• 제목/요약/키워드: precision

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Precision Nanometrology and its Applications to Precision Nanosystems

  • Gao Wei
    • International Journal of Precision Engineering and Manufacturing
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    • 제6권4호
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    • pp.14-20
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    • 2005
  • In this paper, a new field of metrology called 'precision nanometrology' is presented. The 'precision nanometrology' is the result of evolutions of the traditional 'precision metrology' and the new 'nanometrology'. 'Precision nanometrology' is defined here as the science of dimensional measurement and motion measurement with 100 nm to 0.1 nm resolution/uncertainty within a range of micrometer to meter. The definition is based on the fact that nanometrology in nanoengineering and the precision industries, such as semiconductor industry, precision machine tool industry, precision instrument industry, is not only concerned with the measurement resolution and/or uncertainty but also the range of measurement. It should also be pointed out that most of the measurement objects in nanoengineering have dimensions larger than 1 micrometer. After explaining the definition of precision nanometrology, the paper provides several examples showing the critical roles of precision nanometrology in precision nanosystems, including nanometrology system, nanofabrication system, and nanomechatronics system.

정밀 위치 결정 및 고하중 부담 능력을 지닌 6-자유도 스테이지의 설계 (Design of a 6-DOF Stage for Precision Positioning and Large Force Generation)

  • 신현표
    • 한국정밀공학회지
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    • 제30권1호
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    • pp.105-112
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    • 2013
  • This paper presents the structural design and finite element analysis of precision stage based on a double triangular parallel mechanism for precision positioning and large force generation. Recently, with the acceleration of miniaturization in mobile appliances, the demand for precision aligning and bonding has been increasing. Such processes require both high precision and large force generation, which are difficult to obtain simultaneously. This study aimed at constructing a precision stage that has high precision, long stroke, and large force generation. Actuators were tactically placed and flexure hinges were carefully designed by optimization process to constitute a parallel mechanism with a double triangular configuration. The three actuators in the inner triangle function as an in-plane positioner, whereas the three actuators in the outer triangle as an out-of-plane positioner. Finite element analysis is performed to validate load carrying performances of the developed precision stage.

회절연산 정밀도에 따른 CGH 기반 홀로그램 생성 품질 분석 (Quality Analysis on Computer Generated Hologram Depending on the Precision on Diffraction Computation)

  • 이재홍;김덕수
    • 방송공학회논문지
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    • 제28권1호
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    • pp.21-30
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    • 2023
  • 컴퓨터 생성 홀로그래피는 일반 이미지에 비해 연산 부하와 메모리 요구량이 크다. 본 논문은 정밀도를 낮추어 연산속도를 높이는저정밀도(low-precision) 및 혼합정밀도(mixed precision) 연산 방법을 회절연산에 적용하여, 정밀도에 따른 홀로그램의 생성 속도와 품질의 변화를 분석한다. 본 논문은 배정밀도, 단정밀도, bfloat16 정밀도에서의 회전 연산을 비교하였으며, bfloat16의 회절연산의 속도가 배정밀도에 비해 최대 5.94배, 단정밀도에 비해 1.52배 빠른 것을 확인하였다. 또한, MSE, PSNR, SSIM을 기준으로 회절 연산의오차를 측정하였으며, 정밀도가 낮아질수록 홀로그램 품질이 낮아지는 것을 확인했다. 하지만, 정성적인 이미지 품질에는 유의미한 영향이 없는 것을 확인했다. 이러한 결과는, bfloat16등 낮은 정밀도 연산의 홀로그램 연산으로의 적용 가능성을 보여준다.

마찰력 측정을 통한 GMR 헤드 제작용 초정밀 연마판의 특성화 (Characterization of ultra Precision Grinding Plate for GMR Head Manufacturing by Measuring Frictional Force)

  • 노병국;김기대
    • 한국정밀공학회지
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    • 제20권7호
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    • pp.78-83
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    • 2003
  • Characterization of an ultra precision grinding plate for GMR head manufacturing is performed by measuring frictional forces between the grinding plate and the advanced ceramic Two kinds of methods of producing the precision grinding plates are presented: texturing and micro-channeling. Texturing is effective in terms of production time but micro-channeling excels in quality control. It is found that the frictional coefficient of a precision grinding plate decreases as the impregnation of diamond grain onto the precision-grinding plate progresses, and remains unchanged once the impregnation process is successfully completed, even after 100 revolutions of the precision-grinding plate against the advanced ceramic under 40 N of normal force. Therefore, the measurement of the frictional coefficient can replace costly and time-consuming process of estimating the level of impregnation of diamond grain on the precision-grinding plate, which has been performed by using scanning electron microscope, and be employed as an index to determine the level of impregnation of diamond grain.

He-Ne 레이저의 간섭을 이용한 고정밀 리니어 스케일의 제작에 관한 연구 (A Study on the Manufacturing of High Precision Linear Scale Using He-Ne Laser Interference)

  • 한응교;전병욱;이명호;박두원;노병옥
    • 한국정밀공학회지
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    • 제8권3호
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    • pp.82-92
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    • 1991
  • A study on the manufacturing of High Precision Linear Scalr using He-Ne Laser interference Of late, along with the advancement of precision machining technology, the requirement of super precision measurement increases as time goes on, and the accuracy of standard scale which is a basis of precision measurement has been cognized as a criterion of industrial development in a nationl. In this paper, we described on technology by which we could carve scale lines thru optical method under the condition of laboratory by using the coherence of He-Ne two-mode stabilized laser and in turn, put it to practical use as linear scale for the measurement of length. Hence in this research in the case of setting scale interval to 20 ${\mu}m$, we employed super precision scale-carving device associated with Ar laser and acousto optic modulator in lieu of flashing lamp scale-carving device, and we obtained as experimental result superior linear scales carved within the accuracy of ${\pm}$0.3${\mu}m$.

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단정도/배정도 승산을 위한 $200-MHz{\circled}a2.5-V$ 이중 모드 승산기 (A $200-MHz{\circled}a2.5-V$ Dual-Mode Multiplier for Single/Double-Precision Multiplications)

  • 이종남;박종화;신경욱
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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    • pp.149-152
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    • 2000
  • A dual-mode multiplier (DMM) that performs single- and double-precision multiplications has been designed. An algorithm for efficiently implementing double-precision multiplication with a single-precision multiplier was proposed, which is based on partitioning double-precision multiplication into four single-precision sub-multiplications and computing them with sequential accumulations. When compared with conventional double-precision multipliers, our approach reduces the hardware complexity by about one third resulting in small silicon area and low-power dissipation at the expense of increased latency and throughput cycles.

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공작기계 이송시 스틱슬립에 관한 고찰 (A Study of th stick-slip by feed of the machining center)

  • 정성택;박종남;조규재
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 추계학술대회 논문집
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    • pp.420-424
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    • 1997
  • n the ballscrew slide system the ~najor problems in accomplishing the high-speed and high-precision are the friction between elements and the decrease of axial stiffness. Especially the friction on the guide have a bad effect on the precision of slidlng. Furthermore stick-slip occur when the low stiffness of slide system. The sticli-slip have a bad influence on the precision. In this research, the affection of stick-slip friction to the precision of the slide system is studied and the possible solution of the precision is proixjsed.

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