• 한국정밀공학회지
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• 제27권1호
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• pp.58-63
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• 2010

A new contact force estimation technique is proposed. Keeping the contact force at a certain level between finishing tool and the object is essential since the quality of the finished surface is very sensitive to the contact force during the finishing process. However, the contact force measurement cannot be obtained by simply installing load cells under machine table or in the middle of tool linkage. The reason is that the weight of the machine table and the tool linkage are much heavier than the force to be measured. To that end, a method for estimating disturbance is proposed for a system that is similar to the mechanism of the finishing machine, and the same method is applied to estimate the contact force of the brush-type finishing machine. To verify the effectiveness of the proposed method, a small scale test set-up has been built and the method has been tested.

• 한국정밀공학회지
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• 제17권2호
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• pp.89-96
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• 2000

This paper describes the characteristic of die finishing to obtain smooth surface using electro-chemical grinding after cutting process. Electro-chemical grinding is possible under lower load and tool wear comparing with those in the mechanical grinding. Conventionally, if the metal bonding material of the grinding wheel is directly t contacted with workpiece, the current is circulated without electrolytic phenomena. Sometimes, electrical discharge is occurred between tool and workpiece. To cope with this problem, the metal-resin bonded pellet was used in this study. This pellet is composed of optimal volume of metal and resin powders and its characteristics are changable with the each volume of powders. Finally, high efficient die finishing is realized using metal resin bonded pellet in electro-chemical grinding.

• 한국잠사곤충학회지
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• 제5권
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• pp.47-51
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• 1965

생사정리방법이 재소검사성적에 미치는 영향을 조사하기 위하여 본 실험을 하였으며 얻어진 결과는 다음과 같다. 1. 단이 배이보다 절단경향이 적었다. 2. 타래의 표부보다 그 이부검사성적이 약배 나뻤다. 3. 시료 채취부위별 검사결과는 괄각부의 단절이 가장 많고 표부 내부의 순위로 되었다. 4. 검사시간이 경과함에 따라 단절이 감소하는 경향이었다. 5. 생사정리 부주의로 인한 재조절단발생률은 단이보다 배이에서 더욱 크게 나타난다. 6. 생사정리상 적합한 수분률은 10∼11%이다.

• 한국염색가공학회지
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• 제13권4호
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• pp.272-281
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• 2001

Shrink resist finishing of wool fabric was carried out with MONAMIN BTN shrink resist agent after chlorination with D.C.C.A.(dichloro isocyanuric acid). The purpose of this study is to investigate the effect of treating conditions, such as concentrations of D.C.C.A and MONAMIN BTN, pH of treating bath, dying times, curing times and temperatures, on shrink resist finishing. Mechanical properties of the treated fabric were measured by KES-FB system. The optimum chlorination of wool corresponds to 2∼3%(o.w.f.) of D.C.C.A. without rendering the damage on surface of wool fiber. Also it seems likely that the shirink resist finishing carried out at 2 ∼3%(o.w.f.) of MONAMIN BTN and pH 7∼8 of treating bath is effective in increasing a softness of hand.

• 한국건축시공학회지
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• 제15권6호
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• pp.607-614
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• 2015

일반적으로 건축물의 마감은 기본적인 발수성을 가진 수성페인트 마감으로 이루어진다. 이는 건축물 외벽에 작업시 적용하기 쉬우며, 건축물 유지 또한 쉬워 많은 장점을 가지고 있다. 하지만 자외선으로 인해 변색 또는 열화 되기 쉬워 그 효과는 기대에 미치지 못하고 있다. 따라서 본 연구는 외부 표면마감 재료로서 발수제를 직접 혼입한 수성페인트의 색 변화를 통한 내구성능을 분석하여 실제 현장에 적용하기 위한 실용성을 평가하고자 하였다. 촉진 시간에 따른 색 변화 및 색차를 측정하였으며, 적용가능성은 실험결과를 토대로 평가하였다. 색차, 명도 및 색도의 변화량을 실험결과에 따라 종합적으로 고려해 볼 때 본 연구에서 제안한 발수제를 혼입한 수성페인트 마감공법(혼입율 2, 5, 8%)은 충분히 사용 가능할 것으로 사료된다. 이는 건축물의 외부 표면을 수성페인트로 칠한 후 추가로 발수제를 도포하는 등의 기존 표면 마감방법에 비해 공사내용이 간편하며 시공성도 양호하여 폭넓은 활용이 기대된다. 또한 실제 현장에서는 원하는 색상으로 필요한 양만큼 제조하여 사용할 수 있으며, 전문 인력이 필요하지 않아 손쉽게 활용 가능할 것으로 기대된다.

