• Title/Summary/Keyword: 주조물

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Interpretation of Making Techniques through Surface Characteristic Analysis and Non-destructive Diagnosis for the Gilt-bronze Seated Buddha in Dangjin Sinamsa Temple, Korea (당진 신암사 금동여래좌상의 표면특성 분석과 비파괴 정밀진단을 통한 제작기술 해석)

  • CHOI Ilkyu ;YANG Hyeri ;HAN Duru;LEE Chan Hee
    • Korean Journal of Heritage: History & Science
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    • v.56 no.1
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    • pp.100-116
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    • 2023
  • The Sinamsa Temple was built in the late Goryeo Dynasty and a gilt-bronze seated Buddha is enshrined in Geungnakjeon hall in the precinct. Various damages occurred in the gilt layer of the Buddha, such as peeling of the gilt layer and deteriorating gloss. In the study, the conservation conditions of the inside and outside on the statue were accurately investigated, and the making technique was interpreted through the material characteristics and non-destructive diagnosis of the statue. As a result, it is estimated that gold-gilding layer is pure gold, coloration pigment of black is carbon, green is malachite, atacamite and verdigris, red is red lead and cinnabar, respectively. In the deterioration evaluation, peeling, cracking, break out and exfoliation of the gilt layer are confirmed as damages, but the conservation condition is relatively wholesome. However, the gloss of the gilt layer is calculated to be wider in the poorer part than the maintenance part. The ultrasonic velocity of the statue was calculated to be 1,230 to 3,987 (mean 2,608) m/s and showed a relatively wide range. In infrared thermography, peeling was not confirmed, and no special bonding marks were found. In endoscope, some biological damage and corrosion were observed on the surface of the internal metal, and sealed artifacts were identified. Manufacturing technique based on the study, it is considered that the gilt-bronze seated Buddha was cast at once, and the mold was inverted to inject molten metal.

A STUDY OF ADDITIONAL VIBRATION EFFECT ON DENTIN BOND STRENGTH (진동이 상아질 결합력에 미치는 영향에 관한 연구)

  • Lee, Jin;Kim, Jung-Wook;Lee, Sang-Hoon;Kim, Chong-Chul
    • Journal of the korean academy of Pediatric Dentistry
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    • v.29 no.4
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    • pp.632-640
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    • 2002
  • The objective of the study was to apply the vibration technique to reduce the viscosity of bonding adhesives and thereby compare the bond strength and resin penetration into dentinal tubules achieved with those gained using the conventional technique. Eighty-eight noncarious extracted human permanent molar teeth were sectioned to remove the coronal enamel and were embedded in 1-inch PVC pipe with acrylic resin. The occlusal surfaces were placed so that the tooth and the embedding medium were at the same level to form one flat surface, and the samples were subsequently polished with silicon carbide abrasive papers. The samples were randomly assigned to 4 groups(n=22). On Group 1 and 2, Single Bond(3M-ESPE, St. Paul, USA) was used, and on Group 3 and 4, One-Step(Bisco Inc., Schaumburg, USA) was used, and each was applied according to its manufacturer's instructions. For Group 2 and Group 4, vibration was applied with ultrasonic scaler for 10 seconds, and the adhesive was light-cured for 10 seconds. Resin composite was condensed on to the prepared surface in two increments using a mold kit(Ultradent Products Inc., USA) and each was light-cured for 40 seconds. After 24 hours in tap water at room temperature the specimens were thermocycled, and shear bond strengths were measured with a universal testing machine(Instron 4465, Canton, USA). To investigate infiltration patterns of the adhesive materials, the surface of specimen was examined with scanning electron microscope. The results were as follows. 1. The shear bond strengths of vibration groups(Group 2, Group 4) were significantly greater than those of the non-vibration groups(Group 1, Group 3)(p<0.05). 2. The shear bond strengths of Single Bond and One-Step were not significantly different (p>0.05). 3. The vibration groups showed greater number of resin tags in tubules and lateral branches under SEM.

