• Title/Summary/Keyword: deviation correction

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A Study on the Correction Method for Deviations and Variations of Digital Magnetic Compass (디지털 자기 컴퍼스의 자차와 편차 수정에 관한 연구)

  • Yim, Jeong-Bin;Saha, Rampadha
    • Proceedings of KOSOMES biannual meeting
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    • 2006.11a
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    • pp.137-141
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    • 2006
  • To consider the practical use of a ship's Digital Compass in earth's magnetic field high accurate Deviation and 얘 nation are required to obtain ship's true bearing. Variation can be obtain with World Magnetic Model (WMM) using the Earth's spherical harmonic model of the main field and of the secular variation at any location around the earth. Deviation can be obtain with deviation analysis and synthesis method based on the Poisson equations. As results of deviation and variation corrections to the Digital Compass, high accurate true bearing is obtained. This experiments are carried out during in the navigation of training ship 'SAE-NU-RI'.

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A Study on Sensor Collection Planning based on Target Scheduling and Deviation Correction for Strategic UAV Surveillance and Reconnaissance (전략급 무인기의 감시정찰을 위한 표적 스케줄링 및 편차 보정 기반 촬영계획 자동화 기술 연구)

  • Junghee Cho;Yunjeong Choi;Hayrim Lee;Soyoung Jeong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.27 no.2
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    • pp.177-188
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    • 2024
  • The strategic UAV for theater level ISR(Intelligence, Surveillance and Reconnaissance) mission typically has numerous ground targets over area of responsibility(AOR) or area of operation(AO). It is necessary to automatically incorporate these multitude of ground targets into mission planning process in order to collect ISR images before actual flight mission. In addition, weather information such as wind direction and/or velocity may have significant impacts on the qualities of collected sensor images, especially in SAR(Synthetic Aperture Radar) images. Thus weather factors in the operation altitude should also be considered in the mission planning stage. In this study, we propose a novel mission planning scheme based on target scheduling and deviation correction method incorporating weather factors.

Correction of Fluoroscopic Image for Nucleoplasty in Lumbar Disc (요추디스크 수핵감압술을 위한 투시영상의 교정)

  • Yun, Young Woo;Kang, Se Sik;Choi, Seok Yoon
    • Journal of the Korean Society of Radiology
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    • v.10 no.5
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    • pp.359-365
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    • 2016
  • Fluoroscopy is performed when tissue or organ in the human body is examined, and it is used for diagnosis and procedure in back ailments. With regard to fluoroscopy equipment, distortion occurs on the peripheral part of fluoroscopic image rather than on its central part. This study measured distortion factors of vertical spacing ratio and distortion factor of diagonal spacing ratio before and after correction by applying a correction algorithm. According to measuring the vertical spacing ratio, post-correction standard deviation decreased by 0.04 in comparison with pre-correction one. Also measuring the diagonal spacing ratio, post-correction standard deviation decreased by 0.06 in comparison with pre-correction one. Consequently, the distortion of fluoroscopic image decreased after correction. A decrease in the distortion of image through the application of correction algorithm and the improvement of performance will be helpful in finding a correct position of lumbar puncture in nucleoplasty to treat lumbar disc herniation in the future.

Study on the Integration of MMS and Airborn Survey Data for the Implementation of Precise Road Spatial Database (정밀도로공간정보 구축을 위한 지상 MMS 측정자료와 항공측량자료의 결합방법 연구)

  • Hwang, Jin Sang;Kim, Jae Koo;Yun, Hong Sik;Jung, Woon Chul
    • Journal of Korean Society for Geospatial Information Science
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    • v.23 no.2
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    • pp.97-104
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    • 2015
  • Due to the introduction of various IT devices, including the recently smartphones and the widespread use of the car navigation system to the location-based information service space has been increased. Spatial information users have been requiring higher levels of quality. In this paper, we study how to build accurate three-dimensional space information by integrating MMS(Moblie Mapping System) survey and airborne survey data. Thus, to analyze the tendency of deviation between the MMS survey and airborne survey data observed in the experimental region, the deviation tendency of the data, it was confirmed that was not consistent. Deviation correction model to select how to change the georeferencing information directly contained in the GPS/INS processing results for the determination, classifies the standard is a method for acquiring the correction reference point coordinates using the calibration model, and analyzed their advantages and disadvantages. With the information of the reference point obtained by airborne photograph of a project, using the method of correcting the MMS survey data. Not only clear the deviation existing between the MMS survey data, it was possible to confirm that the deviation exists between the airborne survey data and MMS survey data was also almost erased.

