• Title/Summary/Keyword: Gold section

Search Result 55, Processing Time 0.023 seconds

Operating Properties for a Resistive SFCL of YBCO Thin Films (YBCO 박막의 저항형 초전도 한류기에 대한 동작 특성)

  • Choe, Hyo-Sang;Hyeon, Ok-Bae;Kim, Hye-Rim;Hwang, Si-Dol;Kim, Sang-Jun;Mun, Seung-Hyeon;Han, Byeong-Seong
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.48 no.10
    • /
    • pp.537-543
    • /
    • 1999
  • We fabricated a resistive superconducting fault current limiter (SFCL) of a meander type based on a YBCO film with the meander cross section of 5 $\times$ $10^{-6}$$cm^2$, and performed current limitation experiments. The film was coated quench current was 9.6 Apeak at 60 Hz, and the fast quench time was 0.63 msec. The resistance of the limiter continuously increased for three cycles dut to the temperature rise in the gold layer. The temperature of the current limiting element reached the room temperature in 11 msec, $150^{\circ}C$ in 54 msec after quench, and was saturated afterwards. For $45^{\circ}$and $90^{\circ}$faults the fast quench times were 0.56 msec and 0.26 msec, respectively. The quench time is believed to be reduced because the fault occurred when the current was either increasing or at the peak value. This limiter effectively limited the fault current to about 1/5 of the potential current with no SFCL right after the fault and to about 1/8.5 in three cycles. We confirmed that the gold layer effectively carried out the role of heat dissipation as the SFCL was quenched.

  • PDF

Fabrication of Combined Probes for Interstitial hyperthermia and Brachyradiotherapy (고 선량율 근접 및 온열치료 병용 삽입관의 제작과 특성)

  • Chu, Sung-Sil;Kim, Sung-Kyu
    • Proceedings of the Korean Society of Medical Physics Conference
    • /
    • 2004.11a
    • /
    • pp.85-87
    • /
    • 2004
  • We fabricated flexible thermoradiotherapy probes to alternated combination with Interstitial hyperthermia and Brachyradiotherapy thermoradiotherapy probe was coated by gold plate on polyethylene brachytherapy probe. When Agar phantom was heated 15 minute with 30 W radiofrequency power, temperature increased as 5oC for polyethylene probe and 20oC for gold coated polyethylene probe. We observed that the 1 cm square array would heat a volume with a 1.25 cm radius circular field cross section to therapeutic temperatures (90% relative SAR using Tm) and the 2 cm square array with a 1.75 cm radius rectangular field with central inhomogeneity. With 2 cm long electrode implants, we observed that the 1 cm square array would heat a 3 cm long sagittal section to therapeutic temperature (90% relative SAR using Tm). The histopathological changes associated with RF heating of normal canine brains have been correlated with thermal distributions. RF needle electrode heating was applied for 50 min to generate tissue temperatures of 43${\circ}$C. We obtained a quarter of the heated tissue material immediately after heating and sacrificed at intervals from 7${\sim}$30 days. The acute stage was demonstrated by liquefactive necrosis, pyknosis of neuronal element in the gray matter. Mild gliosis occurring around the necrosis was demonstrated in the last sacrificed (days30)canine brain.

  • PDF

Form and Material Analysis of Yuso Used in Joseon Period Scroll Paintings (조선시대 족자 장황에 사용된 유소 형태 및 재질분석)

  • Jang, Yeonhee;Yun, Eunyoung;Kim, Yein;Park, Jinyoung
    • Conservation Science in Museum
    • /
    • v.17
    • /
    • pp.69-84
    • /
    • 2016
  • Yuso is the term for decorative tassels of a braided string which hangs a scroll painting. This study, drawing on extant research concerning the yuso made for Joseon period portrait scrolls of kings and meritorious retainers, focuses on the yuso created to hang literati portraits. Concretely, It examines yuso of seven portraits in the collection of the National Museum of Korea in order to characterize their appearance and determine their material composition. The study found that most of the yuso are sixteen-strand strings braided into a rounded cross-section(dongdahoe). The seven yuso, of which six are red and one indigo-blue, reflect the popular style associated with Joseon period literati portraits. The yuso for the portrait of Yun Geup(duksu 3503) is made from gilded paper. Analysis showed Fe particles present in a red pigment underlying the gold layer, suggesting the presence of red ochre(seokganju), an iron oxide mineral. The yuso of the portrait of Shin Im(duksu 4846) is used a paper which contains gold as well as traces of Pb, Hg and Ag. The paper in the yuso for the portrait of Yi Seongwon(bongwan 10122) mainly consisted of Ag, indicating silver paper having been used in its fabrication. The inner paper in the yuso of the portrait of Yi Seogu(sinsu 1065) is a leather combined with Ag, Fe, and Br, according to chemical analysis. The FTIR of the leather sample reveals that the spectrum in the fingerprint region is nearly identical to that of sheepskin, indicating the yuso was made from gold-coated sheepskin.

