• Title, Summary, Keyword: Super stability

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A New Substituent Constant $σ^{c+}4_s$;a Fit for π-Participation in Modified Hammett-Brown Equation

  • 조정호;신정휴
    • Bulletin of the Korean Chemical Society
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    • v.17 no.4
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    • pp.347-348
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    • 1996
  • A set of substituent constants, σc+, has been widely used comparing the stability of carbocation in super acid condition. Plotting of 13C chemical shifts of cationic carbon (Δδc+) against σc+ constants yields an excellent correlation with a good correlation coefficient (r=0.999) for a cyclopentyl cation system. But these σc+ constants show poor linearity in norbornenyl cations that well known to show homoallylic stabilization in a cationic condition. We calculated the new substituent constant, σc+π, and found that the new substituent constants give an excellent correlation in π- and πσ-participating cation systems.

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Brake Lining Can be Applied to Super High Speed Vehicle

  • Nakano, Satoru;Maejima, Takashi
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • pp.1305-1306
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    • 2006
  • A new material was developed to achieve improvement of heat durability, improvement of wear resistance, stability of friction coefficient and reduction in aggression to counterpart, because it is difficult to maintain braking properties by using currently available materials in the train wagons used for high-speed transportation. As a result, the new material showed a stable wear resistance even in the speed range of 350km/h, where improvement was also confirmed in reduction of aggression to counterpart material by more than approximately 10%. This development was adopted for the brake lining in the Taiwan High Speed Rail project.

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CONTINUITY OF AN APPROXIMATE JORDAN MAPPING

  • Lee, Young-Whan
    • Communications of the Korean Mathematical Society
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    • v.20 no.3
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    • pp.505-509
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    • 2005
  • We show that every $\varepsilon-approximate$ Jordan functional on a Banach algebra A is continuous. From this result we obtain that every $\varepsilon-approximate$ Jordan mapping from A into a continuous function space C(S) is continuous and it's norm less than or equal $1+\varepsilon$ where S is a compact Hausdorff space. This is a generalization of Jarosz's result [3, Proposition 5.5].

Towards Super Thin OLED TVs: Barix Thin Film Encapsulation of Glass and Flexible Displays

  • Xi, Chu;Lin, Steven;Rosenblum, Marty;Visser, R.J.
    • 한국정보디스플레이학회:학술대회논문집
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    • pp.1634-1637
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    • 2008
  • We will discuss encapsulation of OLEDs on both flexible and rigid glass substrates. Accelerated testing at 6CC/90RH and 85C/85RH is compared and acceleration factors for OLED and Calcium test samples are discussed.We have tested the stability and performance of our barrier coating to much higher temperatures: up to 140 C. Water Vapor Transmission rates at temperatures from 60 to 140 C are presented. Rates and methods for low cost manufacturing on a large scale are analysed.

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Investigation on mechanics performance of cable-stayed-suspension hybrid bridges

  • Zhang, Xin-Jun
    • Wind and Structures
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    • v.10 no.6
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    • pp.533-542
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    • 2007
  • The cable-stayed-suspension hybrid bridge is a cooperative system of the cable-stayed bridge and suspension bridge, and takes some advantages and also makes up some deficiencies of both the two bridge systems, and therefore becomes strong in spanning. By taking the cable-stayed-suspension hybrid bridge, suspension bridge and cable-stayed bridge with main span of 1400 m as examples, the mechanics performance including the static and dynamic characteristics, the aerostatic and aerodynamic stability etc is investigated by 3D nonlinear analysis. The results show that as compared to the suspension bridge and cable-stayed bridge, the cable-stayed-suspension hybrid bridge has greater structural stiffness, less internal forces and better wind stability, and is favorable to be used in super long-span bridges.

A Study on Fuzzy Control Simulator of Naturally Circulated Boiler (자연 순환식보일러의 퍼지제어 모사기 개발에 관한 연구)

  • Kim, Kwang-Sun;Kim, Sam-Un
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.4
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    • pp.543-554
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    • 2000
  • The engineering equations, which have been used in many engineering companies, were employed for the dynamic modelling part in order to develop the naturally circulated boiler simulator. The fuzzy algorithm, which is similar to the algorithm of making decision by the human being, was developed for the boiler simulator controller and its simulated variables were compared with those of classical PID simulations to verify the stability and the effectiveness of fuzzy controller. The simulator is for the naturally circulated boiler and the main components are the furnace, the drum, the super heater, and the economizer. The combustion and thermal radiation dominant equations were used within the furnace and the mass conservation and the energy rate balance equations were employed for the drum part. The heat transfer rates were calculated using the logarithmic mean temperature differences both for the super heater and for the economizer. The simulations are very useful to understand the boiler operations and the engineering design of the main components. The main program was developed under the PC window condition by linking the fuzzy controller to the main boiler program using the Visual C++ language. The various operational conditions such as the abrupt changes of load, the changes of water supply pipes and the diameter of drum were simulated.

