• 제목/요약/키워드: super stability

검색결과 153건 처리시간 0.028초

GENERALIZED STABILITIES OF CAUCHY'S GAMMA-BETA FUNCTIONAL EQUATION

  • Lee, Eun-Hwi;Han, Soon-Yi
    • 호남수학학술지
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    • 제30권3호
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    • pp.567-579
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    • 2008
  • We obtain generalized super stability of Cauchy's gamma-beta functional equation B(x, y) f(x + y) = f(x)f(y), where B(x, y) is the beta function and also generalize the stability in the sense of R. Ger of this equation in the following setting: ${\mid}{\frac{B(x,y)f(x+y)}{f(x)f(y)}}-1{\mid}$ < H(x,y), where H(x,y) is a homogeneous function of dgree p(0 ${\leq}$ p < 1).

Numerical investigation on the wind stability of super long-span partially earth-anchored cable-stayed bridges

  • Zhang, Xin-jun;Yao, Mei
    • Wind and Structures
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    • 제21권4호
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    • pp.407-424
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    • 2015
  • To explore the favorable structural system of cable-stayed bridges with ultra-kilometer main span, based on a fully self-anchored cable-stayed bridge with 1400 m main span, a partially earth-anchored cable-stayed bridge scheme with the same main span is designed. Numerical investigation on the dynamic characteristics, aerostatic and aerodynamic stability of both two bridge schemes is conducted, and the results are compared to those of a suspension bridge with similar main span, and considering from the aspect of wind stability, the feasibility of using partially earth-anchored cable-stayed bridge in super long-span bridges with ultra-kilometer main span is discussed. Moreover, the effects of structural design parameters including the length of earth-anchored girder, the number of auxiliary piers in side span, the height and width of girder, the tower height etc on the dynamic characteristics, aerostatic and aerodynamic stability of a partially earth-anchored cable-stayed bridge are analyzed, and their reasonable values are proposed. The results show that as compared to fully self-anchored cable-stayed bridge and suspension bridge with similar main span, the partially earth-anchored cable-stayed bridge has greater structural stiffness and better aerostatic and aerodynamic stability, and consequently becomes a favorable structural system for super long-span bridges with ultra-kilometer main span. The partially earth-anchored cable-stayed bridge can achieve greater stiffness and better wind stability under the cases of increasing the earth-anchored girder length, increasing the height and width of girder, setting several auxiliary piers in side span and increasing the tower height.

정적 및 동적안전성이 우수한 SUPER concrete 100MPa 활용 부잔교 개발 (Development of static and dynamic stability utilizing superior SUPER concrete 100MPa pontoon)

  • 임형주;윤식재;이상희
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2016년도 춘계학술대회
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    • pp.135-136
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    • 2016
  • 초고강 콘크리트를 활용한 부잔교는 강재부잔교에 비해 부식의 염려가 없어 내구성과 동적안전성이 우수하고, 일반 콘크리트에 비해 경량구조물로 건현확보가 유리하다. 현재 국내 연구개발 결과 SUPER concrete는 100MPa까지는 강섬유의 배합없이 일반골재만으로 배합이 가능하여 고부식성 환경의 항만구조물의 내구성에 적합한 강도이다. 부잔교는 상부슬래브에 작용하는 차량(DB-18) 또는 군집하중(5kN/m2)과, 외부 벽체 및 하부슬래브에 작용하는 파력의 수평과 양력성분을 견디도록 하여야 한다. 설계 파랑은 인천 연평도지역을 대상으로 50년 빈도 유의파와 주기에 해당하는 파력을 산정하여 X,Y축 위치에 따라 수평 및 양력성분을 재하하였다. 전체계 해석시 부잔교는 연직방향 경계조건이 없는 상태에서 부력 산정이 가능하도록 기하비선형 및 시간이력해석기법을 응용하였다(Strand 7). 부잔교 슬래브에 대해서는 실물모형실험을 통해 DB-18하중 재하에 따른 안전성을 확인하였다.

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Stability Enhancement of Super-RENS Readout Signal

  • Kim, Joo-Ho;Lee, Yong-Woon;Hwang, Wook-Yeon;Shima, Takayuki;Chung, Chong-Sam
    • 정보저장시스템학회논문집
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    • 제3권3호
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    • pp.123-125
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    • 2007
  • We report the readout stability improvement results of super-resolution near field structure (Super-RENS) writeonce read-many (WORM) disk at a blue laser optical system. (Laser wavelength 405nm, numerical aperture 0.85) By using diffusion barrier structure (GeSbTe sandwiched by GeN) and high transition temperature recording material ($BaTiO_3$), material diffusion of phase change layer and recording mark degradation were greatly improved during high power (Pr=2.0mW) readout process up to $1{\times}10^5$ times.

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300HP급 초고속 전동기용 회전체의 동력학적 해석 및 설계 (Design and Dynamic Analysis of Rotor for 300HP Class Super High-Speed Motor)

  • 이용복;이희섭;김승종;김창호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.16-18
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    • 2007
  • The Super High-Speed Motor is a turbo machine which operates at high speed, so air foil bearings suit their purpose as bearing elements. The rotordynamic stability was predicted using the numerical analysis of air foil bearings. From this study, the stability of rotor of the Super High-Speed Motor was confirmed by campbell diagram and logarithmic decrement.

