산화아연 막은 투명한 전도성 물질로써 다양한 분야의 광전자소자에 이용되고 있다. 그러므로 산화아연 막의 특성을 규명하는 것은 광전자소자의 성능을 높이는데 매우 중요한 역할을 할 것이다. 본 논 문에서는 이러한 산화아연 막을 용액공정 기반으로 제작하여 형태적, 구조적 특성을 평가하고자 한다. 구 체적으로는 졸-겔 방법을 반복적으로 시행하여, 시행 횟수에 따른 산화아연 막의 물성의 변화를 관찰할 것 이다. 일정한 용액 조건하에서, 5회의 반복적인 졸-겔 방법을 시행한 결과 결정화가 진행되는 것을 확인하 였다. 7회 이상에서는 원소 구성 및 결정화도가 특정 값에 수렴하는 경향을 보였다. 최종적인 산화아연 막 의 평균결정의 크기는 약 10.7 nm 정도로 계산되었다. 본 연구를 통해 최적의 결정화를 보이는 공정횟수 는 7회였다. 본 연구 결과 및 방법론은 다양한 용액공정 변수를 가변시키면서 적용할 수가 있고 최적의 공 정조건을 확립하는데 기여할 것으로 기대한다.

With the advancement of optical design and manufacturing technology, optical components have found diverse applications, spanning from semiconductors to the aerospace industry. A reflective mirror is a basic component in optics and plays a crucial role as the medium to reflect light. In this paper, a large mirror with a 700mm diameter was designed as a primary mirror using fused silica. The rear side of the mirror was subdivided into several equal angles, and neighboring vertices on the circumference were connected to establish a polygon. Accordingly, the geometric shapes of triangle, square, pentagon, and hexagon were formed. Furthermore, the mirror structure was strengthened by employing straight lines passing the vertices and the center of the circle. Based on the finite element analysis, deformations of the mirrors caused by the gravitational force were evaluated. Weight and deformation of the mirror structures were compared and analyzed to find a proper structure to reduce weight and deformation. This paper, therefore, presents a structural solution aimed at reducing the weight and deformation of a large aperture mirror induced by gravitational forces, thereby suggesting a geometric shape based structure to reduce surface deformation of a mirror.

In this study, In this study, structural analysis of a fuel tank for an SUV (sports utility vehicle) was performed for crack prevention design. Reservoir tank analysis was conducted for crack prevention design, and improvement measures for weak areas were discovered and reflected in the design. Pressure analysis was performed on the existing model to analyze weak areas. As a result of analysis through various design changes, it was found that the strength problem of the reservoir tank was due to the discontinuity of the rib inside the tank, and to improve this, it was necessary to minimize the discontinuity section.

This study examined the structural characteristics of the royal tomb equipped with only rail stones in the early Joseon Dynasty. Bongneung(封陵: the burial mound of royal tomb) equipped with only rail stones was constructed from 1468 to 1632. During this period, Hyeongung(玄宮: the underground chamber for the coffin of the king or queen) was constructed with lime. When the Hyeongung is completed, the soil is covered with a thickness of 1 foot parallel to the ground surface. On top of that, as the base of the Bongneung, the rail ground stone is constructed with a height of about 1.5 to 2 feet. The inside of the rail ground stone is also firmly filled with soil. On top of this, semicircular lime is installed with a convex center. Lastly the soil is divided and compacted several times to form a hill, and then covered with grass to complete the Bongneung. The notable feature is that between the Hyeongung made of lime and the Bongneung made of soil, the rail ground stone serves as a stylobate with the inside compacted by the soil.

Structural inversion refers to the reverse reactivation of extensional faults that influence basin shortening accommodated by contractional faults or folds. On the Korean peninsula, Miocene inversion structures have been found, but the Cretaceous rocks on Geoje Island may have undergone inversion as early as the Upper Cretaceous. To evaluate the structural inversion on Geoje Island, located on the eastern side of South Korea, and to determine the effects of preexisting weakness zones, field-based geometric and kinematic analyses of faults were performed. The lithology of Geoje Island is dominated by hornfelsified shale, siltstone, and sandstone in the Upper-Cretaceous Seongpori formation. NE and NW-oblique normal faults, conjugate strike-slip (NW-sinistral transpressional and E-W-dextral transtensional) faults, and NE-dextral transpressional faults are the most prominent structural features in Geoje Island. Structural inversion on Geoje Island was evidenced by the sinistral and dextral transpressional reactivation of the NW and NE-trending oblique normal faults respectively, under WNW-ESE/NW-SE compression, which was the orientation of the compressive stress during the Late Cretaceous to Early Cenozoic.