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Comparison of internal and marginal fit of crown according to milling order in a single machinable wax disc (단일 절삭가공용 왁스 디스크 내에서 순차적 절삭가공 순서에 따른 크라운의 내면 및 변연 적합도 비교)

  • Song, Jun-Beom;Lee, Jonghyuk;Ha, Seung-Ryong;Choi, Yu-Sung
    • The Journal of Korean Academy of Prosthodontics
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    • v.59 no.4
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    • pp.395-404
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    • 2021
  • Purpose. The purpose of present study was to evaluate the effect of changing structural stability of wax disc on the fit of prosthesis when the milling proceeded in order. Materials and methods. Prepared maxillary left first molar was used to fabricate a Ni-Cr alloy reference model. This was scanned to design crown and then wax pattern was milled, invested and cast to fabricate prosthesis. The wax patterns located in a row centrally within a single wax disc were set into a total of five groups ranging from WM1 group that was first milled to WM5 group that was last milled and the number of each group was set as 10. Silicone replica technique was used to measure the marginal gap, axial internal gap, line angle internal gap, occlusal internal gap. Data was evaluated with one-way ANOVA with significance level set at α = .05 and then Tukey HSD test was conducted for post analysis. Results. Marginal gap measured in each group, it was 40.41 ± 2.15 ㎛ in WM1 group, 40.44 ± 2.23 ㎛ in WM2 group, 39.96 ± 2.25 ㎛ in WM3 group, 39.96 ± 2.48 ㎛ in WM4 group, and 40.57 ± 2.53 ㎛ in WM5 group. No significant difference was found between groups. The significant difference between the groups was also not found in the axial internal gap, line angle internal gap, and occlusal internal gap. Conclusion. Internal and marginal fit of single crown to the sequential order of milling processing in the single machinable wax disc did not seem to be affected by the sequence.

The Comparison of the Retention of the Full Veneer Casted Gold Crowns with Different Implant Abutment Shapes and Types of Cements (임플란트 지대주 형태와 시멘트 종류에 따른 전부주조금관의 유지력 비교)

  • Jung, Jae-Wook;Kim, Jee-hwan;Kim, Sun-jai;Moon, Hong-suk;Shim, June-sung
    • Journal of Dental Rehabilitation and Applied Science
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    • v.25 no.4
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    • pp.403-415
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    • 2009
  • The purpose of the study is to establish the effect of different abutment shapes and types of cements on the retention of the full veneer casted gold crowns. Metal dies that has the similar shape with the implant abutment were manufactured using a short(5mm) and long(10mm) dies with different convergence angles. Metal dies and gold crowns, which were made from the metal dies, were cemented with Temp-bond, Temp-bond mixed with petroleum jelly, ZPC and Premier implant cement. After that, these were tested for tensile force at the point of separation. The effect of convergence angle changes of different cement types on the retention was studied as well as the effects of the cement type changes with different convergence angles on the retention. In addition, study about the marginal gap of Premier implant cement used for this experiment was conducted. The results are as followed under the in-vitro experimental limits; 1. The retention of the Temp-bond mixed with petroleum jelly decreased as the convergence angle increased, and the retention was weakest among the cements. 2. The retention of ZPC decreased as convergence angle increased. When convergence angle was 5 degrees, ZPC showed stronger retention than Premier implant cement. 3. Premier implant cement had the weakest retention when the convergence angle was 5 degrees but when the convergence angle was 10 degrees, it had the strongest retention. As the angle increased more than 10 degrees, the retention decreased. 4. Premier implant cement showed bigger marginal gap when the convergence angle was 5 degrees than 10 degrees under the experimental condition.