A STUDY OF THE DEVIATION-MEASURING METHOD & AUTOMATIC DEVIATION-CORRECTING APPARATUS (자차측정 방법 및 자동 자차수정 장치에 대한 연구)

  • Park, Hyuk;Park, Jin-woo;Kim, Boo-il
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.181-184
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    • 2016
  • This study is to compensate for inaccuracies in accordance with the change in the deviation correction value due to the movement and location of the ship cargo, equipment of the vessel, and eliminating the inconvenience of hand. By modifying the deviation through the simplification and automation was planned for accuracy and ease of modification of the modified value. The main method used is charted by measuring 24 direction and inputting the value of magnetic compass direction in automatic deviation-correcting apparatus manually or automaticallyThe measured values are exhibited in Table data and made it possible to calculate accurate correction value deviation. From this it can make deviation table having the margin of error within ${\pm}3^{\circ}$in all regions of the world And this table will help to navigational safety and economy under the unavailable or limited gyro contion.

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Establishment of Correction Equation for Filling Volumn according to Moisture Content (수분 함량별 부풀성 보정식 설정)

  • Chung Han-Joo;Kim Yong-Ok
    • Journal of the Korean Society of Tobacco Science
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    • v.27 no.1 s.53
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    • pp.94-99
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    • 2005
  • To correct the difference of filling volumn for various cut tobacco and puffed stem according to moisture contents, correction equation was estamated by a simple regression analysis. The $R^2$(coefficient of determination) of correction equation was above 0.95. To verify the precision of correction equation, we predicted correction equation of other samples. The filling volumns by the difference of $1\%$ moisture content were $0.018\;~\;0.022cc/g$ (cut tobacco) and 0.060cc/g (puffed stem). The precision of correction equation for various cut tobacco was very high, but that of puffed stem was low due to quality deviation of row stem according to a season.

Transmission Performance Improvement Using Brightness Deviation for Visual-MIMO System (Visual-MIMO 시스템에서 휘도편차를 이용한 전송 성능 향상)

  • Kim, Hee-jin;Kwon, Tae-ho;Park, Young-il;Kim, Ki-doo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.10
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    • pp.1871-1878
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    • 2015
  • Recently, research on the Visual-MIMO by applying the concept of MIMO to communication between the LED array and camera is in progress. Although we already introduced the method for bit decision by using reference LED array pattern, it has the disadvantage of measuring the ISI each time when there is a change in the distance. To overcome this, in this paper, we propose a bit decision and error correction method used by using the luminance deviation without using the reference array pattern. First, we execute the bit decision using experimentally determined threshold. Next, we execute the error checking on the ON-LED and make a correction only if it is found to be error. Correction is determined by using the value of brightness deviation corresponding to the range of 68.2% (1) around the maximum frequency of the histogram for each ON-LED. We verify the performance of the proposed method according to the variation of ISI with distance by using both numerical and experimental analysis.

CHANGE OF LIP CANTING AFTER BIMAXILLARY ORTHOGNATHIC SURGERY (상하악 악교정수술 후 입술 기울기변화)

