• Title/Summary/Keyword: anchoring effect

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A Study on Surface Liquid Crystal Alignment an Anchoring Strangth of Polystyrene Surfaces in Nematic Liquid Crystal (네마틱액정에 있어서 폴리스타이렌막의 표면액정배향효과 및 결합강도에 관한 연구)

  • Seo, Dae-Shik
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1600-1602
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    • 1996
  • We have investigated the anisotropic dispersion force effects for surfaces alignment of liquid crystals (LCs) on rubbed polystyrene (PS) surfaces by unidirection. In microphotographs an of the textures, we obtained the nematic (N) LCs are shown to align in both direction parallel and perpendicular to the rubbing for region up to medium rubbing, however to align in the direction perpendicular to the rubbing for strong rubbing region. We suggest that the anisotropic dispersion force is very important rather than macro-surface groove effect to uniform alignment of LCs. We also measured the temperature dependence of extrapolation length of 5CB on rubbed PS surfaces for strong rubbing. It is shown that the polar anchoring strength of 5CB is very weak on rubbed PS surface compared to the rubbed polyimide (PI) surface.

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A Study on Characteristics of Surface Modified Polyimide Film by Wet Process (습식 표면개질 처리된 폴리이미드 필름 표면의 특성에 관한 연구)

  • Koo, S.B.;Lee, H.K.
    • Journal of the Korean institute of surface engineering
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    • v.39 no.4
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    • pp.166-172
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    • 2006
  • Metallized Polyimide films are extensively used as base materials in microelectronics, optical and automotive applications. However it is difficult to deposit metals on those because of their structural stabilities. In this work, polyimide films are modified by a wet process with alkalinemetalhydroxide and additives to introduce functional groups. The surface molecular structures of polyimide are investigated using X-ray photoelectron spectroscopy(XPS), fourier transform infrared reflection spectroscopy(FTIR-ATR), atomic force micro-scopic(AFM). XPS spectra and FTIR spectra show that the surface structure of polyimide is converted into potassium polyamate. AFM image and AFM cross-sectional analyses reveal the increased roughness on the modified surface of polyimide films. As a result, it is shown that the adhesion strength between polyimide surface and electroless nickel layer is increased by the nano-anchoring effect.

Cell Gap Dependent Electrode-Optic Characteristics of Fringe-Field Switching Mode using a Liquid Crystal with Negative Dielectric Anisotropy (유전율 이방성의 음인 액정을 이용한 Fringe-Field Switching mode의 cell gap 변화에 따른 전기광학 특성)

  • 정송희;김향율;이종문;이승희
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.10
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    • pp.914-922
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    • 2003
  • The FFS (fringe-field switching) mode was known to exhibit both a wide viewing angle and high transmittance, especially when using a liquid crystal with negative dielectric anisotropy. We have studied cell gap-dependent electrode-optic characteristics of the FFS mode using the LC with negative dielectric anisotropy. In case of a small cell gap of 2 ${\mu}$m, the transmittance at the center of pixel and common electrodes is relatively low because effect of surface anchoring that holds the LC to the initial state is larger than that in a large cell gap of 4 .urn such that the LCs in those regions cannot rotate enough. However, in case of a large cell gap of 4 .urn, the effect of surface anchoring becomes relatively small so that the LCs at the center of pixel and common electrode can be twisted enough by applied voltage, giving rise to high transmittance. Therefore, we can conclude that the light efficiency is dependent on the cell gap.

Fixed Versus Floating Interest Rates in Shipping Finance: A Behavioral Finance Perspective

  • Kim, Wu-Seok
    • Journal of Navigation and Port Research
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    • v.45 no.5
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    • pp.259-275
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    • 2021
  • This study analyzed the decision-making process in ship finance for the choice between fixed and floating interest rates using behavioral finance theories. Results confirmed that causes and background of decision-making processes could be explicitly explained by the framework of behavioral finance theories. This study also determined whether decisions were irrational. A case-study research was applied as the methodology. Decision-making data on ship finance collected through narrative and questionnaire responses were analyzed and evaluated using behavioral finance theories. Theories of behavioral finance used in the analysis and research of this study included availability heuristic, anchoring effect, and opportunity cost theory. Narrative and survey responses were clearly explained by theories of behavioral finance. It was found that a shipping company suffered additional losses owing to decisions that included behavioral finance errors. Behavioral finance theories largely influenced the decision-making process of choosing between a fixed interest rate and a floating interest rate. Shipping finance decisions related to interest rate selections could be clearly explained by behavioral finance theories. Errors related to behavioral finance could result in irrational decisions. Thus, managers who are responsible for shipping finance should remain vigilant toward any behavioral finance errors when making shipping finance decisions.

