• 한국의류학회지
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• 제27권5호
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• pp.523-523
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• 2003

The change of interactions of anionic surfactants, sodium dodecyl sulfate(SDS) and sodium tetradecyl sulfate(575) in the presence of electrolytes, to the chitosan-based polyelectrolyte(sol＇n and gel phase) were studied. The chitosan gel used in this study were crosslinked with epichlorohydrin(ECH). Binding isotherms were determined by potentiometric technique using a surfactant ion selective solid-state electrode and the results were represented by using the sequence generating function(SGF) method. The results of binding isotherm were shown comparatively high cooperativity. The addition of electrolytes in the chitosan/SDS system resulted in a shift of the binding to higher free surfactant concentration because of screen effect by the electrolytes. Degree of binding of chitosan gel was higher than that of chitosan sol＇n. And also a conformational phase transition of the chitosan gel in the presence of electrolytes has been investigated.

• 한국의류학회지
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• 제27권5호
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• pp.524-532
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• 2003

The change of interactions of anionic surfactants, sodium dodecyl sulfate(SDS) and sodium tetradecyl sulfate(575) in the presence of electrolytes, to the chitosan-based polyelectrolyte(sol＇n and gel phase) were studied. The chitosan gel used in this study were crosslinked with epichlorohydrin(ECH). Binding isotherms were determined by potentiometric technique using a surfactant ion selective solid-state electrode and the results were represented by using the sequence generating function(SGF) method. The results of binding isotherm were shown comparatively high cooperativity. The addition of electrolytes in the chitosan/SDS system resulted in a shift of the binding to higher free surfactant concentration because of screen effect by the electrolytes. Degree of binding of chitosan gel was higher than that of chitosan sol＇n. And also a conformational phase transition of the chitosan gel in the presence of electrolytes has been investigated.

• Journal of the Optical Society of Korea
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• 제8권4호
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• pp.168-173
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• 2004

Brillouin scattering-based fiber optic sensors are useful to measure strain or temperature in a distributed manner. Since the Brillouin frequency of an optical fiber depends on both the strain and temperature, it is very important to know whether the Brillouin frequency shift is caused by the strain change or temperature change. This article presents a temperature compensation technique of a Brillouin scattering-based fiber optic strain sensor. Both the changes of the Brillouin frequency and the Brillouin gain power is observed for the temperature compensation using a BOTDA sensor system. Experimental results showed that the temperature compensated strain values were highly consistent with actual strain values.

• 한국광학회:학술대회논문집
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• 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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• pp.113-118
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• 1989

By using the single mode optical fiber, we fabricated Fiber-optic Fabry-Perot interferometer (FFPI). The change over a wide range in the optical path length of a FFPI is observed. The temporal movement of the interference fringes by external condition to P.Z. T) is converted to circular motion on an oscilloscope display and then recorded with a micro-computer. The two output voltages of the D/A converters are applied to X and Y terminals of oscilloscope to display circular motion on oscilloscope. Thus the direction of phase shift can be determined with observing the direction of circular motion. The variation of the optical length can be measured by calculating the angle of spot of circle with an accuracy of λ/90 wave length due to variation of temperature in this system 2.7x10-4$^{\circ}C$.

• 한국정밀공학회지
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• 제10권1호
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• pp.77-88
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• 1993

In this paper, we propose a stereo vision system to solve correspondence problem with large disparity and sudden change in environment which result from small distance between camera and working objects. First of all, a specific feature is divided by predfined elementary feature. And then these are combined to obtain coded data for solving correspondence problem. We use Neural Network to extract elementary features from specific feature and to have adaptability to noise and some change of the shape. Fourier transformation and Log-polar mapping are used for obtaining appropriate Neural Network input data which has a shift, scale, and rotation invariability. Finally, we use associative memory to obtain coded data of the specific feature from the combination of elementary features. In spite of specific feature with some variation in shapes, we could obtain satisfactory 3-dimensional data from corresponded codes.

