• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.537-540
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• 2005

The attitude control, sensors and camera installed on the spacecraft should be located according to the system alignment requirement. The alignment measurement requirement accuracy for the sensors should be below $\pm$0.1. Therefore, Alignment Measurement System which is combined theodolite, Rotating table and digital inclinometer etc., should be used. As the measurement accuracy is required very precise, the appropriate measurement procedure and alignment angle measurement, calculation and shimming work should is accomplished. Consequently, this paper is accomplished the works to align the measurement requirement accuracy throughout alignment measurement and shimming work of installed module and sensor

• 한국공작기계학회논문집
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• 제12권6호
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• pp.64-70
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• 2003

A measurement of spacecraft alignment is an important process of spacecraft assembly, integration and test because it is necessary that a ground station controls the precise positions of on-orbit spacecraft by using the alignment data of attitude orbit control sensors(AOCS) on spacecraft. In addition, accuracy of spacecraft alignment requirement is about $0.1^{\circ}$~$0.7^{\circ}$. The spacecraft alignment is measured by autocollimation of theodolite. This paper describes the measurement principle and method of spacecraft alignment. The result shows that all of the AOCS on the spacecraft are aligned within the tolerance required through the alignment measurement.

• International Journal of Aeronautical and Space Sciences
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• 제2권1호
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• pp.44-54
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• 2001

This paper describes the antenna alignment method of the tracking antenna system for LEO satellite. The purpose of the antenna alignment is to reduce the angular error due to the structural alignment and the monopulse null point alignment error. The angular error of 3 axis tracking system is the key performance parameter that should be minimized to accurately track satellite movement. The angular error is analyzed via a simulation and boresight measurement. The simulation is done with formulas to be derived from vector concept for 3-axis movement. The formulas of the structural alignment are verified by comparing the formula result with the field measurement. Also, the angular error due to monopulse null shift is obtained via boresight measurement. Based on the analyzed and measured results, the antenna alignment was performed and was verified via tracking test of operating LEO satellite.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.263-264
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• 2009

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.537-538
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• 2009

• 한국항공우주학회지
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• 제31권10호
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• pp.105-111
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• 2003

위성체 정렬은 위성체 조립 및 시험과정에서 중요한 부분이다. 인공위성이 우주궤도상에서 성공적인 임무를 수행하기 위해서는 자세제어 및 탑재체용 부분품들에 대하여 측정허용오차 $0.1^{\circ}{\sim}0.7^{\circ}$의 정밀하고 정확한 측정이 요구되며 정렬된 상태에서의 위성체 좌표계의 정확한 방향좌표를 측정하여 지상에 위치한 위성체 관제부에서 위성체의 자세제어 등에 사용하도록 제공하게 된다. 본 논문에서는 자동시준에 의한 위성체 정렬 측정 이론에 대하여 기술하고 데오도라이트를 사용하여 위성체 정렬을 측정할 수 있는 측정방법 및 그 측정 결과에 대하여 고찰해 보고자 한다.

• 제어로봇시스템학회논문지
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• 제7권11호
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• pp.953-957
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• 2001

This paper is concerned with a transfer alignment method for the SDINS under ship motions. Major error sources of transfer alignment are data transfer time-delay, lever-arm velocity and ship body flexure. Specifically, to reduce alignment errors induced by measurement time-delay effects, the error compensation method through delay state augmentation is suggested. A linearized error model for the velocity and attitude matching transfer alignment system is first derived by linearizing the nonliner measurement equation with respect to its time delay and augmenting the delay state into the conventional linear state equations. And then it is shown via observability analysis and computer simulations that the delay state can be estimated and compensated during ship motions resulting in considerably less alignment errors.

• 한국공작기계학회논문집
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• 제18권1호
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• pp.83-89
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• 2009

In most multi-stage forging processes, the die spotting process or alignment of punch and die depends on the manual operation. It results a very tedious and inefficient procedure, thus the proper measurement system is needed to improve productivity and accuracy. This paper proposes a measurement system for alignment of die and punch which has a cylindrical holder, and describes the system concepts using 3 eddy-current displacement transducers and precise measurement jig. In order to apply this measurement system to real situations, the measuring procedures and system calibration method, etc. are proposed. Finally, the accuracy and productivity of this measurement system are investigated in this paper.

• 한국항공우주학회지
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• 제32권7호
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• pp.98-104
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• 2004

위성체 얼라인먼트 측정은 측정 정밀도가 ${\pm}0.5^{\circ}$ 이하로 매우 정밀한 것이다. 일반적으로 이러한 측정은 3대 이상의 데오드라이트를 사용하여 측정되고 있다. 그러나 위성체의 위치 안정성 등에 의해 측정 정밀도 오차가 발생될 수 있다. 이에 따라, 데오드라이트, 회전 테이블 및 전자식 수평계 등을 조합하여 새로운 얼라인먼트 측정 시스템을 개발하게 되었다. 본 논문에서 이러한 측정 시스템의 개념과 측정 방법을 기술하였고, 기존의 측정 방법보다 더 좋은 정밀도를 얻을 수 있음을 알 수 있다.

• The Journal of Korean Physical Therapy
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• 제16권2호
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• pp.17-21
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• 2004

We need to study about lower extremity alignment because the structure dictates the function of lower extremity. Through lower extremity alignment assessment in static posture, we recognize abnormal structural conditions which could affect dynamic motion such as gait. To evaluate of lower extremity alignment provide so many useful information, but method of measurement is so limited. Therefore, this review will assist understanding for measurement of lower extremity alignment in static posture. From now on study about the objective measurement method must be achieved much more in physical therapy.