• Title/Summary/Keyword: Dent

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Multiple calcifying hyperplastic dental follicles: A case report

  • Aydin, Ulkem;Baykul, Timucin;Yildirim, Benay;Yildirim, Derya;Bozdemir, Esin;Karaduman, Ayse
    • Imaging Science in Dentistry
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    • v.43 no.4
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    • pp.303-308
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    • 2013
  • This report describes a 31-year-old female patient with six impacted teeth. The crowns of the impacted teeth were surrounded with cyst-like lesions with a mixed internal structure and well-defined cortical borders. Microscopic examination of the specimen obtained from the follicle of the left mandibular third molar tooth revealed loose to moderately dense collagenous connective tissue with abundant calcified material and sparse epithelial islands. A diagnosis of multiple calcifying hyperplastic dental follicles was made.

한국산 산개구리 (Rana dybowskii Gruenther)의 뇌하수체에 관한 연구: II. 활동기와 동면기의 미세구조 비교

  • 김창환;김우갑;한성식;김지현
    • The Korean Journal of Zoology
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    • v.24 no.1
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    • pp.38-57
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    • 1981
  • Cardell, Jr. (1964)는 도룡뇽의 뇌하수체 전염에서 5가지의 분비세포를 구분하였으며 Dent와 Gupta (1967), 그리고 Iturrza (1964)는 영원류에서 5가지 분비세포를 구분하여 보고한 바 있다. 또 Doerr-Schott (1965)는 개구리에서 5가지 분비세포를, Mira-Moser (1969, 1970)는 6가지의 분비세포와 한가지의 무과립세포를 구분하였다. Shinkawa등 (1972)도 역시 7가지 cell type을 구분하였다. Shinkawa와 Nakai (1972)는 참개구리에서 역시 7가지 cell type을, 그리고 이들이 선정한 3 cell type에서 ACTH를 분비한다는 사실을 보고 하였다. 이에 본 연구자들은 산개구리를 재료로 하여 우선 동면기의 것을 실험하였던 바 7가지 cell type을 구분한 바 있고, 다시 활동기의 것을 재료로하여 세포내 소기관의 변화를 관찰하였는데 여기서 몇가지 차이점을 보고하는 바이다.

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Quality Improvement of Smart UAV Rotor-Hub Part Through Gas Nitriding of Maraging Steel (가스질화처리 적용을 통한 스마트무인기 머레이징강 로터허브 부품 품질개선)

  • Lee, Myeong Kyu;Choi, Seong Wook;Kim, Jai Moo
    • Journal of Aerospace System Engineering
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    • v.8 no.2
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    • pp.33-39
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    • 2014
  • Feathering spindle is one of the critical parts of the rotor system in the Smart Unmanned Aerial Vehicle(SUAV) that it was manufactured with special material, Maraging C300. During the initial ground and tie-down flight tests of the SUAV, surface of the feathering spindle contacting to the needle-roller bearings showed excessive wear and dent due to high vibrating loads transferred from the rotating blades. Gas nitriding process was applied to the bearing contact surface of the feathering spindle to increase surface hardness so as to improve the surface defects. This paper briefly presents the gas nitriding process adopted and the spindle quality improvements including wear and corrosion resistance.

A Fundamental Study on the Lateral Impact Problems of Tubular Members (원통부재의 횡충돌에 관한 기초적 연구)

  • Lee Sang-Gab;Chung Young-Gu
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1995.10a
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    • pp.234-241
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    • 1995
  • Offshore structures are exposed to higher probability of collision with ship because of their limited mobility. In general, the consequence of the collision is reported to be relatively small and it is desirable to consider minor collisions in the design stage. It is important to have a comprehensive understanding of the dynamic responses of a tubular, their main member, under collision to design offshore structure against possible accidents. It is needed to estimate the probable extent of damage of a tubular, depth of dent, affected by the time history of impact load in ender to design a tubular strong enough for collision. In this paper, dynamic behaviors of a tubular due to the lateral impact are investigated through the numerical simulations with hydrocode DYNA3D, a three dimensional elasto-plastic large deformation impact contact problem analyzing program.

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A Study on the Application of High Manganese Austenitic Steel Sheet to Automobile Parts (고망간 오스테나이트계 강판의 자동차 부품 적용성 연구)

  • Jung, Y.I.;Chae, S.H.;Kim, S.Y.;Hong, S.H.;Lim, J.D.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.393-396
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    • 2009
  • The mechanical properties, press formability and texture of a TWIP steel were investigated. This steel combines both high strength and high ductility due to so called TWIP effect which are related to the microstructural changes. The formation of twins during deformation leads to an increase of its mechanical properties. In this study, the texture and mechanical properties evolutions of a TWIP steel subjected to tensile tests and press trials at room temperature were investigated in relation to the feasibility of the application to automotive body parts.

