• Journal of the Korean Society for Precision Engineering
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• v.13 no.7
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• pp.24-28
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• 1996

In this paper, a new measurement system has been developed for measuring servo errors of CNC machine tools. Unlike the ball link bar method using circular path, the developed system uses two orthogonal straight paths for measurement of errors, giving relatively short test length. For position measurment, linear displacement sensor and steel cube have been designed, and the software for relevant data sampling and error evaluation has been implemented.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.292-297
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• 2004

The conventional computerized numerical controller (CNC) of machine tools has been increasingly replaced by a PC-based open architecture CNC (OAC) which is independent of the CNC vendor. The OAC and machine tools with OAC led the convenient environment where it is possible to implement user-defined application programs efficiently within CNC. Tis paper proposes a method of operational fault cause diagnosis which is based on the status of programmable logic controller (PLC) in machine tools with OAC. The operational fault is defined as a disability state occurring during normal operation of machine tools. The faults are occupied by over 70% of all faults and are also unpredictable as most of them occur without any warning. Two diagnosis models, the switching function (SF) and the step switching function (SSF), are propose in order to diagnose the fault cause quickly and exactly. The cause of an occurring fault is logically diagnosed through a fault diagnosis system (FDS) using the diagnosis models. A suitable interface environment between CNC and develope application modules is constructed in order to implement the diagnostic functions in the CNC domain. The diagnosed results were displayed on a CNC monitor for machine operators and provided to a remote site through a web browser. The result of his research could be a model of the fault cause diagnosis and the remote monitoring for machine tools with OAC.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.1004-1009
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• 2009

Cultural products are created by hand in the overall consumption and high labor costs of a long time, and have the limitations of mass production. A large percentage of handicraft is wax-carving. This technique is difficult to express the small, detailed parts. This part of this to minimize the introduction of CNC system has to work with wax carving. this to CNC system has to work with wax carving minimize the introduction. Increase the accuracy of small and detailed parts. And various design and mass production will be efficient. In so doing, to enable the circulation of cultural products to have prepared.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.208-214
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• 2005

France is the country who maintains a strong protective policy in her culture area. Under the famous slogan of 'Cultural Diversity' or 'Cultural Exception,' France stands against the globalizing policy of USA. Also in the area of audiovisual contents, France maintains her protective policy in order to protect her cinematic territory against the invasion of Hollywood movies. Among the various supporting systems of French Government, we would like to pay closer attention to the supporting system for young film makers and the role of CNC (Centre National $Cin\`{e}matographique$) in this system. So, this article will examine how CNC, as a governmental agency, controls the supporting system in French audiovisual area, and what kinds of process it operates to offer the substantial aid to French young film makers' work.

• Special Issue of the Society of Naval Architects of Korea
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• 2011.09a
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• pp.101-105
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• 2011

In most shipbuilding company, cutting procedure is proceed by cutting machine which run by CNC(Computer Numerical Code) data. In our cutting process, all CNC data is created by our nesting post processor system automatically. Among them, in case that cutting piece in the remnant plate, our system creates only one piece CNC data. Because remnant plate is not typical shape, and ship designers don't know remnant plate shape and quantity. In can happen some merit and good point if we modify 1:1 piece NC data by shorten cutting path, reducing cutting time or re-arrangement piece. For modifying cutting data, outside workers have to call to ship designer or have to go to NC control room where control the CNC system and cutting machine. It makes stop work process, and it waste time. In this paper, we introduce a program that can modify and replace 1:1 NC data with continuous or common NC data automatically.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.17-18
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• 2008

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.1
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• pp.95-102
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• 2012

To examine the new practical utilization of mucilages in Opuntia humifusa, the Korean pear cactus, the polysaccharides were isolated from O. humifusa, and immuno-stimulating activities were assayed. The main polysaccharide, CNC-E, was prepared by a commercial enzyme treatment, water extraction, and ethanol precipitation. The molecular mass of CNC-E was estimated to be about 700 kDa, and it consisted mainly of arabinose, galactose and xylose in addition to two minor sugars such as rhamnose and fucose. On the other hand, CNC-E showed considerably high splenocyte proliferation activity in a dose-dependent manner. Peritoneal macrophages stimulated with CNC-E produced cytokines such as IL-6, IL-12, IL-10, and TNF-${\alpha}$. The intravenous administration of CNC-E significantly augmented the cytotoxicity of natural killer (NK) cells against Yac-1 tumor cells. Especially, NK cells obtained from the mice treated with $100{\mu}g$ of CNC-E showed threefold higher cytolytic activity than those of untreated mice. CNC-E also showed potent anti-complementary activity in a dose-dependent fashion. Identification of C3 activation products by the crossed immunoelectrophoresis using anti-human C3 and the anti-complementary activity of CNC-E in a $Ca^{2+}$-free condition suggested complement activations by CNC-E that occur via both alternative and classical pathways. These results indicate that Korean pear cactus contains selected polysaccharides that provide immuno-stimulating activities beneficial to human health.

• International Journal of Precision Engineering and Manufacturing
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• v.8 no.2
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• pp.59-63
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• 2007

We propose a controller design analysis for a cross-coupling control system, which is essential for achieving high contouring accuracy in multi-axis CNC systems. The proposed analysis combines three axial controllers for each individual feed drive system together with a cross-coupling controller at the beginning of the design stage in an integrated manner. These two types of controllers used to be separately designed and analyzed since they have different control objectives. The proposed scheme is based on a mathematical formulation of a three-dimensional contour error model and includes a stability analysis for the overall control system and a performance analysis in terms of contouring and tracking accuracy at steady state. A computer simulation was used to demonstrate the validity of the proposed methodology. The performance variation was investigated under different operating conditions and controller gains, and a design range was elicited that met the given performance specifications. The results provide basic guidelines in systematic and comprehensive controller designs for multi-axis CNC systems. A cross-coupling control system was also implemented on a PC-based three-axis CNC testbed, and the experimental results confirmed the usefulness of the proposed control system in terms of contouring accuracy.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.5
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• pp.447-454
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• 2015

Design and application of hardware-in-the-loop simulation (HILS) for design of CNC-controlled machine tool feed drives is discussed. The CNC machine tool is a complex mechatronics system where the complexity results from the software-based controller composed of a variety of functionalities and advanced control algorithms. Therefore, using a real CNC controller in the control simulation has merits considering the efforts and accuracy of the simulation modeling. In this paper challenges in HILS for a CNC controlled feed drive, such as minimization of time delay and transmission error that are caused by discretization of the feed drive model, is elaborated. Using an experimental HILS setup of a machine tool feed drive applications in controller gain selection and CNC diagnostics are presented.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.4
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• pp.19-26
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• 1997

The manufacture of an impeller typically requires the 5-axis CNC machining, since the impeller is usually under working conditions such as high speed, high temperature, and high pressure. Thus, this study contributes to development of an exclusive CAM system for effective 5-axis CNC machining of a ruled surface type impeller. In this study, the sampled impeller is made of blades and a body and the blade consists of ruled surfaces between hub curve and shroud curve. In the post processing for 5-axis NC part program, the cutter axis direction vector is the straighten vector on ruled surface. The position of ball center in ball end mill cutter is decided on the interference check between the cutter and body surface of impeller using with the modified z-map method that z-axis is the same of cutter axis direction vector. The exclusive CAM system for an impeller developed in this study was very effective for designs and 50-axis machining of a ruled surface type impeller.