A Study on the Patterns of Baekje Accessories (백제 장신구의 문양 분석)

  • Suh, Mi-Young
    • Journal of the Korean Society of Costume
    • /
    • v.58 no.8
    • /
    • pp.13-29
    • /
    • 2008
  • This study analyzes the patterns of Baekje accessories, including pattern kinds, symbolic meanings and pattern types. And also this study shows the characteristics of accessory patterns and gives a chance for reflecting upon the patterns of Baekje costume. This study is qualitative research using documentary records related with the accessories of Baekje and evacuated data. The results of the study are as the followings: First, the kinds of patterns were classified four groups, floral, animal, geometrical and other patterns. Also, the symbolic meanings of its were authority, prolificacy, longevity and protection against evil spirit. Floral pattern was expressed most frequently. Second, the types of patterns were classified two groups, individual and compound type. Both of them was variously expressed. Third, The major material was copper with gold. Most work techniques were boring and hammering. The patterns were the composition of floral or animal patterns as a main design and geometrical patterns as a section or border design. Forth, the expressive characteristics of Baekje accessory patterns were to prefer floral patterns and to express symmetrical composition of patterns, therefore the patterns of Baekje accessories showed their esthetic sense like elegance, mild, serenity, a sense of stability and the sense of balance. In conclusion, the expressive characteristics of Baekje accessory patterns would be expressed on the Baekje costume.

A Kinematic Analysis of Snatch Technique in Weight-Lifting (역도 인상동작의 운동학적 분석)

  • Moon, Young-Jin;Song, Joo-Ho;Kim, Ji-Seob
    • Korean Journal of Applied Biomechanics
    • /
    • v.14 no.2
    • /
    • pp.41-55
    • /
    • 2004
  • This study analyzed snatch technique in weight-lifting performed by female gold, silver, and copper medalists at the 75kg level in the 2002 Pusan Asian Games and obtained the following conclusions. 1. KSH used more extensor in the waist than those in ankles, knees, or hip joints during the second pull, So further training is required to manifest both each of joints and waist extensor effectively and thus for the line from shoulders through barbell to hip joints to form a smooth vertical pattern. 2. Contrary to those in other countries, Korean athlete KSH tended to be swift in starting but slow in the second pull section, showing less effectiveness in movement during the second pull; therefore, they must try to exert a swift movement in lockout. 3. KSH showed slowdown in the speed, which was a factor interfering with performance during second pull, despite the great maximum speed of moving barbell. It is important to use barbell sufficiently not to reduce the speed of vertical movement but rather to keep the speed increasing. 4. KSH, who kept doing inefficient movements such as failure to perform swift lockout after lifting the heel at the maximum angle of lower limbs, needs to reduce this meaningless extension of ankles, knees, or hip joints to exert energy effectively.

A Study on the Adaptability and Cytotoxicity of Porcelain Bonded Ni-Cr Alloy (도재소부용 Ni-Cr합금의 적합성과 세포독성에 관한 연구)

  • Choi, Boo-Byung;Shin, Myung-Chull
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.20 no.1
    • /
    • pp.7-17
    • /
    • 1982
  • In order to investigate the internal adaptability and cytotoxicity for porcelain fused to metal Ni-Cr alloy, two commercial alloys (Generic Gold-R alloy, Aalba Dent- Valloy)were employed and compared with new developed beryllium free Ni-Cr alloy (KIST-K alloy). After cementation of each crown to abutment die before and after ceramic bonding respectively, dies were mounted to epoxy resin and the internal space was measured between crown and die of each point on sagittal section. The results were as follows: 1) The results show that the space between the crown and the die was largest at the incisal edge, followed by the shoulder or the bevel and chamfer. The least was to be in the axial surface. 2) There were no significant difference in the adaptability of the compared alloys. 3) On day 2 of the experiment the cell multiplication was slightly inhibited by R and K alloys. However, observations taken at day 4 and 7 showed normal cell multiplication process compared to control group. 4) Alloy V exhibited the most severe cell toxicity among the alloys tested on day 2. By day 4 and 7 it showed a decrease level in toxicity, however it did not exhibit normal cell growth as compared to control group.

  • PDF

Growth of Heteroepitaxial InP/GaAs by selective liquid phase epitaxy (선택적 LPE방법에 의한 GaAs가판 상의 InP이종접합 박막의 성장)

  • Lee, Byung-Teak;An, Ju-Heon;Kim, Dong-Keun;Ahn, Byung-Chan;Nahm, Sahn;Cho, Kyoung-Ik;Park, In-Shik;Jang, Seong-Joo
    • Korean Journal of Materials Research
    • /
    • v.4 no.6
    • /
    • pp.687-694
    • /
    • 1994
  • Heteroepitaxial InP/GaAs layers were grown using the selective liquid phase epitaxy (SLPE) technique. It was observed that the optimum LPE conditions were $660^{\circ}C$ growth temperature, $5^{\circ}C$ supercooling, and $0.4^{\circ}C$/min cooling rate. Maximum expitaxial layer overgrowth (ELO) of 110-160$\mu \textrm{m}$ was obtained when the seed was aligned along (112) orientation. Initial melt-back of the substrate was observed but limited to the seed region so that flat In-Ga-As-P layers were grpwn throughout the GaAs substrates. The InP/GaAs heteroepitaxial structure could be obtained by growing an additional InP layer on top of the In-Ga-As-P layer.

