• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.63-68
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• 1996

In this study, the effect of tool rake angles and the change of cutting conditions on specific cutting pressure in face milling is investigated. The cutting force in face milling is predicted from the double cutting edge model in 3-dimensional cutting. Conventional specific cutting pressure model is modified by considering the variation of tool rake angles. Effectiveness of the modified cutting force model is verified by the experiments using special face milling cutters with different cutter pockets and various rake angles. From the comparison of the pressented model and the specific cutting pressure, it is shown that the axial force can be predicted by the tangential and redial forces without the knowledge of friction angle and shear angle. Also, the relation between specific cutting pressure and cutting cindition including feedrate, cutting velocity and depth of cut is studied.

• 한국정밀공학회지
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• 제12권11호
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• pp.63-73
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• 1995

A mechanistic force system model considering the flank wear for the face milling process has been developed. The model predicts variation of the cutting forces according to flank wear in face milling over a range of cutting conditions, cutter geometries and cutting process geometries including relative positions of cutter to workpiece and rounouts. Flycutting and multitoth cutting teste were conducted on SS41 mild steel with sintered carbide tool. In order to verify the mechanistic force model considering the flank wear of cutting tools, a series of experiments was performed with single and multitooth cutters in various cutting conditions. The results show good agreement between the predicted and measured cutting force profiles and magnitudes in time and frequency domains.

• 한국생산제조학회지
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• 제5권3호
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• pp.73-79
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• 1996

In this paper present a new technique (strain-telemetering)for detection of coated tool failure in face milling processes. In the cutter body the strain signals received fro the transmitter is transformed in to frequency modulation(FM) signals in face milling processes. A receiver which is place near by the Vertical milling machine receives the FM signals, then the signals will be sent to a computer which determines whether th tool is failure. And machined surface of workpiece is detected by the SEM. In this paper, A on-line monitoring of the tool failure detection system based on the strain -telemetering apparatus has bee represented.

• 한국정밀공학회지
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• 제13권4호
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• pp.87-96
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• 1996

On face milling operation a newly optimal tool, which can minimize the resultant cutting forces resulted from the cutting force model, was designed and manufactrued. Cutting experiments using the new and conventional tools were carried out and the cutting forces resulted from those tools were analyzed in time and frequency domains. The performance of the optimized cutter was tested through the dynamic cutting forces resulted form the newly designed tool are much reduced in comparision with those from the conventional tool. By reducing the dynamic cutting force fluctuations, machine tool vibrations can be reduced, and stable cutting operation can be carried out.

• 자동차안전학회지
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• 제7권2호
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• pp.8-14
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• 2015

The objective of this study was to construct the spring-mass models for the car-to-car frontal impact crash. The SISAME software was utilized to extract the spring-mass models using the data from US-NCAP frontal crash tests. The spring-mass models of a compact car and a midsize car could effectively approximate the crash characteristics for the full frontal barrier impact and the car-to-car frontal impact scenarios. Compared to the barrier crash tests, the dummy injuries of midsize car decreased, while the dummy injuries of compact car increased, under the frontal car-to-car crash circumstances.

• 한국기계가공학회지
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• 제4권3호
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• pp.57-62
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• 2005

Neural networks, which have learning and self-organizing abilities, can be advantageously used in the pattern recognition. Neural network techniques have been widely used in monitoring and diagnosis, and compare favourable with traditional statistical pattern recognition algorithms, heuristic rule-based approaches, and fuzzy logic approaches. In this study the fault diagnosis of the face-milling using the artificial neural network was investigated. After training, the sample which measure load current was monitored by constant output results.

• 한국기계가공학회지
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• 제16권4호
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• pp.24-29
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• 2017

This paper provides an experimental analysis on the breakage of the coated tool using the face-milling cutter of the machining center due to changes in the cutting speed and the feed rate. The experimental studies were conducted using STS 304 materials and the damage to the tool was analyzed according to the change in machining time. The experiments confirmed that the cutting speed and feed rate affected the tool damage and the mechanical impact and thermal shock were determined to severely damage the tool. From the production engineering point of view, it has been experimentally investigated that the increased feed rate significantly influences the material removal rate more than the increased cutting speed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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• pp.262-262
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• 2004

오오스테나이트 스테인리스강은 강도, 연성, 인성, 내식성 등이 우수하여 광범위하게 사용되고 있지만 절삭 시 전단저항이 크므로 절삭날 결손이나 용융을 유발하여 가공면을 안정시키기 어려우며 난삭재로서 가공경화가 매우 큰 재료이다. 그리고 질소를 약 0.1wt.％ 첨가한 316LN강은 316L강에 비해 고온강도 특성이 우수하여 주목받고 있는 새로운 재료이이지만, 저탄소의 강도 약점을 보완하기 위하여 고용강화원소로 질소를 첨가하기 때문에 높은 강도로 인하여 절삭가공에 난점이 있으므로 이 재료를 응용하기 위해서는 절삭 시 재료 표층부에 발생하는 가공 변질층에 관한 연구가 필요하다.(중략)

• 대한교통학회:학술대회논문집
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• 대한교통학회 1998년도 제34회 추계 학술발표회
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• pp.409-409
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• 1998

본 연구는 운전자 특성 및 교통사고 발생유형에 따른 사고 심각도(Severity)를 분석함으로써 교통사고를 유발키 쉬운 운전자 집단과 사고 발생시 위험도가 높은 사고유형을 규명하고자 하였다. 교통사고 위험집단 분석을 위한 운전자 특성은 성별, 차종, 연령 등을 대상으로 하였으며, 사고유형별 심각도 분석은 사고유형을 여덟 가지로 분류하고, 결과의 신뢰성 확보를 위하여 안전벨트 착용여부를 추가하여 상해정도와의 관계를 비교하였다. 로그-선형 모형 및 로짓 모형을 사용하여 카테고리 자료를 분석하였으며, 그 결과 위험집단 분석에서는 '20세 미만의 이륜차 운전자', '41세에서 50세까지의 택시운전자'가 가장 위험한 것으로, 또한 남자보다는 여자가 승용차, 택시, 이륜차 등에 관계되었을 때 위험한 것으로 조사되었다. 사고유형과 심각도와의 관계에서는 정면충돌 사고와 앞지르기 시 우회전시 사고가 기여위험도(Odds Multiplier)가 매우 높아 부상 또는 사망사고와 연계될 가능성이 큰 것으로 나타났다. 따라서 교통사고의 예방과 사고발생시의 심각도 경감을 위해서는 교통사고 취약계층으로 분석된 위험집단에 대한 교통안전 교육 및 홍보가 강화되어야 하고, 정면충돌 사고와 앞지르기 시 우회전시 발생하는 사고를 줄일 수 있는 방안이 연구되어야 할 것이다.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2002년도 춘계학술대회 논문집
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• pp.234-239
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• 2002

한국인 인체모델은 동적 환경에서 정면 및 측면 충돌에 대한 지체의 가속도를 얻을 수 있도록 개발되었다. 우선 GEBOD에 입력하기 위한 32개의 한국인 인체치수를 선별하고, 15개의 지체를 가진 한국인 인체모델을 구성한다. 손 동작의 감성평가에 이용하기 위해 손을 독립된 지체로 분리한 17개 지체의 인체모델을 완성한다. MADYMO를 통한 정면충돌 테스트에서는 Hybrid III에 비해 한국인의 머리와 흉부 가속도가 비교적 높게 나왔고, 측면충돌 테스트에서 흉추 1번의 가속도는 ISO에서 요구하는 범위의 상한값을 조금 벗어나는 결과를 얻었다.