• Journal of Korea Foundry Society
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• v.18 no.4
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• pp.389-397
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• 1998

회주철 모재의 표면에 감압 플라즈마 용사법으로 실리콘 분말을 피복시킨 후 $CO_2$ 레이저를 이용하는 표면 합금화로 고온 내스케일성이 향상된 표면 개질층을 제조하였다. 실리콘의 표면 합금층에는 응집상의 흑연(chunky graphite)이 $Fe_5Si_3$로 구성된 망상의 화합물 기지속에 정출하는 조직특성을 보였다. 대기 분위기에서 18.0ks동안 열중량측정(TG)한 결과 실리콘 표면 합금층의 무게 증가율은 회주철 모재에 비하여 923K에서는 약 1/3, 1098K에서는 약 1/10을 나타내었다. 그리고 1098K에서 18.0ks동안 유지시킨 주철모재 시편에서 원래의 모재표면을 기준으로 다공성의 외부스케일과 편상흑연을 따라 생성된 내부스케일로 구성된 두께 $60{\sim}70\;{\mu}m$의 두꺼운 산화스케일이 생성되었으나, 실리콘의 표면 합금층에서는 두께 $3{\sim}5\;{\mu}m$의 치밀한 외부 산화스케일만이 생성되었다. 실리콘 합금층의 단면 미소경도값은 MHV $300{\sim}1100$으로 그 변동폭이 심하였으나, 진공분위기에서 열처리(1223K, 18.0ks)한 경우 미소경도값의 편차는 MHV $300{\sim}500$으로 개선되었다.

• Journal of the Institute of Convergence Signal Processing
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• v.11 no.3
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• pp.183-188
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• 2010

In this paper we propose a detection method of the medial axis of the continuous stripes on the LoG scale-space. Our method detects the medial axis of continuous stripes iteratively by varying the scale of LoG operator. Small-scale LoG operator detects two +/- pole pairs centered on the edge positions of stripe by the zero-crossing detection. The more increase the scale of LoG scale-space, the more close two poles to the medial axis of stripe. The medial axis of continuous stripe is the position where two poles is overlapped. The proposed method detected robustly the medial axis of continuous stripes stronger than the thinning methods used to binary image.

• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.41-46
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• 2021

The method of the edge detection algorithm based on grayscale mathematical morphology has the advantage that image noise can be removed and processed in parallel, and the operation speed is fast. However, the method of detecting the edge of an image using a single structural scale element may be affected by image information. The characteristics of grayscale morphology may be limited to the edge information result of the operation result by repeatedly performing expansion, erosion, opening, and containment operations by repeating structural elements. In this paper, we propose an edge detection algorithm that applies a structural element with strong directionality to noise and then applies weighted entropy to each pixel information in the element. The result of applying the multi-scale structural element applied to the image and the result of applying the directional weighted entropy were compared and analyzed, and the simulation result showed that the proposed algorithm is superior in edge detection.

• Journal of the Economic Geographical Society of Korea
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• v.24 no.1
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• pp.52-75
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• 2021

The current Korean labour movement is at an impasse that is partly sustained by the idea of "strong" transnational corporations (TNCs) versus "weak" labour, and this perception is based on the "global-local dichotomy," wherein TNCs are depicted as abstract and structured entities operating at the global scale and workers are represented as having a concrete and weak presence within the local sphere. As an alternative perspective to break this "global" capital vs. "local" labour dichotomy, I focus on labour geography, which assumes that labour is not simply a factor of production but a sentient spatial actor that (un-)intentionally produces the landscape of capitalism. Borrowing insights from the multi-scalar perspective, this paper aims to understand the actual methods in which workers utilize spatial strategies through an empirical case study of the Nestlé Korea labour union strike in 2003. Based on this case study, this paper claims that workers are both capable of employing coordinated multi-scalar practices and can be more influential to the economic geographies of TNCs. Additionally, it suggests that workers' scalar practices are actually more complicated and multi-directional as a result of their complex and dynamic interactions with political, economic and cultural forces and actors at diverse geographical scales.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1378_1380
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• 2009

절연파괴 강도에대한 특성분석을 위해 와이블 plot을 이용하였다. ENMMC에서 실란처리와 미처리특성에서 실란처리된 결과 형상파라미터가 상대적으로 높은 값을 나타내었다. 이는 절연파괴결과가 균질함을 분명하게 나타낸 결과이다. 또한 스케일파리미터에서도 처리된 결과가 상대적으로 높은 결과를 보이고 있다. 나노입자 충진함량에 대한 효과에서도 체적비로 6.2vol%가 24.87vol%보다 월등하게 높은 형상파리미터와 스케일 파리미터를 나타내었다. 현장에서는 B10의 수명이 누적확률(63.2%)보다 오히려 유효한 평가자료 라고 사료된다. 역시 실란처리 된 결과가 미처리된 것에 비하여 그리고 나노입자 충진함량이 적을수록 높은 결과를 나타내었다. 이로서 중전기기 산업절연재료로서 향후 전망을 크게 할 것으로 본다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.07a
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• pp.352-355
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• 2012