  • PDF

A Study on the Surface Phenomena of Re-creational Gilt Layer by Conditions of Heat Treatment (열처리 조건에 따른 재현 도금층의 표면현상 연구)

  • Yang, Seok-Woo;Kim, Soo-Ki
    • Journal of Conservation Science
    • /
    • v.28 no.1
    • /
    • pp.29-37
    • /
    • 2012
  • This study discusses a mercury amalgam gilding technique and examines how the color, surface and section of the gilt layer changes as the condition of heat treatment with mercury amalgam gilt object is changed. Some previous studies have mentioned reasons for various colors on gilt bronze artifacts depending on gilding manufacture and environment. However, reason for reddish color with gold on the artifacts' surface brought on high temperature corrosion has yet to be discussed and analyzed. A methodology was found in representing the mercury amalgam gilding technique and heat treatment test. According to the result of the heat treatment test, in the conditions of higher temperature and longer time, the oxidized layer on the gilt layer was distributed more widely and in the part when the oxide layer was eliminated, the gilt layer with a reddish color was observed. Moreover, in the surface observation of the specimen on which yellow and reddish colors were agitated, the changing aspects of its surface condition differed by colors. When investigated the section, it was observed that the void density and size became larger. After a test, the surface components changed; the temperature of heat treatment increased, component ratio of Hg and Au decreased gradually but component ratio of Cu increased. In regard to the gilt layer, as the time was longer and the temperature became higher for the heat treatment, the component ratio of Au and Cu by layers tended to change in inverse proportion. It is concluded that gilding techniques and the burial environment can make a difference in the surface color of the gilt layer on the gilt bronze artifacts, the high temperature corrosion that occurs by heat after they are manufactured is also one of the factors that affects their surface color.

Analysis of Organic Components and Osteoinductivity in Autogenous Tooth Bone Graft Material

  • Kim, Young-Kyun;Lee, Junho;Kim, Kyung-Wook;Um, In-Woong;Murata, Masaru;Ito, Katsutoshi
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.35 no.6
    • /
    • pp.353-359
    • /
    • 2013
  • Purpose: Extensive research is actively ongoing for development of an ideal bone substitute that meets the gold standard. Tooth was selected as a donor site for evaluation of potentials in bone substitutes based on its similar chemical compositions to alveolar bone. Previous studies have evaluated inorganic components of autogenous tooth bone graft material (AutoBT) and osteoconductivity. In continuation from the previous studies, the current study was conducted for analysis of organic components and evaluation of osteoinductivity of AutoBT. Methods: Forty-six extracted teeth were collected from actual patients (Korea Tooth Bank, R&D Institute). Extracted teeth were processed into AutoBT and implanted in dorsal subcutaneous muscular tissues of 15 athymic mice. Biopsy samples were harvested at two, five, and eight weeks. The Bradford assay, sodium dodecyl sulphate polyacrylamide gradient gel, and western blotting were performed for investigation of organic contents of AutoBT. Results: Histology analyses showed signs of new bone formation as early as two weeks. Results of the Bradford assay indicated the existence of noncollagenous proteins (NCP). 0.29% (2.89 mg/g) of proteins were extracted by weight in the root portion of AutoBT; 0.02% (0.029 mg/g) and 1.79% (17.93 mg/g) of proteins were measured by weight in crown and block-form of AutoBT, respectively. However, recombinant human bone morphogenetic protein-2 was not observed in AutoBT. Conclusion: Within the limitation of the current study, AutoBT induced new bone formation by NCP embedded in dentin.

A study on Men's Trunks Designs Characterized by Chinese Letters (한자(漢字)를 응용한 남성 트렁크 디자인 연구)

  • Kim, Hye-Ree;Choi, Won-Kyung;Lee, Young-Sook
    • Fashion & Textile Research Journal
    • /
    • v.12 no.5
    • /
    • pp.574-581
    • /
    • 2010
  • Trunks like men's underpants are similar to boxer shorts and are made in both modern and traditional styles. Like boxer shorts, trunks cover the mid-section of the body (hence the name "trunk"). As the income level of the nation increases, men as well as women become interested in fashion expressing the individual's character, by not regarding fashion as simply wearing essential items to live in. Men's interest in fashion influences men's underwear designs which has been thought previously just as to be worn for living in. Nowadays, trunks are often worn as lounge wear in the household, therefore the need for sensual and characteristic trunks designs is required in the fashion market to meet the customer's new needs. In modern fashion designs, Chinese letters have been artistically presented and used in decorative fashion design regardless of its original meaning, generally embroidered in traditional costumes. Based on the fact that Chinese letters containing lucky meanings have traditionally been used, other Chinese letters meaning positive and prospective future can be adapted and weaved into men's trunks designs. Therefore, in this study, among many good meaning Chinese letters; four Chinese letters, 高(high), 金(gold), 義(justice), 愛(love), have been selected and applied in the trunks designs. The purpose of this study is to develop men's trunk designs using these Chinese letters which can be massively produced and sold in Asian countries which commonly understand the meaning of the Chinese letters as well as in South Korea.