• Title/Summary/Keyword: Structure Stability

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A study on the bone thickness of midpalatal suture area for miniscrew insertion (미니스크류 식립 부위로서 정중 구개봉합부 골의 두께에 관한 연구)

  • Kyung, Seung-Hyun
    • The korean journal of orthodontics
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    • v.34 no.1 s.102
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    • pp.63-70
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    • 2004
  • The midpalatal suture area has some advantages for supporting miniscrews : it has no specific anatomical structure, it is composed of thick cortical bone, and covered with attached gingiva. So it is suitable area for inserting miniscrews. However, the midpalatal suture area appears thinner when seen in ceph. As a result, Clinicians can misunderstand that inserting miniscrews cause the problem, both the risk of perforation and the decrease of stability. The purpose of this article is measuring the vertical bone thickness of the midpalatal suture area for inserting miniscrews. The total of 25patient (male : 13, female : 12), who are in their twenties, were taken CT. The vertical bone thickness of the midpalatal suture area was measures from the transverse section of CT. As a result, We reached a conclusion from the differences of each area. It is as follows: 1. There is no significant difference between the thickness of male group and that of female group. 2. In coronal section, Bone thickness becomes thinner from the midpalatal suture to Left & Right side, in sagittal section, Bone thickness becomes thinner from incisive foramen to PNS. 3. The area that is within 3mm of left and right from the midpalatal suture area transversely and within 25mm backward from the incisive foramen sagittaly is enough for inserting miniscrews.

Music Therapy Interventions for Prevention of Suicidal Ideation (자살 충동 예방을 위한 음악치료적 접근)

  • Lee, In Yong
    • Journal of Music and Human Behavior
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    • v.3 no.2
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    • pp.45-58
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    • 2006
  • Recently many treatment strategies have been developed to prevent suicidal ideation as it is increasing. Various community facilities and university centers are carrying out research to develop efficient treatment programs. This study examined how music can be used therapeutically for a case who is going through severe suicidal ideation. Various music therapy techniques are utilized including song psychotherapy, music and imagery and role play instrumental improvisation. A woman with severe depression for seven one-hour session. Both quantitative and qualitative data were collected to examine the changes in the suicidal ideation. As results, there were lots of changes in the client's attitude towards life through exploring inner world. Much of stability and sense of security were gained and emotional hardship was resolved in the process of therapy. The client was able to structure future plans productively as the suicidal ideation was reduced. In the process of role play instrumental improvisation, music allowed her to express issues regarding relationships with others, attitudes and in other areas as well. Music was used "as therapy" and solved many repressed emotions related to the trauma including psychological inhibition, tension, helplessness, lack of energy. Further music was able to bring the "false" ego with "true ego". The study implies that various psychotherapeutic interventions can alleviate depression and reduce suicidal ideation.

Preparation of Talc-Silica Composites by Controlling Surface Charge Behavior (표면전하 거동 조절을 이용한 탈크-실리카 복합체의 제조)

  • Yun, Ki-Hoon;Park, Min-Gyeong;Moon, Young-Jin;Lee, Dong-Kyu
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.1
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    • pp.116-124
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    • 2017
  • A plate-type inorganic pigment complex was manufactured in a manner that treats the surface of the complex by adjusting zeta potential between talc, an inorganic pigment used as a material for color cosmetics, and hydrophobic silica. Talc, which is usually used in the prescription of color cosmetics, is a plate-type, white-colored inorganic substance with good application and spreadability to skin. Furthermore, it features excellent dispersibility and extensibility as well as outstanding heat tolerance, light stability, and chemical resistance. In general, silica contributes to durable makeup and stabilized formulation. This paper covers a process of manufacturing an inorganic pigment complex, where hydrophobic silica was applied to the surface of talc by using differences in zeta potential after the surface charges of talc and hydrophobic silica had been adjusted with cationic and anionic surfactants, respectively. The resulting inorganic pigment complex was composed of talc whose surface is coated hydrophobic silica to the thickness of $1{\mu}m$ or less, which developed an effective hydrophobic property. Zeta potential was measured to analyze the surface charge of an inorganic pigment, and FT-IR, used to check the functional group of a surfactant, was applied to treat the surface of the pigment. The surface of the inorganic pigment complex was observed employing SEM, EDS, and FIB, while its structure was confirmed with XRD and FT-IR.