최근 인터넷 및 디지털 방송 서비스 환경 변화에 따라 사용자에게 제공되는 디지털 콘텐츠가 기하급수적으로 증가하게 되었고, 스마트 TV, 스마트 패드, 스마트폰 등 디지털 콘텐츠를 이용할 수 있는 기기들이 다양화 되어지고 있다. 또한, 사용자가 디지털 콘텐츠를 수집하는 경로와 이용하는 환경도 다양해지고 있다. 하지만, 현재 사용자가 제공되어 지고 있는 디지털 콘텐츠들은 특정 단말 및 사용환경에 종속된 형태로 제작되어 서비스되어지고 있으며, 다양한 성능을 가지는 단말들의 특성과 디지털 콘텐츠를 이용하는 사용자의 사용환경에 최적화된 서비스를 제공하지 못하고 있는 실정이다. 이에, 본 논문에서는 단말의 특성 및 사용자 사용환경에 최적화된 서비스를 제공할 수 있는 스케일러블 데이터 서비스를 제공하기 위한 프레임워크 기술과 스케일러블 데이터 서비스를 기술하기 위한 언어인 SADL(Scalable Application Descript Language)를 소개하고, 사용자가 사용하는 단말 특성과 사용환경에 최적화된 서비스를 제공하기 위한 SADL기반 콘텐츠를 저작할 수 있는 저작도구를 제안한다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.127-130
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• 2011

본 연구에서는 나노입자와 고분자 기지 간에 공유결합을 형성시킨 나노복합재의 계면특성과 탄성계수에서 나타나는 크기효과를 고려하기 위해 분자동역학과 미시역학모델을 순차적으로 연계하는 멀티스케일 해석모델을 제안하였다. 나노입자의 체적분율이 동일한 5개의 나노복합재 셀에 대해, 입자의 표면 원자와 고분자 기지 간에 탄소로 구성된 공유결합을 생성시킨 후 분자동 역학 전산모사를 통해 탄성계수를 예측하였고, 공유결합이 존재하지 않는 나노복합재의 탄성계수와 이를 비교하여 계면의 물성증가와 탄성계수에서 나타나는 입자의 크기효과를 규명하였다. 향상된 계면의 특성을 연속체 해석 모델에서 고려하기 위해 분자동역학 해석결과와 미시역학 모델을 연계하는 순차적 브리징 기법을 적용하였고, 이로부터 계산된 계면의 물성의 타당성을 유한요소 해석을 통해 검증하였다. 그 결과 입자와 기지 간 공유결합을 통해 나노복합재가 보다 넓은 범위에 걸친 크기효과를 나타냈으며, 제안된 브리징 모델을 통해서 물리적으로 타당한 계면의 탄성계수 값을 계산할 수 있었다.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.2
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• pp.328-339
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• 2010

This study was conducted to develop a service quality measurement scale suitable for the fast food restaurant segment. After reviewing the relevant literature, it was decided that the current service quality measurement scales (SERVQUAL, SERVPERF, DINESERV) are not appropriate for the fast food restaurant segment. Based on Cronin & Taylor's (1994) argument, perceived service quality is a form of attitude that represents a long-term overall evaluation of the company. Therefore, this study selected SERVPERF items for the initial pool of service quality items. Through a systematic scale development process, the SERVPERF instrument was then refined and a new concise scale was produced. Specifically, a focus group discussion with a group of patrons who are very familiar with fast food restaurants was conducted and the new service quality measure was refined so that it would be more realistic and closely describe service operation in the fast food industry. Moreover, the data collected from 112 college students who visit fast food restaurants frequently were used to statistically evaluate each of the items again via EFA (Exploratory Factor Analysis) and three sub-dimensions were derived: (1) responsiveness, (2) tangibles, and (3) reliability. Additionally, the data collected from 179 fast food restaurant consumers was used to conduct CFA (Confirmatory Factor Analysis). During this process, the convergent validity, discriminant validity, and internal consistency were double-checked. Overall, the newly developed scale achieved validity and reliability on a theoretical and statistical basis. Possible interpretations and managerial implications are also suggested.

• Journal of the Korean earth science society
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• v.27 no.3
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• pp.313-327
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• 2006

This study investigated the geochernical characteristics of Mn scale formed in groundwater wells at the Damyang area. The composition of Mn scale consists mainly of MnO and $SiO_2$. The content of Mn ranges from56.61wt.% to 68.69wt.%, and $SiO_2$ content ranges from 1.56wt.% to 10.45wt.%. The contents of Mo and Ba in Mn scale increased with increased depth; whereas, the content of Zn and Pb decreased with increased depth. Birnessite, quartz and feldspars were identified in Mn scales using x-ray powder diffraction studies. The IR absorption bands for Mn scales show major absorption band due to OH stretching, adsorbed molecular water, and birnessite stretching, respectively. In the SEM and EDS analysis, the Mn scale consists of botryoidal, spherical, spherulite, and empty straw structure. Those structure may be precipitated simply due to oversaturation with concentrated Mn content or may be formed through biogenic precipitation by Lepthothrix discophora. Under microanalysis using EDS on those structure surface of Mn scales, the Mn atomic percent range from 28 to 44, and such elements revealed the presence of Si, K, Na, Ca, Cl, Cu, Zn, and Ba.

• Journal of the Korean GEO-environmental Society
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• v.12 no.11
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• pp.51-57
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• 2011

The calcium hydroxide($Ca(OH)_{2}$) which is flowed into the deteriorated tunnel by groundwater is reacted with carbon dioxide($CO_{2}$) and the vehicle's exhaust gas ($SO_{3}$). So its by-products are precipitated at the drainage pipe and these cause the drainage clogging. Most by-products are composed of $CaCO_{3}$ with calcite from a chemical experiment. The purpose of this study is mainly focused on comparison of attachment on each material of drainage pipe (teflon-coated steel pipe, silicon-Oil coated pipe, acrylic pipe and PVC pipe). The test was progressed to disembogue the CaO aqueous solution and tunnel outflow into each of the pipes. The experimental results show that the most produced scale pipe is PVC material and the followings are Acrylic pipe, Silicon-Oil coating pipe and Teflon coating pipe. But the long-term test results showed that teflon-coated steel pipe had a problem with durability because soil which was contained in the tunnel outflow occurred detachment of coating and corrosion of the steel pipe.