• Journal of Information Display
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• v.8 no.1
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• pp.6-9
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• 2007

Orientational alignment patterns have been proven to be that they are very useful for realizing diverse properties of liquid crystals. Here we produced the patterns combining interfered laser beams. A photo-isomerizable polymer including azo unit, which induces nematic liquid crystal alignment to the polarized laser light, was used as the alignment to layer. Double irradiations into two orthogonal directions brought the orientation patterns similar to the checkerboard. It indicates the possibility of bistability on those patterns.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.61.2-61
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• 2001

The purpose of the initial alignment of a SDINS is to get a coordinate transformation matrix from the body frame to the navigation frame. The initial alignment is one of the most important processes in the navigation system since its error has a large influence on the navigation solution. In this paper, a real-time initial alignment algorithm for the SDINS is developed using the Kalman filter. The steady state error analysis is performed for the developed Kalman filter technique and the gyrocompass loop method. The performance of the developed alignment method is compared with the gyrocompass loop method through the real-time alignment experiments.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.341-345
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• 2003

This study develops modeling processes for alignment optimization considering characteristics of intersections using genetic algorithms and GIS for road alignment optimization. Since existing highway alignment optimization models have neglected the characteristics of intersections, they have shown serious weaknesses for real applications. In this paper, intersection costs include earthwork, right-of-way, pavement, accident, delay and fuel consumption costs that are sensitive and dominating to alignments. Also, local optimization of intersections for saving good alignment alternatives is developed and embedded. A highway alignment is described by parametric representation in space and vector manipulation is used to find the coordinates of intersections and other interesting points. The developed intersection cost estimation model is sufficiently precise for estimating intersection costs and eventually enhancing the performance of highway alignment optimization models. Also, local optimization of intersections can be used for improving search flexibility, thus allowing more effective intersections. It also provides a basis for extending the alignment optimization from single highways to networks. The presented two artificial examples show that the total intersection costs are substantial and sensitive to highway alignments.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.8
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• pp.838-842
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• 2009

Vibrational analysis is presented for a visual alignment system of nano-imprint process in this study. For a nano-imprinting equipment, the visual alignment system is one of the essential parts in order to align the mold into the target panel. For the precision alignment, the vibration from inside and outside of the vision system should be avoided, and the elimination of the vibration should be considered in the design process of the visual alignment design. In this work, vibrational characteristics for the vision system frame is analyzed and topology optimization of a frame section area is carried out. With the results of the analysis, a new frame design are suggested. Design consideration for constructing a visual alignment system in view of optimal design is also discussed.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.7
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• pp.785-794
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• 2005

Modern ship hulls of large oil carriers and container carrers have become more flexible with scantling optimization and increase in ship length. On the other hand. as the demand for power has increased with the ship size. shaft diameters have become larger and stiffer. Consequently. the alignment of the propulsion system has become more sensitive to hull girder deflections. resulting in difficulties in analyzing the alignment and conducting the alignment procedure. Accordingly. the frequency of shaft alignment related bearing damages has increased significantly in recent years. The alignment related damages are mostly attributed to inadequate analyses. changes in the design of the vessel. shipyards' practices in conducting the alignment. and a lack of well defined analytical criteria. The hull deflections should be considered at the design stage to minimize the bearing damage caused by hull deflection. Hull deflections can be estimated by analytical approach and reverse calculation using the measured data. The hull girder deflection analysis using the reverse calculation will be introduced in this paper.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1388-1390
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• 1998

In this paper, we investigated the monodomain alignment of nematic liquid crystal(NLC) in the cell fabricated by transcription alignment method on polyimide(PI) surface with side chain. The LC alignment produced by the transcription alignment method is attributed to a memory effect of the NLC on PI surfaces. We observed that the pretilt angle of NLC is generated about $3.7^{\circ}$ with transcription alignment on PI surface. Also, we obtained the good electro-optical(EO) performance of twisted nematic(TN)-liquid crystal display(LCD) by transcription alignment method on PI surface.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.6
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• pp.64-70
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• 2003

A measurement of spacecraft alignment is an important process of spacecraft assembly, integration and test because it is necessary that a ground station controls the precise positions of on-orbit spacecraft by using the alignment data of attitude orbit control sensors(AOCS) on spacecraft. In addition, accuracy of spacecraft alignment requirement is about $0.1^{\circ}$~$0.7^{\circ}$. The spacecraft alignment is measured by autocollimation of theodolite. This paper describes the measurement principle and method of spacecraft alignment. The result shows that all of the AOCS on the spacecraft are aligned within the tolerance required through the alignment measurement.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.1083-1084
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• 2002

We prepared the blend alignment layers made from coumarin based photopolymer and polyimides for liquid crystal(LC) alignment using linearly polarized ultraviolet(UV) exposure. The alignment properties of LC were found to depend on the type of polyimide in the blend alignment layers. The degree of photereaction of polyimide was important factor for LC alignment direction on the blend alignment layers.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.11_12
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• pp.578-586
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• 2005

In this Paper we consider the problem of sequence alignment with quality scores. DNA sequences produced by a base-calling program (as part of sequencing) have quality scores which represent the confidence level for individual bases. However, previous sequence alignment algorithms do not consider such quality scores. To solve sequence alignment with quality scores, we propose a measure of an alignment of two sequences with orality scores. We show that an optimal alignment in this measure can be found by dynamic programming.

• International Journal of Aeronautical and Space Sciences
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• v.2 no.1
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• pp.44-54
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• 2001

This paper describes the antenna alignment method of the tracking antenna system for LEO satellite. The purpose of the antenna alignment is to reduce the angular error due to the structural alignment and the monopulse null point alignment error. The angular error of 3 axis tracking system is the key performance parameter that should be minimized to accurately track satellite movement. The angular error is analyzed via a simulation and boresight measurement. The simulation is done with formulas to be derived from vector concept for 3-axis movement. The formulas of the structural alignment are verified by comparing the formula result with the field measurement. Also, the angular error due to monopulse null shift is obtained via boresight measurement. Based on the analyzed and measured results, the antenna alignment was performed and was verified via tracking test of operating LEO satellite.