The Regional Classification of Tidal Regime using Characteristics of Astronomical Tides, Overtides and Compound Tides in the Han River Estuary, Gyeonggi Bay (천문조, 배조 및 복합조 특성을 이용한 경기만 한강하구 구역별 조석체계 분류)

  • Yoon, Byung Il;Woo, Seung-Buhm;Kim, Jong Wook;Song, Jin Il
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.27 no.3
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    • pp.149-158
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    • 2015
  • In this study, we investigate tidal wave propagation characteristics, and classify regional tidal regime using tidal form number considered distribution of astronomical tide, overtides, and compound tides in the Han River Estuary, Gyeonggi Bay. The characteristics of the tidal wave propagation in main channels show dominance of major tidal constituents (e.g., $M_2$, $S_2$, $N_2$, $K_1$ and $O_1$) contributing to the astronomical tide however, distinct increasing of shallow water (e.g., $M_4$) and long period (e.g., $MS_f$) components toward up-estuary. Using the characteristics of tidal form number to astronomical tide, overtides, and compound tides, the regional tidal regime could be assorted into three regions. Firstly, a dominance area of astronomical tide was presented from open sea to a front of Incheon Harbor (Yeomha channel) and to north entrance of Seokmo channel. The area between south and north entrance of Yeomha channel and Ganghaw north channel classified into zone of showing strong shallow water components. It could be separated into upper estuary, upstream the Singok underwater dam, showed dominance of shallow overtides (e.g., $M_4$ and $MS_4$) water and long-term compound tides (e.g., $MS_f$) larger magnitude than astronomical tide. The shallow water components was earlier generated in lower part (south entrance) of Yeomha channel have strong bottom by effect of shallower and narrower compared with Seokmo channel. Tidal asymmetries of upper estuary cause by a development of overtides and compound tides are mainly controlled by influence of man-made structure.

A comparison of the fidelity of various zirconia-based all-ceramic crowns fabricated with CAD/CAM systems (수종의 CAD/CAM 시스템으로 제작한 지르코니아 기반 완전도재관의 적합도 비교)

  • Kim, Sung-Jun;Jo, Kwang-Hun;Lee, Kyu-Bok
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.2
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    • pp.148-155
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    • 2009
  • Statement of problem: The interest in all-ceramic restorations has increased as more techniques have become available. With the introduction of machinable dental ceramics and CAD/CAM systems there is a need to evaluate the quality levels of these new fabrication techniques. Purpose: This study is to evaluate the crown fidelity(absolute marginal discrepancy and internal gap) of various zirconia-based all-ceramic crowns fabricated with different CAD/CAM(computer-assisted design/computer-assisted manufacturing) systems and conventional cast metal-ceramic crowns. Material and methods: A resin tooth of lower right second premolar was prepared. After an impression was taken, one metal master die was made. Then 40 impressions of metal master dies were taken for working dies. 10 crowns per each system were fabricated using 40 working dies. Metal-ceramic crowns were cast by using the conventional method, and Procera, Lava, and Cerec inLab crowns were fabricated with their own CAD/CAM manufactruing procedures. The vertical marginal discrepancies and internal gaps of each crown groups were measured on a metal master die without a luting agent. The results were statistically analyzed using the one-way ANOVA and Tukey's HSD test. Results: 1. Vertical marginal discrepancies were $50.6{\pm}13.9{\mu}m$ for metal-ceramic crowns, $62.3{\pm}15.7{\mu}m$ for Procera crowns, $45.3{\pm}7.9{\mu}m$ for Lava crowns, and $71.2{\pm}2.0{\mu}m$ for Cerec inLab crowns. 2. The Internal gaps were $52.6{\pm}10.1{\mu}m$ for metal-ceramic crowns, $161.7{\pm}18.5{\mu}m$ for Procera crowns, $63.0{\pm}10.2{\mu}m$ for Lava crowns, and $73.7{\pm}10.7{\mu}m$ for Cerec inLab crowns. Conclusion: 1. The vertical marginal discrepancies of, 4 crown groups were all within the clinically acceptable range($120{\mu}m$). 2. The internal gaps of LAVA, Cerec inlab, and metal-ceramic crowns were within clinically acceptable range except Procera crown($140{\mu}m$).