The Structural Design of Tianjin Goldin Finance 117 Tower

  • Liu, Peng;Ho, Goman;Lee, Alexis;Yin, Chao;Lee, Kevin;Liu, Guang-lei;Huang, Xiao-yun
    • International Journal of High-Rise Buildings
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    • v.1 no.4
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    • pp.271-281
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    • 2012
  • Tianjin Goldin Finance 117 tower has an architectural height of 597 m, total of 117 stories, and the coronation of having the highest structural roof of all the buildings under construction in China. Structural height-width ratio is approximately 9.5, exceeding the existing regulation code significantly. In order to satisfy earthquake and wind-resisting requirements, a structure consisting of a perimeter frame composed of mega composite columns, mega braces and transfer trusses and reinforced concrete core containing composite steel plate wall is adopted. Complemented by some of the new requirements from the latest Chinese building seismic design codes, design of the super high-rise building in high-intensity seismic area exhibits a number of new features and solutions to professional requirements in response spectrum selection, overall stiffness control, material and component type selection, seismic performance based design, mega-column design, anti-collapse and stability analysis as well as elastic-plastic time-history analysis. Furthermore, under the prerequisite of economic viability and a series of technical requirements prescribed by the expert review panel for high-rise buildings exceeding code limits, the design manages to overcome various structural challenges and realizes the intentions of the architect and the client.

Dispersion Modeling Methodology for Hazardous/Toxic Gas Releases from Chemical Plant Facilities (화학장치설비의 유해독성가스 누출에 대한 분산모델링 방법론)

  • Song Duk-Man
    • Journal of the Korean Institute of Gas
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    • v.1 no.1
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    • pp.73-80
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    • 1997
  • This study was performed to develop the dispersion modeling methodology for quantitative prediction of the hazard distance or toxic buffer distance by comparing 10-min average, 30-min average, and 1-hr average maximum ground-level concentration with $Cl_2$ regultaion concentration, IDLH and ERPG-3 concentration for hazardous toxic gas, $Cl_2$ releases from the storage tank of the chemical plant facilities. For this dispersion modeling, the source term model, dispersion model, meteorological and topographical data are incorporated into the SuperChems model, and then the effects of the atmospheric stability, wind speed, and surface roughness length changes on the maxum ground-level concentration were estimated.

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An Analysis of Factors Affecting the Variation of GDP Gap by a Decomposition Method (GDP갭 분해기법을 이용한 변동요인 분석)

  • Chang, Youngjae
    • The Korean Journal of Applied Statistics
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    • v.27 no.3
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    • pp.387-396
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    • 2014
  • The GDP gap (also called the output gap) is the difference between potential GDP and actual GDP. Potential GDP is the maximum sustainable output that is achieved when the resources (labor and capital) are used to capacity. Central banks pursuing price and employment stability consider the output gap as an informative variable for monetary policy since the output gap could be regarded as a proxy of demand-supply imbalances. In this paper, the GDP gap of Korea is decomposed following the filtering method in the previous research, and major factors that affect the variation of GDP gap are investigated based on the decomposed series. The analysis results by the Super Smoother algorithm used in Fox et al. (2003)and Fox and Zurlinden (2006) are found consistent with theory. Much of the variation of nominal GDP gap is explained by Total Factor Productivity(TFP) gap, which is the change of productivity due to recent technological innovation and environmental change. It is also found that variation of terms of trade significantly affects the GDP gap of Korea due to its high dependency on international trade; however, the effect of the domestic price is not negligible like other countries.

In doped ZTO 기반 산화물 반도체 TFT 소자의 CuCa 전극 적용에 따른 특성 변화 및 신뢰성 향상

  • Kim, Sin;O, Dong-Ju;Jeong, Jae-Gyeong;Lee, Sang-Ho
    • Proceedings of the Korean Vacuum Society Conference
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    • pp.167.2-167.2
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    • 2015
  • 고 이동도(~10 cm/Vs), 낮은 공정온도 및 높은 투과율 등의 특성을 갖는 산화물 반도체는 저 소비전력, 대면적화 및 고해상도 LCD Panel에 적합한 재료로서 현재 일부 Mobile Panel 및 TFT-LCD Panel의 양산에 적용되고 있으나, 향후 UHD급(4 K, 8 K)의 대형, 고해상도 Panel에의 적용을 위해서는 30 cm2/Vs 이상의 고 이동도 재료의 개발 및 저 저항 배선의 적용에 따른 소자 신뢰성의 개선이 필요하다. Cu는 대표적인 저 저항 배선 재료로 일부 양산에 적용되고 있으나, Cu 전극과 산화물 반도체의 계면에서 Cu원자의 확산 및 Cu-O 층의 형성에 의한 소자 특성 저하의 문제가 있다. 본 연구에서는 고 이동도의 In doped-ZTO계 산화물 반도체를 기반으로 채널 층과 Cu source-Drain layer의 계면에서의 Cu element의 거동 및 TFT 소자 특성과의 상관관계를 고찰하고, 계면에 형성된 Cu-O layer에 대해 높은 전자 친화도를 갖는 Ca element를 첨가에 의한 TFT 소자 특성의 변화를 관찰하였다. 본 연구에서는 이러한 효과로 인한 소자 신뢰성의 향상을 기대하였으며, 우선 In doped-ZTO 채널 층에 Cu와 CuCa 2at% source-drain을 적용한 TFT 특성을 확인하였다. 그 결과, Cu는 Field-effect mobility: ~17.67 cm2/Vs, Sub-threshold swing: 0.76 mV/decade 및 Vth:, 4.40 V의 결과가 얻어졌으며 CuCa 2at%의 경우 Field-effect mobility: ~17.84 cm2/Vs, Sub-threshold swing: 0.86 mV/decade 및 Vth:, 5.74 V의 결과가 얻어졌다. 소자신뢰성 측면에서도 Bias Stress의 변화량 ${\delta}Vth$의 경우 Cu : 4.48 V에 대해 CuCa 2at% : 2.81 V로 ${\delta}Vth$:1.67 V의 개선된 결과를 얻었다.

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