• Title/Summary/Keyword: Destruction

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A Study on the Variations of Stability and Heat Budget in the Planetary Boundary Layer at Kimhae (김해지방의 지표경계층내의 열수지 및 안정도 변화에 관한 연구)

  • 박종길;이화운;김유근;이순환
    • Journal of Korean Society for Atmospheric Environment
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    • v.13 no.2
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    • pp.103-113
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    • 1997
  • The research described in this paper was conducted to estimate the stability and heat budget in planetary boundary layer (PBL) at Kimhae. The upper air observation was carried out during period from 3 Februsry 1993 to 5 February 1993 at Kimhae. The surface observation data used the one during period from 1 April 1994 to 31 March 1995. The maximum height of inversion layer observed at Kimhae was 310 m. Destruction of the inversion was simultaneously occurred at the surface and the mid-layer (200 $\sim$ 300 m), however the origin of destruction is different each other. The surface inversion is destructed by surface heating owing to growing radiation in surface but disappearance of the mid-layer inversion is related to the upper cold air movement.

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Management of apicomarginal defect in esthetic region associated with a tooth with anomalies

  • Meharwade, Vinayak Venkoosa;Shah, Dipali Yogesh;Mali, Pradyna Prabhakar;Meharwade, Vidya Vinayak
    • Restorative Dentistry and Endodontics
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    • v.40 no.4
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    • pp.314-321
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    • 2015
  • Tooth related factors such as palatoradicular groove can be one of the causes for localized periodontal destruction. Such pathological process may result in apicomarginal defect along with inflammation of pulp. This creates challenging situation which clinician must be capable of performing advanced periodontal regenerative procedures for the successful management. This case report discusses clinical management of apicomarginal defect associated with extensive periradicular destruction in a maxillary lateral incisor, along with histopathologic aspect of the lesion.

A Methodology to Determine Persistence of Objects from Procedural Program (절차지향 프로그램으로부터 객체의 지속성을 결정하기 위한 방법론)

  • Choi, Jeong-Ran;Lee, Moon-Kun
    • Journal of KIISE:Software and Applications
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    • v.29 no.3
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    • pp.133-144
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    • 2002
  • This paper presents a methodology to determine safe persistence of objects from C code during reengineering process. The methodology consists of five steps: the static information methodology, reflection, instantiation, and the refinement. The steps assist to a reengineer to decide appropriate construction and destruction points of an object during its life cycle. Further the steps guarantee safe and consistent interactions among objects.

Failure Mode Analysis of Mo-tip EFA Cold-Cathode in CRT Spot-knocking Process (CRT의 Spot-knocking 공정에 있어서 몰리브텐 팁 전계 방출 소자 냉응극의 고장 형태 분석)

  • Ju, Byeong-Kwon;Kim, Hoon;Park, Jong-Won;Kim, Nam-Soo;Kim, Dong-Ho;Lee, Yun-Hi
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.8
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    • pp.414-418
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    • 2001
  • Failure modes of Mo-tip FEA were investigated in detail as a preliminary study for the application of Mo-tip FEA to the CRT electron-gun as a cold cathode. It was identified that the destruction of Mo-tip FEA was originated from reflowing of arc-current during the spot-knocking process followed by secondary arc between gate electrode and cathode substrate. In order to prevent Mo-tip FEA from destruction due to arc-current, two kinds of methods were suggested, that is one is to provide the by-pass of the reflow current and the other is to install a current limiter in the path of gate connection line.

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Experimental Study on Assumption of Compressive Strength of Recycled Aggregate Concrete by Nondestructive Test to Practical Building (재생골재 콘크리트 실구조물의 비파괴 시험에 의한 압축강도 추정에 관한 실험적 연구)

  • Song, Young-Chan;Shim, Jong-Woo;Jun, Myoung-Hoon;Lee, Sea-Hyun;Lee, Do-Heun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.125-128
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    • 2006
  • As the ministry of construction and transportation established quality standards for recycled aggregate in August, 2005, the consumption of recycled aggregates is expected to be increased in construction fields in the future. Thus the relations between compressive strength of general concretes and that of recycled aggregate concretes which are applied to actual structures are attempted to investigate through non-destruction testing method. Presently Schmitt-Hammer test method is that concrete compressive strength is predicted by measuring surface hardness of concretes, and is well known as the most convenient and simply operated method among many non-destruction testing methods. In this study, cylinder specimen and mock-up were constructed using recycled aggregate concretes made by the first class recycled coarse aggregates and recycled fine aggregates specified in KS F 2573 (recycled aggregate for concrete), and compressive strength of hardened concrete of middle ages was evaluated.

