• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.398-398
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• 2007

The Liquid Crystal (LC) alignment uniformity is very important in LC devices. The alignment mechanism of LC molecules on a rubbed polyimide (PI) surface is very important for both LC fundamental research and application. So, Generally a rubbing method to align LC has been widely used to mass-produce LCD panels. But because rubbing method is contact method between rubbing fabric and indium-tin-oxide glass or flexible substrate, rubbing method has some defects, such as the electrode charges and the creation of contaminating particles. Thus we strongly recommend a non-contact alignment technique for getting rid of some defects of rubbing method. Most recently, the LC aligning capabilities achieved by ion-beam exposure on the organic and nonorganic thin film surface have been reported successfully. In this research, we studied the tilt angle generation and electro-optical performances for a NLC on homeotropic polyimide surfaces with ion-beam exposure. The LC aligning capabilities of a nematic liquid crystal (NLC) on a homeotropic PI surface using a new ion-beam method were studied. On the homeotropic PI surface, the tilt angle of the NLC by exposure ion-beam 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. And we achieved satisfactory result for EO character.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.521-527
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• 1997

Irregular shapes and growth behavior of surface micro-crack showed very complex and nonlinear propeties and many investigators have performed theoretical analysesand experiments on them to characterize fatigue strength. They had difficulties in estimating fatigue life due to random distribution, growth and coalescence of surface micro-cracks. The straightness of crack growth along intergranular and transgranular was prevented from irregular microstructure and precipitates. Euclid geometry can't quantify shape of surface micro-crack but ftractal geometry can. Therefore, it is suggested that average fractal dimension of surface micro-cracks is able to estimate fatigue life but fractal dimension of maximum surface micro-crack is not in Al 2024-T3 alloy.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.81-84
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• 1999

In this study, the influence of specific surface area of cement, substitution ratio of gypsum anhydrite on the physical properties of concrete were investigated by measurements of slump, air content and compressive strength. The results showed that reducing the specific surface area of cement under 3200$\textrm{cm}^2$/g and using 20% of gypsum anhydrite were desirable to prevent the decrease in workability and strength of concrete in summer season.

• Applied Microscopy
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• 제32권1호
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• pp.45-55
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• 2002

우리나라 환자의 안구 결막낭에 기생하는 동양안충은 T. callipaeda로 보고 되어 있다. 그러나 종 동정을 위한 분류학적 특징과 미세구조적 특징의 기술이 미비하여, 저자 등은 우리나라 환자의 결막낭에서 적출한 11마리의 동양안충을 주사전자현미경으로 관찰하고, T. callipaeda 의 충체 표피의 미세구조적 특징으로 다음과 같은 결과를 얻었다. T. callipaeda는 충체 표피가 각질줄무늬로 구성되어 있으며, 각질줄무늬는 충체의 구기부와 미부에는 약 $1.8{\mu}m$ 크기이며, 충체의 중앙 부위에는 $4.0{\sim}4.5{\mu}m$이다. 따라서 충체 표피 1mm에 각질줄무늬는 평균 400개로 구성되어 있었다. 자충의 충체 미단부에는 1쌍의 쌍선이 잘 발달되어 있으며, 웅충의 충체 미단부에는 쌍선이 감각유두와 유사한 형태로 관찰되었다. 충체의 구기부와 미단부에는 감각유두가 잘 발달되어 있으며, 구기부에는 구순부위에 쌍기와 감각유두가 다수 발달되어 있다. 웅충의 충체 미단부의 감각유두는 규칙적으로 분포하고 외부생식기를 중심으로 구기부 쪽으로 $7{\sim}8$쌍과 충체의 미단부로 5쌍이 발달하여 이들 감각유두의 분포가 T. callipaeda의 미세구조적 특징으로 확인되었다. 5쌍의 충체 미단부 감각유두는 분포 위치에 따라 anterior ventral postcloacal papillae, middle ventral postcloacal papillae, subventral postcloacal papillae 그리고 lateral papillae (phasmid)로 구성되어 있다. 따라서 동양안충은 주사전자현미경으로 각질줄무늬, 쌍기, 쌍선, 감각유두의 미세구조적 특징으로 종 동정이 가능할 것으로 생각된다.

• 한국멀티미디어학회논문지
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• 제19권11호
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• pp.1900-1908
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• 2016

Recent times have seen the introduction of modeling technologies using implicit surface and marching cubes algorithm in the field of computer graphics. Implicit surface modeling is used to express characters or fluid. This study presents a calculation method for the density of curve skeletal primitives using parametric curve and implements an implicit surface modeling tool by utilizing Maya API. Skeletal primitives can be assembled and utilized in character modeling using the implemented modeling tool. Results could be obtained more effectively compared to existing particle-based methods.

