• Journal of Powder Materials
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• v.17 no.4
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• pp.312-318
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• 2010

High speed steels (HSS) were used as cutting tools and wear parts, because of high strength, wear resistance, and hardness together with an appreciable toughness and fatigue resistance. Conventional manufacturing process for production of components with HSS was used by casting. The powder metallurgy techniques were currently developed due to second phase segregation of conventional process. The powder injection molding method (PIM) was received attention owing to shape without additional processes. The experimental specimens were manufactured with T42 HSS powders (59 vol%) and polymer (41 vol%). The metal powders were prealloyed water-atomised T42 HSS. The green parts were solvent debinded in normal n-Hexane at $60^{\circ}C$ for 24 hours and thermal debinded at $N_2-H_2$ mixed gas atmosphere for 14 hours. Specimens were sintered in $N_2$, $H_2$ gas atmosphere and vacuum condition between 1200 and $1320^{\circ}C$. In result, polymer degradation temperatures about optimum conditions were found at $250^{\circ}C$ and $480^{\circ}C$. After sintering at $N_2$ gas atmosphere, maximum hardness of 310Hv was observed at $1280^{\circ}C$. Fine and well dispersed carbide were observed at this condition. But relative density was under 90%. When sintering at $H_2$ gas atmosphere, relative density was observed to 94.5% at $1200^{\circ}C$. However, the low hardness was obtained due to decarbonization by hydrogen. In case of sintering at the vacuum of $10^{-5}$ torr at temperature of $1240^{\circ}C$, full density and 550Hv hardness were obtained without precipitation of MC and $M_6C$ in grain boundary.

• Journal of Conservation Science
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• v.33 no.3
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• pp.155-165
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• 2017

As interest in the public display of art and outdoor sculptures is increasing, the conservation and treatment of these sculptures is becoming increasingly crucial. Long-term exposure to the natural elements and atmospheric pollution can cause corrosion and deterioration in outdoor sculptures. In the case of Kim Chan Shik's "Feeling", which was exhibited in the outdoor sculpture park at the National Museum of Modern and Contemporary Art (MMCA), the patina of the sculpture was damaged during a long outdoor exhibition. Therefore, the treatment process was as follows: recording of condition, sanding, repatination, and wax coating. Consequently, the sculpture was restored similar to the original. Chemical analysis revealed that the sculpture was crafted from bronze and was cast from a quaternary alloy of Cu-Pb-Sn-Zn. The welding is lower in Zn, Sn, and Pb content than the metal used in the sculpture itself. Bright strains contain about 13.0 wt% Sn and 10.5 wt% Pb. The strains are higher in Sn and Pb content than the rest of the metal in the sculpture (7.0 wt% Sn and 4.4 wt% Pb). As a result of component analysis and microstructure observation, the material is estimated to have been made by casting without artificial treatment.

• The Korean Journal of Community Living Science
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• v.17 no.1
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• pp.11-21
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• 2006

This research is focused on not only cultivated land as an important factor which represented the agricultural district, but also details of the research in the landscape of cultivated land. Moreover, we also focused on the cultivated land operating environmental friendly agriculture which took a lot of interest among the landscape of the cultivated land. The reason is, we judged environmental friendly agriculture is not only the simple purpose only for manufacturing food but also the key role for preserving their environment and landscape, and making sustainable agriculture. For this reason, our research treats the analysis that operating environmental friendly landscape has what kinds of different factors in landscape characteristic compare with other general agricultural methods. Plus we selected evaluating both the degree of citizen's presence and the degree of rural residents's importance in those factors as a mainly research matter. We drew out the landscape of cultivated land and concerning factors by analyzing policies(ESA, CSS, CTE, MFSP, ACL, etc) concerned with overseas agricultural landscape to deduct landscape Character factors in internal cultivated land. Based on eleven items of landscape factors in cultivated land deducted by documents research, we started to conduct field studies during MAY. 7th. 2004 $\sim$ JUL. 8th, DEC. 1th $\sim$ 3th reaching 32 villages and concerned institutes to deduct the factors in landscape characteristic in agricultural cultivated land in detail. We analyzed degrees of importance and preference in citizen and rural residents classified by 5 province of the whole country to evaluate the landscape Character factors in environmental friendly agriculture deducted by field research and 21 documents including extra items such as a scene of duck grazing by the duck techniques which is very popular way among internal environmental friendly agriculture, gardening space composed around farm and furrow on slope ground formed by unique topology in hilly country. The research period was progressed for 20 days from MAY. 28th. 2005 $\sim$ JUN. 17th. This research is the result that cultivated land landscape as a detail item holding agricultural environment especially, it is also meaningful result in environmental friendly agriculture as a basic research, because it is not only a value of simple food producing but also very effective role in both landscape and environmental parts.