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A Study of Application of the Undrained Shear Strength of the Soft Clay in the Area of Slope Failure (사면파괴 지역의 연약점토에 대한 비배수 전단강도 적용에 관한 연구)

  • Jeong, Jin-Ho;Lee, Sung-Rok;Lim, Chang-Kyu
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.681-686
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    • 2006
  • This study is to examine slope activity safety ratio on the strength of the natural sample or soil collected through field test in the slope activity region during destruction happened in the course of soil-relocating work planned for ground improvement under strict supervision at the house-building site, using Bishop's slope analysis method and investigate relationship between slope analysis theories and actual destruction so as to compare determining method of clean water of soil essential for slope activity analysis and accuracy of resulting value of clean water of soil.

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Damage Analysis of High Voltage Motor for Intake Pump (취수 펌프용 고압전동기(6.6 kV, 3,800 kW)의 소손원인 분석)

  • Oh, Min-Hwan;Lee, Eun-Chun;Hong, Sung-Taek;Lee, Sang-Gun
    • Proceedings of the KIEE Conference
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    • 1999.07c
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    • pp.1324-1326
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    • 1999
  • This paper demonstrates the insulation-destruction of high-voltage-motors for intake pump. To analyze the causes of damage in motors, electrical, mechanical and environmental fiery-development were investigated. The insulation-destruction of high-voltage-motors are generally due to the fiery-stress by void where composite materials such as mica/epoxy are used. But this paper shows that electrical and mechanical stresses can be the main reason of the damage, too.

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Program Development for Vibration Performance Evaluation of Powder Transfer Equipment (분립체 이송장치의 진동 성능평가를 위한 프로그램 개발)

  • Lee Hyoung Woo;Park No Gill
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.10
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    • pp.170-179
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    • 2004
  • A vibration model of powder transfer equipment is developed by the lumped parameter method. A Powder transfer equipment does surging motion, bouncing motion and pitching motion. Motion equation becomes decoupling and removed vibration exciting source about pitching motion, and therefore designers presented the optimum design plan to be able to do adjustment with motion trajectory of powder transfer equipment. That is, way for design to be able to do motion trajectory of powder transfer equipment through change of design element as installation position and direction of motor, driving speed, mass unbalance, stiffness coefficient and installation position of support coil spring is presented. The design results, powder transfer equipment were able to know that fatigue destruction does not occur, and the reason is because maximum stress working on a basket structure is more very than fatigue strength small.

Study on the Change of Physical Properties with Silica Contents in Solution Styrene-Butadiene Rubber (SSBR)/Silica Composites

  • Kim, Tae Yeop;Won, Sung Yeon;Kang, Shin Hye;Cho, Ur Ryong
    • Elastomers and Composites
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    • v.52 no.1
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    • pp.17-21
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    • 2017
  • The optimum mixing conditions of silica and silane containing rubber composites were evaluated by investigating the properties of rubber composites prepared with a silica composition of 10, 20, 40, 60, and 80 g, respectively. The crosslinking rate decreased with increasing silica content, with he promoters being adsorbed on the silica surface with in the rubber composite. As a result, the increase in crosslinking time resulted in the destruction of the silica structure. The increase of the bound rubber content due to the destruction of the silica structure inhibited the chain motion of the polymer molecules and reduced the cohesion of the silica itself. Finally, the increase of silica content showed the increase of hardness, tensile strength, and storage modulus of rubber composites.

Program Development for Vibration Performance Evaluation of Powder Transfer Equipment

  • Lee, Hyoung-Woo;Ryu, Jeong-Hyeon;Park, Noh-Gill
    • International Journal of Precision Engineering and Manufacturing
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    • v.7 no.2
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    • pp.60-65
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    • 2006
  • A vibrational model of powder transfer equipment based on the lumped parameter method was developed, in which the operating motion consists of surging, bouncing, and pitching. After decoupling the equation of motion, the vibrational excitation source of the pitching motion was removed. So the designers are able to plan the optimum design to adjust the motion trajectory of the powder transfer equipment. That is, a procedure to adjust the motion trajectory of powder transfer equipment by changing design specifications such as the installation position, the direction of the motor, the driving speed, the mass unbalance, the stiffness coefficient, and the installation position of the support spring, is presented in this paper. The powder transfer equipment manufactured according to the results of this study did not suffer fatigue destruction, since the maximum stress on the basket structure was sufficiently small.