• 한국정밀공학회지
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• 제33권6호
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• pp.459-467
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• 2016

Using a line scan camera and a Galvano mirror, we constructed a high-speed line-scanning microscope that can generate 2D images ($8000{\times}8000pixels$) without any moving parts. The line scanner consists of a Galvano mirror and a cylindrical lens, which creates a line focus that sweeps over the sample. The measured resolutions in the x (perpendicular to line focus) and y (parallel to line focus) directions are both $2{\mu}m$, with a 2X scan lens and a 3X relay lens. This optical system is useful for measuring defects, such as spalling, chipping, delamination, etc., on the surface of carbon fiber reinforced plastic (CFRP) holes after machining in conjunction with adjustments in the angle of LED lighting. Defects on the inner wall of holes are measured by line confocal laser scanning. This confocal method will be useful for analyzing defects after CFRP machining and for fast 3D image reconstruction.

• Asia pacific journal of information systems
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• 제12권4호
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• pp.173-192
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• 2002

Internet-based on-line firms have focused on the development of new business models with an assumption that this new model would create their competitiveness. At the same time, off-line firms have opened new marketing channels on the internet in order to defend their position against on-line firms. Based on Porter's well-known generic strategy, this study compares between on-line firms and on-offline firms i) whether these two types of firms take different strategies among cost reduction, marketing differentiation, innovation differentiation, and focus and ii) how the performance of these two types of firms is affected by different strategy types. The result shows that on-offline firms prefer the strategy of marketing differentiation and innovative differentiation while the strategy of cost reduction and focus are taken without significant difference between online firms and on-offline firms. Also it is found that even though the strategy of marketing differentiation and innovation differentiation are more preferred by on-offline firms than on-line firms, these two strategy types have a significant influence on the on-line firms' performance while the focus strategy has a significant influence on the on-offline firms' performance. Other managerial implications are discussed.

• 한국정밀공학회지
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• 제14권10호
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• pp.119-126
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• 1997

The relationship between the applied stresses and the change of elastic wave velocity has been established based on the acoustoelasticity theory. The non-uniform stress field in a loaded specimen has been evaluated from the surface acoustic wave velocity measured by the line-focus acoustic microscopy with the acoustoelastic constants obtained form a calibration test. The evaluated stresses are in good agreement with the results calculated by finite element method.

• 말소리와 음성과학
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• 제2권3호
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• pp.11-22
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• 2010

The present study attempts to investigate declination in Korean and its relevant aspects to the length of utterance, the clause boundary, and focus. More specifically, I examine the relation of declination with the length of utterance, the declination reset at the clause boundary, and the effect of focus on declination. Results showed that the length of utterance had no relation with the first and last pitch values of the utterance but that they were consistent regardless of the length of utterance. However, the declination slope changed to be relatively gentle from the fourth accentual phrase to the end of the whole intonational phrase. There was a reset of declination in such a way that the first pitch in the second phrase was always lower than that of the first phrase, but the first pitch in the third phrase was not always lower than that of the second phrase when the whole utterance was composed of three phrases. Finally, the pitch values of the focusing words decreased as their position went back in a sentence. One declination line was formed in the case of focused utterance, but in the case of an utterance that contained a clause boundary, a new declination line was formed at the start of each new clause. These findings can be applied to developing a Korean speech synthesizer that contains natural prosody; they can be also utilized for teaching Korean prosody.

• 한국음향학회지
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• 제22권3호
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• pp.202-207
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• 2003

초음파트랜스듀서는 초점거리의 제어를 위해서 각 진동요소에 전기회로를 이용한 위상가중치를 부가하는 방식을 사용하고 있다. 그러나 이러한 방법은 진동요소가 증가함에 따라 전기회로가 더욱 복잡해진다. 본 연구에서는 바이몰프형 액츄에이터를 신호의 송수신을 하는PVDF의 뒷부분에 삽입하여 선집속형 트랜스듀서를 제작하였다. 이 트랜스듀서를 사용하여 액츄에이터에 인가되는 전압 변화에 의해 기계적으로 초점거리를 제어할 수 있었다. 이 방법을 사용한 결과 수중에서 선집속형 초음파 트랜스듀서의 초점거리를 곡률 반경의 10%범위까지 제어 가능함을 확인하였다.