A Study on Park Gye-hyeong -Focusing on the Change of Romantic writing (박계형론 -낭만적 글쓰기의 변주를 중심으로)

  • Jin, Sun-Young
    • Journal of Popular Narrative
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    • v.25 no.2
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    • pp.247-275
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    • 2019
  • We hope that more diverse interests will arise in the novels by Park Gye-hyeong By looking at writers and works in time, we identified the key element of Park Gye-hyeong's novels as 'romantic'. Romantic nature of this time is lyrical, sentimental, spiritual, unrealistic and idealistic. Based on a romantic understanding of the world, the core sanction of the novel is love, focusing on feelings of sadness, and on the aspects of joy, separation, and pain that arise from loving relationships rather than the aspects of joy. Based on the feelings of grief, the novels end with failure, death and betrayal, thus embodying tragic romanticism. Before her marriage, Park Gye-hyeong's novels were love stories that revealed her longing for beautiful love based on sensibility. The idyllic world and longing for nature reveal a romantic world-view. Ultimately, it is a fictional worldview that the author seeks to despair and long for, and to find the sincerity and morality of love in an environment that does not. Park Gye-hyeong, who became a housewife, expressed that she wanted to write a piece that can give readers a sense of nostalgia by embodying "romance at a high level," not "sentimental." In subsequent works, physical relationships are treated as failures of love and spiritual relationships as the fruit of love, revealing the lofty spirituality, idealistic longing and religious nature of love. Park Gye-hyeong confessed her shame about her previous work when she published a new one after more than two decades of writing. And after more than two decades of reflection, her new novel had a new theme of "recovering destroyed humanity." However, the search for "humanity" in the two novels released after the write-off tends to be somewhat hasty at the end of the novel. The question of human nature, sin and forgiveness, is the next best thing to save as a way of life, rather than as a result of the intense inner agony and behavior of the characters within the narrative, and this also shows a sudden shift in religiousness at the end of the novel. Therefore, the romantic meaning of the superficial is superficial.

Politics of "Imagined Ethnicity" in World Music (월드뮤직에서 "상상된 민족"의 정치학)

  • Kim, Hee-sun
    • (The) Research of the performance art and culture
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    • no.22
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    • pp.223-252
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    • 2011
  • If we remember that modern world history has built systems of meaning through the concepts "difference," "different," and "other-ness" and has constructed new identity based on opposing hierarchy, music anthropology which tried to build "difference" between the west and the non-west was thoroughly west -centered, in the sense that it has perceived the heterogeneous symbolic systems among nations, as well as the barrier between the two cultures. On the other hand, world music, which has emerged as the most attractive field in culture industry and concert-art-market by crossing over global capitals, markets, and barriers, can be considered the most post-modernist and glocal. However, it is interesting to note that world music, which has been described as post-modern and glocal, has "difference" and "different" in its basis, just like the precepts for modern music anthropology (Meintjes 1990; Guilbault 1993; Taylor 1997; Frith 2000; Feld 1988). Furthermore, one can understand that the "different" and "difference," generally termed as being "non-western," are fundamentally based on ethnic or national imagination. In this sense it is interesting and important to examine such ethnic imagination in the "non-western ethnic musics" in music anthropology and in world music. Notwithstanding the attention paid and research made by music anthropologists, they have failed to elevate the "non-western ethnic musics" to become universally communicative, and these ethnic musics were reborn as "global" and "world music," through the process of "acculturation," "derivation," and "hybridization," with the west as major site for production and consumption. Meanwhile, the audience for world music, which did not exist before the birth of world music as a term, was now born as world music emerged. They are global populace who consume the musical "difference" and "imagined ethnicity," who through their consumption are constructing new social meanings including ethnicity, race, nation, and class identity. This study, by examining current discourse, performance, and process for the world music through media and field studies and scholarly debates, attempts to understand the production and consumption of "imagined ethnicity." This will also shed light on how "ethnicity" is created and consumed, and how this is involved in the process of world music.