• Title/Summary/Keyword: Alignment Measurement

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Improved X-ray Center Beam Alignment Evaluation Method (개선된 X선 중심선속정렬평가 측정법)

  • Choi, Seokyoon
    • Journal of the Korean Society of Radiology
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    • v.14 no.6
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    • pp.827-832
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    • 2020
  • X-ray equipment, which is frequently used in radiology and treatment, is the most common and most used equipment in clinical practice. Equipment must provide accurate information to patients through continuous quality control. In case of manual quality control measurement, reproducibility may be poor and there may be a problem with reliability of evaluation results. In this study, an automated program was developed and attempted to measure how much the central ray between the focus of the X-ray tube and the variable aperture of the diagnostic X-ray generator used in clinical practice coincides. As a result of the experiment, it succeeded in calculating the coordinates of the two center points, and the distance between the two points was calculated in pixels and applied to the judgment and the automatic judgment value for whether the center line coincidence is within the normal angle or the abnormal angle is presented. The results of this study are considered to be very helpful in the quality control of the X-ray apparatus.

A Leverage Strategy of the Defense Program Analysis Based on Systems Thinking (시스템 사고를 이용한 국방 사업분석 레버리지 전략)

  • Seo, Hyeok;Lee, Sang-Eun
    • Korean System Dynamics Review
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    • v.10 no.1
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    • pp.77-95
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    • 2009
  • The ever-increasing government budget constraints have led to a continued decline in the increase rate for defense spending, and the government's 5-year National Fiscal Management Plan has served to reinforce the verification and validation procedures for the Force Improvement Programs (FIP) budget requirements and performance. Additionally, as large programs are controlled in accordance with the Total Program Cost Management Guidelines, timely and credible feasibility study and performance measurement need to be conducted. Due to these internal and external circumstances, needs have surged for feasibility and economic effectiveness study for big ticket projects in the FIP sector, with an increasing number of studies conducted by external research institutes. However, questions have been raised regarding the credibility and thoroughness of the program analyses performed by these research institutes due to various restrictions. This paper analyzes and identifies the structural limitations and problems using a systems thinking approach, and examines the systemic characteristics of the program analysis system. It also presents policy intervention recommendations based on the theory of systems thinking, a method to regularize and reinforce the program analysis system. Policy interventions recommended to ensure alignment of the external studies to the clear analysis objectives and resolve the bottlenecks in the external analysis include training those in charge of external study commissioning for a short term intervention, and increasing the number of research institutes and consulting agencies utilizing analysis and evaluation experts who transition to the private sector from the military for a long term intervention. additionally presented are strategies and policy alternatives to best utilize these policy interventions. They will contribute to the stable funding of Force Improvement Programs and efficient utilization of defense budget.

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Development of An Automated Scanning Laser Doppler Vibrometer for Measurements of In-Plane Structural Vibration (평면 구조 진동 측정을 위한 자동화된 스캐닝 레이저 도플러 진동측정기의 개발 및 연구)

  • Kil, Hyun-Gwon
    • Journal of KSNVE
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    • v.7 no.2
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    • pp.231-238
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    • 1997
  • An automated scanning laser Doppler vibrometer (LDV) has been designed, and built to measure in-plane vibration fields over structures. Use of optical fibers allows the compact design of a laser probe head which can be scanned over the vibrating structures. An algorithm for automated self-alignment of the laser probe is developed. The system is completely automated for scanning over the structures, focusing two laser beams at each data point until the detected vibration signal is stable, and for recording and transferring the data to a system computer. The automated system allows one to get extensive data of the vibration field over the structures. The system is tested by scanning a piezoelectric cylindrical shell and a plate excited by a continuous signal and by a pulse signal, respectively. Results show that the automated scanning LDV system can be a useful tool to measure the in-plane vibration field and to detect the elastic waves propagating on the vibrating structures.

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Progressive Residual Motion Estimation for Constructing Seamless Mosaics (이음매없는 모자이크 구성을 위한 단계적 잔여 움직임 추정)

  • Lee Cheong Woo;Choi Jae Gark;Lee Si-Woong
    • Journal of KIISE:Software and Applications
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    • v.32 no.6
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    • pp.512-522
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    • 2005
  • In this paper an algorithm of image alignments for constructing seamless mosaics is proposed. After the global alignment has been run, there may still be localized mis-registrations present in the mosaic. