• 한국정밀공학회지
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• 제18권2호
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• pp.90-95
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• 2001

f-$\theta$len is one of the important parts in Laser Scanning Unit because it affects on the optical performance of Laser Scanning Unit dominantly. It is necessary to find out the relationship between the surface profile error of f-$\theta$lens and the beam profile focusing on the Organic Photo Conductive drum in order to analysis the beam profile problems such as appearance of side lobe and expansion of center lobe. In this research, a simulation process which relates the surface profile characteristics to the beam profile has been developed by CODE V. The simulated beam profile also have been compared with the measurement results.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.164-167
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• 2003

Profile ring rolling process is simulated by using the general purpose commercial finite element analysis software MSC.Superform Because the deforming region is restricted to the vicinity of the roll gap, only a ring segment spanning the roll gap is analysed in order to save computation time and cost. A profile ring with an external round groove is chosen as an example to be analysed. The rolls with and without groove were analysed to compare the amount of side spread. It is found that the grooves in the rolls reduce the amount of side spread.

• International Journal of Automotive Technology
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• 제5권1호
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• pp.23-31
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• 2004

Secondary movements of piston in the bore clearance are closely related to the side impact to the engine block as well as many tribological problems. Some of the major parameters that influence these kinds of movements are piston profile shapes (barrel and flat), piston pin offsets and the magnitudes of bore clearances. In our study, computational investigations are performed about the piston movements in the bore clearance by changing the skirt profiles and piston offsets. In this work, it is found that curved profile and larger offset magnitude to thrust side provide better performance that has low side impact during the engine cycle.

• KSTLE International Journal
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• 제3권2호
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• pp.84-89
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• 2002

Clearance movements of engine piston are very related to the piston impact to the engine block as well as many tribological problems. Some of the major parameters that influence these kinds of performances are piston profiles, piston offsets and clearance magnitudes. In our study, computational investigation is performed about the piston movements in the clearance between piston and cylinder liner by changing the skirt profiles and piston offsets. Our results show that curved profile and more offset magnitude to thrust side have better performance that has low side impact during the engine cycle.

• 소성∙가공
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• 제12권7호
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• pp.631-639
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• 2003

Ring rolling process is simulated by using the general-purpose commercial finite element analysis software, MSC.Superform. Because the deforming region is restricted to the vicinity of the roll gap, only a ring segment spanning the roll gap is analyzed in order to save computation time and cost. First, a plain ring rolling of rectangular cross-section is simulated. Comparisons between computation and experiment show good agreement in the cross-sectional configuration of the deformed ring. Then, a profile ring with an external round groove is analyzed. The rolls with and without groove have been analyzed to compare the amount of side spread. It is found that the grooves in the rolls are effective in reducing the amount of side spread.

• 산업공학
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• 제11권2호
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• pp.65-78
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• 1998

The letters of the automobile tire are usually engraved on the side-wall. The shape of the side-wall is a sculptured surface generated by the rotational sweeping of a profile curve. The letters laid on the side-wall are usually designed by a 2-dimensional CAD. It is impossible to machine the letters on the surface accurately by 3-axis NC machining, because the axis of cutter should be tilted to align with the normal vector of the surface. In this case. the degree of freedom for the machine is at least four. This paper describes an idea for tool path generation of a 4-axis machine by using the 2-dimensional CAD data of the letters and the surface of the side-wall. This study includes the following procedures; (1) measuring the profile of the side-wall surface and curve-fitting of the measured points. (2) the 'non-parallel projection' of the letters on the side-wall, and (3) an inverse kinematics of the 4-axis lettering machine. Procedures in this paper are programmed in C-language on Windows95 environment. With a PC based CNC controller and a 4-axis lettering machine. these are tested sucessfully for the practical use.

• 한국결정성장학회지
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• 제28권5호
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• pp.179-184
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• 2018

고효율 태양전지용 단결정 실리콘 웨이퍼는 쵸크랄스키 성장법으로 석영도가니 속의 실리콘 액체에서 단결정 잉곳을 성장시켜 제조된다. 석영도가니 성분 중의 하나는 산소는 실리콘 잉곳으로 유입되고, 태양전지의 전력변환 효율 저하 문제를 발생시킨다. 이러한 산소 유입을 줄이는 다양한 방법 중 하나는 히터의 모양과 구조를 변경하는 방법이 있다. 그러나 히터 구조 변경 시 단결정 실리콘 잉곳 바디 성장에 필요한 온도 분포경향에 큰 변화를 일으킨다. 따라서 본 연구에서는 쵸크랄스키 실리콘 성장에서 다양한 히터의 구조와, 히터와 석영도가니의 상대적 위치가 단결정 실리콘 잉곳 Body 성장 시의 ATC 온도와 Power 분포경향에 미치는 영향에 대하여 연구하였다. 삼중점과 히터 중심과의 위치가 가장 먼 SSH-Low가 가장 높은 ATC 온도 분포경향을 보여주었다. 또한 길이가 짧은 Short Side Heater(SSH-Up, SSH-Low)보다는 실리콘 액체를 담고 있는 석영도가니 측면의 많은 영역을 커버할 수 있는 일반 Side Heater(SH)가 가장 Power 소모 측면에서 유리하였다. 특히 본 연구 결과를 통해 고효율 태양전지용 단결정 실리콘 잉곳 성장 시 필요한 효율적인 ATC 온도를 예측할 수 있음을 확인하였다.

• Steel and Composite Structures
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• 제7권1호
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• pp.71-85
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• 2007

This study suggests modular composite profile beams, where the prefab concept is applied to existing composite profile beams. The prefab concept produces a beam of desired size having two types of profile: side module and bottom module. Module section will improve construction efforts because it offers several benefits : reduction of deflections due to creep and shrinkage, which might be found in existing composite profile beams; increase in span/depth ratio; and free prefabrication of any required beams. Based on the established analysis theory of composite profile beams, an analysis theory of modular composite profile beams was suggested, and analysis values were compared with experimental ones. The behavior of individual modules with increase of load was measured with a strain gauge, and the shear connection ratio between modules was analyzed by using the measured values. As a result of experiment, it was found that theoretical flexural strength on condition of full connection was 57%-80% by connection of modules for each specimen, and it is expected that flexural strength will approximate the theoretical levels through further module improvement.

• 융합신호처리학회 학술대회논문집
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• 한국신호처리시스템학회 2000년도 하계종합학술대회논문집
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• pp.333-336
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• 2000

In this paper, a profile management system consisting of global and local range finders is presented for the automat ion of material pile handling. A global range finder detects range data of the front part of the piles of material and a profile map is obtained from a 3D profile detection algorithm. A local range finder attached on the side of the arm of the reclaimer detects range data with the handling function dynamically, and a local profile patch is acquired from the range data A yard profile map manager constructs a map by using the 3D profile of the global range finder and revises the map by replacing it with the local profile patch obtained Iron the local range finder. The developed vision system was applied to a simulator and the results of test show that it is appropriate to use for automating the material handling.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.427-428
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• 2002

Clearance movements of engine piston are regarded very important because they cause impact vibrations as well as many tribological problems. Some of the major parameters that influence these kinds of performances are piston profiles, piston offsets and clearance magnitudes. In our study. computational investigation is performed about the piston movements in the clearance between piston and cylinder liner by changing the skirt profiles and piston offsets. Our results show that curved profile and more offset to thrust side have better performance with low side impact during the engine cycle.