• Title/Summary/Keyword: alignment configurations

Search Result 16, Processing Time 0.022 seconds

Liquid crystal alignment on patterned-alignment films

  • Lias, Jais Bin;Oo, Thet Naing;Yazawa, Tomohiro;Kimura, Munehiro;Akahane, Tadashi
    • Journal of Information Display
    • /
    • v.12 no.2
    • /
    • pp.101-107
    • /
    • 2011
  • To come up with a bistable liquid crystal (LC) device using unpolarized UV light, single-step laser patterning on a photoalignment layer using a photomask was proposed to achieve an equilibrium configuration of LC molecules in contact with a periodically patterned substrate. The patterns were formed by stripes of alternating random planar and homeotropic anchoring on a submicrometer scale in the order of $0.5{\mu}m$. Two possible configurations of bistable LC cells that can be obtained by combining a micropatterned surface formed with alternating random-planar- and homeotropic-alignment with planar- or homeotropic-alignment surfaces were proposed. The alignment properties of the two proposed models were investigated, along with the microscopic switching behavior of micropatterned nematic LC cells.

Seismic pounding effects on adjacent buildings in series with different alignment configurations

  • Abdel Raheem, Shehata E.;Fooly, Mohamed Y.M.;Abdel Shafy, Aly G.A.;Abbas, Yousef A.;Omar, Mohamed;Abdel Latif, Mohamed M.S.;Mahmoud, Sayed
    • Steel and Composite Structures
    • /
    • v.28 no.3
    • /
    • pp.289-308
    • /
    • 2018
  • Numerous urban seismic vulnerability studies have recognized pounding as one of the main risks due to the restricted separation distance between neighboring structures. The pounding effects on the adjacent buildings could extend from slight non-structural to serious structural damage that could even head to a total collapse of buildings. Therefore, an assessment of the seismic pounding hazard to the adjacent buildings is superficial in future building code calibrations. Thus, this study targets are to draw useful recommendations and set up guidelines for potential pounding damage evaluation for code calibration through a numerical simulation approach for the evaluation of the pounding risks on adjacent buildings. A numerical simulation is formulated to estimate the seismic pounding effects on the seismic response demands of adjacent buildings for different design parameters that include: number of stories, separation distances; alignment configurations, and then compared with nominal model without pounding. Based on the obtained results, it has been concluded that the severity of the pounding effects depends on the dynamic characteristics of the adjacent buildings and the input excitation characteristics, and whether the building is exposed to one or two-sided impacts. Seismic pounding among adjacent buildings produces greater acceleration and shear force response demands at different story levels compared to the no pounding case response demands.

Transflective IPS LCD with Multi-Domain Structures

  • Park, Kyoung-Ho;Ko, Young-Jo;Kim, Jung-Hyoung;Kim, Jae-Chang;Yoon, Tae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.895-898
    • /
    • 2004
  • We propose configurations for a transflective in-plane switching (IPS) cell using muti-domain structures. Usually, the cell configurations for a transflective liquid crystal(LC) cell have a complicated structure, because retardation change of transmissive part and reflective part are not same. The transflective LC cell should have two configurations for each part, such as a multi-cell gap structure. With the ion-beam alignment and the horizontal switching LC cell, a simple structure for a transflective LC cell is proposed. The configuration only adopts one cell gap structure, which may help the enhancement of a yield. Their original optical properties in conventional transmissive and reflective type IPS liquid crystal dispaly(LCD) are kept, it shows the wide-viewing angle and the good wavelength dispersion characteristics.

