• Title/Summary/Keyword: inversion mode

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A Study of viewing angle characteristics of the film compensated TN mode

  • Park, Chi-Hyuck;Kim, Eui-Man;Lee, Jang-Ho;Park, Cheol-Woo;Lee, Kyung-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1462-1465
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    • 2009
  • Because of its weak points that narrow viewing angle and grayscale inversion, 'bare' twisted nematic (TN) LCD has some limits to use as a display device, though its great strong points that low cost, high yield, simple design, high transmittance and normally white. The 'WideView(WV)' film which introduced by Fuji co., has been good solution to extend the viewing angles of TN mode, therefore that film have been used generally for TN panels needed wide viewing angle. This paper introduce the research to find the parameters of the Wide view film and a TN panel which affect viewing angle characteristics and how to adjust those parameters.

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Neural Networks Based Adaptive Flight Controller Design and Handling Quality Evaluation for Tiltrotor Aircraft (신경회로망을 이용한 틸트로터 항공기의 적응 비행제어기 설계 및 비행성 평가)

  • Lee, Ki Young;Kim, Byoung Soo
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.21 no.3
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    • pp.1-8
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    • 2013
  • An application of adaptive flight controller is required for the non-linear and high uncertain system that configuration of tiltrotor aircraft is dramatically changed from rotary wing mode to fixed wing mode. In this paper, the applicable adaptive controller for the tiltrotor aircraft was designed using Neural Networks and DMI (Dynamic Model Inversion). The performance of the SCAS (Stability and Control Augmentation System) was simulated against manned military specification, using the fullscale model of 'Smart UAV(Unmanned Aerial Vehicle)' developed by Korea Aerospace Research Institute. And Neural Networks based adaptive controller was verified through its whole operating envelope using the established HQ (Handling Quality) criteria.

Viewing angle control of TN-LCD using optical compensation of two LC layers (두 액정 층의 광학적 보상을 이용한 비틀린 네마틱 액정 셀의 시야각 조절)

  • Choi, Min-Oh;Lim, Young-Jin;Jeong, Eun;Lee, Seung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.479-480
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    • 2006
  • We have studied the viewing angle control of a twist nematic liquid crystal display (TN-LCD). The TN-LCD exhibits a bad image quality along vertical direction, due to characteristics such as low contrast ratio and gray scale inversion. The proposed new TN-LCD has the function of switching between the wide viewing mode and narrow viewing angle mode using two tilted LC layers at both sides of a TN-cell. Tilt angles of the two LC layers, $14^{\circ}$ and $60^{\circ}$ were required in both wide viewing angle and narrow viewing angle modes, respectively.

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A Study on Parody Expressed in Modern Fashion (현대복식에 나타난 패러디에 관한 연구)

  • Yang, Lee-na;Kim, Moon-Suk
    • The Journal of Natural Sciences
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    • v.8 no.2
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    • pp.237-255
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    • 1996
  • Parody, which is the device of humorous Postmodernism artists, has been from the comic immitation with the popular and well-known object. It's expressive techniques are very various such as similarity, transformation, exaggeration, irony, parados, inversion etc. and also it can be used another techniques of designer's will and ability based. Parody's effect consists of satire, mockery, scorn, ridicule, unexpectedness, defamiliarize, playfulness, wit, respect, esteem, wonder and so on of the original. So parody has a critical distance from the original, whichis the object of immitation. Ultimately, the expression of parody can be as extensive as from an ironic and funny inversion still containing the respect for the original to a contemptuous mockery. Nowadays Parodists have a tendency to use parody actively in order to criticize the real world or to meet the past with ironic recontextualize. And parody include the specific characters of postmodern design. So parody is widely known as a effective forms of expression in now-a-days our environment surrounded with the postmodern esthetics, and it's request will be increased rapidly. As a part of art, parody is apt to use widely in Fashion too. And from a historical standpoint it is to reconstitute the past with a critical eye and finally to become a new technique to create the new Fashion style with an intention of extension of design area.

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Mid-span Spectral Inversion System Applied with Dispersion Management with Different RDPS Determinations for Half Transmission Link (반 전송 링크의 RDPS 결정 방식이 다른 분산 제어가 적용된 Mid-span Spectral Inversion 시스템)

  • Lee, Seong-Real
    • Journal of Advanced Navigation Technology
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    • v.26 no.5
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    • pp.331-337
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    • 2022
  • The length of optical fiber in dispersion-managed link combined with optical phase conjugation to compensate for signal distortion caused by chromatic dispersion and nonlinear Kerr effect is a major factor determining the compensation effectiveness. The dispersion-managed link consists of several fiber spans in which standard single mode fiber and dispersion compensating fiber are arranged. In this paper, the compensation effect in the link that changes residual dispersion per span only by adjusting the length of one type of optical fiber, which is different in the first half link and the second half link with respect to optical phase conjugator (OPC), has been investigated. It was confirmed that the best compensation for 960 Gb/s wavelength division multiplexed signal could be obtained in the dispersion-managed link, in which the cumulative dispersion profile is symmetric around the OPC, and the cumulative dispersion amount is all positive in the first half, and all the cumulative dispersion amount is distributed negatively in the second half.