Estimating the compound risk integrated hydrological / hydraulic / geotechnical uncertainty of levee systems (수문·수리학적 / 지반공학적 불확실성을 고려한 제방의 복합위험도 산정)

  • Nam, Myeong Jun;Lee, Jae Young;Lee, Cheol Woo;Kim, Ki Young
    • Journal of Korea Water Resources Association
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    • v.50 no.4
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    • pp.277-288
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    • 2017
  • A probabilistic risk analysis of levee system estimates the overall level of flood risk associated with the levee system, according to a series of possible flood scenarios. It requires the uncertainty analysis of all the risk components, including hydrological, hydraulic and geotechnical parts computed by employing MCMC (Markov Chain Monte Carlo), MCS (Monte Carlo Simulation) and FOSM (First-Order Second Moment), presents a joint probability combined each probability. The methodology was applied to a 12.5 km reach from upstream to downstream of the Gangjeong-Goryeong weir, including 6 levee reaches, in Nakdong river. Overtopping risks were estimated by computing flood stage corresponding to 100/200 year high quantile (97.5%) design flood causing levee overflow. Geotechnical risks were evaluated by considering seepage, slope stability, and rapid drawdown along the levee reach without overflow. A probability-based compound risk will contribute to rising effect of safety and economic aspects for levee design, then expect to use the index for riverside structure design in the future.

The Current State and Implementation of Music Therapy for Adults With Intellectual Disabilities (국내 성인지적장애인 음악치료 중재 현황)

  • Oh, Ji Eun
    • Journal of Music and Human Behavior
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    • v.13 no.2
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    • pp.17-30
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    • 2016
  • This study aimed to examine the current state of music therapy for adults with intellectual disabilities (ID) by conducting a survey of music therapists. Completed surveys from 32 certified music therapists were included for analysis. The questionnaire was composed of 38 items that asked about the participants' background, work environment and music therapy implementation experience (including assessment, goal establishment, intervention strategy and difficulties). The results of the study showed that music therapy for adults with ID was practiced in diverse facilities. Enhancing social interaction was the most frequently set goal by music therapists, whereas facilities mostly required the music therapy services for emotional stability. Also, instrument playing was used most among music activities, and musical structure was considered most when choosing music for therapy. Among the influential institutional factors, characteristics of the facility were considered most frequently, and the level of functioning was the most considered in terms of client-related factors. To advance the effective use of music therapy interventions with adults with ID, development of music therapy assessment tools and more active communication with facility staff were also suggested when working with this population.

Analysis of wet chemical tunnel oxide layer characteristics capped with phosphorous doped amorphous silicon for high efficiency crystalline Si solar cell application

  • Kang, Ji-yoon;Jeon, Minhan;Oh, Donghyun;Shim, Gyeongbae;Park, Cheolmin;Ahn, Shihyun;Balaji, Nagarajan;Yi, Junsin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.406-406
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    • 2016
  • To get high efficiency n-type crystalline silicon solar cells, passivation is one of the key factor. Tunnel oxide (SiO2) reduce surface recombination as a passivation layer and it does not constrict the majority carrier flow. In this work, the passivation quality enhanced by different chemical solution such as HNO3, H2SO4:H2O2 and DI-water to make thin tunnel oxide layer on n-type crystalline silicon wafer and changes of characteristics by subsequent annealing process and firing process after phosphorus doped amorphous silicon (a-Si:H) deposition. The tunneling of carrier through oxide layer is checked through I-V measurement when the voltage is from -1 V to 1 V and interface state density also be calculated about $1{\times}1012cm-2eV-1$ using MIS (Metal-Insulator-Semiconductor) structure . Tunnel oxide produced by 68 wt% HNO3 for 5 min on $100^{\circ}C$, H2SO4:H2O2 for 5 min on $100^{\circ}C$ and DI-water for 60 min on $95^{\circ}C$. The oxide layer is measured thickness about 1.4~2.2 nm by spectral ellipsometry (SE) and properties as passivation layer by QSSPC (Quasi-Steady-state Photo Conductance). Tunnel oxide layer is capped with phosphorus doped amorphous silicon on both sides and additional annealing process improve lifetime from $3.25{\mu}s$ to $397{\mu}s$ and implied Voc from 544 mV to 690 mV after P-doped a-Si deposition, respectively. It will be expected that amorphous silicon is changed to poly silicon phase. Furthermore, lifetime and implied Voc were recovered by forming gas annealing (FGA) after firing process from $192{\mu}s$ to $786{\mu}s$. It is shown that the tunnel oxide layer is thermally stable.

