• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
• /
• pp.90-93
• /
• 1987

Phase conjugate wavefront generation via real-time holography in degenerate four-wave mixing experiments in photo-refractive crystal $Bi_{12}$ Si $O_{20}$ is presented. Depending on the respective values of applied field $E_o$ and fringe spacing, drift or diffusion of the photecarriers dominates the space-charge buildup and affects the Phasa- Conjugate Wavefront intensity. The experimental results for wavefront reflectivity as a function of the intensity ratio of the writing beams agree with the theoretical predictions.

• 한국정밀공학회지
• /
• 제21권5호
• /
• pp.122-130
• /
• 2004

In a high-speed and wide operating field optical disk drive, the vibration problem is one of the most important factors to be considered for reliable performance. And a disk misaligned with axis of rotation is a major source of vibration in optical disk drive. Furthermore, this vibration disturbance of the disk spindle system causes failure in the reading and writing process. So to solve this vibration problem, the vibration absorber using rubber mount has been introduced in recent years. In this paper, we have analyzed the simple optical disk drive model with dynamic vibration absorber through dynamic analysis of 12-dof by Recurdyn program and obtained optimal mass and frequency ratios of dynamic vibration absorber of dynamic vibration absorber and the optimal frequency ratio.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2005년도 추계학술대회 논문집
• /
• pp.149-153
• /
• 2005

The electron beam machining provides very high resolution up to nanometer scale, hence the E-beam writing technology is rapidly growing in MEMS and nano-engineering areas. In the optical column of the e-beam writer, there are several lenses condensing and focusing electron beams from electron gun with fringing magnetic fields. The polepieces of these lenses are usually made with high purity iron which is hard to fabricate and very expensive. In this paper, the possibility of using polepiece of object lens composed with pure iron and low carbon steel was examined to reduce cost. The magnetic field at object lens was calculated with finite element method, and practical focusing qualities of SEM pictures were observed comparing for the object lens polepieces with pure iron and two type of composed with low carbon steel.

• 한국정보통신학회논문지
• /
• 제11권9호
• /
• pp.1781-1785
• /
• 2007

본 논문에서는 스마트폰에서 사용 가능한 동적서명 인증기술의 사용자 인터페이스와 알고리즘을 제안하고, 제안된 시스템의 성능을 기술하였다. 개인 서명의 모양, 쓰는 속도, 기울기, 획수와 획순서 등의 정보를 활용함으로써 인증 여부를 결정하게 되며, 컴퓨터와 무선인터 넷이 발달하고 관련 산업이 급성장함에 따라서 폭 넓은 산업 분야에 활용될 것으로 기대된다.

• Advances in aircraft and spacecraft science
• /
• 제9권3호
• /
• pp.243-261
• /
• 2022

Broad writing on the examination of sandwich structures mirrors the significance of incorporating thermal loadings during their investigation stage. In the current work, an endeavor has been made to concentrate on sandwich FGM beams' bending behaving under thermal loadings utilizing shear deformation theory. Temperature-dependent material properties are used during the analysis. The formulation includes the transverse displacement field, which helps better predict the behavior of thick FGM beams. Three-different thermal profiles across the thickness of the beam are assumed during the analysis. The study has been carried out on both symmetric and unsymmetric sandwich FGM beams. It has been observed that the bending behavior of sandwich FGM beams is impacted by the temperature profile to which it is subjected. Power-law exponent and thickness of core also affect the behavior of the beam.

• 한국재료학회지
• /
• 제34권3호
• /
• pp.144-151
• /
• 2024

This work focuses on the fabrication of excellent magnetic structures for trapping breast cancer cells. Micromagnetic structures were patterned for trapping cancer cells by depositing 30 nm of permalloy on a silicon substrate. These structures were designed and fabricated using two fabrication techniques: electron beam lithography and laser direct writing. Two types of magnetic structures, rectangular wire and zig-zagged wire, were created on a silicon substrate. The length of each rectangular wire and each straight line of zig-zagged wire was 150 ㎛ with a range of widths from 1 to 15 ㎛ for rectangular and 1, 5, 10 and 15 ㎛ for zigzag, respectively. The magnetic structures showed good responses to the applied magnetic field despite adding layers of silicon nitride and polyethylene glycol. The results showed that Si + Si₃N₄ + PEG exhibited the best adhesion of cells to the surface, followed by Si + Py + Si₃N₄ + PEG. concentration of 5-6 with permalloy indicates that this layer affected silicon nitride in the presence of Polyethylene glycolPEG.

