The wheel is an active area of automobile component design and development. The wheel must be durable enough to tolerate significant loads and harsh environment. Temporary tire substituted for spare tire is made in a half band wheel size. Therefore this temporary tire is carried out lightweight and fuel saving of automobile. In this research, structural analysis and fatigue analysis of the temporary steel wheel are carried out using ANSYS 3D-modeling. The model is verified by the equivalent(von-Mises) stress analysis obtained from the ANSYS static structural analysis. Fatigue analysis is performed at the equivalent stress considering the automobile load and moment. Finally, this temporary wheel can be used temporary but not continuously.

This study presents a structural safety analysis method for a plant annunciator panel under the seismic effect. Seismic qualification analysis for the nuclear plant annunciator panel is carried out to confirm the structural integrity and the results are represented by required response spectra. For the numerical analysis, finite element method is adopted. Mode combinations are also used to obtain the reliability of the spectrum analysis. The analysis results shows that the nuclear plant annunciator panel is designed as a dynamically rigid assembly, without any resonance frequency blow 33Hz. The calculated stress of the nuclear plant annunciator panel is much less than yield stress of used steel.

The circular hollow section is usually used for member of main frame to carry the external load in single layer lattice dome. But, the H-shaped section may be used for member of main frame since it is convenient for attaching roof panels. Single layer lattice domes have various buckling characteristics, such as the overall buckling, the member buckling, and nodal buckling. The purpose of this study is to compare buckling characteristics of single-layer lattice domes in which the H-shaped steel section as the existing domestically-produced structural steel is used as main frames to those of domes in which a circular hollow section is used as main frames.

Accumulation of more than 20,000,000 vehicles since the establishment of the quality of life and economic development needs several parking lots and cause crack problem in Korea. Related structures in large cities due to the lack of parking garage attached to secure underground parking structures are actively being built, and the basement parking lot will continue to increase more stories and the trend is expected to be larger. But so far, construction of the underground parking structure is related to a number of problems, including cracks in the structure. Therefore, in this study, repair, reinforcement and a few non-economic losses in the current design criteria are presented. The review of the structure used to current design criteria is to minimize crack and maximize usability.

Recently, most of moving parts at automobile engine are required to be lighter and compacter and have high performances such as strength and endurance, etc. In particular, the crankshaft is subject to complex loadings such as shear, bending, and torsional loads as well as inertia and torsional vibration. To investigate critical area and optimize the shape of crankshaft at intial design stage, it is necessary to consider the dynamic effect of crankshaft. This paper carried out structural analysis of engine crankshaft by using multi-body dynamics and multi-axial fatigue analysis

In animals, structural coloration is the production of color by microscopically structured surfaces of many birds as well as many butterfly wings and beetles wing cases. This structural coloration is caused by interference effects rather than by pigments. It has been known that the colors are produced when a material is scored with fine parallel lines, formed of one or more parallel thin layers, or otherwise composed of microstructures on the scale of the colour’s wavelength. Current research is performed using light and scanning electron microscopes to examine the fine structural characteristics of scales in the three species of iridescent butterflies Papilio maackii, Charaxes tiridates and Anaea glaucone. It has been revealed that the structural coloration of these butterflies is responsible for the blues and greens of the scales of wings. In addition, the reflected color depends on the viewing angle, which in turn controls the apparent spacing of the structures responsible for specific color patterns of the wing scales.