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고층 아파트 외관 슈퍼그래픽의 시지각적 특성 및 평가 성향에 관한 연구 (A Study on Visual Characteristic & Evaluation of the Super Graphic of High-raised Apartment Housing)

  • 최석창;양소진;유창균;이청웅
    • 한국주거학회논문집
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    • 제14권6호
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    • pp.147-154
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    • 2003
  • This study examines and analyzes the current status, characteristics and properties of Super-Graphic as a visual element with Super Graphic designed on the wall of apartment housing, typifies them and explains the preference and evaluative structure by each type. The results of this study are as follows: According to color environment of Super-Graphic, N-tone colors are 21.4% and YR-tone colors are 14.5%. In the whole distribution, cold color tone is 41.4% and warm color tone is 37.2%. In the brightness, 72.9% of the entire Super Graphic use high brightness and in the saturation, 51.2% show low saturation, achromatic colors are 21.4% and high saturation is 16.5%. As a result of conducting SD test to analyze the preference of Super-Graphic, 'wonderful' is most negative variable, followed by 'heterogeneous', 'splendid', 'romantic' variety'. Positive variables are 'monotone', 'stable' and 'calm'. As a result of factor analysis to reveal the evaluative structure of Super Graphic image based on the above results, five factors including brightness, saturation, stability, harmony and ordered are extracted and it is considered that these are important variables to be reflected in designing Super Graphic in future.

Mechanics feasibility of using CFRP cables in super long-span cable-stayed bridges

  • Zhang, Xin-Jun
    • Structural Engineering and Mechanics
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    • 제29권5호
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    • pp.567-579
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    • 2008
  • To gain understanding of the applicability of CFRP cables in super long-span cable-stayed bridges, by taking a 1400 m cable-stayed bridge as example, mechanics performance including the static behavior under service load, dynamic behavior, wind stability and seismic behavior of the bridge using either steel or CFRP cables are investigated numerically and compared. The results show that viewed from the aspect of mechanics performance, the use of CFRP cables in super long-span cable-stayed bridges is feasible, and the cross-sectional areas of CFRP cables should be determined by the principle of equivalent axial stiffness.

UPCU의 안정성 검토 및 초정밀 위치결정 (Stability Analysis and Ultra-Precision Positioning for UPCU)

  • 김우진;김재열;윤성운;장종훈;김유홍;최철준
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2005년도 춘계학술대회 논문집
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    • pp.48-53
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    • 2005
  • The world, coming into the 21st century, is preparing a new revolution called a knowledge-based society after the industrial society. The interest of the world is concentrated on information technology, nano-technology and biotechnology. In particular, the nano-technology of which study was originally started from an alternative for overcoming semiconductor micro-technology. It can be applied to most industry subject such as electronics, information and communication, machinery, chemistry, bioengineering, energy, etc. They are emerging into the technology that can change civilization of human beings. Specially, ultra precision machining is quickly applied to nano-technology in the field of machinery. Lately, with rapid development of electronics industry and optic industry, there are needs for super precision finishing of various core parts required in such related apparatuses. This paper handles stability of a super precision micro cutting machine that is a core unit of such a super precision finisher, and analyzes the results depending on the hinge type and material change, using FEM analysis. By reviewing the stability, it is possible to achieve the effect of basic data collection for unit control and to reduce trials and errors in unit design and manufacturing.

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진공 플라즈마 처리를 통한 초소수성 표면 제작 및 특성 평가 (Fabrication of Super Water Repellent Surfaces by Vacuum Plasma)

  • 나종주;정용수;김완두
    • 대한기계학회논문집A
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    • 제32권2호
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    • pp.143-147
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    • 2008
  • Super-hydrophobic surfaces showed that contact angle of water was higher than 140 degrees. That surface could be made several methods such as Carbon nano tubes grown vertically, PDMS asperities arrays, hydrophobic fractal surfaces, and self assembled monolayers coated by CVD and so on. However, we fabricated super-hydrophobic surfaces with plasma treatments which were very cost efficient processes. Their surfaces were characterized by static contact angles, advancing, receding, and stability against UV irradiation. Optimal surfaces showed static contact angles were higher than 150 degrees. Super-hydrophobic property was remained after UV irradiation for one week.

울산시 초고층 아파트 거주자의 주거만족도 (Residential Satisfaction of Households living in Super-High Rise Apartment in Ulsan)

  • 김선중;김수정
    • 대한가정학회지
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    • 제37권3호
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    • pp.101-110
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    • 1999
  • The purpose of this study was to invesitigate the residential satisfaction of households living in super-high rise apartment. The questionnarles were collected from 244 residents living in super-high rise apartment above 20 stories located in Ulsan. Used statistical techniques were frequency, one-way ANOVA. The major findings were as follows: 1) Although the respondents were dissatisfied with super-high rise apartments, they chose present dwelling due to public transportation, easy access to work, and other community facilities. 2) Households who have more educated husband and wife and younger child were less satisfied with current dwelling. 3) The attrative features of super-high rise apartment were interior facilities, exterior environment, and social relations, While the negative features were interior environment, safety, and psychological stability.

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