• Korean Journal of Metals and Materials
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• v.47 no.6
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• pp.363-371
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• 2009

The effect of lubrication on the evolution of strain states during shape rolling in AA5052 sheet was studied by the finite element method (FEM) simulation. The strain states calculated by FEM were verified by texture analysis. Shape rolling with and without lubrication produces shape-rolled samples in fairly similar outer shapes, since the distribution of normal strain components is nearly independent of the lubrication condition. In contrast, the distribution of shear strain components strongly depends on the lubrication condition. Shape rolling without lubrication gives rise to the development of strong shear strain gradients leading to the formation of highly inhomogenous textures and microstructures. The {011}//ND fiber develops during rolling with the operation of plane strain plus ${\dot{\varepsilon}}_{22}$.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.848-854
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• 2012

We have studied the oligomerization of a fibril-forming segment of ${\alpha}$-Synulcein using a replica exchange molecular dynamics (REMD) simulation. The simulation was performed with trimers and tetramers of a 12 amino acid residue stretch (residues 71-82) of ${\alpha}$-Synulcein. From extensive REMD simulations, we observed the spontaneous formation of both trimer and tetramer, demonstrating the self-aggregating and fibril-forming properties of the peptides. Secondary structure profile and clustering analysis illustrated that antiparallel ${\beta}$-sheet structures are major species corresponding to the global free energy minimum. As the size of the oligomer increases from a dimer to a tetramer, conformational stability is increased. We examined the evolution of simple order parameters and their free energy profiles to identify the process of aggregation. It was found that the degree of aggregation increased as time passed. Tetramer formation was slower than trimer formation and a transition in order parameters was observed, indicating the full development of tetramer conformation which is more stable than that of the trimer. The shape of free energy surface and change of order parameter distributions indicate that the oligomer formation follows a dock-and-lock process.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.126-131
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• 2003

The acceptance test of KTX has been performed in Korea. During the test, lateral vibration of carbody over the accepted value called sway was found. KTX has 20 car trainset formation whose trailer cars are linked by articulate bogies. So this study is performed to see the effects of long trainset formation on vehicle dynamics and the train stability by 20 car vehicle model. Firstly the reliable vehicle model which shows well the tendencies appeared in the tests on the high speed test line is required to find the cause of lateral vibration and the countermeasure. Vehicle model was made .for the. analysis with VAMPIRE. The analysis results show that secondary air spring lateral stiffness is the most significant parameter to cause carbody lateral vibration. Mode analysis results show that the least damped mode shape is similar to the vibration pattern shown in the tests that the amplitude of the motion increases along the train set and decreases in the tail part. For the case of short train formation with 7 or 10cars, sway does not happen. But in the case of longer train formation with 16 or 20 cars, sway was found.

• Journal of the Korean housing association
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• v.25 no.5
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• pp.83-91
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• 2014

The main purpose of this research is to understand how the problems, which existing letter-shape houses have, are solved in Unjoru which is one of the letter-shape houses. Furthermore, there is the secondary purpose which is to realize the architectural characteristics of Unjoru through the process from the composition of rooms and buildings to the method of structure and roof formation. This research was approached in terms of architectural design, and as the result, the problems of the existing letter-shape houses was resolved by literally converting the shape of outdoor space to 品-shape form. Moreover through the result, it was recognized that the 占-Shape plan was flexible in responding to the demand of the times, such as the order of precedency within men and women and each generation. In addition to the previous results, it was confirmed that the location of major rooms was also decided by considering the interrelationship with natural environment of surrounding area. Also, in the whole proportion of building's plan, each building, such as ㄷ-shape Anchae and big-sized and middle-sized Sarangchae having 丁-shape form, and major rooms in the each building have proportion system such as 1:1, 3:4, $1:\sqrt{2}$, and 3:5 as aesthetic numerical value. Finally, it was understood that the architectural intention had double-sided characters, one side was authority and dignity in the aspect of shape and another side was practicality in aspect of inner housing life.

