• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 춘계학술발표대회 논문집
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• pp.69-72
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• 2002

The high temperature deformation behavior of SiCp/2124Al composite and 2124Al alloy was investigated by hot compression test in a temperature ranged $400~475^{\circ}C$ over a strain rate ranged $10^{-3}~1s^{-1}$. The billets of 2124Al alloy and SiCp/2124Al composite were fabricated by vacuum hot pressing process. The stress-strain curve during high temperature deformation exhibited a peak stress, and then the flow stress decreased gradually into a steady state stress with increasing the strain. It was found that the flow-softening behavior was attributed to the dynamic recovery, local dynamic recrystallization and dynamic precipitation during the deformation. The precipitation phases were identified as S' and S by TEM diffraction pattern. Base on the TEM inspection, the relationship between the Z-H parameter and subgrain size was found based on the experiment data. The dependence of flow stress on temperature and strain rate could be formulated well by a hyperbolic-sinusoidal relationship using the Zener-Hollomon parameter.

• 대한가정학회지
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• 제47권3호
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• pp.1-9
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• 2009

This study was conducted to examine how patchwork was expressed in fashion based on theoretical background on its brief history and expression styles and to show its possibility of creating ways for new expression in modern fashion. This study reviewed literatures on definition, history and styles of patchwork and investigated mainly works, which had been presented in collections home and abroad since 2000, to analyze its expressive characteristics shown in modern fashion. According to analysis on the expression of patchwork, it used various painting techniques such as patterns, colors and surface effect. It included patchwork having patterns provoking elusion of fairy tails; containing painting expression of reproducing works of artists; using colors boldly and contrasting strong primary colors directly to establish purity of painting and to pursuit characteristic expression; and using expression techniques of pure art such as gradation and cutting. Second, it used a compromise expression in materials, methods and substances. Patchwork which had used cloth without a pattern or printed fabric, utilized various materials like vinyl, paper, leather, metal and plastic and had a figurative value showing a solid expression as an objet itself with new techniques and changes of connecting methods. Thirdly, it used tradition patchwork techniques. Pieced patchwork, crazy patchwork and images of traditional odd ends of cloth covering a meal were applied to a whole area or a part of cloth to avoid monotony of design and to use it as a decoration.

• 한국생산제조학회지
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• 제21권4호
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• pp.658-665
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• 2012

Micro-EDM is widely used in metallic pattern, electronics, nuclear power and industry in the form of precision process. The improvement of Electro Discharge Machining has been on a steady progress since $19^{th}$ century. The technology has overcome the limits of the traditional precision process, enabling micro-EDM, micro electrolytic machining, micro drilling, micro punching and laser beam machining, which create versatile products with smaller sizes. What have been known about the major feature of Micro-EDM is high thermal energy so that their products are free from the hardness of their products as long as they are electrical conductor. However, each metal is suspected to have different features and natures even if they are created through the same procedure. In this thesis, the methodology of Micro-EDM and how to categorize them are explained. Also, the nature of the examined materials with surface shape and surface roughnes are analyzed. The results of the experiments are expected to understand surface roughness and workability of other materials for Micro-EDM.

• 한국레이저가공학회지
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• 제12권3호
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• pp.1-6
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• 2009

This paper describes the method for the fabrication of micro dot array on a plastic mold steel using DPSS (diode pumped solid-states) UV laser and wet etching process. We suggest the process of the ablation of a photoresist (PR) coated on plastic mold steel and wet etching process using solutions of various concentrations of $FeCl_3$, $HNO_3$ in water as etchant. This method makes it possible to fabricate metallic roller mold because the microstructures are directly fabricated on the metal surface. In the range of operating conditions studied, $17\;{\mu}J$ laser pulse energy and 50 ms laser exposure time, an etchant containing 40wt% $FeCl_3$, 5wt% $HNO_3$ and etch time for 45 s gave the $10\;{\mu}m$ of micro dot pattern on plastic mold steel.

• 패션비즈니스
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• 제14권3호
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• pp.1-19
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• 2010

The Assyrians usually wore two types - the tunic and the shawl. These two types were worn alone, or in combination and changes were introduced by varying the proportions of the tunic or shawl. The tunic appeared to be of the sleeves are short and reaching to the ankles or shortened to knee length according to the rank. Assyrian shawl pattern can be divided into five distinct styless. Many of the styles were suitable for costumes to wear in religious plays and pageants. Fringed shawls were the trademark of forma1 Assyrian costume. The usual badge of rank was a long fringed shawl. Intermediate rank wore shawl with short fringes and lower grade wore no shawl at all. The military costume was comparative uniformity : conical helmets was regarded as Scythic in character, short, fringed tunics, wide belts or helmet, round caps and long tunics covered in metal scales, belted at the waist. Assyrian woman costume was the long tunic with fringed hem and a long fringed shawl or was a plaid tunic and wide belt over it. They wore gold crown and horned Cap and tiara, ugal (head-dress) and the most ordinary earrings were the drop and the cross shape and necklace was made of the coloured stones and bracelets ended with heads of animal was regarded as Scythy style or adorned with a rosette at the centre.

