• 한국정밀공학회지
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• 제24권6호
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• pp.51-57
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• 2007

Creep-feed grinding is an effective technology processes to increase the productivity and efficiency in form grinding. This method has, however, some problems which the progress of abrasive wear around the cutting edge is remarkable, grinding force become intense and burn marks on the ground surface occur frequently. In order to solve this problems, it is proposed in this study to dress the grinding wheel continuously during the grinding process. The purpose of this research is. therefore, that CNC creep-feed grinding machine which has a continuous dressing device developed and some grinding experiments for determination of dressing conditions carried out.

• 한국정밀공학회지
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• 제18권9호
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• pp.18-24
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• 2001

• Journal of Korean Biological Nursing Science
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• 제5권1호
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• pp.23-33
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• 2003

본 연구는 체중 3.0kg의 가토 수컷 10마리를 이용하여 피부의 외상을 입힌 후 개방드레싱과 밀봉드레싱이 상처의 치유과정에서의 효과와 형태학적 차이를 비교하기 위해 1cm의 절개창과 $1.0{\times}0.2cm$의 피부절제창을 만든 후 개방드레싱군은 1일 2회 betadine으로 소독한 후 상처부위를 노출시켜 5, 10 및 15일째에 관찰하였으며, 밀봉드레싱군은 매일 betadine으로 소독하고 1% silver sulfadiazine 크림을 도포한 후 거즈를 덮어 5, 10 및 15일째에 광학현미경으로 관찰하여 다음과 같은 결론을 얻었다. 피부를 절개한 군과 절제한 군을 개방드레싱 및 밀봉드레싱을 각각 시행한 5일 후에는 딱지가 형성되었고 표피의 재생은 상처의 가장자리에서부터 시작하였다. 진피의 표층에는 호중구, 단구 및 림프구의 침윤이 일어났고 부종과 섬유아세포의 증식이 경하게 일어났다. 수상 후 개방드레싱 및 밀봉드레싱을 시행한 10일 후에는 딱지는 탈락되었고 표피는 재생되어 연속적이었다. 모세혈관의 수와 염증세포의 침윤은 감소하였다. 부종과 섬유아세포의 증식은 더욱 증가하였다. 수상 후 개방 및 밀봉드레싱을 시행한 후 15일에는 표피의 재생은 완성되어 각질이 형성되었다. 진피에는 염증세포의 침윤, 부종 및 혈관의 증식은 소실되었고 섬유아세포 및 교원섬유의 양은 증가하였다. 피부를 절개한 군은 절제 군에 비해 반흔의 양은 적었고 드레싱방법에따른 치유과정의 차이는 없었다. 이상의 성적으로 보아 상처의 치료는 드레싱의 방법보다 상처의 소독이 중요한 역할을 하는 것으로 사료된다.

• 대한기계학회논문집A
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• 제21권8호
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• pp.1298-1310
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• 1997

In recent years, grinding techniques for precision machining of brittle materials used in electric, optical and magnetic parts have been improved by using superabrasive wheel and precision grinding machine. The completion of optimum dressing of superabrasive wheel makes possible the effective precision grinding of brittle materials. However, the present dressing system cannot have control of optimum dressing of the superabrasive wheel. In this study, a new system and the grinding mechanism of optimum in-process electrolytic dressing were proposed. This system can carry out optimum in-process dressing of superabrasive wheel, and give very effective control according to unstable current and gap increase. Therefore, the optimum in-process electrolytic dressing is a good method to obtain the efficiency and mirror-like grinding of brittle materials.

• 대한기계학회논문집
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• 제18권3호
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• pp.785-792
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• 1994

Ferrite is widely used in the material of magnetic head, but is difficult of grinding because of their brittleness and hardness. Therefore, diamond wheel with superabrasive is required for surface grinding of this brittle material. But the conventional dressing method can not apply to the diamond wheel with superabrasive. In this study describes a newly proposed method for carrying out effective inprocess dressing of diamond wheel with superabrasive. Using the IEDD the surface roughness of workpiece was improved and grinding force was very low. Resently IEDD is good method to obtain the efficiency grinding and surface grinding of brittle materials.

• 한국공작기계학회논문집
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• 제12권3호
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• pp.1-7
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• 2003

In-process Electrolytic Dressing is a lapping method using electrolysis. This technology provides dressing to CIB-Diamond Lapping wheels during the lapping process for continuous protrude abrasive from super-abrasive wheels. so loading and glazing are disappeared apparently. Ultra-precision lapping of the machinable commies will be studied in the viewpoint of In-process Electrolytic Dressing. For ultra-precision lapping, need to develop an ultra-precision lapping system suitable metal bonded diamond wheel, and appropriate condition of u10a-precision lapping machining.

• 한국생산제조학회지
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• 제9권5호
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• pp.34-39
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• 2000

Application of ceramics has grown considerably due to significant improvement in their mechanical properties such as light weight, chemical stability and superior wear resistance. Despite these character, the use of ceramics has not increased because of poor machinability. The method of using of super-abrasives metal bond wheel was proposed. But it is difficult that super-abrasives metal bond wheel can be dressed. Recently, the technology of in-process electrolytic dressing is developed to solve this problem. If this method is applied, loading and glazing are disappeared apparently. The aim of this study is to determine the machining characteristics in terms of lapping wheel speed, machining time, pressurized weight to the workpiece and peak current using in-process electrolytic dressing applied to the CIB-diamond lapping wheel to achieve ultra-precision lapping machining technique.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.508-511
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• 2002

With increasing the needs for micro and precision parts, micro machining technology using micro tools has been studied to fabricate a small part with high density such as electronics, optics, communications, and medicine industry more than before. Though these micro tools have developed rapidly, it is difficult to apply them to micro fabrication technologies, because of the inherent manufacturing. In this study, micro tools(wc) to produce micro structures and parts were manufactured by cylindrical grinding machine employing ELID(Electrolytic In-process Dressing) technique and good dimensional accuracy was achieved. Furthermore we researched the characteristics of machining on the micro drilling using micro drills and manufactured micro tools. Finally it is confirmed that manufactured micro tools can be used for micro machining.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.914-917
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• 2000

Application of ceramics, carbide, ferrite has grown considerably due to significant improvement in their mechanical properties such as light weight, chemical stability , super wear resistance and electronical. Despite these character, the me of advanced material has not increased because of poor machinability. The method of using of metal bond wheel was proposed. But it is difficult that metal bond wheel can be dressed. Recently, the technology of in-process electrolytic dressing is developed to solve this problem. This method need wheel for electrolytic dressing, power supply and electrolyte. But development of wheel for electrolytic dressing is the most need. The aim of this study is development of wheel for electrolytic and appraisement of CIB-diamond lapping wheel

• 한국정밀공학회지
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• 제19권12호
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• pp.171-178
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• 2002

With increasing the needs for micro and precision parts, micro machining technology using micro tools has been studied to fabricate a small part with high density such as electronics, optics, communications, and medicine industry more than before. Though these micro tools have developed rapidly, it is difficult to apply them to micro fabrication technologies, because of the inherent manufacturing. In this study, micro tools (WC) to produce micro structures and parts were manufactured by cylindrical grinding machine employing ELID (Electrolytic In-process Dressing) technique and the micro tools are fabricated as square shape with the dimension less than 100${\mu}{\textrm}{m}$. With the micro tools on the same machine, characteristics of micro grooving and drilling are evaluated. Also we compare normal micro machining with ultrasonic micro machining on the vibration table. It is confirmed that the developed micro tools are fully applicable to micro grooving, micro drilling and free form cutting.