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Cobalt(II) Complex of 1,2-Bis(2,2'-bipyridyl-6-yl)ethane. Crystallization Process and Structural Analysis of Two Shapes of Crystals (1,2-비스(2,2'-디피리딜-6일)에탄의 코발트 착물. 두 가지 형태의 결정화 과정 및 구조 분석적 접근)

  • Park, Sung-Ho;Yoo, Kyung-Ho;Jung, Ok-Sang
    • Analytical Science and Technology
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    • v.12 no.5
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    • pp.421-427
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    • 1999
  • Two shapes of crystals have been isolated by the interdiffusion of $Co(NCS)_2$ dissolved in methanol with 1,2-bis(2,2'-bipyridyl-6-yl)ethane (bbpe) dissolved in chloroform. The two crystals have been elucidated as $trans-Co^{II}(NCS)_2(bbpe)$ and $trans-Co^{II}(NCS)_2(bbpe){\cdot}2CHCl_3$, by X-ray crystallography, elemental analysis, IR, and thermal analysis. The two molecular structures are very similar except for the absence or presence of chloroform solvate molecules. The bbpe ligand coordinates to the cobalt(II) ion in an open-ended tetradentate mode, resulting in discrete mononuclear cobalt(II) complex. The cobalt atom adopts a typical octahedral arrangement with six nitrogen donating atoms with two NCS groups in trans positions. A significant solid-to-solid phase transition occurs presumably due to the change of conformationally flexible bbpe ligand. The formation of both crystals oeeurs in a successive two-step process, the formation of $trans-Co^{II}(NCS)_2(bbpe)$ and its transformation into $trans-Co^{II}(NCS)_2(bbpe){\cdot}2CHCl_3$. The thermal stability and favorable formation of the solvate crystals may be ascribed to the interaction between S atom of NCS group and Cl of chloroform.

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Improvement in Mechanical Properties of Cast Magnesium Alloy through Solid-solution Hardening and Grain Refinement (고용 강화 및 결정립 미세화를 통한 마그네슘 합금 주조재의 기계적 물성 향상)

  • Kim, Sang-Hoon;Moon, Byoung-Gi;You, Bong-Sun;Park, Sung-Hyuk
    • Journal of Korea Foundry Society
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    • v.37 no.6
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    • pp.207-216
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    • 2017
  • This study investigated the effects of the addition of Zn, Ca, and SiC on the microstructure and mechanical properties of Mg-Al alloys. The tensile properties of homogenized Mg-xAl (x = 6, 7, 8, and 9 wt.%) alloys increased with increasing Zn content by the solid-solution strengthening effect. However, when the added Zn content exceeded the solubility limit, the strength and ductility of the alloys decreased greatly owing to premature fracture caused by undissolved coarse particles or local melting. Among the Mg-xAl-yZn alloys tested in this study, the AZ74 alloy showed the best tensile properties. However, from the viewpoints of the thermal stability, castability, and tensile properties, the AZ92 alloy was deemed to be the most suitable cast alloy. Moreover, the addition of a small amount (0.17 wt.%) of SiC reduced the average grain size of the AZ91 alloy significantly, from $430{\mu}m$ to $73{\mu}m$. As a result, both the strength and the elongation of the AZ91 alloy increased considerably by the grain-boundary hardening effect and the suppression of twinning behavior, respectively. On the other hand, the addition of Ca (0.5-1.5 wt.%) and a combined addition of Ca (0.5-1.5 wt.%) and SiC (0.17 wt.%) increased the average grain size of the AZ91 alloy, which resulted in a decrease in its tensile properties. The SiC-added AZ92 alloy exhibited excellent tensile properties (YS 125 MPa, UTS 282 MPa, and EL 12.3%), which were much higher than those of commercial AZ91 alloy (YS 93 MPa, UTS 192 MPa, and EL 7.0%). The fluidity of the SiC-added AZ92 alloy was slightly lower than that of the AZ91 alloy because of the expansion of the solid-liquid coexistence region in the former. However, the SiC-added AZ92 alloy showed better hot-tearing resistance than the AZ91 alloy owing to its refined grain structure.