• 한국구조물진단유지관리공학회 논문집
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• 제22권1호
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• pp.183-189
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• 2018

본 연구에서는 용사기법에 의해 콘크리트 표면에 금속피막을 형성하는 새로운 마감 의장기법의 가능성을 검토하기 위하여, 콘크리트의 함수율 변화에 따른 금속피막의 부착성능에 대하여 실험적인 연구를 수행하였다. 그 결과, 선재의 색은 용사 후에도 변하지 않는 것을 알 있었고, 콘크리트 부착강도 기준인 2.5 MPa를 확보하기 위한 하지 콘크리트의 함수율을 10% 이하로 관리하면 금속피막의 부착강도눈 확보되는 것으로 판단된다. 또한, 콘크리트와 금속피막의 부착강도를 증진시키기 위해서는 표면강화제에 의한 콘크리트 표면강화와 함께 금속피막을 봉공처리제로 봉공하는 것이 매우 유효한 것을 알 수 있었다.

• 한국표면공학회지
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• 제32권3호
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• pp.195-207
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• 1999

The use of multilayered electrodeposits, to enhance coating performance especially in corrosive environments, has uncertain origins but has been systematically practiced and optimized since the 1950s. The background to such systems will be traced, examples given of their usage, and the recent development of nanometre multilayers by pulsed plating techniques described.

• 한국세라믹학회지
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• 제46권1호
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• pp.102-107
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• 2009

This study has been focused on an effective surface finishing method combining ELID (ELectrolytic In-process Dressing) and MAP (Magnetic Assisted Polishing) for the nano-precision mirror grinding of glass-lens molding mould. ELID grinding is an excellent technique for mirror grinding of various advanced metallic or nonmetallic materials. A polishing process is also required for elimination of scratches present on ELID grinded surfaces. MAP has been used as polishing method due to its high polishing efficiency and superior surface quality. It also presents some techniques for achieving the nanometer roughness of the hard material such as WC-Co, which are extensively used in precision tooling material.

• 한국정밀공학회지
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• 제23권1호
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• pp.97-104
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• 2006

ELID(Electrolytic In-process Dressing) grinding is an excellent technique for mirror grinding of various advanced metallic or nonmetallic materials. A polishing process is also required for elimination of scratches present on ELID grinded surfaces. MAP(Magnetic Assisted Polishing) has been used as polishing method due to its high polishing efficiency and to its resulting in a superior surface quality. This study is describing an effective fabrication method combining ELID and MAP of nano-precision mirror grinding for glass-lens molding mould. It also presents some techniques for achieving the nanometer roughness of the hard metals, such as WC-Co, which are extensively used in precision tooling material.

• 한국안전학회지
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• 제17권3호
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• pp.30-35
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• 2002

The magnetic abrasive polishing is the useful method to finish using magnetic power of a magnet. It's not a long time this method was introduced to korea as one of precision finishing techniques. The magnetic abrasive polishing method is not so common for machine that it is not spreaded widely. The are rarely researcher in this field because of no-effectiveness of magnetic abrasive. The mechanism of this R&D is dealing with the dynamic state of magnet-abusive. This paper deals with mediocritizing magnetic polishing device into regular lathe and this experiment was conducted in order to get the best surface roughness at low cost. We need to continue the research on it. This paper contains the result of experiment to acquire the best surface roughness, not using the high-cost polishing material in processing. The average diameters of magnetic abrasive are the particles of 150$\mu\textrm{m}$, 250$\mu\textrm{m}$.