• Korean Journal of Computational Design and Engineering
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• v.6 no.1
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• pp.1-8
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• 2001

We developed an on-line lathe simulator which can be used for a CAM education on the internet. Previously, VRML or static images such as JPG have been commonly used to achieve the same goal. With the 3D tool like VRML, it was possible to describe the movement of 3D object effectively. However, G-code based modeling and real-time visualization for the cutting process including parts being machined could not be accomplished. By using the simulator, we can machine a part with G-code input from a user or modeler, and parts being machined can be visualized in 2D as well as 3D. The developed system is based on EMCO lathe from Eshed and can be used through a web browser.

• The Korean Journal of Ecology
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• v.13 no.3
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• pp.181-190
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• 1990

Chodo Archipelago ($125^{\circ}$45 $-126^{\circ}$13 E and $34^{\circ}$15 $-34^{\circ}$25 N, ca. $56.7km^2$), a part of the Dadohae National Marine Park, largely is covered with substitutional vegetation under various human impact such as grazing, cutting for firewood. However natural vegetation is partially distributed in the tutelary shrine forests, deep valleys and etc. From October 1988 to June 1989, phytosociological investigation of this forest vegetation was carried out by Braun-Blanquet s method. The forest vegetation was classified into 1 association and 7 communities. Ardisio-Castanopsietum sieboldii, Machilus thunbergii, Quercus acuta, Litsea japonca, Eurya japonica-Pinus thunbergii mixed forest, Pinus densiflora, Pinus rigida afforestation. Carpinus coreana community. Based on the classification, the actual vegetation map was drawn in 1 : 50,000 scale.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.88-93
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• 2001

As the development of High Speed Machining, It is applied in many fields of manufacturing. Among them is to manufacture die and mold. But it still remains as a hard-to-work to apply it in machining pre-hardened materials such as hardened QRO90. It also difficult to machine new materials because there is no machining date of them. Therefore, in this study, we are trying to improve the machinability of new material, QRO90 by applying various cutting conditions, and selecting the best condition which not only reduce the machining time but improve the quality of die and mold made of QRO90 material.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.2
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• pp.1-8
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• 2003

Conventionally used linear or circular interpolator is undesirable for the precision machining of 3D free-form surface as the following reason: the transmission errors due to the huge number of data, discontinuity of segmentation, unsmooth motion speed. To this regard, modern CNC machine tools are designed with the function of machining arbitrary parametric curves. However, these systems don't consider the adaptive federate, which dominates the quality of the machining process. This paper proposes a NURBS interpolator for the constant material removal rate. That is accomplished by the variable federate using curvature of curve. The curvature-compensated feederate system has important Potential applications in ensuring part accuracy and protecting cutting tool. The simulated result show it can be applicable to the real machining.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.4
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• pp.114-120
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• 2000

Burr is an unavoidable and undesirable by-product of most metal cutting or shearing operations. This burr must be removed to improve the fit of machined parts and safety of workers, to improve the effectiveness of finishing operations. Despite the full or partial automation of FMC or FMS, deburring operations to obtain workpiece with fine surface quality are difficult to be automated since the occurrence and condition of burr are not constant. This study focused on developing a software for deburring automation, which includes automatic recognition of parts, generation of deburring tool path and NC code, by analyzing the IGES format file which contains information of part geometry. The successful performance of developed software was demonstrated by computer simulation and deburring experiment using miniature end brush. And, this research can provide a basis for further advanced studies for automated deburring applications.

• Journal of the Korean Society of Safety
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• v.7 no.4
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• pp.95-99
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• 1992

The attraction of using expert system in operator support systems for modern plant is that it offers a way of dealing with the problem of information overload that can occur during a severe disturbance at a modern industrial plant. During such a disturance the volume of information presented to operators may be such that they are unable to decide quickly what is important and what is not. Therefore, arriving at a correct diagnosis of the initialling fault may be delayed. An expert system operator sup-port system is a means of focusing attention on what really matters and cutting out the rest. This paper presents the development of prototype expert system which detect the fault part, machine, system and decide action priority. This prototype expert system has 6 sub- system which is Interface Manager, Decision Maker, Inference Engine, Knowledge base, Simulatio, and D.P System ( Diagnosis and predictor)

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.4
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• pp.316-333
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• 2005

Although some successful recognition algorithms have been developed, most of them did emphasize on extracting accurate interpretations without considerations of manufacturability. Evaluating the manufacturability for multiple features leads to produce the machining sequences. In this paper, the A* algorithm guarantees the optimal setup sequences with minimizing the machining cost. Also, tolerances including surface roughness are converted to STEP formats to be utilized for more reliable process plans. Finally, decision tables are used to create the detailed operational sequences based on geometric tolerances and surface roughness. Machining parameters such as feed, depth of cut, and cutting speed for each operation are added to the routing sheet. Windows are presented to show how the entire system works for a sample part.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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• pp.1347-1354
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• 1994

This paper deals with the experimental research, including measurement and analysis and field survey, on the causes of occurring noise defective gear boxes in hoist production plant in order to reduce the fraction of their occurrence. In this reserch following investigations are performed : measurement and gear-boxes, examination of each machining process of production, measurement and analysis of dimensional accuracy of each part, comparative vibration test with exchanging inaccurate parts. From these investigations, it is found that the machining accuracy of pinion gear tooth thickness is the most sensitive factor of noise problem. By maintaining the tooth thickness error within 0.05 mm tolerance in the gear cutting process, the fraction of noise defective gear-boxes are greatly reduced to less than 2%, where the usual rate of it has been 20-50%.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.6
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• pp.43-50
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• 2010

This study aims to analyze the structural safety by comparing deformation and equivalent stress of door with a stiffener or no stiffener when the door crashes against something in case of overturn. Three types are classified on the basis of the no stiffener model in the vehicle door. One is the type which has a stiffener. Another is the type which has no stiffener and the other is the type which has a hole in the stiffener. These three types are compared with each other by analyzing. This side door of vehicle is the automotive part about the kind of vehicle as Mercedes Benz E-Klasse scaled down as 1/18 times as the real size. The study model of vehicle door is modelled by CATIA program and it is analyzed by ANSYS.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.12 s.189
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• pp.30-37
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• 2006

In this work, the surface integrity smoothened with a ball end mill was investigated. Because surface integrity mainly affects the manual finishing process, $RV_{AM}$(Remaining Volume After Machining) was introduced, and it gives the relation between machining process and finishing process. Runout and phase shift which adversely affect surface integrity were considered in the generation of surface topography. Cutting points in ball end milling were identified with positional vectors and a set of vectors which have the minimum height in unit area was selected for the generation of surface and $RV_{AM}$. $RV_{AM}$ variation according to runout and phase shift was calculated and experimentally verified in proposed HSM conditions for mold machining. From the simulations and the experiments, a desirable High Speed Machining condition was suggested.