• 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.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.5
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• pp.41-50
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• 2000

NC(Numerical Control)는 1949년 미 공군이 Parson (Fig. 1 (a))이라는 사람에게 프로펠러 (Propeller)용 블레이드(Blade)의 윤곽을 검사하기 위한 판 게이지(Gauge)(Fig. 1 b)) 개발을 의뢰한 것이 계기가 되어 발명되었다. 이후, 신시나티 미라크론(Cincinati Miracle)이라는 공작기계 업체가 NC 사업에 참여하게 되고, 1952년 최초로 MIT(Massachusetts Institute of Technology)의 서보기구연구소(Servo-mechanism laboratory)에 의해 NC 공작기계가 탄생(Fig. 1 (c)) 되었다.(중략)

• Journal of the KSME
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• v.18 no.2
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• pp.71-75
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• 1978

최근 기계공업분야에서 수직제어공작기계란 말이 매우 주목을 끌게 되었다. 그래서 기계공업의 형태에 있어서는 NC기술과 NC공작기계가 매우 중요한 역할을 하리라 예상된다. 그 까닭은 현 재 공산품의 질과 재료에 있어서 NC공작기계가 그 주역을 담당해 가고 있기 때문이다. 다년간 인간이 경험적으로 축적해온 종래의 기계체조기술에다 최근 쉴새없이 진행되는 기술혁신과 특히 비약적인 발전을 거듭하는 전자기술 그리고 그 제품들을 기계에 활용하므로써 NC공작기계 는 드디어 두뇌산업의 기수라고 해도 과언이 아닐 것이다. 따라서 NC기술과 NC공작기계가 그렇게 중요시되는 이유와 전망을 살펴보기로 한다.

• Food Science and Preservation
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• v.15 no.6
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• pp.897-902
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• 2008

The effect on serum lipid of green aster juice blended with ginseng and carrot extracts was investigated using rats injected with $CCl_4$. The rats were classified with four groups: (i) normal control (NC), (ii) rats fed with the blended juice (BA), (iii) rats treated with $CCl_4$ after having been on a normal diet for 4 weeks ($NC-CCl_4$), and (iv) rats treated with $CCl_4$ after having been fed the blended juice for 4 weeks ($BA-CCl_4$). All groups had similar feed intake. The weight gains and feed efficiency ratio were lower in the $NC-CCl_4$ group. The liver weight per body weight was much higher in the $NC-CCl_4$ group than the NC group, but did not differ between the $BA-CCl_4$ and BA groups. Triglycerides increased only for the $NC-CCl_4$ group (88.72 mg/dL); the other groups had similar levels (56.48-65.33 mg/dL). The BA group had the lowest total cholesterol level (74.08 mg/dL) the other groups had similar levels (96.78-108.83 mg/dL). HDL-cholesterol was lower in the $NC-CCl_4$ group (40.56 mg/dL) compared with the NC group (48.95 mg/dL), but there was no difference between the BA and $BA-CCl_4$ groups. The LDL-cholesterol level was higher in the $NC-CCl_4$ group (55.20 mg/dL the highest level) than the NC group (43.33 mg/dL), and higher in the $BA-CCl_4$ group (50.10 mg/dL) than the BA group (18.09 mg/dL). The lipid peroxide content was much higher in the $NC-CCl_4$ group (22.61 nmol/g) than the NC group (12.52 nmol/g), but the $BA-CCl_4$ (17.41 nmol/g) and BA (13.99 nmol/g) groups were similar. The glutathione content was much lower in the $NC-CCl_4$ group ($2.25\;{\mu}mol/g$) than the NC and BA groups, and decreased to $2.63\;{\mu}mol/g$ for the $BA-CCl_4$ group. The glutathione content of the $BA-CCl_4$ recovered to the level of that in the NC group.