  • PDF

Haplotype Phylogeny of a 200kb Region in the Human Chromosome X Terminal Band (q28)

  • Kim, Sang-Soo
    • Genomics & Informatics
    • /
    • v.6 no.3
    • /
    • pp.130-135
    • /
    • 2008
  • The haplotypes of a 200 kb region in the human chromosome X terminal band (q28) were analyzed using the International HapMap Project Phasell data, which had been collected for three analysis panels (YRI, CEU, and CHB+JPT). When multiple linkage disequilibrium blocks were encountered for a panel, the neighboring haplotypes that had crossover rate of 5% or more in the panel were combined to generate 'haploid' configurations. This resulted in 8, 7, and 5 'haploid' configurations for the panels of YRI, CEU, and CHB+JPT, respectively. The multiple sequence alignment of these 'haploids' was used for the calculation of allele-sharing distances and the subsequent principal coordinate analysis. Two 'haploids' in CEU and CHB+JPT were hypothesized as 'parental' in light of the observations that the successive recombinants of these haploids can model two other haploids in CEU and CHB+JPT, and that their configurations were consistent with those in YRI. This study demonstrates the utility of haplotype phylogeny in understanding population evolution.

Seismic pounding effects on the adjacent symmetric buildings with eccentric alignment

  • Abdel Raheem, Shehata E.;Fooly, Mohamed Y.M.;Omar, Mohamed;Abdel Zaher, Ahmed K.
    • Earthquakes and Structures
    • /
    • v.16 no.6
    • /
    • pp.715-726
    • /
    • 2019
  • Several municipal seismic vulnerability investigations have been identified pounding of adjacent structures as one of the main hazards due to the constrained separation distance between adjacent buildings. Consequently, an assessment of the seismic pounding risk of buildings is superficial in future adjustment of design code provisions for buildings. The seismic lateral oscillation of adjacent buildings with eccentric alignment is partly restrained, and therefore a torsional response demand is induced in the building under earthquake excitation due to eccentric pounding. In this paper, the influence of the eccentric seismic pounding on the design demands for adjacent symmetric buildings with eccentric alignment is presented. A mathematical simulation is formulated to evaluate the eccentric pounding effects on the seismic design demands of adjacent buildings, where the seismic response analysis of adjacent buildings in series during collisions is investigated for various design parameters that include number of stories; in-plan alignment configurations, and then compared with that for no-pounding case. According to the herein outcomes, the effects of seismic pounding severity is mainly depending on characteristics of vibrations of the adjacent buildings and on the characteristics of input ground motions as well. The position of the building wherever exterior or interior alignment also, influences the seismic pounding severity as the effect of exposed direction from one or two sides. The response of acceleration and the shear force demands appear to be greater in case of adjacent buildings as seismic pounding at different levels of stories, than that in case of no-pounding buildings. The results confirm that torsional oscillations due to eccentric pounding play a significant role in the overall pounding-involved response of symmetric buildings under earthquake excitation due to horizontal eccentric alignment.

A New Method for Measuring Azimuthal Anchoring Energy of Rubbed and UV-Exposed Polyimide Alignment Layers

  • Park, H.J.;Lee, W.K.;Kim, D.G.;Shin, D.C.;Woo, J.W.;Shin, H.H.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08b
    • /
    • pp.1619-1621
    • /
    • 2007
  • Novel optical measurement systems and improved cell configurations for measuring of azimuthal anchoring energies were developed. The difference between the mechanical rubbing direction and the optical easy axis that caused errors in the previous azimuthal anchoring energy measurement was compensated. In addition, the measurement accuracy of the twist angle and therefore the azimuthal anchoring energy was greatly enhanced. As a result, we were able to obtain valid azimuthal anchoring energy values for different alignment layers.

  • PDF

Two-position alignment of strapdown inertia navigation system

  • Lee, Jang-Gyu;Kim, Jin-Won;Park, Heong-won;Park, Chan-Gook
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1994.10a
    • /
    • pp.665-671
    • /
    • 1994
  • Some extended results in the study of two-position alignment for strapdown inertial navigation system are presented. In [1], an observability analysis for two-position alignment was done by analytic rank test of the stripped observability matrix and numerical calculation of the error covariance propagation using ten-state error model. In this paper, it is done by an analytic approach which utilizes the nonsingular condition of the determinant of simplified stripped observability matrix and by numerical calculation of the error covariance propagation accomplished in more cases than [1], and the twelve-state error model including vertical channel is used instead of ten-state error model. In addition, it is confirmed that this approach more clearly produces the same result as shown in the original work in terms of complete observability and there exist some better two-position configurations than [1] using the twelve-state error model.

