• 제목/요약/키워드: Measurement Table

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A Study on Alignment Measurement and Compensation for Spacecraft Sensors (위성 탑재 센서의 정렬 측정 및 보정에 관한 연구)

  • Lee Byoung-Gi;Kim Young-Youn;Yoon Yong-Sik
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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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

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A Study on the Occurrence Character of Contaminant in the Kitchen that Use Gas Fuel (가스를 연료로 사용한 주방에서의 오염물질 발생 특성에 대한 연구)

  • 박명길;함진식
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2001.11a
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    • pp.77-82
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    • 2001
  • This paper is contents that measure the ventilation rates and temperature by driving condition of exhaust fan, vapor, contaminant occurrence amount of carbon dioxide etc. In kitchen of apartment house. The ventilation rates in the apartment kitchen measured by Tracer Gas Method. And, temperature of when cook by gas table hood lower part 10cm and floor upside 10cm of kitchen central part, 120cm, 210cm heights measure. As ventilation rates measurement result, ventilation number of times was 0.7(number of times/hour) when did not to operate exhaust fan. but we were measured by 2.3(number of times/hour) when drove strongly. As temperature measurement result at cooking by gas table, temperature showed highest in hood lower part 10cm of case that do not operate exhaust fan. Temperature at kitchen central was most low in 10cm height in talc floor, and 210cm were measured highest. Concentration of carbon dioxide is very high by 4,350ppm after measurement time 10 minutes in state who do not operate exhaust fan at cooking by gas table.

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Selecting Common Items for Linking the Oswestry Low Back Pain Questionnaire and a Short Form of Self-Reported Activity Measure for Low Back Pain

  • Choi, Bong-sam
    • Physical Therapy Korea
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    • v.22 no.3
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    • pp.61-70
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    • 2015
  • To develop an effective and efficient measurement system for tracking changes of functional status across two measures, it is essential to integrate information and communicate scores across two measures. The lack of communication between two measures leads to score incompatibility. A potential solution would be the development of a crosswalk table between those measures. Prior to creating a crosswalk table, selecting common items between two measures is critical. By using the Oswestry low back pain disability questionnaire (Oswestry) and a short form measuring disability resulting from low back pain, item level statistics as well as differential item functioning (DIF) using the Rasch measurement were investigated. Eighty-two participants with known group validity were recruited. Based on the application of the Rasch measurement model, item difficulties across the two measures were logically and hierarchically ordered. Ceiling effects for both measures were detected, which were not be able to be effectively measured with the two measures. The DIF analysis across the two measures confirmed that five paired items were found to have DIF and five common items were selected for common items. Although five paired items function differently across the Oswestry and the short form, all items of both measures were well targeted study participants. The common items selected by the Rasch measurement model may be effective when creating a crosswalk table between the Oswestry and the short form.

ML-6M선형 가속기에서의 BEAM 특성에 대한 고찰

  • Mun, Eon-Cheol;Yun, Byeong-Un;O, Yang-Hwan
    • The Journal of Korean Society for Radiation Therapy
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    • v.5 no.1
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    • pp.115-119
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    • 1992
  • The beam characteristics and dosimetric measurements of the 6MV X-ray and 6MeV electron beam from a ML-6M linear accelerator are examined. The Percent Depth Dose(PDD) table and the tissue Maximum Ratio(TMR) table are taken from measurement as a function of the field size and the depth. The calculated TMR table from PDD table is compared with those from measurement. Other beam characteristics such as output factor, beam profile(including flatness, symmetry and penumbra), wedge, and the variation of Dmax are presented. All of these dosimetric measurements sufficiently characterized the beam to permit safe clinical use.

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Charateristics of 10MV X-ray Beam from a Mevatron KD Linear Accelerator (Mevatron KD 선형 가속기에서의 10MV X-선 특성)

  • Yi, Byong-Yong;Lee, Myung-Za
    • Radiation Oncology Journal
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    • v.6 no.1
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    • pp.101-108
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    • 1988
  • The beam characteristics and dosimetric measurements of the 10MV X-ray beam from a Mevatron KD linear accelerator are examined. The Percent Depth Dose (POD) table and the Tissue Maximum Ratio (TMR) table are taken from measurement as a function of the field size and the depth. The calculated TMR table from PDD table is compared with those from measurement. Other beam characteristics such as output factor, beam profile (including flatness, symmetry and penumbra), wedge, and the variation of Dmax are presented.