  • Lee, Jun-Hee;Hong, Jong-Rak;Kim, Young-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.6
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    • pp.643-647
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    • 2007
  • Purpose: The purpose of study was to investigate the correlationship between lip canting change and occlusal canting change after bimaxillary orthognathic surgery, and the ratio of lip canting change and occlusal canting change after the surgery. Patients and methods: The subjects for this study was obtained from a group of 25 patients who took bimaxillary orthognathic surgery for occlusal canting correction at the Department of the Oral and Maxillofacial Surgery, Samsung Medical Center in Seoul, Korea between January 2000 and December 2005 and a patient's chart had to contain a resting frontal facial photograph in natural head position and a corresponding PA cephalogram in occlusion on the same day before the surgery and post-op 6 months later. The lip canting change was assessed with the angle each labial commissure and the bipupilary reference line. And, the occlusal caning change in the frontal plane was assessed with the angle between the each maxillary first molar occulasal surface and the bi-frontozygomatic suture reference line. Results: In angular measurement, average occlusal canting change was $3.09^{\circ}$ and standard deviation was $1.05^{\circ}$, average lip canting change was $1.56^{\circ}$ and standard deviation was $1.05^{\circ}$. In linear measurement, average occlusal canting change was 2.41mm and standard deviation was 2.75mm, average lip canting change was 1.18mm and standard deviation was 0.43mm. Lip canting correction ration to occlusal canting correction was 51.5(${\pm}8.4$)% in angular measurement and 48.8(${\pm}9.1$)% in linear measurement. Under Pearson's correlation analysis, Pearson's correlation coefficient was 0.869 in angular measurement and 0.887 in linear measurement(p-value < 0.01). High correlationship was shown between occlusal canting change and lip canting change. Conclusion: First, Bimaxillary orthognathic surgery can correct lip canting as well as occlusal canting. Second, The average amount of lip canting correction is $51.5{\pm}8.4%,\;48.8{\pm}9.1%$ of occlusal canting correction in the study.

Common Sites, Etiology, and Solutions of Persistent Septal Deviation in Revision Septoplasty

  • Jin, Hong Ryul;Kim, Dae Woo;Jung, Hahn Jin
    • Clinical and Experimental Otorhinolaryngology
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    • v.11 no.4
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    • pp.288-292
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    • 2018
  • Objectives. To investigate the common causes of persistent septal deviation in revision septoplasty and to report the surgical techniques and results to correct them. Methods. A total of 100 consecutive patients (86 males) who had revision septoplasty due to persistent septal deviation from 2008 and 2014 were included in the study. Their mean age was 35.6 years and the mean follow-up duration was 9.1 months. Presenting symptoms, sites of persistent septal deviation, techniques used to correct the deviation, and surgical results were reviewed. Results. The mean interval between primary and revision surgery was 6.2 years. Forty-eight patients received revision septoplasty and 52 received revision septoplasty combined with rhinoplasty. Nasal obstruction was the most presenting symptom in almost all patients. The most common site of persistent septal deviation was middle septum (58%) followed by caudal septum (31%). Correcting techniques included further chondrotomy and excision of deviated portion in 76% and caudal batten graft in 39%. Rhinoscopic and endoscopic exams showed straight septum in 97% and 92 patients had subjective symptom improvement postoperatively. Conclusion. Middle septum and caudal septum were common sites of persistent deviation. Proper chondrotomy with excision of deviated middle septum and correction of the caudal deviation with batten graft are key maneuvers to treat persistent deviation.

Calibration Technology for Precise Alignment of Large Flat Panel Displays (대형 평판 디스플레이의 정밀 정렬을 위한 캘리브레이션 기술)

  • Hong, Jun-Ho;Shin, Dongwon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.21 no.3
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    • pp.100-109
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    • 2022
  • In this study, calibration technology that increases the alignment accuracy in large flexible flat panels was studied. For precise of calibration, a systematization of the calibration algorithm was established, and a calibration correction technique was studied to revise calibration errors. A coordinate systems of camera and UVW stage was established to get the global position of the mark, and equations for translational and rotational calibration were systematically derived based on geometrical analysis. Correction process for the calibration data was carried, and alignment experiments were performed sequentially in cases of the presence or absence of calibration-correction. Alignment results of both calibration correction and non-calibration correction showed accuracy performance less than 1㎛. On the other hand, the standard deviation in calibration-correction is smaller than non-calibration correction. Therefore, calibration correction showed improvement of the alignment repeatability.