• Journal of the Korea Fashion and Costume Design Association
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• v.15 no.2
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• pp.77-89
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• 2013

This study investigated the formation of silhouette and hemline shape of knit flare skirts according to the properties of knit material through virtual clothing with a 3D virtual clothing system called i-Designer of Technoa, thus building a database of the property data of knit material to reduce the number of sample making steps repeated and implemented several times in the process of clothes making. The results would help to estimate a silhouette in advance, offer assistance to the development of original knit wear, and explore ways to provide basic data for the development of the knit industry of the nation. The investigator made 12 kinds of experimental clothes to the angles(width of skirt: $90^{\circ}$ and $180^{\circ}$), gauge(7G, 12G, and 15G), and grain directions(wale and bias direction) of experimental clothes for virtual clothing. The dynamic characteristics of knit skirt samples according to each gauge were measured with the KES-FB system. Draper shapes were analyzed with the sectional shape data of hemline based on i-Designer. As for the measurements of the sectional shape of hemline and the formation of silhouette, the number of nodes, the average height of node mountains and valleys, and the hemline width right and left and before and after increased at the angle of $180^{\circ}$ than $90^{\circ}$. As gauges multiplied, the number of nodes, and silhouette angle dropping. When considering grain directions, the number of nodes and silhouette index increased in the wale direction at the angle of $90^{\circ}$ with the number of nodes and silhouette angle increasing in the wale direction at the angle of $180^{\circ}$.

• Korean Journal of Optics and Photonics
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• v.10 no.6
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• pp.518-523
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• 1999

In thi, study, we made experiments to fonn a mesa shape by meltback method with various concentration of solutions and found that unsaturated (20%) InGaAsP (1.55 !-tm) solution at a growth temperature was the most suitable for the formation of a mesa ,hape on the wafer which has an InGaAsP active layer and an InP cap layer on an n-InP substrate. It was difficult to form a proper mesa shape for the fabrication of PBH-LDs only by the meltback method; therefore, we fabricated PBH-LDs by forming the mesa shape with the meltback method after wet etching and by growing a current-blocking layer successively. As the electrical and optical charaleri,tiecs of MQW-PBH-LDs fabricated by above methods, when the cavity length was $300{\mu}m$, the threshold current was about 10 mA, internal quantum efficiency 82%, internal loss $9.2cm^{-1}$, and characteristic temperature was 65 K at $25~45^{\circ}C$ and 42 K at $45~65^{\circ}C$. /TEX>.

• Archives of Plastic Surgery
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• v.36 no.2
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• pp.242-246
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• 2009

Purpose: The majority of nasal bone fractures have been managed by routine procedure of closed reduction and intranasal packing. However, nasal packing can cause nasal injury, hypoxia and patient's discomfort. And, synechiae formation is a frequently occurred after the nasal surgery. Various methods are used to reduce the incidence of synechiae formation. The purpose of this study was to compare routine procedure and nasal packing with reverse "U" shaped silicone sheet with respect to postoperative nasal synechiae formation and final outcome. Methods: We analyzed the medical records of 100 patients with nasal bone fracture who were operated by closed reduction in the last one year. The silicone sheet was designed in reverse "U" fan - shape and inserted between the middle turbinate and the septal wall. Nasal packing was removed at two days after the operation, and silicone sheet was removed at 10 to 14 days. Results: Synechiae in the middle meatus developed in 2 of 75 patients. Although synechiae between the middle meatus and nasal septum occurred in patients, the patients did not complaint of any olfactory disturbance and nasal obstruction. Conclusion: The reverse "U" fan - shape silicone sheet caused less pain for patients and no significant differences in outcome were found. The results of this study suggest that insertion of silicone sheet between the middle meatus and septum can be a useful method in the prevention of intranasal synechiae formation. The reverse "U" silicone sheet is a good alternative for routine packing methods.