• Journal of the Korean Magnetics Society
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• v.5 no.3
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• pp.216-221
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• 1995

Both manufacturing parameters and particles' chemical composition controll coercivity and its distribution of magnetic particles. The coercivity and its distribution are important properties for high density magnetic recording, so these are used as tool for evaluation of reproducibility of magnetic particles. We report in this paper the applications of dM/dH versus H curve, which is derived from magnetic hysteresis loop, to the evaluation of coercivity distribution of magnetic particles and oxidation studies of recording metal particles. The coercivity distri-bution can be estimated from the full width half rnaximun (FWHM) and the peak shape of the dM/dH versus H curve. The peak shape of the curve depends upon distribution of particles' coercivity. The peak of dM/dH versus H curve becomes broad and lor is splitted into two or rmre peaks. It depends on uniformity of particles' coercivity. When the coercivity difference between Ba-Ferrite and ${\gamma}-Fe_{2}O_{3}$ is larger than 600 Oe, the peak becomes broad and is consequently splitted into two peaks. Ununiformly substituted Ba-Ferrite particles show broad peak. It is apparent that the analysis of the curve is one of sensitive measuring techniques for determination of coercivity distri-bution and studies on magnetic properties of substituted Ba-Ferrite and oxidation of magnetic recording metal particles.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.513-526
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• 2020

The existing preservation methods are difficult to be applied to a large dimension log which is needed for making traditional wooden ship 'Jalur' in Riau Province. Novel techniques to provide the use of readily available species to replace traditional species alternative were investigated. These included infusion and a combination of injection and bandage-wrapping methods for preserving living trees of Balam (Macaranga conifera (Rchb.f. & Zoll.) Müll.Arg.) and Bintangor (Calophyllum soulattri Burm.f.). Water-based boron compounds were applied as wood preservatives. In total, 18 discs from the bottom, middle, and top of four trees and two controls were used. Trees undergoing treatment were also used to see how wood anatomical structure might affect the boron penetration. The overall aim was to identify the best method for use in Jalur manufacturing. The results showed that in infused Balam tree where the hose position for the preservative intake was deep (10-15 cm from the bark), no boron compound was observed in the outer sapwood. Combination of injection and bandage-wrapping method gave higher percentage of boron penetration at bottom and middle of Balam tree. However, infused Bintangor showed 100% boron penetration. The larger vessel diameter, the absence of tyloses, and the simple perforation plates in Bintangor wood were likely to have contributed to the higher penetration of boron. The combination of bandage-wrapping and infusion, or alternatively by infusing the living trees close to the bark, and at as low as position in the stem gives better protection when treatments are applied to living trees.

• Journal of Conservation Science
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• v.29 no.1
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• pp.69-79
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• 2013

This study aims at identifying the variation of physicochemical properties for galena ore in order to use it in understanding of manufacturing techniques in terms of metallurgical method and smelting or refining process for obtaining lead. The ores in the study obtained from the operating mine have been washed and pre-treated for a test. Metallic lead has been extracted by roasting process. The result displays that galena is still in present in the matt despite of exposure to high temperature, over $1000^{\circ}C$. Nearly $11.1g/cm^3$ specific gravity metallic lead has been collected from the refining test of which aim was to remove the remnant galena and a trace of concentrated silver has been identified at the grain boundary. The result suggests that at least one refining process was essential to acquire high purity metallic lead and cupellation had been executed to remove remnant silver.

• Journal of Conservation Science
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• v.36 no.5
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• pp.405-420
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• 2020

A convergence research was conducted on glass beads excavated at the ruins of Hapgang-ri, Sejong, using the archeology and conservation approach. The period of appearance of Jugu Towangmyo in the ruins of Hapgang-ri can be estimated to begin in the late 2^nd century; for Jugu Towangmyo No. 15, the period spans from the late 2^nd to early 3^rd century. Form, color, and manufacturing techniques of complete glass beads were examined, and the cross-sections and chemical composition of 16 samples were observed. Based on these analyses, the glass beads were divided into blue, purple, and red colors. The blue-colored beads could be further sub-divided based on their gloss and brightness; in contrast, the red-colored beads were highly uniform with regard to these parameters. Based on the stripe and bubble arrangement on the surface of the glass beads, their drawing technique was identified. Traces of heat treatment or polishing were observed at the ends of the beads. According to their chemical composition, the 16 samples were classified into 3 potash glass and 13 soda glass groups; in the latter, the properties of the stabilizers were divided according to the blue and red bead colors. The stabilizers of the red beads are unique in that they allow the distinction among beads excavated in other areas in South Korea owing to their compositional differences. Colorants in blue- and red-colored beads are cobalt (containing MnO), and copper and iron, respectively.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.414-420
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• 2014