Insects possess two distinct acetylcholinesterases (AChE1 vs. AChE2), which are encoded by two paralogous loci originated from duplication. Kinetic analyses of several insect AChEs revealed that both AChE1 and AChE2 retain common catalytic properties of AChE but subtle kinetic differences also exist between these two AChEs. To understand how selection pressure has shaped the protein structure of AChEs and affected their function during evolution, we measured and compared the nucleotide diversity (Pi) and amino acid site-specific selection pressure between AChE1 and AChE2 from various insects. Highly conserved were the majority of the amino acid residues involved in forming the essential domains, including peripheral anionic site (PAS), and little differences were revealed between AChE1 and AChE2, suggesting the presence of strong purifying selection pressure over these essential residues. Interestingly, the EF-hand like motif was mostly found in the AChE1 lineage but not in AChE2. In addition, a unique amino acid difference in the PAS (D72 vs. Y72) was highly conserved between AChE1 and AChE2. Three-dimensional modeling of insect AChEs by particularly focusing on the PAS revealed that a subtle but consistent structural alteration in the active site topology was caused by the PAS amino acid substitution. Taken together, despite the long evolutionary history and low overall sequence similarity, both insect AChE1 and AChE2 still share a extremely high degree of structural and functional conservation, indicative of a strong purifying selection pressure. Nevertheless, only a small change in the PAS, appears to be associated with a local but significant alteration of AChE2 structure, which in turn drives the functional differentiation of AChE.

Silk fibroin (SF) and silk sericin (SS) have been studied as a biomaterial due their useful properties including good blood compatibility and good cell activities. However, previous studies, silkworm variety has not been considered although it can affect structure and properties of silk fibroin and sericin. Therefore, in the present study, structure and properties of silk fibroins and sericins obtained from different silkworm variety were examined. Most of regenerated SF solutions from different silkworm varieties displayed Newtonian fluid behaviors and their viscosities were different depending on the silkworm variety. N74 showed the highest viscosity among the SF samples. Molecular weight (MW) distribution and mechanical properties of regenerated SF showed similar result to viscosity result. SS did not show significant difference in MW distribution and viscosity result depending on the silkworm variety.

In this study, silk sericin solutions and films were prepared with different solvents: formic acid and water. Also, silk sericin film from aqueous solution was prepared at different casting temperature. Regardless of solvent type, silk sericin solutions showed a shear thinning implying highly molecular entangled state of silk sericin. Silk sericin aqueous solution showed a higher turbidity than that of formic acid solution. Silk sericin aqueous solution showed shorter gelation time than formic acid. FTIR results showed β-sheet crystallization of silk sericin was affected by casting solvent and temperature. Silk sericin film from aqueous solution showed more β-sheet conformation as the casting temperature was decreased. Silk sericin film from formic acid showed higher crystallinity index than silk sericin films cast from aqueous solution. XRD diffraction measurement showed similar results to those of FTIR. In case of mechanical properties, tensile strength of sericin film from formic acid was higher than sericin films from aqueous solution.

This study aims to evaluate structural safety through FEM on the hollow shaft and the shaft filled with aluminum foam as the impact beam made of high tensile strength steel, Force reactions of impact beams are investigated when the forced displacement of 50mm is applied equally on two beams. When impact velocity of 80km/h is applied onto impact beams equally with the limit velocity of automobile on national road, how much impact energies can be absorbed by beams are also investigated. As study result, impact beams without aluminum foam and with aluminum foam show the maximum reaction forces of 15.53kN and 20.34kN respectively in case of the forced displacement of 50mm. As impact analysis result, impact beams without aluminum foam and with aluminum foam can absorb impact energies of 560J and 820J respectively. As impact beam with aluminum foam has reaction force and impact energy more than 23% and 30% than without aluminum foam, impact beam with aluminum foam has more safety than without aluminum foam.

We examined various ball-milling parameters which affect the structural and morphological modification of multi-wall carbon nanotubes. In particular, the effect of milling mode and the use of different milling agents were exam- ined. Friction milling mode induced more structural changes than impact milling mode except the use of dry ice as a milling agent. Wet milling was helpful for reducing more effectively the agglomeration of nanotubes than dry milling. The use of hard solid particles such as silica and alumina as milling agents resulted in an effective shortening of nan- otubes, but often susceptible to the amorphization and the destruction of crystallinity.

본 연구에서는 구조용강 내 크랙의 성장특성을 크랙의 길이와 각도에 따라 규명하였다. 구조용강으로 만들어진 시편 내의 크랙에 위에 언급한 두 가지의 조건들을 적용하여 실험을 수행하였으며, 이를 통해 Strain energy와 변형량에 대해 알 수 있었다. 그리고 이들 Strain energy와 변형량을 바탕으로 응력확 대계수를 구하였으며, 구해진 실험값들의 검증을 위하여 유한요소 해석 프로그램을 사용하여 시뮬레이션 해석을 수행하였다.

