• Journal of Mechanical Science and Technology
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• 제20권9호
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• pp.1361-1370
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• 2006

An electronic beam mis-landing phenomenon on the RGB (red/green/blue) -fluorescent surface has been considered as one of serious problems to be solved in cathode-ray tube (CRT), which is generally caused by mechanical shock and vibration. In this work, structural design concepts on the major parts of the CRT, such as a frame, a shadow mask, and a spring, are studied to improve the mechanical shockproof character of a CRT by FEM-analyses and experimental approaches ; a frame is newly designed to have strength employing the double-corner-beads which reduces considerably the distortion of the frame and the shadow mask : the edge-bead of a shadow-mask is redesigned to maintain the wide curved surface of a shadow-mask after mechanical shock : finally, a spring supporting the frame and the shadow-mask is designed to have enough flexibility along drop-direction. As an example, a conventional type of a 15inch CRT was utilized to demonstrate the feasibility and usefulness of this work. Overall, some favorable information on the structural design of the CRT is achieved, and the mechanical shockproof character of a 15-inch CRT is improved in the degree of 3G $(1G=9.81m/s^2)$ as an average-value.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.219-219
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• 2012

The formation and thermal desorption behaviors of octanethiol (OT) SAMs on single crystalline Au (111) and polycrystalline Au, Ag, and Cu substrates were examined by X-ray photoelectron microscopy (XPS), thermal desorption spectroscopy (TDS), and contact angle (CA) measurements. XPS and CA measurements revealed that the adsorption of octanethiol (OT) molecules on these metals led to the formation of chemisorbed self-assembled monolayers (SAMs). Three main desorption fragments for dioctyl disulfide (C8SSC8+, dimer), octanethiolate (C8S+), and octanethiol (C8SH+) were monitored using TDS to understand the effects of surface morphology and the nature of metal substrates on the thermal desorption behavior of alkanethiols. TDS measurements showed that a sharp dimer peak with a very strong intensity on single crystalline Au (111) surface was dominantly observed at 370 K, whereas a broad peak on the polycrystalline Au surface was observed at 405 K. On the other hand, desorption behaviors of octanethiolates and octanethiols were quite similar. We concluded that substrate morphology strongly affects the dimerization process of alkanethiolates on Au surfaces. We also found that desorption intensity of the dimer is in the order of Au＞＞Ag＞Cu, suggesting that the dimerization process occurs efficiently when the sulfur-metal bond has a more covalent character (Au) rather than an ionic character (Ag and Cu).

• 인지과학
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• 제1권1호
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• pp.77-102
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• 1989

This paper reports on the development of a recognition system for Korean character,numbers and punctuation marks by syntactic approach after extracting a character or punctuation mark from a page of text.First,using the projection profile(Masudaet.al.1985,Pavlidin 1981)method, we segment a page into different regions of column or row major and then extracts lines of characters from it.Considering the height,width and connectivity of character block,we proceed to extract syllables from the extracted lines.Basically we distinguish syables into six types of formal pattern(남궁재찬 1982,이주근등 1981)following the research of lee and others,and the punctuation marks and numbers into two kinds of formal patterns,and discriminate the surface structure of the extracted syllables.By Index-Removal algorithm,we subdivide them into 44 kinds of basic korean subpattern and special characters (numbers,punctuation marks)and recognize them by syntactic method(이주근등 1981.)

• EDISON SW 활용 경진대회 논문집
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• 제6회(2017년)
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• pp.433-436
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• 2017

SIESTA를 이용하여 GaSe 단일층에서 금속 원자(Ga)를 전이금속 원자(W)로 치환하였을 때($W_{Ga}$)의 구조 deformation, 에너지 안정성, 전자구조와 자성을 확인하였다. 그 결과, 구조가 바뀌면서 평면에 수직한 방향으로 구조 변형이 나타났고, $W_{Ga}$에서 W의 NN는 Se이 되었다. Clean surface만큼 $W_{Ga}$도 안정된 구조임을 알 수 있었다. $W_{Ga}$에서 W에 의한 defect states가 up, down 6개씩 split되어 나타났으며, ${\Gamma}$ point에서 degenerated 경향을 보였다. 또한 W에 의한 magnetic moment는 $1{\mu}_B$인 것을 확인하였다. Defect states는 degenerated $d_{yz}$, $d_{zx}$ orbital character, degenerated $d_{xy}$, $dx^2-y^2$ orbital character, defect states는 $d_z{^2}$ orbital character을 띠는 것으로 나뉘었고, 이에 따라 에너지가 함께 높아졌다.

• 폴리머
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• 제39권1호
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• pp.99-106
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• 2015

나노케냐프 섬유가 포함된 셀룰로스 섬유를 알카리(NaOH)로 처리 후 PP 수지에 첨가하여 물성에 미치는 영향에 대하여 조사하였다. 알카리를 섬유에 처리한 효과로는 M.I., 신장율, 충격강도가 증가하는 반면 인장강도, 휨모듈러스, 열변형온도가 처리하지 않은 섬유에 비해 감소하였다. 알카리를 나노섬유에 처리하였을 때 섬유표면의 불순물과 화학물질을 제거하여 섬유표면의 특성을 변화시켜서 나노섬유와 PP 수지간의 계면간 접착력을 감소시키고 PP의 특성을 변화시키는 것으로 보인다.