  • PDF

Degrees of Freedom of Multi-Cell MIMO Interference Broadcast Channels With Distributed Base Stations

  • Huang, Hongbing;Liu, Junyi;Zhang, Yi;Cai, Qing;Zhang, Bowei;Jiang, Fengwen
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.13 no.2
    • /
    • pp.635-656
    • /
    • 2019
  • In this paper, we investigate the degrees of freedom (DoF) of a multi-cell multi-user multiple-input multiple-output (MIMO) interference broadcast channel (IBC) with non-cooperation distributed base stations (BS), where each BS serves users of its corresponding cell. When all BSs simultaneously transmit their own signals over the same frequency band in the MIMO IBC, the edge users in each cell will suffer the inter-cell interference (ICI) and inter-user interference (IUI) signals. In order to eliminate the ICI and IUI signals, a distributed space time interference alignment (DSTIA) approach is proposed where each BS has only limited access to distributed moderately-delay channel state information at the transmitter (CSIT). It is shown that the DSTIA scheme can obtain the appreciate DoF gains. In addition, the DoF upper bound is asymptotically achievable as the number of antenna at each BS increases. It is shown that the DSTIA method can get DoF gains over other interference alignment schemes with delayed CSIT in literature. Moreover, the DSTIA method can attain higher DoFs than the IA schemes with global CSIT for certain antenna configurations.

Effect of a through-building gap on wind-induced loading and dynamic responses of a tall building

  • To, Alex P.;Lam, K.M.;Wong, S.Y.;Xie, Z.N.
    • Wind and Structures
    • /
    • v.15 no.6
    • /
    • pp.531-553
    • /
    • 2012
  • Many tall buildings possess through-building gaps at middle levels of the building elevation. Some of these floors are used as sky gardens, or refuge floors, through which wind can flow with limited blockage. It has been reported in the literature that through-building gaps can be effective in reducing across-wind excitation of tall buildings. This paper systematically examines the effectiveness of two configurations of a through-building gap, at the mid-height of a tall building, in reducing the wind-induced dynamic responses of the building. The two configurations differ in the pattern of through-building opening on the gap floor, one with opening through the central portion of the floor and the other with opening on the perimeter of the floor around a central core. Wind forces and moments on the building models were measured with a high-frequency force balance from which dynamic building responses were computed. The results show that both configurations of a through-building gap are effective in reducing the across-wind excitation with the one with opening around the perimeter of the floor being significantly more effective. Wind pressures were measured on the building faces with electronic pressure scanners to help understand the generation of wind excitation loading. The data suggest that the through-building gap reduces the fluctuating across-wind forces through a disturbance of the coherence and phase-alignment of vortex excitation.

Feasibility of Interference Alignment for Reverse Duplex in MIMO Cellular Networks with One-side Base Cooperation (다중 안테나를 사용하는 단방향 기지국 협력 역 듀플렉스 셀룰러 네트워크의 간섭 정렬 타당성)

  • Kim, Kiyeon;Jeon, Sang-Woon;Yang, Janghoon;Kim, Dong Ku
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.40 no.2
    • /
    • pp.273-284
    • /
    • 2015
  • The feasibility conditions of interference alignment (IA) are analyzed for reverse duplex systems, in which one cell operates as downlink (DL) while the other cell operates as uplink (UL) assuming one-sid base station (BS) cooperation. Under general multiple-input and multiple-output (MIMO) antenna configurations, a necessary condition and a sufficient condition for one-shot linear IA are established, i.e., linear IA without symbol or time extension. In several example networks, optimal sum degrees of freedom (DoF) is characterized by the derived necessary condition and sufficient condition. For some special class of networks, a sufficient condition is established in a more compact expression, which also yields the necessary and sufficient condition. Simulation results demonstrate that the proposed IA does not only achieve larger DoF but also significantly improves the sum rate in the practical signal-to-noise ratio (SNR) regime.