• 한국정보과학회논문지:시스템및이론
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• 제37권2호
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• pp.110-125
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• 2010

본 논문은 이차원 영상으로부터 시각적으로 효과적인 정보를 제공할 수 있는 라인 드로잉 영상을 생성하는 방법을 제시한다. 본 방법은 기존의 단순한 에지 추출 방법과 달리 사람의 라인 드로잉 과정을 적용하여 직관적이면서 효과적인 결과를 생성하며, 크게 라인 추출, 라인 렌더링, 사용자 지시의 세단계로 구성된다. 라인 추출 단계에서는 우도 함수를 이용하여 물체의 중요한 경계 부분을 효과적으로 예측함으로써 라인을 추출한다. 추출된 라인을 실제 렌더링하는 라인 렌더링 단계에서는, 중요한 라인과 세부 라인의 구분 및 초점의 정확도를 표현하기 위하여 라인의 특징 크기와 번짐 정도를 고려하고, 이를 다양한 스타일로 표현하기 위해 텍스쳐 형태의 라인 영상을 적용한다. 마지막으로 사용자 지시 단계에서는 자동으로 생성된 라인의 모양이나 위치를 사용자 상호작용으로 수정할 수 있다. 이 때 사용자 입력에 대한 즉각적인 반응을 위해 라인 추출의 대부분의 과정이 GPU 상에서 구현된다. 제시된 방법의 결과로 사용자는 이차원 영상으로부터 중요한 부분과 초점이 맞는 부분의 표현 및 스타일을 원하는 대로 조절한 라인 드로잉을 얻을 수 있고, 또한 이를 자유롭게 수정할 수 있다.

• 한국분무공학회지
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• 제14권2호
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• pp.77-83
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• 2009

In this study, the effect of important parameters such as the pixel size and number of a CCD, the object distance, the wavelength of laser, and the particle diameter on the depth of focus in digital in-line particle holography were investigated. The depth of focus in several different cases was calculated using simulation holograms and detailed description of the depth of focus in digital particle holography was presented. The depth of focus is directly proportional to the object distance and the particle size. With the increase of the wavelength of laser, the depth of focus is decreased. The depth of focus is also inversely proportional to the pixel size and number of a CCD. Using the data of depth of focus from simulation holograms and a data-fitting software, we obtained the prediction equations of depth of focus for typical CCD cameras. Finally, the prediction equations of depth of focus in digital particle holography were verified by investigating real holograms of the calibration target in different cases and satisfied agreement between measured values and predicted values was confirmed.

• 한국음향학회지
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• 제20권1호
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• pp.62-67
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• 2001

직선집속 PVDF 초음파 트랜스듀서를 이용하여 누설탄성표면파 (Leaky Surface Acoustic Wave: LSAW)의 전파속도를 측정하고, 그 결과를 이론해석 결과와 비교하였다. 시료로는 등방성 재료인 구리, 알루미늄 및 용융석영, 이방성 재료인 Z-cut α/sup-/수정을 사용하였다. 측정방법으로는 초점면에 위치한 시료를 트랜스듀서 쪽으로 접근시켰을 때 LSAW가 트랜스듀서의 중심축을 통과한 후 시료표면에서 직접 반사되어오는 종파와 분리되어지는 현상을 이용하였다. 음속의 측정결과는 이론 해석결과와 오차 1％이내에서 잘 일치하였으며,α/sup-/수정의 (0,0,1)면에서는 LSAW 외에 의사누설탄성표면파 (Leaky Pseudo Surface Acoustic Wave : LPSAW)가 전형적인 6-fold 이방성을 가지고 전파됨을 알 수 있었다.

• 스마트미디어저널
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• 제1권4호
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• pp.27-34
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• 2012

In this paper, a novel text binarization is presented that can deal with some complex conditions, such as shadows, non-uniform illumination due to highlight or object projection, and messy backgrounds. To locate the target text region, a focus line is assumed to pass through a text region. Next, connected component analysis and stroke width estimation based on location information of the focus line is used to locate the bounding box of the text region, and each box of connected components. A series of classifications are applied to identify whether each CC(Connected component) is text or non-text. Also, a modified K-means clustering method based on an HCL color space is applied to reduce the color dimension. A text binarization procedure based on location of text component and seed color pixel is then used to generate the final result.

• 산업경영시스템학회지
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• 제27권1호
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• pp.38-46
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• 2004

To be successful in increasingly competitive Internet marketplace, it is essential to capture customer loyalty. This paper deals with an intelligent agent approach to incorporate customer's sensibility into an one-to-one recommendation service in on-line shopping mall. In this paper the focus of interest is on-line recommendation service algorithm for development of Human Sensibility based web agent system. The recommendation agent system composed of seven services including specialized algorithm. The on-line recommendation service algorithm use human sensibility ergonomics and on-line preference matching technologies to tailor to the customer the suggestion of goods and the description of store catalog. Customizing the system's behavior requires the parallel execution of several tasks during the interaction (e.g., identifying the customer's emotional preference and dynamically generating the pages of the store catalog). Most of the present shopping malls go through the catalog of goods, but the future shopping malls will have the form of intelligent shopping malls by applying the on-line recommendation service algorithm.