This study was performed to increase the yield and to reduce the processing times for the preparation to improve the productivity and quality of rice jochung, a traditional food in Korea. In order to evaluate the quality characteristics and yield of jochung, the viscosity, color value, mineral contents and the sensory evaluation were measured. Jochung is prepared from steamed rice (STR), wet-milled rice flour (WRF) and dry-milled rice flour (DRF) by processing methods of rice and reacting times (6 hours or 13 hours) of liquefaction and saccharification. There is commonly added liquefying enzyme for rice liquefaction (0.4%/10 kg rice, at $85{\sim}90^{\circ}C$ for 1 hour or 4 hours) and saccharogenic enzyme with malt (2.5% or 4.5%/10 kg rice, at $56{\sim}60^{\circ}C$ for 5 hours or 9 hours). The inner structural properties of WRF showed the more distinct shape regular structure of uncombined starch particles but the DRF closely maintained particles of rice flour observed by SEM. If processing times for liquefation and saccharification were reduced from 13 hours to 6 hours, the yield of jochungs prepared with WRF increased 8%, the DRF 7%, and the STR 3% respectively and the sensory evaluation as well as color values and overall desirability received high scores. The viscosity, color a and b values of jochung processed with WRF for 6 hours were lower than that processed for 13 hours. The viscosity and color a, b value and Ca content were decreased in the jochung processed with WRF or DRF for 6 hours, but Mg, P and K were increased than that of STR. Jochung processed by 0.4% liquefying enzyme and 2.5% malt with WRF for 6 hours will increase the yield, save manufacturing times and costs and will thereby enable cost-effective techniques.

• Archives of design research
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• v.11 no.1
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• pp.131-142
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• 1998

Gustav KJimt (l862-1916)was a pioneer in the field of painting and decorative art. He was severly critized by the art critics of the time because of his rebellous art style. He firmly believed that there should exist a new kind of art that should portray the essence of the new liberalized era and that shoud reveal the idea of an artist in his work. Klimt was an aesthetic who sought beauty in life. He represented man as a micro universe within the macro universe. In order to portray man's inner being and to depict the process of life and death in nature, he symbolically employed female entity as a medium. Through uses of the circles, triangles, rectangles, and the spiral forms in his paintings, Klimt symbolized the meanings of man and nature. The circle symbolizes the universe and female entity; the triangle, human being; the rectangle, the earth and male entity; and the spiral, a universal force that attracts the opposite poles. The highly decorative characteristic nature of Klint's paintings and murals has often been modified in the pattern design field. It has been applied to home-furnishings and apparel textile designs, stained glasses, tiles, and posters. The techniques and layouts of these designs have been modified so that they may suit their manufacturing processes. In general, these pattern designs have two spectrums. One is the kind of design that has faithfully carried out Klimt' s original painting style. The other is the kind that has extracted the essence from the Klimt' s original art work.

• Food Science and Preservation
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• v.24 no.5
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• pp.593-599
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• 2017

The objective of this study was to investigate the effect of superheated steam (SHS) and high hydrostatic pressure (HHP) techniques on the improvement of the quality of Bulgogi product during manufacturing process. Bulgogi product was treated with four different cooking/treatment process: conventional cooking (CC), SHS cooking (SHS), CC and then HHP cooking (CC-HHP), and SHS and HHP cooking (SHS-HHP) samples. SHS treated product increased moisture content, and decreased crude protein. Additionally, hardness, gumminess and shear force values were significantly different among the samples (p<0.05). In safety experiment after 14 days of storage at refrigeration temperature indicated that the bacterial population was lower in the case of SHS-HHP as compared to CC-HHP. Changes in texture during the storage periods at $10^{\circ}C$ for SHS-HHP was lowest values with compared to the initial, while shear force values for both tended to decrease with increasing storage period. The TBA and VBN values for SHS-HHP increased to 0.48 ($5^{\circ}C$)-1.68 ($10^{\circ}C$) mg MD/kg and 25.14 ($5^{\circ}C$)-45.14 ($10^{\circ}C$) mg%, respectively after 15 days of storage. Overall, it was found that the combination of SHS and HHP reduced microbial growth, thus leading to improved product quality and sanitation.