In a self-level riser, the piston rod generates hydraulic pressure while reciprocating along the pump rod, so components such as rods and valves require precise processing technology. Among them, the design of the pump rod was changed to a spiral groove method because there was a risk of poor operation during eccentricity. In this paper, the design and 3D modeling of the pump rod were conducted, and the structural stability of the core part according to the load change applied to the pump rod was confirmed.

Hexagonal bolt, nut, fittings, and high-pressure valves with special alloy play an important role in many industrial products, for instance, such as semiconductor facilities, hydrogen stations and fuel cell electric vehicles. The purpose of this study is to investigate the structural stability of turning wheel using the reaction force of roller in variable hexagonal rolling die. As the results, the bearing groove had the possibility of damage in turning wheel, especially, in case of Bottom condition. Furthermore, the turning wheel showed structural instability by using safety factor but structural stability using strength, respectively, as a safety criterion.

프리캐스트 코핑의 중공부 주철근 단절로 인한 단점을 보완하고, 거치대 삽입 없이 주철근을 거치대로 활용할 수 있 도록 철근-콘크리트 접촉부의 응력집중을 완화할 수 있는 하중분산세트의 성능을 검토하였다. 유한요소해석 및 축소모형실험을 통해 검토한 결과 하중분산세트는 철근-콘크리트 접촉부의 응력집중을 효과적으로 완화시켜 거치 시 콘크리트 파손을 방지할 수 있을 것으로 판단된다.

In this experimental work, a p-type c-Si (100) substrate with 8 × 8 × 2 mm dimension was taken for TiCN thin-film coating deposition. The whole deposition process was carried out by chemical vapor deposition (CVD) process. The Si substrate was placed within the CVD chamber at base pressure and process pressure of 0.75 and 500 mTorr, respectively, in the presence of TiO2 (99.99% pure) and C (99.99% pure) powder mixture. Later on, quantity of C powder was varied for different set experiments. The deposition of TiCN coating was carried out in the presence of N2– H2–TiCl4–CH3CN gas mixture and 600 ℃ of fixed temperature. The time for deposition was fixed for 90 min with 10 and 5 ℃ min− 1 heating and cooling rate, respectively. Later on, heat treatment process was carried out over these deposited TiCN samples to investigate the changing characteristics. The heat treatment was carried out at 800 ℃ within the CVD chamber in the absence of any gas flow rate. The morphological properties of heat-treated samples have been improved significantly, evidence is observed from SEM and AFM analyses. The structural analysis by XRD has been suggested, upgradation in crystallinity of the heat-treated film as it possessed with sharp and higher intensity peaks. Evidence has been found that the electrochemical properties are enhanced for heat-treated sample. Raman spectroscopy shows that the intensity of acoustic phonon modes predominates the optic phonon modes for untreated samples, whereas for heat-treated samples, opposite trends have been observed. However, significant degradation in mechanical properties for heat-treated sample has been observed compared to untreated sample.

국제유가가 배럴당 85달러에서 하반기에는 최대 100달러까지 오를 것으로 예상하여 세계 시장에서 해양플랜트 발주가 늘어 날 가능성이 크다. 해양플랜트의 주요 특징 중 한 가지는 탑사이드에 대형 헬리데크가 위치하며 경량화 및 내부식성을 위하여 알루미 늄 합금을 구조의 기본 재료로 사용하고 있다. 선주사는 긴급 상황 발생 시 신속한 인명 대피를 위하여 헬리콥터 크기를 대형화하는 추세이고, 헬리콥터를 데크에 안정적으로 고박할 수 있는 장치의 안전사용하중도 증가가 필요하다. 알루미늄 재질의 특성상 용접에 의 한 구조 강도 저하가 크기 때문에, 고정 장치는 데크에 매립하여 볼트로 고정하는 방식으로 설계가 필요하다. 본 연구에서는 대형 헬 리데크(직경=28m)에 사용이 가능한 헬리콥터 고정 장치를 개발하기 위하여 알루미늄 합금 6082-T6를 적용한 모델을 개발하였다. 개발 된 고정 장치는 실제 고박에 사용하는 하중 조건을 만족하도록 비선형구조 강도 계산을 통하여 검증하였다. 45도 경사각을 갖는 하중 조건은 국부적인 소성 붕괴로 인하여 90도 조건에 비해 낮은 최종강도를 나타냈다. 최종 모델에 대한 비선형 구조 붕괴 거동은 강도 실험과 경향이 유사하게 나타났다. 본 연구에서 도출한 주요 내용은 유사 알루미늄 기자재의 구조 강도 검토 시 참고 문헌이 될 것으 로 판단된다.