdroplet ejection demonstrates that the multiphase characteristics between the liquid-gas-solid phases can be used to improve the patterning accuracy.

• Bulletin of the Korean Chemical Society
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• 제15권5호
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• pp.369-374
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• 1994

Self-assembled (SA) and Langmuir-Blodgett (LB) monolayers of arachidic acid on silver surfaces have been investigated by a reflection-absorption Fourier transform infrared spectroscopy. Arachidic acid was adsorbed on silver as carboxylate with its two oxygen atoms bound symmetrically to the surface. Although both the SA and LB monolayers consisted of fully extended trans zigzag carbon chains, a closer examination indicated that the SA monotayers should possess a more ordered crystalline structure than the LB monolayers. The infrared spectral data dictated that the extent of methyl group exposure at the air-film interface was greater in the SA monolayers than the LB monolayers, in agreement with the contact angle measurement. From a theoretical analysis, the alkyl chains in each monolayers seemed to be tilted away from the surface normal by less than $3.5^{\circ}$, but in opposite directions. Arachidic acid monolayers were concluded to have same structure as stearic acid monolayers.

• Journal of Information Processing Systems
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• 제18권4호
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• pp.510-523
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• 2022

Considering the problems of poor control effect, weak disturbance rejection ability and adaptive ability of two-wheeled self-balanced robot (TWSBR) systems on undulating roads, this paper proposes a fuzzy neural network active disturbance rejection controller (FNNADRC), that is based on fuzzy neural network (FNN) for online correction of active disturbance rejection controller (ADRC)'s nonlinear control rate. Firstly, the dynamic model of the TWSBR is established and decoupled, the extended state observer (ESO) is used to compensate dynamically and linearize the upright and displacement subsystems. Then, the nonlinear PD control rate and FNN are designed, and the FNN is used to modify the control parameters of the nonlinear PD control rate in real time. Finally, the proposed control strategy is simulated and compared with the traditional ADRC and fuzzy active disturbance rejection controller (FADRC). The simulation results show that the control effect of the proposed control strategy is slightly better than ADRC and FADRC.

• 한국콘텐츠학회논문지
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• 제14권11호
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• pp.713-721
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• 2014

본 연구는 지방공무원들의 셀프리더십이 직무만족과 고객지향성에 미치는 영향을 경험적으로 파악하여 정책적 시사점을 도출할 목적으로 수행되었다. 그동안 행정서비스를 국민의 필요와 욕구에 맞춰 제공하기 위한 다양한 제도적 방법이 도입되어 왔지만 만족할 만한 얻지 못했다. 제도적 접근만으로는 관료들이 직무수행 행태를 고객지향적 행동으로 바꾸는데 한계가 있기 때문이다. 오랜 공무원들의 서비스 공급자 중심의 역할인식과 직무수행방식을 수요자 중심으로 바뀌는 데는 많은 시간이 필요한 것이다. 셀프리더십은 조직구성원의 자발적이고 능동적 행동을 통한 내적에너지를 업무수행에 활용하는 능력으로 조직목표달성에 긍정적 영향을 미치는 요인이다. 본 연구의 분석 결과 셀프리더십이 공무원의 고객지향성에 긍정적으로 영향을 미치는 것으로 확인되었으며 직무만족도가 매개적 역할을 수행하고 있음도 제시하였다. 행정서비스의 고객지향성을 강화하기 위해서는 제도적 통제를 받지 않아도 자기 스스로 자신의 태도와 행동을 긍정적 방향으로 바꿀 수 있도록 셀프리더십을 향상시키는 정책적 접근을 제안하였다.

• 한국전자거래학회지
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• 제12권4호
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• pp.165-184
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• 2007

블로그는 정보 공유와 관계 형성의 유력한 미디어로 인정되고 있다. 그러나 기존의 기술 수용 모델은 블로그와 같은 관계 지향적인 정보시스템에 대한 수용성을 설명하는 데 적합한지 증명되지 않은 상태이다. 따라서 본 연구의 목적은 블로그 사용에 영향 주는 요인을 규명하는 것이다. 이것을 위해 유력한 포털사이트인 네이버 블로거들을 대상으로 인지된 유용성 인지된 격려와 실제사용의 인과 관계를 대중적 자기 인식 자기노출과 텔레프레즌스를 변수로 검증하였다. 그 결과, 대중적 자기인식과 자기노출은 인지된 유용성과 인지된 격려의 유의미한 요인으로 보여지고 인지된 유용성과 인지된 격려는 블로그의 실제사용에 유의미한 영향을 주는 것으로 보여졌다.