Synthesis of Well-Defined Block Copolymer Dispersants with (2-Dimethylamino)ethyl Methacrylate and Oligo(ethylene oxide)methyl Ether Methacrylate via ATRP for Dispersing Copper Phthalocyanine Pigment (Copper Phthalocyanine Pigment의 분산을 위한 (2-Dimethylamino)ethyl Methacrylate와 Oligo(ethylene oxide)methyl Ether Methacrylate를 포함하는 잘 규정된 블록 공중합체형 분산제의 원자 이동 라디칼 중합을 이용한 합성)

  • Kim, Eun-Hee;Kim, Bong-Soo;Jung, Ki-Suk;Kim, Jin-Goo;Paik, Hyun-Jong
    • Polymer(Korea)
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    • v.36 no.1
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    • pp.104-110
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    • 2012
  • The dispersion of pigment particles is important because it is capable of increasing the color strength, contrast, and transmittance of color-LCD products. Pigment dispersion properties are very important factors for the quality of LCD color filters. The chemical structure of polymeric dispersants for pigment is important to improve dispersion stability and prevent aggregation or flocculation of pigment in organic or aqueous systems. Polymeric dispersants should contain both anchoring group that interacts with pigment surface and stabilizing group that provides steric stabilization. Moreover, the molecular weight and composition of block copolymer have the an effect on pigment dispersion. In this study, adequate dispersants, block copolymers containing (2-dimethylamino)ethyl methacrylate as anchoring group and oligo(ethylene oxide)methyl ether methacrylate as a stabilizing group were designed and synthesized by atom transfer radical polymerization in order to prepare well-defined structure, molecular weight and composition.

Effects of Cognitive Heuristics on the Decisions of Actual Judges and Mock Jury Groups for Simulated Trial Issues (가상적인 재판 쟁점에서의 현역판사의 판단과 모의배심의 집단판단에 대한 인지적 방략의 효과)

  • Kwang B. Park;Sang Joon Kim;Mi Young Han
    • Korean Journal of Culture and Social Issue
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    • v.11 no.1
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    • pp.59-84
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    • 2005
  • Three studies were conducted to examine the degree to which three common heuristics, anchoring heuristic, framing effect and representative-ness heuristic, influence the decision-making precesses of actual judges and 5-persons mock juries. With scenarios regarding various issues that are commonly raised in actual criminal and civil trials, study 1 examined the 158 actual judges' decisions. In study 2, the decisions of 80 mock jury groups that consisted of college students were examined with similar scenarios. And individual decisions were examined in study 3 to compare with the group decisions in study 2. The decision processes of the actual judges and the mock jury groups alike were found to be influenced by "anchors". But the biases by the anchoring heuristic were more pronounced in the group decisions than in the decisions of the actual judges. With respect to framing effect, the actual judges were found to be resistant, while a small effect was found in the decisions of mock jury groups. Representative-ness biases weren't found in the decisions of both the actual judges and mock juries. The implications of the results for judicial systems were discussed.

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Behavioral Biases on Investment Decision: A Case Study in Indonesia

  • KARTINI, Kartini;NAHDA, Katiya
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.1231-1240
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    • 2021
  • A shift in perspective from standard finance to behavioral finance has taken place in the past two decades that explains how cognition and emotions are associated with financial decision making. This study aims to investigate the influence of various psychological factors on investment decision-making. The psychological factors that are investigated are differentiated into two aspects, cognitive and emotional aspects. From the cognitive aspect, we examine the influence of anchoring, representativeness, loss aversion, overconfidence, and optimism biases on investor decisions. Meanwhile, from the emotional aspect, the influence of herding behavior on investment decisions is analyzed. A quantitative approach is used based on a survey method and a snowball sampling that result in 165 questionnaires from individual investors in Yogyakarta. Further, we use the One-Sample t-test in testing all hypotheses. The research findings show that all of the variables, anchoring bias, representativeness bias, loss aversion bias, overconfidence bias, optimism bias, and herding behavior have a significant effect on investment decisions. This result emphasizes the influence of behavioral factors on investor's decisions. It contributes to the existing literature in understanding the dynamics of investor's behaviors and enhance the ability of investors in making more informed decision by reducing all potential biases.

Effect of nonionic surfactants on the electrorheology of emulsions

  • Ha, Jong-Wook;Moon, Jung-Hyuk;Yang, Seung-Man
    • Korea-Australia Rheology Journal
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    • v.11 no.3
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    • pp.241-246
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    • 1999
  • In this study, we consider the effect of nonionic surfactants on the rheological responses of emulsion systems under the action of a uniform do electric field. The model emulsions consist of a less conducting dispersed phase and a more conducting continuous phase. When the shear flow is weak, the positive viscosity effect is produced due to the formation of chain-like morphology. The nonionic surfactants used here generate two distinctively different effects. Specifically, first, the steric hindrance induced by the surfactant molecules renders the structure unstable, and thereby reduces the degree of positive viscosity effect. Secondly, the presence of surfactant molecules also prevents the rotation of the dispersed droplets by anchoring across the interface or by decreasing the size of dispersed phase. The second effect suppresses the negative viscosity effect.

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A Study on the Lubrication Characteristics of Liquid Crystals (액정의 윤활특성에 관한 연구)

  • 임윤철;민지홍
    • Tribology and Lubricants
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    • v.8 no.1
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    • pp.30-37
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    • 1992
  • The displacement and pressure field of liquid crystals are analyzed numerically and compared with classical Reynolds theory. A plane slider bearing is employed as a simple example considering elasticity, permeability and splay effect which are the inherent characteristics of layered liquid crystals. Due to the geometric constraint of thin wedge and the strong anchoring behavior of the liquid crystals dislocations are inevitable. A finite element method is used to solve five coupled nonlinear equations. The load characteristics based on the pressure distribution along the gap shows that the liquid crystals can carry large load compared to the conventional lubricants.