• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.211-219
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• 2018

This paper designs a nonlinear PI-type controller for the robust control of a boost DC-DC converter using a particle swarm optimization (PSO) algorithm. Based on the common knowledge that the transient responses can be improved if the P and I gains increase when the transient error is big, a nonlinear PI-type control design method is developed. A design procedure to autotune the nonlinear P and I gains is given based on a PSO algorithm. The proposed nonlinear PI-type controller is implemented in real time on a Texas Instruments TMS320F28335 floating-point DSP. Simulation and experimental results are given to demonstrate the effectiveness and practicality of the proposed method.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.284-286
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• 1993

Software and hardware for cochlear implant system have been developed to create a speech signal processing system which, in real-time, extracts model parameter including formants, pitch, amplitude information. The system is based on the Texas Instruments TMS320 family. In hardware, computer interface has been desisted and implemented that allows presentation of biphasic pulse stimuli to patients with the hearing handicapped. The host computer sends a stream of bytes to the parallel port. Upon receipt of the data the interface generates the appropriate burst sequence that is delivered to the patient's external transmitter coil. The coded information is interpreted by the Nucleus-22 internal receiver that delivers the pulse to the specified electrodes at the specified amplitude and pulse width.

• MALSORI
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• no.33_34
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• pp.137-148
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• 1997

이 논문의 목적은 표준한국어의 강세유형을 Hayes(1995)의 Metrical Stress Theory의 틀내에서 형식화하는 것이다. 표준한국어의 강세 유형에 대해서는 여러 가지 설이 있으나 이 논문에서는 이 현복(1989)의 기술을 분석대상으로 삼았다. 이 현복(1989)에 따르면 한국어의 강세는 단어의 첫 두 음절 중 하나에 온다. 첫 음절이 중음절이면 그 음절에 강세가 오며 그 외의 경우에는 두번째 음절에 강세가 온다. 이와 같은 강세 규칙을 footing의 존재 여부, footing의 반복성, 그리고 footing의 방향을 고려하여 살펴보면 표준한국어의 강세 유형은 "왼쪽 끝에서 시작되는 비반복 footing을 보이는 iamb"이다.

• Tribology and Lubricants
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• v.4 no.2
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• pp.68-75
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• 1988

서로 다른 그루브 깊이를 갖는 circumferentially-grooved 씨일들의 동특성 계수 및 누설량에 대한 실험결과를 분석하였다. 실험된 결과를 분석해 보면, 그루브 깊이가 증가함에 따라, 누설량이 서서히 증가함을 알수 있다. Smooth 씨일 및 damper 씨일과 비교할때, smooth 씨일은 최대의 direct stiffness를 가지며, 평균 씨일 간극의 증가함에 따라 direct stiffness가 감소한다. Effective damping에 있어서, circumferentially-grooved 씨일은 최소의 값을 가지는 반면, 누설량은 가장 적다. 이론과의 실험치 비교는 일반적으로 만족할만한 결과를 보인다.

• Journal of Fashion Business
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• v.20 no.6
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• pp.32-51
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• 2016

KakaoTalk has become a reputed mobile social network and an inseparable part of people's lives by leading the mobile industry in South Korea. However, there is a lack of studies in academia regarding perception of the consumers and assessment toward the mobile marketing and services by KakaoTalk. Based on the theoretical orientation of Elaboration Likelihood Model (ELM: Petty & Cacioppo, 1986) and electronic service quality (E-S-QUAL: Parasuraman, Zeithaml, & Malhotra, 2005), this study investigates the effects of information sources (Charles & Richard, 1988), and examines the consumer perception toward the service quality of KakaoTalk. A total of 209 responses were collected, using a self-administered survey in Seoul and Gyeonggi province, South Korea from March 2015 to June 2015. A seven-point Likert scale survey was developed to measure the information sources (i.e., argument quality, post popularity, and post attractiveness), electronic service quality (i.e., efficiency, fulfillment, privacy, and system availability), attitude (i.e., usefulness, preference, and overall attitude), and behavioral intention (i.e., like intention, share intention, and purchase intention). This study reveals a consensus that an online environment is different from the traditional retail context in terms of information source and service quality. Specifically, the results indicate that argument quality greatly impacts the attitudes of the individuals and their behavioral intention toward mobile shopping via social media channel. The most powerful factor among E-S-QUAL is "efficiency." This dimension of service quality influences the customer perception of usefulness and preference as well as share and like intention toward mobile shopping on KakaoTalk.