• 트랜스-
• /
• 제6권
• /
• pp.43-78
• /
• 2019

무용은 '몸'을 표현의 도구로 사용하는 예술이다. 또한 한 번 행해지면 소멸되는 무형체성과 일회성을 특징으로 한다. 즉 무용은 살아있는 몸의 예술이기 때문에 문자로 기록하는 것은 난해하다. 오늘날 영상이라는 디지털매체의 발달은 기록을 용이하게 했지만 이 역시 여전히 무용작품의 시각적인 면만을 기록한다는 한계를 지닌다. 이러한 어려움에도 불구하고 춤의 기록과 보존이 중요한 것은 과거와 현재의 만남이자 현재적 시점에서 재현과 해석을 할 수 있는 근거가 되기 때문이다. 무용가의 기억을 통한 기록방법인 구술사는 이를 가능하게 열어준다. 무용가의 언어로 자신의 삶과 예술을 기억하며 채록하고 연구하는 구술사는 무용의 기록방법으로서 무용가를 주체적으로 드러낸다. 또한 이를 근거로 현재적 시각에서 무용사 뿐 만 아니라 무용이 사회와 맺게 되는 상호작용을 읽어냄으로써 역사를 보는 다양한 관점을 지니게 한다. 따라서 무용분야 구술사는 무용가의 구술을 채록하여 기록으로 남긴다는 의의와 함께 여기에 함께 기록되어진 '인간과 사회적 관계'들을 남기는 것이다. 이렇게 기록되어진 무용분야 구술사는 분석과 해석이 더 해져 무용사 읽기, 역사 읽기의 창이 된다.

• 한국레이저가공학회지
• /
• 제7권3호
• /
• pp.37-46
• /
• 2004

The shape and size variations of the nanopatterns produced on a polymer film using a near-field scanning optical microscope(NSOM) are investigated with respect to the process variables. A cantilever type nanoprobe having a 100nm aperture at the apex of the pyramidal tip is used with the NSOM and a He-Cd laser at a wavelength of 442nm as the illumination source. Patterning characteristics are examined for different laser beam power at the entrance side of the aperture($P_{in}$), scan speed of the piezo stage(V), repeated scanning over the same pattern, and operation modes of the NSOM(DC and AC modes). The pattern size remained almost the same for equal linear energy density. Pattern size decreased for lower laser beam power and greater scan speed, leading to a minimum pattern width of around 50nm at $P_{in}=1.2{\mu}W\;and\;V=12{\mu}m/s$. Direct writing of an arbitrary pattern with a line width of about 150nm was demonstrated to verify the feasibility of this technique for nanomask fabrication. Application on high-density data storage is discussed.

• 한국식생활문화학회지
• /
• 제23권4호
• /
• pp.455-461
• /
• 2008

The purpose of this study was to investigate the actual conditions, satisfaction towards, and effects of children's cooking activity programs held at children's cooking schools, which have recently been gaining interest as an effective integrated educational method. Also, based on the results, the study provides information on good teaching-learning methods, which can be applied to kindergarten and elementary schools. The results of the evaluation showed that 84.1% of the respondents were satisfied with the educational aspects of the programs. People were most satisfied with the teachers' "teaching ability", and were least satisfied with "the educational fees". The satisfaction scores for the children's cooking programs were higher when they were performed in a school class environment as compared to a cultural center environment, and children who had participated for more than 12 months were more satisfied than those who had only participated 1 to 3 months. Quantitatively, of the 24 measured evaluation categories grouped into 6 fields that measured the effects of participation in the cooking programs, the greatest effects were found on the children's self-confidence and sense of achievement in the social emotion field, and the lowest effect was found on their writing ability in the language field. In addition, scores were higher when the cooking activities were performed in a private cooking school environment as compared to a cultural center environment. Scores were also higher when the educational program lasted 7 to 9 months as compared to only 1 to 3 months.

• 대한공업교육학회지
• /
• 제31권2호
• /
• pp.128-154
• /
• 2006

지식기반사회에서 학교 교육의 질은 국가 발전의 핵심 요소이다. 교육의 질을 향상시키기 위해서는 무엇보다도 교육을 실제로 담당하고 있는 교사의 자질 향상이 중요하다. 그러므로 질 높은 교육 수준을 유지하기 위해서는 유능한 교원을 선발하고 임용하려는 노력이 필요하다. 이러한 시대 변화와 질 높은 교육수준을 유지하기 위해서 교사를 선발하는 임용고시의 중요성이 강조된다. 특히 공업계고등학교의 전기 전자 통신 과목의 임용시험은 기존의 세 분야 교과가 통합되면서 임용시험 문제 출제의 기준이 모호하여 전문교과 평가의 질적 저하가 우려된다. 이에 이 연구에서는 전기 전자 통신 과목의 교원 양성기관에 대한 교육과정과 제7차교육과정 및 기출문제를 분석하였다. 분석된 결과를 기초로 출제영역 비율 및 배점과 내용요소를 추출하였다. 추출된 내용은 전문가 협의회를 통해 검증한 후 다음과 같이 제시하였다. 첫째, 전기 전자 통신 과목의 임용시험은 교과교육학과 교과내용학 영역에서 출제되며 출제 비중은 교과교육학이 20%, 교과내용학이 80%로 한다. 둘째, 교과교육학의 하위영역은 '공업교육일반', '공업교육과정', '공업교수법', '실기지도법', '실습장조직관리', '공업교육평가', '산학협동교육', '직업 및 진로지도'로 구성한다. 셋째, 교과내용학은 공통전문, 기초전문, 응용전문으로 구성하고, 공통전문분야는 출제 비중이 7.4%, 기초전문분야는 20%, 응용전문 분야는 크게 전기분야, 전자분야와 통신분야로 나누며 각 영역의 출제 비중은 21.3%, 21.3%, 10%로 한다.