Relation between Tuffier's Line and Spondylolisthesis (척추전방전위증과 Tuffier's line 높이와의 상관관계)

  • Kim, Han-Kyum;Hong, Soon-Sung;Yom, Sun-Kyu;Jin, Eun-Seok;Jung, Hae-Chan
    • The Journal of Churna Manual Medicine for Spine and Nerves
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    • v.3 no.2
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    • pp.37-42
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    • 2008
  • Objectives : One of the most important cause of spondylolisthesis is it's epidemiological structure and L5's stability takes a significant role. The purpose of this study is to assess the difference of the Tuffier's line among of Spondylolythesis patients. Methods : We analyzed the Anterior view of lumbar spine checked at erect position on 60 patients who had been diagnosed as spondylolythesis. We investigated the Tuffier's Line on X-ray film. Results and Conclusions : Age distribution was 15 to 66 and the average was 47.81. Men were 19 cases(31.6%) and women were 41 cases(68.4%). Compared to men, women were more exposed to spondylolisthesis and for the age distribution, 50's showed the biggest portion. Group of normal people showed proportion of 14.3% at L4, 44% at L4/5 and 41.7% at L5 each. And group of patients showed proportion of 48.4% at L4, 35% at L4/5 and 51.6% at L5 each. Comparing these results, significance probability was 0.004(<0.05) which was significant. As the results of comparing the relation between L4/5 and L5/S1 patients, Normal group showed average of 3.33 which were close to L4/5. When there are spondylolisthesis at L4/5, averege was 3.33, placed at lower part of the vertebra body. When there are spondylolisthesis at L5/S1, averege was 3.566, placed between lower part of the veterbra body of L4 and L4/5. The p value of Normal group and L4/5 spondylolisthesis patient group was 0.022(p<0.05) which was significant. But the p value of Normal group and L5/S1 spondylolisthesis patient group was 0.0239 which was not significant. Also p value of L4/5 spcndylolisthesis patient group and L5/S1 spondylolisthesis patient group was 0.721 which was also not significant.

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Synthesis and Characterization of The Electrolessly Deposited Co(Re,P) Film for Cu Capping Layer (무전해 도금법으로 제조된 Co(Re,P) capping layer제조 및 특성 평가)

  • Han, Won-Kyu;Kim, So-Jin;Ju, Jeong-Woon;Cho, Jin-Ki;Kim, Jae-Hong;Yeom, Seung-Jin;Kwak, Noh-Jung;Kim, Jin-Woong;Kang, Sung-Goon
    • Korean Journal of Materials Research
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    • v.19 no.2
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    • pp.61-67
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    • 2009
  • Electrolessly deposited Co (Re,P) was investigated as a possible capping layer for Cu wires. 50 nm Co (Re,P) films were deposited on Cu/Ti-coated silicon wafers which acted as a catalytic seed and an adhesion layer, respectively. To obtain the optimized bath composition, electroless deposition was studied through an electrochemical approach via a linear sweep voltammetry analysis. The results of using this method showed that the best deposition conditions were a $CoSO_4$ concentration of 0.082 mol/l, a solution pH of 9, a $KReO_4$ concentration of 0.0003 mol/l and sodium hypophosphite concentration of 0.1 mol/L at $80^{\circ}C$. The thermal stability of the Co (Re,P) layer as a barrier preventing Cu was evaluated using Auger electron spectroscopy and a Scanning calorimeter. The measurement results showed that Re impurities stabilized the h.c.p. phase up to $550^{\circ}C$ and that the Co (Re,P) film efficiently blocked Cu diffusion under an annealing temperature of $400^{\circ}C$ for 1hr. The good barrier properties that were observed can be explained by the nano-sized grains along with the blocking effect of the impurities at the fast diffusion path of the grain boundaries. The transformation temperature from the amorphous to crystal structure is increased by doping the Re.