• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.810-813
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• 2000

Burr makes trobles on manufacturing process due to deburring cost, quality of products and productivity. This paper described the results of experimental study on the influence of the cutting parameters on the formation of exit burrs in face milling. The cutting parameters were investigated changing exit angle, rake nagle , lead angle in tool geometry as well as feed per tooth. Also we carried out experimets on several materials. Using the result of experimental study, burr types are classified according to appearance and formation mechanism in exit burr and we are considered the burr formation in each type of burr.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.788-793
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• 1997

The surface,generated by end milling operation, is deteriorated by tool runout,vibration,friction,tool deflection, etc. In many source,deflection of tool affects to surfave accuracy. To develop a surface accracy model,method for the prediction of the topography of machined surfaces has been developed based on models of machine tool kinematics and cutting tool geometry. This model accounts for not only the ideal geometrical surface, but also the deflection of tool resulted in cutting force. For the more accurate prediction of cutting force,flexible end mill model is used to simulate cutting process. Compute simu;ation have shown the feasibility of the surface generation system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.19-22
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• 1997

The objective of this research is to use an analytical and experimental approach to develop optimal tool geometry for high speed machining. The tool geometry parameters and cutting process have complex relationships. Until now, numerous cutting tests were needed to acquire optimal design of endmill for the purpose of high speed machining, dut to the insufficient knowledge about process in high speed machining. In order to improve the cutting ability of endmill, a model for optimal cutter shape was developed to minimize resultant cutting force by combing cutting force and wear test and surface roughness test from optimized and conventional cutter with the same cutting condition. Using various tools with different geometry, relationships between the tool geometry parameter, rake angle, clearance angle, lengh of cutter have been stuied.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.965-968
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• 1997

The objective of this study is to develop a rigid-thermoviscoplastic finite element program for the analysis of orthogonal cutting process. Deformation of the workpiece material is considered as rigid-viscoplastic and the numerical solution is obtained from the coupled analysis bctween plastic deformation and temperature field, including treament of temperature dependent material properties. The chip and the burr formation are simulated for the non-steady state orthogonal cutting using the developed program. To validate the program the predicted results at chip and burr format~on stage are compared with the published ones. The case of isothermal cutting process is also considered to study the thermal effect on the machining process.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1780-1783
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• 2003

Burrs formed in micro drilling with Ø 1.0 and 0.5 are observed. The changes of burr geometry are compared when feed rate and velocity changes. Characteristics of burr formation in 4 different workpiece materials are analyzed. The coefficient of burr geometry, CB is introduced to classify burrs according to burr height and burr types. Finally control charts are produced using the coefficient of burr geometry and burr types in each workpiece material. Data base is constructed to be used for burr expert system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.951-954
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• 2003

Generally, for the burrs formed in machining are irregular and very sharp in shape, it is usually very difficult to measure burr accurately. But, it is proved that precision measurement for micro burr using the conoprobe sensor by conoscopic holography method is possible. We developed 3D burr measurement system using this sensor. The system is composed of Conoscopic laser Sensor, X-Y table, controller and 3D measurement program. Some measurements using the developed system are applied to burrs formed in micro drilling and piercing.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.101-102
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• 2006

XML 기반의 Single Window은 국제 표준에 입각하여 해운 분야의 전자문서를 사용하여 국제해사기구와 전세계적으로 공통된 양식을 사용한다. 이는 동일한 양식의 전자문서를 사용하는 사용자들 간은 통용될 수 있다는 의미이며, 민원인 입장에서는 정보의 재사용성과 중복 입력의 불합리함을 줄일 수 있다. 이로써 민원인들은 입출항 수속 간소화 뿐만 아니라 해운 업무 자체에 많은 업무 개선 효과를 볼 수 있다. 본 고에서 제안한 XML 인프라스트럭처(XML infrastructure for Single Window)는 ebXML 기반의 Single Window에 적합하도록 설계 및 구현되었으며, 자원의 재사용성과 중복 투자를 방지할 수 있도록 하였다. 즉, 사용 환경에 유동적으로 적용가능 하도록 컴포넌트 방식으로 구성되었으며, 기존 시스템을 최대한 활용하도록 구성할 수 있도록 하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.911-914
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• 1997

This Experiment was carried out for bur minimization in drilling. New drill geometries are proposed to minimize the burr formation in drilling operation. Three types of drills are made, champer, round and step drill. The burr formed in first cutting by front cutting edge ca be removed in second cutting by the cutting edges in chamfer, round edge and step. New burrs are formed by second cutting and can be minimized according to the change of drill geometry like, chamfer size and angle, corner radius in round drill and step size and angle in step drill. To measure the burr formed in drilling, laser sensor is used.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.141-144
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• 2003

This paper proposes an analytical model of off-line feed rate scheduling to obtain an optimum feed rate for high speed machining. Off-line feed rate scheduling is presented as an advanced technology to regulate cutting forces through change of feed per tooth, which directly affects variation of uncut chip thickness. In this paper, the feed rate scheduling model was developed using a mechanistic cutting force model using cutting-condition-independent coefficients. First, it was verified that cutting force coefficients are not changed with respect to cutting speed. Thus, the feed rate scheduling model using the cutting-condition-independent coefficients can be applied to set the proper feed rates for high speed machining as well as normal machining. Experimental results show that the developed fred rate scheduling model makes it possible to maintain the cutting force at a desired level during high speed machining.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.873-876
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• 2003

Z-map model is the most widely used model for NC simulation and verification. But it has several limitations to get a high precision, to apply 5 axis machining simulation. In this paper, we tried to use quadtree for searching cutting region. Quadtree representation of two dimensional objects is performed with a tree that describes the recursive subdivision. By using these quadtree model. storage requirements were reduced. And also, recursive subdivision was processed in the boundries, so, useless computation could be reduced, too. To get more high Accuracy, we applied the supersampling method in the boundaries. The Supersampling method is the most common form of the antialiasing and usually used with polygon mesh rendering in computer graphics To verify quadtree model we compared simulated results with z-map model and enhanced z-map model