• Geomechanics and Engineering
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• 제6권2호
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• pp.139-151
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• 2014

Mudstone is a very common rock that, when in contact with water, can exhibit considerable volume change and breakdown. This behavior of mudstone is frequently encountered in geotechnical engineering and has a considerable influence on infrastructure stability. This is particularly important in the present work, which focuses on mitigating the harmful properties of mudstone. The samples studied are of Permian Age mudstone from Shandong Province, China. Modification tests using organic silicone additive material were carried out. The mechanisms of physical properties modification of mudstone were comparatively studied using corresponding test methods, and the modification mechanism of organic silicone additive material acting on mudstone was analyzed. The following conclusions were drawn. The surface texture and characters of mudstone changed dramatically, surface character turns from hydrophilic to hydrophobic after organic silicone additive material modification. The changes in the surface character indicate a reduction in the water sensitivity of mudstone. After modification, the shape of porosity and fracture of mudstone changed unremarkable, and the total and free expansion ratios decreased obviously, whereas the strength increased markedly.

• 한국산업정보학회논문지
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• 제13권1호
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• pp.22-29
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• 2008

본 논문은 철강공장의 연주공정에서 만들어진 빌렛 소재의 관리를 위해 사용되는 소재 관리문자를 실시간으로 인식하기 위한 비전시스템 개발 결과에 대해 기술한다. 빌렛 재질의 단면에 마킹된 소재 관리문자는 소재가 다음 공정으로 이동하기 전에 공정상에서 실시간으로 인식된다. 문자인식용 비전시스템은 영상획득을 위한 카메라 시스템, 영상을 장거리로 고속 전송하기위한 영상전송 시스템, 기존 시스템과의 인터페이스를 위한 입 출력 장치 및 문자인식용 소프트웨어로 구성된다. 개발된 비전시스템을 실제 철강 선제공정에 설치하여 운용테스트를 실시했다. 테스트를 통해 시스템의 내구성과 신뢰성을 검증하고 최종적으로 문자 인식률을 검증했다. 개발된 시스템에 대해 문자인식 테스트 결과 약 98.6%의 높은 인식률을 가졌다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.444-449
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• 1996

The semiconductor, which is precision product, requires many inspection processes. The surface conditions of the semiconductor chip affect on the functions of the semiconductors. The defects of the chip surface are cracks or voids. As general inspection method requires many inspection procedure, the inspection system which searches immediately and precisely the defects of the semiconductor chip surface is required. We suggest the detection algorithm for inspecting the surface defects of the semiconductor surface. The proposed algorithm first regards the semiconductor surface as random texture and point spread function, and secondly presents the character of texture by linear estimation theorem. This paper assumes that the gray level of each pixel of an image is estimated from a weighted sum of gray levels of its neighbor pixels by linear estimation theorem. The weight coefficients are determined so that the mean square error is minimized. The obtained estimation window(two-dimensional estimation window) characterizes the surface texture of semiconductor and is used to discriminate the defects of semiconductor surface.

• 한국정밀공학회지
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• 제16권12호
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• pp.143-151
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• 1999

The shape of surface micro-crack is very irregular due to nonhomogeneous microstructure but is very important in respect to qualitative estimation of fatigue life. Fractal geomety can quantify the shape of surface mciro-crack. Fractal dimension is measured for surface micro-cracks with coast line and box counting method and estimates cycle ration in Al 2024-T3. The average fractal dimension $D_{favg}$ of surface micro-cracks has 3-parameter weibull distribution and location parameter is nearly constant but shape parameter decreases as cycle ration increases. The fractal dimension by coast line method is measured for individual surface micro-crack but the fractal dimension by box countin method is measured for all the surface micro-cracks under sampling area. Therefore, This paper shows fractal dimension $D_{fb}$ can predict cycle ratio $N/N_f$ more convenient than fractal dimension $D_{favg}$.

• Transactions on Electrical and Electronic Materials
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• 제8권6호
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• pp.265-267
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• 2007

The liquid crystal(LC) aligning capabilities of a nematic liquid crystal(NLC) on a homeotropic polyimide(PI) surface using a new ion-beam method were studied. Exposure ion-beam of $45^{\circ}$ incidence angle shows a good LC alignment of the NLC on the homeotropic PI surface. Also, on the homeotropic PI surface, the tilt angle of the NLC by exposure ion-beam of $45^{\circ}$ incidence angle had a tendency to decrease as increased ion-beam energy density. And, on the homeotropic PI surface, the alignment character of the NLC with respect to ion-beam energy was good at 1500 eV. And we achieved satisfactory result for EO character.