• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.1096-1101
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• 1992

In order tominimize fixing error of workpieces, circle, prismatic, sphere, cylindrical and sculptures types. Modification Rule by Indexing Table and Modification Rule by NC Program are developed for machining centers by using touch trigger probes. The Modification Rule by Indexing Table meas the alignment of workpiece to NC program through degree of freedoms of indexing table. The Modification Rule by NC Program is the alognment of NC program to workpiece ste-tp condition via the generation of NC progarm. A postprocessing module is alos developed for generating NC-part program(User Macro) to compensate for machining errors in end milling and boring processes. Developed method are verified by experiments.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.1-4
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• 2000

We have developed a high performance vertical alignment TFT-LCD, that shows a high light transmittance, and wide viewing angle characteristics with an unusually high contrast ratio. In order to optimize the electro-optical properties we have studied the effect of cell parameters, multi-domain structure and retardation film compensation. With the optimized cell parameters and process conditions, we have achieved a 24" wide UXGA TFT-LCD monitor (16:10 aspect ratio 1920X1200) showing a contrast ratio over 500:1, panel transmittance near 4.5%, response time near 27 ms, and viewing angle higher than 80 degree in all directions.

• Proceedings of the Safety Management and Science Conference
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• 2008.11a
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• pp.561-567
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• 2008

The objectives of this study is to: (1) develop how applications for driving simulator of national highway safety designs when those are appeared; (2) examine the degree to which those geometric designs of the horizontal and vertical profile; and (3) search positive safety and passive highway safety design of the point at which highway alignment factors initiate driving safety to facility or highway design.

• Journal of The Korean Astronomical Society
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• v.40 no.4
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• pp.113-118
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• 2007

Recently far infra-red (FIR) polarization of the $850{\mu}m$ continuum emission from T Tauri disks has been detected. The observed degree of polarization is around 3 %. Since thermal emission from dust grains dominates the spectral energy distribution at the FIR regime, dust grains might be the cause of the polarization. We explore alignment of dust grains by radiative torque in T Tauri disks and provide predictions for polarized emission for disks viewed at different wavelengths and viewing angles. In the presence of magnetic field, these aligned grains produce polarized emission in infrared wavelengths. When we take a Mathis-Rumpl-Nordsieck-type distribution with maximum grain size of $500-1000{\mu}m$, the degree of polarization is around 2-3 % level at wavelengths larger than ${\sim}100{\mu}m$. Our study indicates that multifrequency infrared polarimetric studies of protostellar disks can provide good insights into the details of their magnetic structure.

• Journal of Korean Society of Transportation
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• v.23 no.3 s.81
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• pp.73-84
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• 2005

Highway design criteria are considering roadway safety and smooth driving maneuver. However, a certain highway alignment within design criteria often leads drivers to undesirable situation due to the differences between the original intention of design criteria and the unintended result of drivers' cognition. The differences between them often result in traffic accidents. In order to reduce accident process, highway safety facilities are installed on those roadway sections. However, the relationship between highway environments and human factors has not been deeply studied in Korea. In this study. vertical roadway sections are constructed with 3-D graphical tools. This vertical roadway sections are simulated on a driving simulator in order to identify the differences of drivers' cognition on different roadway environments. Based upon the collected data from the driving simulator, canonical correlation analysis and canonical discriminant analysis of quantification theory II have been performed in order to figure out impacting factors on the degree of roadway safety. Also, based upon quantification theory I. the relationship between roadway safety facilities and the degree of safety has been analyzed.

