• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 추계학술대회(한국공작기계학회)
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• pp.344-348
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• 2001

In this study, experiments were carried out to investigate the characteristics of grinding and wear process of diamond wheel grinding ceramic materials. Normal component of grinding resistance was decreasing while increase of spindle speed. The resistance of vitrified bond wheel was less then that of resinoid bond wheel because of imbedded large holes on the surface of cutting edge. Surface roughness was decreasing while increase of spindle speed. The surface roughness after using vitrified bond wheel was less than that of resinoid bond wheel because of small elastic deformation. After continuous grinding of ceramics, cutting edge ratio of resinoid bond wheel decreases. For the case of vitrified bond wheel, cutting edge ratio does not change.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.832-836
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• 1997

An experimental study on the grinding temperature, surface roughness and Acoustic Emission(AE) signal was conducted with different shapes of wheel. The grinding characteristics by slotted shapes of wheel changed by width and helical angle,were compared with those by general one. Lower grinding temperature was obtained for 30 .deg. helical angel with 10mm width and Root Mean Square(RMS) values of AE signals were lower for slotted shapes rather than general one. Surface roughness characteristic of slotted shapes found to be rough,but the value of roughness for 45 .deg. helical angel with 6mm width, represented to similar tendency general one.

• 한국생산제조학회지
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• 제21권3호
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• pp.394-400
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• 2012

Due to the increasing demand for carious methodologies, the quality improvement of products were introduced. A brush, the most frequently used type of grinding process, is one of the deburring. In order to produce consistent burr shape, various machining conditions have been combined and applied to disk grinding process. By tool dynamometer, acoustic emission sensor and acceleration sensor depend on changes in processing conditions(depth of engagement, cutting speed, workpiece position, workpiece orientation, cutting time) signals were obtained for brush deburring grinding system. Root mean square obtained by processing the signal processing conditions by analyzing the characteristics of deburring is to derive the optimum conditions.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.155-159
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• 2002

This paper has studied to obtain the grinding characteristics and optimal grinding conditions of ceramics in the grinding with diamond wheel by Taguchi method. Feed rate was most important factor to the surface roughness. In the case of 4{Si_3}{N_4}$ and ${A1_2}{O_3}$, surface roughness value were small at 3m/min of feed rate. In the case of $ZrO_2$. surface roughness value was small at 4m/min of feed rate. Surface roughness have much influenced by major load for the :ii3N4 and $ZrO_2$. On the other hand, ${A1_2}{O_3}$ have more influenced by grain shedding of brittle fracture phenomenon. The major factors affecting the surface roughness and the optimum grinding conditions were obtained with minimum experiment using Taguchi method.

• 한국정밀공학회지
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• 제22권6호
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• pp.61-69
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• 2005

This paper presents the experimental results to analyze the atomization characteristics and environmental impact of cutting fluid in grinding process. Grinding is a major machining process to improve surface quality with different machining mechanism which is compared with turning or milling process. The environmental impact due to aerosol generation via grinding process is a major concern associated with environmental consciousness. Experimental results show that the generated fine aerosol which particle size less than 10 micron appears near working zone under given operational conditions. The aerosol concentration is much higher enough to affect human health risk with its generated aerosol quantities. This study can be provided a basic knowledge fur further research of environmental consciousness machining development.

• Design & Manufacturing
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• 제17권2호
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• pp.42-46
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• 2023

Currently, fossil resources are depleting rapidly. We are looking for energy to replace fossil fuels. They are trying to use electricity to replace internal combustion locomotives. Secondary battery raw materials and chemical additives are pulverized by the high-speed rotation of the grinding disc of the Classifier Separator Mill. Grinding Disc Assembly requires characteristics to withstand abrasion, corrosion, high-speed rotational force and impact. Domestic and foreign grinding discs were analyzed through abrasion resistance, hardness, bending strength, and tensile adhesion strength tests.