• International Journal of Naval Architecture and Ocean Engineering
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• 제3권3호
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• pp.181-192
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• 2011

Recently, the speed of change related with enterprise management is getting faster than ever owing to the competition among companies, technique diffusion, shortening of product lifecycle, excessive supply of market. For the example, the compliance condition (such as delivery date, product quality, etc.) from the ship owner is getting complicated and the needs for the new product such as FPSO, FSRU are coming to fore. This paradigm shift emphasize the rapid response rather than the competitive price, flexibility and agility rather than effective and optimal perspective for the domestic shipbuilding company. So, domestic shipbuilding companies have to secure agile and flexible ship production environment that could respond change of market and requirements of customers in order to continue a competitive edge in the world market. In this paper, I'm going to define a standard shipbuilding production management system by investigating the environment of domestic major shipbuilding companies. Also, I'm going to propose a unified ship production management and system for the operation of unified management through detail analysis of the activities and the data flow of ship production management. And, the system functions for the strategic approach of ship production management are investigated through the business administration tools such as performance pyramid, VDT and BSC. Lastly, the research of applying strategic KPI to the digital shipyard as virtual execution platform is conducted.

• 말소리와 음성과학
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• 제11권4호
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• pp.35-43
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• 2019

This study examines the voice onset times (VOTs) of Korean stops produced by Korean learners of English with high language proficiency and long L2 exposure (i.e., Korean-English bilinguals) to assess whether the VOTs of their lax and aspirated stops are merging and, if so, which types of stops are being changed. Thirteen Korean speakers (six female and seven male) who had studied in the USA for more than three to ten years participated. The results show that the speakers in this study with long L2 exposure are participating in the VOT merger, in which VOTs for aspirated stops are reduced while those for lax stops are increased. In other words, change in VOT affects not only aspirated stops but also lax stops. The results indicate that L1 phonetic drift may not be primarily affected by the amount of L2 exposure, and language contact may not be the primary factor triggering a sound change in the Korean stop system. Further study is necessary focusing on the phonetic shift of the "lax" category because it may play a pivotal role in a tonogenetic-like sound change in present-day Korean.

• 한국정보통신학회논문지
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• 제11권9호
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• pp.1734-1741
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• 2007

본 논문에서는 정규화 된 부반송파 간격과 확산 이득이 동일하고 각 부반송파의 직접 확산 코드가 직교하도록 하는 직교 MC DS-CDMA 시스템에 비트 동기와 위상 동기가 요구되지 않는 Hybrid SC/MRC-2/4 방식을 적용하였다. 다중 반송파 전송이 사용되는 광대역 무선 시스템에서는 가장 높은 부반송파 주파수와 가장 낮은 부반송파 주파수 차이 때문에 발생하는 도플러 주파수 천이가 발생하고 이로 인한 위상 에러율 보상하기 위하여 전체 시스템에 맞는 PLL이득 값을 조절하여 완전 동기 된 수신 신호가 되도록 직교 MC DS-CDMA시스템을 분석하였다. 분석 결과, PLL이득 값을 증가시킴에 따라 완전 동기 된 경우에 근접함을 알 수 있지만 일정 값 이상에서는 그 간격의 변화가 매우 작아짐을 알 수 있다. 따라서 시스템에 맞는 적절한 PLL이득 값을 선택함으로써 Hybrid SC/MRC 방식이 적용된 직교 MC DS-CDMA시스템을 설계할 수 있을 것이다.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.695-699
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• 2000

The success of quality management is depend on will of TOP and flexibility in the field. Moreover, the level of standardization of the company is the important index for activation of quality management and establishment of $\boxDr$Prevention Manufacturing Systems$\boxUl$. Six sigma, which is highlighted recently, totally certify the paradigm shift from Management by AFTER to management by BEFORE and regard as a scientific, statistic expression of management activity for understanding customer's needs correctly. So in this paper I introduce the Samsung Corning quality management system and all. sorts of related systems for process improvement receiving positively change of

• Journal of the Optical Society of Korea
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• 제15권1호
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• pp.22-29
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• 2011

We analyze aberrations in an optical laser printer system in order to know how to determine an allowable non-uniformity of the movement of a light spot, how to determine allowed variation of spot sizes, and how to minimize the influence of these deviations on technological errors. In this paper, the correction and the tolerance of distortion are analyzed by using the concept of zonal and global distortions. The tolerance of field curvature is also obtained from Gaussian beam properties. In order to reduce the change of the entrance pupil position and to make a more compact laser printer system the minimum size of the rotator is exactly derived from the geometry with the introduction of the shift angle of the input beam.