본 연구는 알루미늄 폼 복합재료로 접합된 TDCB 모델에 대해 구조적 시뮬레이션 해석을 하였다. 이 해석을 통하여 등가응력, 변형 에너지 및 접착부의 압력에 대한 자료를 얻었다. 또한 실험을 하여 해석 자료에 대한 검증을 하였다. 본 연구의 자료를 통해 알루미늄 폼 재질로 접합된 실제 복합재 구조물에 적용시켜 파괴거동을 분석하고 그 기계적인 특성을 파악할 수 있다.

As fires have frequently occurred with large scale at cultural assets and warehouses, the development of Korean type demolition fire apparatus for efficient fire fighting becomes important. In this study, structural stability is investigated for assembly model of boom and outrigger by using computational structural analysis. Analysis results of boom and outrigger unit are also compared with assembly model. As this study result, equivalent stress result of boom unit is about 6% higher than assembly model and equivalent stress result of outrigger unit is about 15% higher than assembly model.

회전하는 수조에서 나타나는 순압성 소용돌이의 패턴과 구조 회전에 대한 연구를 수행하였다. 소용돌이는 수면 위에 접촉된 원판을 수조에 대해 상대적으로 회전시키는 방법을 통해 만들어졌다. 회전원판의 크기, 회전방향, 회전속력에 따라 트라이폴라 소용돌이, 삼각형 소용돌이, 사각형 소용돌이, 커다란 원형 소용돌이가 안정하게 나타났고, 모양이 계속 변하는 불안정한 소용돌이도 나타났다. 회전원판과 수조 벽 사이의 간격이 안정한 소용돌이의 패턴에 큰 영향을 주었고 불안정한 소용돌이는 원판이 시계방향으로 빠르게 회전할 때 주로 나타났는데, 그 원인은 원심력적 불안정성이었다. 한편, 트라이폴라 소용돌이에서 나타난 전체 패턴의 구조적 회전 각속도는 원판 가장자리의 선속도에 비례하였고, 고기압성 트라이폴라 소용돌이가 저기압성 보다 더 큰 구조 회전 각속도를 가졌다. 로스비 수와 구조회전의 관점에서 볼 때, 해양에서 발견된 트라이폴라 소용돌이와 본 실험에서 나타난 트라이폴라 소용돌이는 유사하였다.

This project is mainly related to evaluation of total energy consumption of low energy house, the exterior envelope of which was wholly composed of structural insulated panels(SIP). The U-value of applied SIP was in the range of 0.189 to 0.269W/㎡․K and the U-value of pair glass from 0.78 to 1.298W/㎡․K was applied for window dependent to its function respectively. For comparison of total energy performance, the energy simulation for pilot house was performed to compare with the control house having insulation criteria of Korean building regulation in 2009. Based on simulation of dynamic energy performance, the pilot house saved 48.3% of annual energy consumption while the control house in 2009 consumed as 85.7GJ/y. In case of heating, the result showed that the energy saving ratio amounted to 76.7%. For CO₂ emission, the pilot house diminished approximately 35.4% from 6,208.4kgCO₂ to 4,009.2kgCO₂. In payback period to early investment, it was analyzed the pilot house took 7.8 years, when the low energy house built by other insulation method with same thermal perfusion took 11.5 years. From this result, it is considered that the SIP is more effective, economic to Green Home application.

The demand for the structural system of reduction in story height increases because buildings are getting higher. The existing method of construction is not efficiency. Thus, it is hard to reduce the story height and this method cannot secure economics as expected. This study aims at developing the partially concrete-filled new type composite beam, which can efficiently resist against the negative moment and positive moment, for the reduction of deflection. Through case studies on loading of concentrated load and uniformly distributed load to fixed beam, we could find the most efficient ratio of moment of inertia. Consequently the gap space between middle and end beam can be used as facilities installation, moreover the suggested Omega beam system is expected to get the effect of reduction in story height as well as reduction of quantity.