• Human Ecology Research
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• 제57권3호
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• pp.395-406
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• 2019

This study examined what meaning East Asian women showed in their costume history through a discourse of hair adornments such as wigs and that Gache was not just a luxury decoration. In addition, we examined Gache hair trends with Eonjeun-meori (braid wraps around the entire head) in the Joseon dynasty (Korea), Gigye(旗?) hair in the Quing dynasty (China) and Mage(?) hair in the Edo period (Japan) during the $18^{th}$ and $19^{th}$ centuries. The significance of the phenomenon of East Asian Gache culture in the $18^{th}$ and $19^{th}$ centuries was analyzed from the internal desires of women. The details are as follows. First, the magnification by the hair decoration was identified with self-authority and used as a sign to express self-respect or a desire for self-esteem. The extended Gache was an external body extension to raise self-authority and increase activeness. Second, self-satisfaction through showing off was associated with a women's search for identity. There was excessive consumption to boast status, wealth and femininity, but the mania continued because women obtained psychological satisfaction by feeling that their sacrifices for the Confucian order were compensated. Third, the frenzy of Gache was accepted as a way for women to resist social regulations and find themselves as main participants in social activities. Showing their appearance in East Asian Gache culture was a way of inner self-searching and a process for women to find themselves as a social entity.

• 한국조리학회지
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• 제22권6호
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• pp.33-51
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• 2016

The hotel industry needs to make the competitive advantage difficult to be imitated in order to remain sustainable in competitive business circumstances. Front-line employees' service-oriented citizenship behaviors(OCBs) can be such a strength from the perspective of organizational system. With an aim of investigating the antecedents of the hotel front-line employees' service-oriented OCBs, this study proposed a theoretical framework linking authentic leadership to service-oriented OCBs with goal commitment as a mediator. A total of 260 cases without missing values have been used for the final analysis and structural equation modeling (SEM) is employed using the SPSS and AMOS 7. It was first found that self-awareness and relational transparency of authentic leadership made a significant impact on their goal commitment while balanced processing and moral perspective failed to influence them. Second. goal commitment influenced all sub-factors of service-oriented OCBs. Third, moral perspective and relational transparency of authentic leadership significantly influenced service-oriented OCBs while self-awareness and relational transparency failed to make it. Finally, goal commitment significantly makes an intervening effect for the relationship between self-awareness & service-oriented OCBs and relational transparency & service-oriented OCBs but failed to intervene the other relationships. The results provide theoretical and practical implications regarding directions of leadership styles and HR management in the hotel industry and suggestions for the further extended studies.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
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• pp.12-14
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• 2005

In this paper, we propose a new architecture of Self-Organizing Fuzzy Polynomial Neural Networks(SOFPNN) by means of genetically optimized fuzzy polynomial neuron(FPN) and discuss its comprehensive design methodology involving mechanisms of genetic optimization, especially genetic algorithms(GAs). The conventional SOFPNNs hinges on an extended Group Method of Data Handling(GMDH) and exploits a fixed fuzzy inference type in each FPN of the SOFPNN as well as considers a fixed number of input nodes located in each layer. The design procedure applied in the construction of each layer of a SOFPNN deals with its structural optimization involving the selection of preferred nodes (or FPNs) with specific local characteristics (such as the number of input variables, the order of the polynomial of the consequent part of fuzzy rules, a collection of the specific subset of input variables, and the number of membership function) and addresses specific aspects of parametric optimization. Therefore, the proposed SOFPNN gives rise to a structurally optimized structure and comes with a substantial level of flexibility in comparison to the one we encounter in conventional SOFPNNs. To evaluate the performance of the genetically optimized SOFPNN, the model is experimented with using two time series data(gas furnace and chaotic time series).

• 한국통신학회논문지
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• 제21권11호
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• pp.2789-2800
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• 1996

Real time fractal coding for successive QCIF 144*176 luminance images has been implemented on a 50MHz IBM 486 personal computer. To satisfy the frame encoding speed and data compression ratio, following algorithms are adopted. In order to minimize encoding time, extension SAS being not searching of domain blocks is used. for reducing the bits per pixel, conventioal 4*4 range block is extended to 8*8 range block. and range block extension decrease quality of decoded image. For improvement quality of decoded image, the paper apply quad-tree partition mothod. In order to divide **8 range block, self-simiarity is compared 8*8 range block with spatial contractive transformed 8*8 domain block. According to self-simiarity, the block is partitioned and owing to block partition, increased encoding time is minimized. According to self-simiarity of 8*8 range block and spatial contractive transformed 8*8 domain block, number of fractal factor is varied. Simultaneously with minimizing the decrement of decoded image's quality, transmittion rate and encoding time is shorted. The results enable us to process the real-time fractal coding. For the claire test image, the average PSNR was 32.4dB, 0.12 bit rates and 33ms coding time per frame.