• 한국식품조리과학회지
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• 제18권4호
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• pp.448-454
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• 2002

This study was performed to develop Cnidium officinale-flavored oils. Cnidium officinale is one of the Korean aromatic medicinal plants. The flavor patterns of Cnidium officinale-flavored oils during storage were detected by using an electronic nose with 6 metal oxide sensors, and a principal component analysis (PCA) was carried out. The overall acceptability of flavor and the masking effects on fetid smell of beef of Cnidium officinale-flavored oils were investigated by sensory evaluation. In COI-flavored oil, flavor patterns between the storage samples for 1 week and 16 weeks could be distinguished. And in CO II-flavored oil, flavor patterns between the samples stored for 1 week and 8 weeks and the flavor patterns between the samples stored for 1 week and 16 weeks in CS I-flavored oil could be distinguished. In CS II-flavored oil, flavor patterns of the samples stored for 1, 4, and 8 weeks also could be distinguished. Fetid smell in beef was significantly reduced by the addition of COI- and CS II-flavored oils. As the storage time increased, overall acceptability of Cnidium officinale-flavored oil decreased, indicating that Cnidium officinale-flavored oils were most preferred at 8 weeks of storage.

• 한국식품조리과학회지
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• 제18권4호
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• pp.455-460
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• 2002

This experiment was conducted to obtain basic information on the natural spice of Elsholtzia splendens, which is one of the native Korean aromatic plants for aromatic, medicinal and ornamental uses. The overall acceptability and the masking effects on the fetid smell of beef were investigated with Elsholtzia splendens-flavored oils by sensory evaluation. The ability of an electronic nose with six metal oxide sensors to classify Elsholtzia splendens flavored oils based on their odors was studied. The response by electronic nose was analyzed by principal component analysis (PCA). In EOI, EOII, and ESI, (이것들이 무엇을 의미하는지 기술할 필요가 있음). overall acceptability of French dressing showed a same level of preference during storage. Fetid smell of beef was not changed by the addition of 4 types of Elsholtzia splendens-flavored oil during storage. In EO I -flavored oil, the proportion of 1st principal component was 0.829, and the proportion of 1st principal component was 0.818 in ESI-flavored oil. The PCA plot was used to detect stored Elsholtzia splendens flavored oils.(앞 뒤 문맥이 안맞음. 뒤에 이어지는 글이 있는지\ulcorner).

• 한국정밀공학회지
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• 제2권2호
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• pp.31-42
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• 1985

The metal flow and the strain distribution is investigated for the steady state and non-steady state bulk deformation processes by using an improved visioplasticity method which includes the effective smoothing scheme. The comparison of various smoothing schemes leads to the selection of the five- point least square smoothing method which is employed to reduce the measurement errors. As a steady state forming process experiments are carried out for axisy- mmetric forward extrusion through conical and curved dies of various area reduc- tions using Aluminum and steel billets. Axisymmetric backward extrusion is chosen for a nonsteady state forming process. In axisymmetric forward extrusion the results from visioplasticity show that the curved die of a fourth-order polynomial renders more uniform distribution of strain rates and strains. Higher reduction leads to greater strain rates at the outer side of the billet. The visioplastic observation for axisymmetric backward extrusion as a non-steady state deformation process shows the concentration of higher strain at the inner wall of the extruded product. The visioplastic results in forward extrusion are in agreement with the computed results by the finite element method. It is thus shown that the visio- plasticity combined with a smoothing technique is an effective method to determine the pattern and the distribution of strain rates and strains.

• Journal of Welding and Joining
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• 제21권1호
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• pp.48-53
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• 2003

The object of this study is to examine the effect of short circuit time ratio (SCTR) and current rise delay time (Td) on the spatter generation at low and medium current range in $CO_2$ welding. The spatter was evaluated by the weight generated in the welding of bead-on-plate for 30 seconds (3 times). Td was varied by order of 0, 0.4, 0.8 and 1.2 msec. At each Td, the short circuit time ratio was varied by the output voltage of the welding power source. In the low current range, it was found that the optimum SCTR was 20~25%, and the minimum spatter generation weight was obtained in the case of Td=0.4msec and SCTR=22% even though the remarkable difference was not showed by the application of Td. In the medium current range, it was confirmed that the arc was stable though the SCTR was increased from 20% to 40% by the control of current wave. Spatter generation weight depended on the variation of Td, and the lowest value of spatter generation weight occurred at Td=0.8~1.2msec.

• BMB Reports
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• 제28권2호
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• pp.170-176
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• 1995

Rhodanese from mouse liver was purified to near homogeneity by ammonium sulfate precipitation, CM-Sephadex ion exchange, hydroxyapatite and Sephacryl S-200-HR gel filtration chromatographies with a purification of 776 folds. The molecular weight was determined by Sephadex G-150 gel filtration and found to be 34.8 KDa. SOS-PAGE showed molecular weight 34 KDa and two identical subunits splitting by aging for 3 weeks at $-70^{\circ}C$ the molecular weight of which was 17 KDa. The optimal pH of enzyme activity was 9.4 and the pI value of the enzyme was 6.6. Rhodanese showed the optimal reaction temperature of $25^{\circ}C$ and near linear increasing pattern until 10 min. incubation. $K_m$ values of rhodanese for KCN and $Na_{2}S_{2}O_{3}$ as substrates were 12.5 mM and 8.3 mM, respectively. Rhodanese activity was inhibited by more than 70% at a concentration of 100 ${\mu}M$ of $Ni^{2+}$, $Zn^{2+}$, $Cd^{2+}$, $Hg^{2+}$ and $Cu^{2+}$. Other metal ions, such as $Mn^{2+}$, $Mg^{2-}$, $Ca^{2+}$, and $Fe^{2+}$ showed no effect on rhodanese activity.