• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2005.05a
• /
• pp.203-208
• /
• 2005

In recent years, as the demands of VBNS and VDSL increase, the development of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, and WDM elements increases. The alignment and the attachment technology are very important in the fabrication of optical elements. In this paper, the optical alignment characteristics of multi-axis ultra precision stage were studied. The alignment algorithms were studied for applying to the ultra precision multi-axis stage. The alignment algorithm is comprised of field search and peak search algorithms. The contour of optical power signals can be obtained by field search and the precise coordinate can be found out by peak search. Two kinds of alignments, such as 1 ch. input vs. 1 ch. output optical stack, and 1 ch. input vs. 8 ch. output PLC stacks were performed for investigating the alignment characteristics.

• Proceedings of the Optical Society of Korea Conference
• /
• 1997.08a
• /
• pp.65-65
• /
• 1997

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2004.04a
• /
• pp.219-224
• /
• 2004

In recent years, as the demands of VBNS(Very high speed Backbone Network Service) and VDSL(Very high-data rate Digital Subscriber Line) increase, the development of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, WDM elements increase. The alignment and the attachment technology are very important to fabricate the optical elements for communication. In this paper, the mechanism of rotational stage, the contact sensing unit, and integrated control circuit for the optical alignment system are studied.

• Journal of Information Display
• /
• v.7 no.2
• /
• pp.12-15
• /
• 2006

We propose a patterning method of liquid crystal (LC) alignment layer for producing multi-domain LC structures. By controlling thermal conditions during micro-contact printing procedures and facilitating wetting properties of patterning materials, patterned LC orientation can be easily obtained on a bare ITO surface or other polymer films. The newly proposed patterning method is expected to be a very useful tool for fabricating multi-domain LC structures to enhance or design electro-optic properties of LC-based devices.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2003.10a
• /
• pp.143-148
• /
• 2003

In recent years, as the optical Communication systems are developed, the demands of essential parts such as splitter, coupler, WDM, and AWG filter are grow rapidly. The fabrication process for them is not, however, automatic. On that reason, the automation is needed for the grow of productivity. The optical alignment and attach ment is the core process in fabrication. In this paper, the 6-axis rotary stage for multi-channel optical alignment system is developed and the dynamic characteristic of this system is studied.

• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.12
• /
• pp.105-114
• /
• 2003

In this study, a dicing machine with vision system was built and an algorithm for automatic alignment was developed for dual camera system. The system had a macro and a micro inspection tool. The algorithm was formulated from geometric relations. When a wafer was put on the cutting stage within certain range, it was inspected by vision system and compared with a standard pattern. The difference between the patterns was analyzed and evaluated. Then, the stage was moved by x, y, $\theta$ axes to compensate these differences. The amount of compensation was calculated from the result of the vision inspection through the automatic alignment algorithm. The stage was moved to the compensated position and was inspected by vision for checking its result again. Accuracy and validity of the algorithm was discussed from these data.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.18 no.1
• /
• pp.83-89
• /
• 2009

In most multi-stage forging processes, the die spotting process or alignment of punch and die depends on the manual operation. It results a very tedious and inefficient procedure, thus the proper measurement system is needed to improve productivity and accuracy. This paper proposes a measurement system for alignment of die and punch which has a cylindrical holder, and describes the system concepts using 3 eddy-current displacement transducers and precise measurement jig. In order to apply this measurement system to real situations, the measuring procedures and system calibration method, etc. are proposed. Finally, the accuracy and productivity of this measurement system are investigated in this paper.

• Korean Journal of Microbiology
• /
• v.35 no.2
• /
• pp.115-120
• /
• 1999

Multiple Sequence Alignment of DNA and protem sequences is a imnport'mt tool in the study of molecular evolution, gene regulation. and prolein suucture-function relationships. Progressive pairwise alignment method generates multiple sequence alignment fast but not necessarily with optimal costs. Dynamic programming generates multiple sequence alig~~menl with optimal costs in most cases but long execution time. In this paper. we suggest genetlc algorithm lo improve the multiple sequence alignment generated from the cnlent methods, describe the design of the genetic algorithm, and compare the multiple sequence alignments from 0111 method and current methods.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.43 no.5
• /
• pp.651-657
• /
• 2023

Railroad alignment improvements and operating speed increase occupy considerable portion in recent railroad market. Developing countries have limitations to construction of new high speed railroads due to the burden of budgets and the lack of demands, and the projects of operating speed increase arepracticallyrecommended. Thisstudy developed the methodologyto provide the railroad alignment design alternatives and the costs by upgrading the "Intelligent Railroad Alignment Design Program (ei-Rail)" which has been used to obtain the alignment plans and construction costs for railroad construction projects. The program provides the cost for alignment improvement, design drafts and the effects of operating speed increase with the input of target improvement speed and the prevailing railroad alignment on the numerical map. It is then expected for the ei-Rail program to be used for the supporting tool for the railroad alignment improvement projects.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.10a
• /
• pp.387-388
• /
• 2006