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Design and Constrvction of a Granite Optical Table with a Vibration Isolator (진동 방지기를 갖는 화강암 광탁자의 설계 및 제작)

  • Song, Jae--Won;Yu, Sang-Dae
    • Proceedings of the KIEE Conference
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    • 1987.07a
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    • pp.98-100
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    • 1987
  • A granite optical table with a vibration isolator system is designed and constrvcted. The table top is made with granite and the vibration isolation system is constrvcted using a pneumatic isolator. The performance of the table is evalvated by the vibration measurement.

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A Study on Radiation Dose and Image Quality according to CT Table Height in Brain CT (두부 CT 검사 시 테이블 높이에 따른 선량과 화질에 관한 연구)

  • Ki-Won Kim;Joo-Young Oh;Jung-Whan Min;Sang-Sun Lee;Young-Bong Lee;Kyung-Hwan Lim;Yun Yi
    • Journal of radiological science and technology
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    • v.46 no.2
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    • pp.99-106
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    • 2023
  • The height of the table should be considered important during computed tomography (CT) examination, but according to previous studies, not all radiology technologists set the table at the patient's center at the examination, which affects the exposure dose and image quality received by the patient. Therefore, this study intends to study the image quality exposure dose according to the height of the table to realize the optimal image quality and dose during the brain CT scan. The head phantom images were acquired using Philips Brilliance iCT 256. When the image was acquired, the table height was adjusted to 815, 865, 915, 965, 1015, and 1030 mm, respectively, and each scan was performed 3 times for each height. For the exposure dose measurement, optically stimulated luminescence dosimeter (OSLD) was attached to the front, side, eye, and thyroid gland of the head phantom. In the signal to noise ratio (SNR) measurement result, The SNR values for each table height were all lower than 915 mm. As a result of exposure dose, the exposure dose on each area increased as the table height decreased. The height of the table has a close relationship with the patient's radiation exposure dose in the CT scan.

A study on the measurement of rotary table error with 5-axis CNC machine (5축CNC공작기계의 회전테이블 오차 측정에 관한 연구)

  • SUH, S.H.;JUNG, S.Y.;LEE, E.S.
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.11
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    • pp.84-92
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    • 1997
  • The purpose of this study is to develop a geometric error model and path compensation algorithm for rotating axes of the 5-axis machine tools, by a method to calibrate a rotary table using one master ball and three LVDTs. It was developed a new methodology to measure 3 translation errors of the rotary table and with a compensation procedure for setup errors of the master ball. The method is experimentally verified using a ball-table and on-machine inspection method. The results showed that the geometric error models with the path compensation strategy can be practically used as a means for improving the accuracy of the machine tools with rotary table.

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Study on the Observability of a Calibration System for a Parallel Tilting Table with Measuerment Operator (측정연산자에 의한 병렬기구 틸팅 테이블의 관측성에 관한 연구)

  • Park Kun Woo;Lee Min Ki;Kim Tae Sung
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.6 s.237
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    • pp.795-803
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    • 2005
  • This paper studies the observability of calibration system with a measurement operator. The calibration system needs a simple digital indicator to measure the mobile table movements with respect to the MC coordinate. However, it yields the concern about the poor parameter observability due to measuring only a part of the movements. We uses the QR-decomposition to find the optimal calibration configurations maximizing the linear independence of rows of an observation matrix. The number of identifiable parameter is examined by the rank of the observation matrix, which represents the parameter observability. The method is applied to a 6-axis MC with parallel tilting table and the calibration results are presented. These results verify that all necessary kinematic parameters are observable and the calibration system has robustness to the noise using optimal calibration configurations.

A Study on A Spacecraft Alignment Measurement System (위성체 얼라인먼트 측정 시스템에 관한 연구)

  • Park, Hong-Chul;Son, Young-Seon;Choi, Jong-Yeon;Yoon, Yong-Sik
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.7
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    • pp.98-104
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    • 2004
  • A spacecraft alignment measurement requires highly precise measurement accuracy which is less than ${\pm}0.5^{\circ}$. In general, such an alignment measurement has been performed by using three or more theodolites. However, it contains the latent accuracy error because of a position stability of spacecraft, etc. The new alignment measurement system which consists of a theodoilte, a rotating table and a digital inclinometer has been developed to possibly to possibly reduce the error. This paper describes the concept and methodology of methodology of measurement system. It was found that new measurement system can provide more accurate results than the conventional system.