• 유기물자원화
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• 제18권2호
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• pp.93-100
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• 2010

본 연구는 하수슬러지 전처리 방법으로 분쇄, 동결 해동, 동결 분쇄 조작을 한 후, 각각의 슬러지 특성의 변화를 고찰하였다. 분쇄 슬러지, 동결 해동 슬러지, 동결 분쇄 슬러지는 하수슬러지 부피에 비해 각각 2.08배, 3.37배, 3.54배 감소하여 동결 분쇄한 경우가 가장 슬러지 감소량이 컸으며 그 다음으로 동결 후 해동한 경우, 분쇄만 한 경우 순이었다. 또한 하수슬러지의 SCOD 농도, SBOD 농도, protein 농도는 동결하지 않은 것보다 동결 하는 것이 높았고, 그 중에서도 동결 후 분쇄하는 것이 가장 높은 경향을 보였다. TS, VS의 제거율은 동결한 것이 높았지만, 동결 분쇄보다 동결 해동이 높은 경향을 보였다. 이상의 결과로부터 동결 분쇄 방법이 슬러지 전처리 방법으로 매우 효과적이며 2012년부터 발효되는 슬러지 해양 투기 전면 금지에 대한 대안이 될 수 있을 것으로 기대된다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.422-427
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• 2003

Sapphire have been ground by the ultra-precision surface grinder having a glass -ceramic spindle of extremely-low thermal expansion with various cup-type resinoid-bonded diamond wheels of #400-#3000 in grain size. Sapphire can be ground in the ductile mode. And also, the surface roughness and grinding conditions has been clarified. The smooth surface of Sapphire less than 1nm RMS, 1nm Ra can be obtained by the ultra-precision grinding without any polishing Process.

• 한국식품영양과학회지
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• 제39권7호
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• pp.1005-1010
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• 2010

본 연구에서는 인삼의 유용성분 강화 및 인삼 전근 활용을 위한 증숙 및 습식분쇄 조건을 조사하였다. 그 결과 무처리(A), $95^{\circ}C$/3 hr(B) 및 $121^{\circ}C$/15 min(C)의 증숙조건에 의해 각각의 당도는 7.7, 10.7 및 $11.2^{\circ}Brix$, 갈색도 0.37, 1.97 및 1.50로 증숙구간에서 당도 및 갈색도가 높게 나타났다. 조사포닌 함량은 7.19(A), 6.99(B) 및 8.83 mg/g(C)으로 C 조건에서 가장 높게 나타났다. 관능검사를 실시한 결과 C 조건에서 쓴맛 감소, 단맛 강도 및 전반적 기호도가 가장 높게 나타나 증숙처리 조건에서 관능적인 특성을 향상시킬 수 있었다. 가수량에 따른 습식분쇄 조건을 조사한 결과 가수량 300%에서 입자가 가장 작게 나타났다. 인삼의 습식분쇄조건은 분쇄 30분 및 3회에서 분쇄효율이 높았으며 평균입자크기는 $67.66\;{\mu}m$로 미세화되었다. 분쇄시간 및 횟수에 따른 유효성분 함량은 큰 차이가 없었다. 이상의 결과 증숙처리($121^{\circ}C$/15 min) 및 습식분쇄는 인삼의 전근 활용 및 유효성분 강화에 효과적인 것으로 확인되었다.

• 한국재료학회지
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• 제23권2호
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• pp.89-97
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• 2013

The study of grinding behavior characteristics on aluminum powders and carbon nano tubes (CNTs) has recently gained scientific interest due to their useful effect in enhancing advanced nano materials and components, which significantly improves the property of new mechatronics integrated materials and components. We performed a series of dry grinding experiments using a planetary ball mill to systematically investigate the grinding behavior during Al/CNTs nano composite fabrication. This study focused on a comparative study of the various experimental conditions at several variations of rotation speeds, grinding time and with and without CNTs. The results were monitored for the particle size distribution, median diameter, crystal structure from XRD pattern and particle morphology at a given grinding time. It was observed that pure aluminum powders agglomerated with low rotation speed and completely enhanced powder agglomeration. However, Al/CNTs composites were achieved at maximum experiment conditions (350 rpm, 60 min.) of this study by a mechanical alloy process for Al/CNTs mixed powders because the grinding behavior of Al/CNTs composite powder was affected by addition of CNTs. Indeed, the powder morphology and crystal size of the composite powders changed more by an increase of grinding time and rotation speed.