• Journal of the Korean Institute of Educational Facilities
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• v.24 no.6
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• pp.3-10
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• 2017

The efforts for sustainable development in building construction is widely applied by global organizations, governments, etc. However, according to the researchers, if the green rating systems on the building, it is reported that construction costs and durations are increased compared to conventional buildings. In this respect, the objective of this study is to identify the construction costs between LEED and non-LEED buildings. The scope of this study is limited in 21 university buildings of Canada. The methodology is as follows: First, the data of LEED and non-LEED buildings are collected in every university building. Second, the average construction costs per square meter is collected and normality check is conducted. Third, to identify statistical significance, the difference of average construction costs is analyzed by using T-test. As a result, it is concluded that the construction costs of LEED buildings are increased by approximately 3.8% more than non-LEED buildings. In the future, the results of this study can be applied to analyzing the additional costs according to the LEED grade in educational buildings.

• Journal of the Korean Institute of Educational Facilities
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• v.25 no.1
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• pp.3-12
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• 2018

Educational facilities are more uncertain about maintenance costs due to their comprehensive and long life-cycle compared to commercial buildings. In addition, maintenance of the existing post management system can not maintain the original function of education facilities continuously and economically. In order to overcome this problem, it is necessary to analyze the repair and replacement cost for the uncertainty factor in maintenance. This study propose a model to determine repair and maintenance cost and cycle of educational facility based on probabilistic estimation concept. For the analysis, Monte Carlo simulation, a probabilistic analysis method, was applied based on the repair and maintenance history data of the educational facilities in Florida. The results of this study can be used as a guideline for quantitative facility management and facility management research.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.389-392
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• 2005

In the maskless photolithography based on the Digital Micromirror Device (DMD) by Texas Instruments Inc. (TI), the micromirror array works as a virtual photomask to write patterns directly onto Flat Panel Display (FPD) at high speed with low cost. However, it is neither simple to generate region-based patterns for the micromirror array nor easy to deliver sequences of patterns for the micromirror controller. Moreover, the quality of lithography yields the precise synchronization between generating sequence of patterns and irradiation rate off micromirrors. In this study, the region-based pattern generating system for maskless photolithography is devised. To verify salient features of devised functionalities, the prototype system is implemented and the system is evaluated with actual DMD based photolithography. The results show that proposed pattern generating method is proper and reliable. Moreover, the devised region-based pattern generating system is robust and precise enough to handle any possible user specified mandate and to achieve the quality of photolithography required by FPD manufacturer.

• Communications for Statistical Applications and Methods
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• v.16 no.1
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• pp.169-183
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• 2009

The simplicity and wide application of Greenberg et al. (1971) prompts to propose a set of alternative estimators of population total for multi-character surveys that elicit simultaneous information on many. sensitive study variables. The proposed estimators take into account the already known rough value of the correlation coefficient between Y(the characteristic under study) and p(the measure of size). These estimators are biased, but it is expected that the extent of bias will be smaller, since the proposed estimators are suitable for situations in between those optimum for the usual estimators and the estimators based on multi-characters for no correlation. The relative efficiency of the proposed estimators has been studied under a super population model through empirical study. It has been found through simulation study that a choice of an unrelated variable in the Greenberg et al. (1971) model could be made based on its correlation with the auxiliary variable used at estimation stage in multi-character surveys.

• Journal of The Korean Astronomical Society
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• v.44 no.4
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• pp.115-123
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• 2011

To perform imaging observations of optically red objects such as high redshift quasars and brown dwarfs, the Center for the Exploration of the Origin of the Universe (CEOU) recently developed an optical CCD camera, Camera for QUasars in EArly uNiverse (CQUEAN), which is sensitive at 0.7-1.1 ${\mu}m$. To enable observations with long exposures, we develop an auto-guiding system for CQUEAN. This system consists of an off-axis mirror, a baffle, a CCD camera, a motor and a differential decelerator. To increase the number of available guiding stars, we design a rotating mechanism for the off-axis guiding camera. The guiding field can be scanned along the 10 arcmin ring offset from the optical axis of the telescope. Combined with the auto-guiding software of the McDonald Observatory, we confirm that a stable image can be obtained with an exposure time as long as 1200 seconds.