• Analytical Science and Technology
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• v.6 no.2
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• pp.149-156
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• 1993

The formation of the graphite spherulites has been studied experimentally in the Ni-C liquid under high pressure and temperature. In the diamond-stable region the graphite spherulites were formed and grew stably. They were not the polycrystalline particles but the single crystals of the fullerene-type, respectively, grown spirally with much imperfection. And they were proved to be in a mixture state of carbon atoms with $sp^2$- and $sp^3$-bonding by an Auger electron spectroscope and a high resolution transmission electron microscope. As the pressure decreased from the diamond-stable region to the graphite-stable region, the shape of the graphite particles changed gradually from the sphere to the flaky shape. The formation of the graphite spherulites was attributed to the stable existence of the carbon atoms with $sp^3$ bonding in the diamond-stable region. The formation of the large fullerene-type graphite spherulites with much imperfection is well agreed with Kroto's prediction for growth of the giant fullerene.

• Economic and Environmental Geology
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• v.29 no.5
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• pp.639-660
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• 1996

The lowest formation of the Cretaceous Gyeongsang Supergroup, the Nakdong Formation, unconformably overlies the gneiss complex basement in Hadong, Gyeongsangnam-do and Gwangyang, Chullanam-do. The Nakdong Formation of the study area is 500-600 m thick and occurs as a belt shape. Based upon lithology, sedimentary structure, and bedding geometry the formation consists of three conglomerate facies (Gd, Gn, Gic), five sandstone facies (Sh-n, Sh-i, Sp, Sr, Sm), and four mudstone facies (Mf, Mfn, Mc, Mv). Sandstone facies are the most prominent in the study area. The twelve facies can be grouped into five facies associations. The depositional settings are elucidated from analyses of 12 facies and five facies associations of the formation. The lower part of the Nakdong Formation was deposited in alluvial plain, and the middle and upper parts were in a riverine system. The lithologies of the Nakdong Formation of the Gyeongsang Basin have been considered to consist of generally conglomerates and pebbly sandstones that were accumulated in alluvial fans. But the common lithology of the study area is sandstone which was formed in lower part of alluvial fan or fluvial setting. It is supposed that the coarser sedimentary sequence distributed west to the study area should be eroded out after deposition and early uplift, and the finer sandstone sequence in the east remains behind. The mineral composition of sandstones and the clast composition of conglomerates indicate that the Nakdong Formation was derived mainly from the metamorphic source rocks. Some reworked intraclasts were also supplied from the intrabasinal sedimentary layers. Paleocurrent data collected from cross-beddings, ripple marks, asymmetric sand dune suggest that most sediments were transported from north to south during the Nakdong Formation time.

• Korean Journal of Metals and Materials
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• v.47 no.12
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• pp.881-886
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• 2009

Research into the replacement of injured systems and tissue in the human body is advancing rapidly. Recently, Ti-Ni shape memory alloys have shown excellent biofunctionality related to their shape memory effect and superelasticity. In this study, the effect of an acid or an alkali treatment on the bioactivity in 49Ti-Ni and 51.5Ti-48.5Ni alloys is investigated in an effort to utilize Ti-Ni alloy as a biomaterial. In addition, the biocompatibility in a SBF solution is assessed through in vitro testing. A porous surface was formed on the surface of both alloys after a chemical treatment. According to the in vitro test, apatite formed on the surfaces of both alloys. The forming rate of apatite in the Ti-rich alloy was faster that in the Ni-rich alloy. The formation of apatite provided proof of the bioactivity of the Ti-Ni alloy. A small quantity of Ni was eluted at the initial stage, whereas Ni was not found for 12 days in the Ti-rich alloy and for 8 days in the Ni-rich alloy. In the case of the treated 51.5Ti-Ni alloy, the shape memory property was worsened but the biocompatibility was improved.