• Korean Journal of Computational Design and Engineering
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• v.8 no.1
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• pp.48-54
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• 2003

In a design-to-manufacturing environment, the product data is shared by various CAD/CAM/CAE systems with little integration or substantial data redundancy. The main purpose of this paper is to build a database containing all the features required for STEP-NC machining and to show how a STEP-NC repository can support the complete process for machining. A STEP-NC database schema has been constructed and several query functions have been built for the purpose of implementing the retrieving system of a STEP-NC database. The EXPRESS data model of ISO 14649 has been mapped to the database data definition language of the Oracle database. To apply the STEP-NC database to an industry example, the ISO 14649 part program has been stored into the STEP-NC database. To implement example scenarios, the sample query interface has been built.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.308-312
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• 1989

We developed a model of NC controller with IBM-PC as a host cpu and integlligent NC servo controller for 2 axes that can be expaned to 4 axes. Basic conceptions, including hardware structure design, servo controller design, communication protocol, and interpolation hardware design was already publicated on '87 KIEE conference. Following this, we focussed on the emulation of tyhe controller with X-Y table as complete NC machine experimenting some drawings made by NC code program that can be edited and executed in automatic on single step mode. In addition we designed the M.S.T functions with PLC and tested for M-function timing. Finally, we designed NC interface to fit with M-function output and we contructed total system of NC controller with IBM PC host with the result of successful development of new NC model.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2297-2311
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• 1994

This paper presents the study on the development of a DNC, system IPIS(Interactive Plant Information System)/DNC, which can manage NC machines and robots as a distributed control method in the machine. processing factory. The IPIS/DNC system is composed of a host computer, satellites and NC machines. A set of software modules are developed on the host computer and the satellites separately. By modularizing each functions of the IPIS/DNC system and using multi-taking method, the functions such as NC program management, NC program distribution, and shop monitoring can be performed on the host computer, and the functions such as NC program transfer to the NC machines, and NC program editing can be performed on the satellites. A Relational database which is linked with job scheduling system is used for IPIS/DNC system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1992.04a
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• pp.148-152
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• 1992

수치제어(NC: numerical control) 기술은 공장자동화를 위한 중요기술이다. 우리산업현장에 공장 자동화가 확장되면 서 NC 공작기계산업용 로봇, 삼차원 좌표측정기 등의 사용이 매우 증가되고있다. 이러ㅗ한 수치제어용 기계에서는 자동 위치제어를 위하여 길이변위와 회전각도감지용센서인 NC 엔코더가 매우 중요한 부품이다. NC 엔코더에는 선형 엔코더( NC-스케일)와 회전 엔코더가 있으며, 각각 직선운동과 회전운동을 제어하기위해서 필요한 자동화 부품이다. 선형 엔코 더는 직선운동의 변위를 감지하며 NC-스케일 이라고도 말한다. 우리 나라에서는 아직 엔코더 제작기술을 개발하지 못하여 전량수입에의존하고 있다. 이러한 NC 엔코더의 수요는 해외시장뿐만 아니라 국내시장에서도 급격히 증가 되고있으며 국산화 개발이 시급하다. 이 글에서는 NC-스케일 제조기술을 개발함에있어서 연구하였던 참조위치 마크(Rrference Mark)설계 기술을 정리한다.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.5
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• pp.116-123
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• 2000

This paper presents an NC code post-processor that adjusts feedrates to keep the variation of metal removal rate along the tool paths minimum. Metal removal rate is estimated by virtually machining the part, whose surface model is built from a series of NC codes defined in operation plan, with cutting-tool-assembly models, whose geometry are defined in a machining database. The NC code post-processor modifies the feedrates by the adjustment rules, which are based on the machining knowledge for effective machining. This paper illustrates a procedure fur grouping machining conditions and we also show how to determine an adjustment rule for a machining-condition group. An example part was machined and it shows that the variation of cutting force was dramatically reduced after applying the NC code post-processor. The NC code post-processor is expected to increase productivity while maintaining the quality of the machined part.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.5
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• pp.21-26
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• 2005

It is important to measure the rotational accuracy of NC lathe spindle as it affects to the qualities of all machines machined by the NC lathe using in industries. The bad rotational accuracy of NC lathe spindle are caused mainly by wearness of the spindle in using and quality of spindle when machining and using low level bearings. It occurs especially in case of NC lathes because the cutting force acting to work-piece act on one side to the spindle not to both sides symmetrically. Therefore in this study, constructing experimental appratus for measuring of rotational accuracy by using eddy current type gap sensors, converters, screw terminal, data acquisition board inserted in computer and software f3r data acquisition, DT VEE ver. 5.0 and then error data acquired in the rotational accuracy test of NC lathe spindle are analysed in plots and statistical treatments.