The Study on the Parameters to Represent the Characteristics of the Observed Ground motions (국내 관측 지진파형을 이용한 지진파형 영향인자에 관한 연구)

  • 김준경
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.04a
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    • pp.44-48
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    • 2000
  • Several parameters to represent the characteristics of the observed at the domestic networks from several earthquakes occurred in the Korean Peninsula. Parameters to fit most the multiple Fourier amplitude spectra of the observed accelerations are estimated. This study adopts the stochastic ground motion model referred to the BLWN mode in which the energy is distributed randomly over the duration of the source and which has proven to be very effective in modeling a wide range of ground motion observations. The stochastic ground motion model employed here uses an omega-squared ({{{{ omega ^2 }}) Brune source model with a single corner frequency and a constant stress drop,. The {{{{ omega ^2 }} source model has become a seismological standard because of its simplicity an ability to predict spectral amplitudes and shapes over an extremely broad ranges of magnitudes distances and from the inversion show very unstable based on the fact of high values of mean/median. These results may imply that more observed data and more precise site classification including accurate preparation analysis of data such as more accurate scaling from counts to kine are needed for more stable are effective inversion of Fourier amplitude spectrum of the observed ground motions.

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Close-contact melting of ice in a horizontal cylinder (수평원관내 얼음의 접촉융해과정)

  • ;;Ro, Sung Tack
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.10
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    • pp.2595-2606
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    • 1995
  • Buoyancy-assisted melting of an unconstrained ice in an isothermally heated horizontal enclosure was numerically analyzed in a range of wall temperatures encompassing the density inversion point. The problem as posed here involves two physically distinct domains each of which has its own scales and respective heat transfer mode. These two domains join at the junction where the liquid squeezed out of the film region flushes into the lower melt pool. Both of these domains have been treated separately in the literature by a patching technique which invokes several, otherwise unnecessary, assumptions. The present study eliminates successfully such a superfluous procedure by treating the film and lower melt pool regions as a single domain. As a result of this efficient solution procedure, the interaction of the water stream ejected at the junction and the natural convection in the melt pool could be clarified for different wall temperatures. Though limited by two-dimensionality, the present results conformed indirectly the earlier reported transition of the flow pattern, as the wall temperature was increased over the density inversion point. The transient evolution of the melting surface, the time rate of change in melt volume fraction, the local and temporal variation of the heat transfer coefficients are analyzed and presented.

Effects of Annealing on Electrical Characteristics of Double-Gated Silicon Nanosheet Feedback Field-Effect Transistors (더블게이트 실리콘 나노시트 피드백 전계효과 트랜지스터의 전기적 특성에 미치는 열처리 효과)

  • Hyojoo Heo;Yunwoo Shin;Jaemin Son;Seungho Ryu;Kyoungah Cho;Sangsig Kim
    • Journal of IKEEE
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    • v.27 no.4
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    • pp.418-424
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    • 2023
  • In this study, we examined the effects of annealing on electrical characteristics of double-gated silicon nanosheet (SiNS) feedback field effect transistors (FBFETs). When bias stresses were applied for 1000 s, the double-gated SiNS FBFETs were more affected by positive bias stresses than negative bias stresses regardless of the channel mode owing to the increase of interface traps caused by electrons in the inversion layers. After annealing at 300 ℃ for 10 mins, the devices were completely recovered to their original properties, and the characteristics did not change anymore when bias stresses were applied again for 1000 s.

Free vibrations of precast modular steel-concrete composite railway track slabs

  • Kimani, Stephen Kimindiri;Kaewunruen, Sakdirat
    • Steel and Composite Structures
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    • v.24 no.1
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    • pp.113-128
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    • 2017
  • This paper highlights a study undertaken on the free vibration of a precast steel-concrete composite slab panel for track support. The steel-concrete composite slab track is an evolvement from the slab track, a form of ballastless track which is becoming increasingly attractive to asset owners as they seek to reduce lifecycle costs and deal with increasing rail traffic speeds. The slender nature of the slab panel due to its reduced depth of construction makes it susceptible to vibration problems. The aim of the study is driven by the need to address the limited research available to date on the dynamic behaviour of steel-concrete composite slab panels for track support. Free vibration analysis of the track slab has been carried out using ABAQUS. Both eigenfrequencies and eigenmodes have been extracted using the Lanczos method. The fundamental natural frequencies of the slab panel have been identified together with corresponding mode shapes. To investigate the sensitivity of the natural frequencies and mode shapes, parametric studies have been established, considering concrete strength and mass and steel's modulus of elasticity. This study is the world first to observe crossover phenomena that result in the inversion of the natural orders without interaction. It also reveals that replacement of the steel with aluminium or carbon fibre sheeting can only marginally reduce the natural frequencies of the slab panel.

Damped frequencies of precast modular steel-concrete composite railway track slabs

  • Kaewunruen, Sakdirat;Kimani, Stephen Kimindiri
    • Steel and Composite Structures
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    • v.25 no.4
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    • pp.427-442
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    • 2017
  • This paper presents unprecedented damped oscillation behaviours of a precast steel-concrete composite slab panel for track support. The steel-concrete composite slab track is an innovative slab track, a form of ballastless track which is becoming increasingly attractive to asset owners as they seek to reduce lifecycle costs and deal with increasing rail traffic speeds. The slender nature of the slab panel due to its reduced depth of construction makes it susceptible to vibration problems. The aim of the study is driven by the need to address the limited research available to date on the dynamic behaviour of steel-concrete composite slab panels for track support. Free vibration analysis of the track slab has been carried out using ABAQUS. Both undamped and damped eigenfrequencies and eigenmodes have been extracted using the Lancsoz method. The fundamental natural frequencies of the slab panel have been identified together with corresponding mode shapes. To investigate the sensitivity of the natural frequencies and mode shapes, parametric studies have been established, considering concrete strength and mass and steel's modulus of elasticity. This study is the world first to observe crossover phenomena that result in the inversion of the natural orders without interaction. It also reveals that replacement of the steel with aluminium or carbon fibre sheeting can only marginally reduce the natural frequencies of the slab panel.