• Medical Lasers
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• v.9 no.1
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• pp.44-50
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• 2020

Background and Objectives To evaluate the rotational stability of AcrySof toric intraocular lenses (IOL) by considering lapse of postoperative time and influence of capsulorhexis contraction. Materials and Methods A prospective, masked, single center study was conducted on 19 patients who had undergone microcoaxial cataract surgery and AcrySof toric IOL implantation. Slit-lamp retroillumination photographs of anterior segments were obtained from all patients after 1 week, 1 month and 3 months post-surgery. The degree of alteration of the postoperative IOL axis alignment and the amount of anterior capsular shrinkage were analyzed using Adobe Photoshop software. Results The mean degree of toric IOL axis misalignment was 2.18 (±20.2) degrees at 3 months follow-up. Quadrant analysis of the capsulorhexis aperture area at 1 week and 1 month post-operative, showed counterclockwise IOL rotation when the capsule contraction was dominant in the haptic part as well as clockwise rotation when dominant in the non-haptic part (p = 0.015). Conclusion The direction and degree of AcrySof toric IOL rotation differed throughout the follow-up period. Since most misalignments were found on the first post-operative day, physicians should try to minimize peri-operative risk factors that influence IOL rotation. There was also a correlation between the part of anterior capsule contraction and the direction of IOL rotation.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.3
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• pp.285-291
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• 2017

Micro-needles are used as transferring devices for sampling of tiny constitute substances from biological bodies. Typically, nickel is used as a coating to improve the rigidity of micro-needles. This study introduces the methodology to manufacture a WC needle with very high hardness and toughness. Micro-EDM technology was used to manufacture micro-needles with holes $130{\mu}m$ in diameter and $2300{\mu}m$ in length. A micro-needle was aligned to the micro-EDM electrode using a custom two degree-of-freedom alignment system. A three-step manufacturing technique was developed to drill a micro-hole using a WC electrode. In the first process, an electrode $105{\mu}m$ in diameter was used to make a hole. Electrodes of 90 and $105{\mu}m$ diameters were used in the second and third process, respectively. Consequently, a WC micro-needle with an inner hole of $135{\mu}m$ diameter, length of $2300{\mu}m$, and outer diameter of $300{\mu}m$ was developed.

• Carbon letters
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• v.15 no.2
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• pp.142-145
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• 2014

Isotropic synthetic graphite scrap and phenolic resin were mixed, and the mixed powder was formed at 300 MPa to produce a green body. New bulk graphite was produced by carbonizing the green body at $700^{\circ}C$, and the bulk graphite thus produced was impregnated with resin and re-carbonized at $700^{\circ}C$. The bulk density of the bulk graphite was $1.29g/cm^3$, and the porosity of the open pores was 29.8%. After one impregnation, the density increased to $1.44g/cm^3$ while the porosity decreased to 25.2%. Differences in the pore distribution before and after impregnation were easily confirmed by observing the microstructure. In addition, by using an X-ray diffractometer, the degrees-of-alignment (Da) were obtained for one side perpendicular to the direction of compression molding of the bulk graphite (the "top-face"), and one side parallel to the direction of compression molding (the "side-face"). The anisotropy ratio calculated from the Da-values obtained was 1.13, which indicates comparatively good isotropy.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.3
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• pp.479-486
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• 2012

This paper presents a high-speed automatic micro-alignment system that is a part of an inspection machine for small-sized molded lenses of mobile phones, palm-top computers, and so on. This work was motivated by the shortcomings of existing highest-grade commercial machine. A simple tip/tilt/Z parallel mechanism is designed based on kinematic couplings, which is a 3-degree-of-freedom (3-DOF) moderate-cost alignment stage. It is used to automatically adjust the posture of each lens on the tray, which is impossible by the conventional instrument. Amplified piezoelectric actuators are used to ensure the accuracy and dynamic response. Forward kinematic analysis and simulation show that the parasitic motion is small enough compared to the actuator stroke. From the workspace analysis of the moving platform, it is clear that the output motion range satisfies the design requirements.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.2
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• pp.209-218
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• 1995

It is important role that railway speed up plays in realizing an affluent society in future. Curved lines zone have crucial effects on the speed of train travel, at the curved lines zone, it requires to set cant and slack for safety running of train and comfortable ride of passengers, a compromise is therefore to accept a certain degree of cantdeflciencyforthevarioustrain. In this study, it was presented that effective maintenance method according to the investigation of cant value in radius of curvature and analysis safety running of train, calculation of lateral acceleration as cant deficiency, and we obtain the effect of speed up appling route alignment improvement parameter in curved lines zone.