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Influences of Cooling Atmosphere on the Whiteness in White Portland Cement (백 시멘트의 백색도에 미치는 냉각분위기의 영향)

  • 한기성;최상흘
    • Journal of the Korean Ceramic Society
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    • v.15 no.2
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    • pp.85-88
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    • 1978
  • Influence of cooling atmosphere on the whiteness in white portland cement was studied. The effective composition of gaseous medium of cooling atmosphere is desirable less than 0.5% of $O_2$ and 0.5~1.5% of CO. When theclinker is quenched in nitrogen atmosphere, the color of clinker becomes bright pink. In a weakly reducing gaseous medium or vacuum, the absence of oxygen brings defects in crystal and transformation in the coordination of iron, and as a result, whiteness is raised.

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Two Semantic Types of Korean Sluicing Constructions (슬루싱의 두 가지 의미 유형)

  • Wee, Hae-Kyung
    • Language and Information
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    • v.19 no.2
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    • pp.109-125
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    • 2015
  • In this study, I attempt to show two points about Korean sluicing. First, the semantic source of the null subject of the copula phrase in Korean sluicing is a null pronoun. This null subject pronoun may refer to either the antecedent indefinite individual or the antecedent event of the preceding clause. Second, depending on the presence/absence of postpositions in the remant wh-phrase, sluicing constructions are classified into two different semantic types: i) an equative clause and ii) a predicational clause.

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토러스 형상 돌기의 흡착특성 유한요소해석

  • Jo, Seong-San;Yang, Seung-Min
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.05a
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    • pp.179-184
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    • 2002
  • Adhesive contact characteristics of torus-shaped bumps, which are commonly used to reduce friction and stiction in hard disks, are analyzed to examine the applicability to the MEMS structure. The analysis is conducted with the finite element technique considering the adhesive force. Torus-shaped bumps of various rim and bump radii are analyzed. The jump-to-contact behavior, adhesion hysterisis, pull-off forces, contact region and pressure, and surface and subsurface stresses are presented and discussed. Analysis results in the absence of adhesive force are also presented to identify the effect of adhesive force.

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Saddle Embolism Caused by Left Atrial Myxoma -A Case Report- (안장 색전증을 유발한 좌심방 점액종 -수술 치험 1례-)

  • 송정근
    • Journal of Chest Surgery
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    • v.28 no.3
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    • pp.316-319
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    • 1995
  • Systemic emboli occur in approximately one-third of patients with cardiac myxoma. Embolization is common because of the friability of the tumor and intracardiac location. Embolic episodes in young patients with normal sinus rhythm should arouse suspicions of cardiac myxoma in the absence of active endocarditis. We present one case of 17 years old girl having saddle embolism combined with left atrial myxoma. We planned staged operation. First, the emergency thromboembolectomy of aortic bifurcation was performed through bilateral transfemoral approach with use of Forgaty catheter. One week later, the extirpation of myxoma was successfully done with ECC.

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Microstructure of Perigynium and Achene Surfaces of Carex sect. Sideroxtictae in Korea

  • Oh, Yong-Cha
    • Journal of Plant Biology
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    • v.39 no.2
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    • pp.137-144
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    • 1996
  • Scanning electron microscope revealed several taxonomically useful characters in the perigynium and achene epidermis of sect. Siderosticatae (Carex siderosticta, C. ciliatomarginata and C. okamotoi). Mocroscopic characters such as perigynium shape, hair presence or absence, beak shape, nodule situation in perigynium, achene shape, cell wall and silica cone in achene were useful in Carex at the species levels. A key was presented on the basis of features obtained from the examinations.

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Environmental Factors Related to Low (Back Pain of Advisor in Gumi Industrial Complex) (관리감독자의 작업장 근무환경과 요통과의 관계 (구미지역 사업장을 중심으로))

  • 차상은;박상래;김정동;김상렬;김선엽
    • Journal of the Korean Society of Safety
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    • v.9 no.1
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    • pp.165-173
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    • 1994
  • The objective of this study were to the distribution of low back pain prevalence rates, and to Identify and compare risk indicators in cases with low back pain presence and low back pain absence. The results were as follows : 1. Of the respondents, 34.4% reported lob-related LBP 2. There were statistically significant relationships between job satisfaction, time spent standing, time spent sitting, vibration, noise.

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Some Peculiarities of Photo-structural Transformations in Amorphous Chalcogenide Glassy Semiconductor Films

  • Prikhodko, O.;Almasov, N.;Korobova, Natalya
    • Journal of information and communication convergence engineering
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    • v.9 no.5
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    • pp.587-590
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    • 2011
  • The absence of deep traps for electrons in the spectrum of $As_{40}Se_{30}S_30$ localized states films obtained by ion sputtering was determined. Bipolar drift of charge carriers was found in amorphous $As_{40}Se_{30}S_30$ films of chalcogenide glassy semiconductors, obtained by ion-plasma sputtering of high-frequency, unlike the films of these materials obtained by thermal evaporation.

The Problems and Measures in Design and Construction of LPS based on KS (한국산업규격에 의한 피뢰설비 설계 및 시공의 문제점과 대책)

  • Lee, Ki-Hong;Lee, Taek-Soeb
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.05a
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    • pp.346-348
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    • 2005
  • This paper presented problems occurred in design and construction of LPS(Lightning Protection System) based on the new KS(Korea Standard), and proposed various solution for those. Imperfect KS, poor data on lightning characters in Korea lack of train for engineer, immature SPD engineering and absence of LPS design sample for various buildings are main problems. We suggested that comprehensive measures attending every persons and organizations relevant LPS are needed to solve the problems.

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Poultry Disease and Its Prevention (가금질병과 방역 개선책)

  • 오경록
    • Korean Journal of Poultry Science
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    • v.23 no.2
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    • pp.99-106
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    • 1996
  • Because of the imminent market opening of livestock and poultry products, Korean poultry industry is faced an influx of contagious diseases from abroad. Due to the increasing trend of intensive and automatic poultry farming, the risks of catching various poultry epidemics are ever more increasing. For the prevention of poultry epidemics, the principles of biosecurity should be observed rather strictly. In addition, regular checking to confirm the presence or absence of latent diseases through serological test, post-mortem examination, and laboratory test, should be carried out routinely. Finally, all kinds of stress factors should be minimized to keep the flock healthy and productive, so that they can achieve their maximum genetic potential.

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Recognition of Driving Direction & Obstacles Using Neural Network (신경망을 이용한 차량의 주행방향과 장애물 인식에 관한 연구)

  • Kim, Myung-Soo;Yang, Sung-Hoon;Lee, Seok
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.10a
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    • pp.341-343
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    • 1995
  • In this paper, an algorithm is presented to recogniz the driving direction of a vehicle and obstacles in front of it based on highway road image. The algorithm employs a neural network with 27 sub sets obtained from the road image as its input. The outputs include the direction of the vehicle movement and presence or absence of obstacles. The road image, obtained by a video camera, was digitized and processed by a personal computer equipped with an image processing board.

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