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Study on Experimental Selection of Parameters in Laser Scattering Mechanism and Analysis of Laser Scattering Patterns in Solar Cell Wafer (레이저 산란 메커니즘 매개변수의 실험적 선정 및 태양전지 웨이퍼의 레이저산란패턴 분석에 관한 연구)

  • Kim, Gyung-Bum
    • Journal of the Semiconductor & Display Technology
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    • v.10 no.2
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    • pp.7-12
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    • 2011
  • In this paper, a laser scattering mechanism are designed to detect micro defects such as dent, scratch, pinhole, etc. Its influential parameters are experimentally selected and scattering patterns of micro defects have been analyzed for silicon wafer in solar cell. As a result of experiments, scattered lights are rather increased in wafer surface with micro defects, in comparison to no micro ones. Scattering parameters are optimally selected for obtaining robust and high quality laser scattering images of micro defects. It is shown that scattered light components are linearly increased according to the increase of micro defect sizes, and the depth of micro-defects give a large influence on optical deflection.

Effects of Administration of 2,2'-Azobis(2-amidinopropane) Dihydrochloride(AAPH) on Liver Function in Rats 1. Clinical Signs and Blood Chemical Values (2,2'-Azobis (2- amidinopropano) Dihydrochloride(AAPH)의 투여가 쥐의 간기능에 미치는 영향 1. 임상증상 및 혈액 화학치 소견)

  • 강정부;손호상;김철호
    • Journal of Veterinary Clinics
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    • v.15 no.1
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    • pp.75-78
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    • 1998
  • This study was performed to estimate the clinical signs and changes of biochemical parameters in rats with hepatic injury induced by the administration of 2, 2'-azobis(2- amidinopropane)dihydrochloride (AAPH) . Minor behavioral change, brittleness of skin hair and decreased volume of water and feed intake were observed in ra% 2 hours after AAPH administration compared to control group. Concentration of serum albumin showed lower than that of control group. However, concentration of total bilirubin has shown higher than that of control group. As time goes on, . serum LDH activity increased significantly compared to control group, but senun CPK activity did not change compared to control group. Passive hemanglutination of $\alpha $-fetoprotein was negative in all the treaDent groups and control group.

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유기용매에 의한 CYP2E1의 유도발현 : 단백질형성 효율의 증가에 따른 조절규제기전

  • ;Raymond F. Novak
    • Toxicological Research
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    • v.9 no.2
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    • pp.153-158
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    • 1993
  • Pyridine and acetone are efficacious inducers of CYP2E1 in both rats and rabbits. The response in the elevation of CYP2E1 levels, changes in CYP2E1 mRNA levels, and enhanced translational processing of hepatic CYP2E1 mRNA during the early phase of CYP2E1 induction by the solvents pyridine and acetone were examined. Time-depen-dent incease in CYP2E1 levels occurred at early times (6-24h) following a single dose of pyridine treatmene, as assessed by Western immunoblot analysis, whereas the levels in CYP2E1 mRNA transiently decreased at 12h post-treatment, returning to the level present in untreated animals.

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Distribution Characteristics of Residual Compressive Stresses Induced by Shot-peening in the Aircraft Structural Material (항공기 구조용 재료의 쇼트피닝에 의한 압축 잔류응력의 분포 특성)

  • 이환우;박영수
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.5
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    • pp.149-157
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    • 2004
  • Residual stresses can have a significant influence on the fatigue lives of structural engineering components. For the accurate assessment of fatigue lifetimes a detailed knowledge of the residual stress profile is required. Significant advances have been made in recent years fur obtaining accurate and reliable determinations of residual stress distributions. These include both experimental and numerical methods. The purpose of this study is to simulate peening process with the help of the finite element method in order to predict the magnitude and distribution of the residual stresses in accordance with the parameters, which are, e.g. shot velocity, shot diameter, shot impact angle, shot shape, distance between two impinging shots, and material parameters.

Group Key Agreement From Signcryption

  • Lv, Xixiang;Li, Hui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.12
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    • pp.3338-3351
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    • 2012
  • There is an intuitive connection between signcryption and key agreement. Such a connector may lead to a novel way to construct authenticated and efficient group key agreement protocols. In this paper, we present a primary approach for constructing an authenticated group key agreement protocol from signcryption. This approach introduces desired properties to group key agreement. What this means is that the signcryption gives assurance to a sender that the key is available only to the recipient, and assurance to the recipient that the key indeed comes from the sender. Following the generic construction, we instantiate a distributed two-round group key agreement protocol based on signcryption scheme given by Dent [8]. We also show that this concrete protocol is secure in the outsider unforgeability notion and the outsider confidentiality notion assuming hardness of the Gap Diffie-Hellman problem.