• 한국표면공학회지
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• 제32권3호
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• pp.344-350
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• 1999

The surface chemical structure of three kinds of polyethylene (PE): high density (HD) PE, low density (LD) PE and linear (L)-LDPE exposed to Ar and $O_2$ plasmas has been investigated using XPS. Oxygen was incorporated in a more increased amount for HDPE than for L-LDPE and LDPE. Ar plasma tended to incorporate more oxygen than $O_2$ plasma. The XPS valence band spectra for Ar plasma exhibited a clear peak assigned to $O_2$s character. By chemical derivatization method it was found that the amount of -COOH group at the surface was much greater than that of -OH group. The hydrophilic nature of plasma-treated PE increased in the order: LDPE

• Bulletin of the Korean Chemical Society
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• 제11권4호
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• pp.286-290
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• 1990

The surface enhanced Raman scatterings of Zn(Ⅱ) tetrakis (4-N-methyl pyridyl) porphyrins were studied in silver sol. Zn(Ⅱ) tetrakis (4-N-methyl pyridyl) porphyrin was found to be adsorbed on silver surface via flat-on geometry with some inhomogeneous distribution in the orientation of pyridyl groups. Both the selective enhancement of Raman modes depending on the mode character and the theoretical arguments of SERS are utilized to support the above conclusion. The surface induced substitution reaction of Mn(Ⅲ) tetrakis (4-N-methyl pyridyl) porphyrin chloride to Ag(Ⅱ) tetrakis (4-N-methyl pyridyl) porphyrin was detected via surface enhanced Raman spectrum.

• 한국전기전자재료학회논문지
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• 제27권10호
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• pp.623-629
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• 2014

For the semiconductor device safety from over current in the digital electronic circuit system must be surely designed that it's surface mount type micro fuse device. In this paper, We has analysed to the fusing character of micro fuse as a function changed thickness of thermosetting ink epoxy. To the change of thermosetting ink epoxy thickness with in production lot, in the electrically character (fusing test in the 2 multiple over current and 10 multiple over current, surface temperature test in the 1.25 multiple over current) of micro fuse has been tested. According to the electrically character result, changed thickness of thermosetting ink epoxy in designed micro fuse withheld direct effect in both end resistance changes. Also, because high thermal energy in the micro fuse test of over current was occurred to effect such as thermal runaway and explosion. Therefore, screen printing process in the design of micro fuse using thermosetting ink epoxy is very important for production quality improvement.

• 한국컴퓨터정보학회논문지
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• 제23권1호
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• pp.75-84
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• 2018

In this study, the researchers attempted to automate the process of painting the characters on the road surface, which is currently done by manual labor, by using the information and communication technology. Here are the descriptions of how we put in our efforts to achieve such a goal. First, we familiarized ourselves with the current regulations about painting letters or characters on the road, with reference to Road Mark Installation Management Manual of the National Police Agency. Regarding the graphemes, we adopted a new one using connection components, in Gothic print characters which was within the range of acceptance according to the aforementioned manual. We also made it possible for the automated program to recognize the graphemes by means of the feature dots of the isolated dots, end dots, 2-line gathering dots, and gathering dots of 3 lines or more. Regarding the database, we built graphemes database for plotting information, classified the characters by means of the arrangement information of the graphemes and the layers that the graphemes form within the characters, and last but not least, made the character shape information database for character plotting by using such data. We measured the layers and the arrangement information of the graphemes consisting the characters by using the information of: 1) the information of the position of the center of gravity, and 2) the information of the graphemes that was acquired through vertical exploration from the center of gravity in each grapheme. We identified and compared the group to which each character of the database belonged, and recognized the characters through the use of the information gathered using this method. We analyzed the input characters using the aforementioned analysis method and database, and then converted into plotting information. It was shown that the plotting was performed after the correction.

• Macromolecular Research
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• 제14권1호
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• pp.52-58
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• 2006

A novel fabrication of the patterned surfaces in the polymer films was demonstrated by using the self-organizing character of the block copolymers of polystyrene-b-oligothiophenes and polystyrene-b-aromatic amide dendron. Hexagonally arranged open pores with a micrometer-size were spontaneously formed by casting the polymer solutions under a moist air flow. The amphiphilic character of the block copolymers played the crucial role as a surfactant to stabilize the inverse emulsion of water in the organic solvent, and subsequently the aggregated structure of the hydrophilic oligothiophene or aromatic amide dendron segments remained on the interiors of the micropores. The chemical composition on the top of the surface of the microporous films was characterized by energy-filtering transmission electron microscopy (EFTEM) or a time-of-flight secondary ion mass spectrometer (ToF-SIMS). The characterizations clearly indicated that the patterned surfaces in the self-organized block copolymer films with the hexagonally ordered microporous structures were fabricated in a single step.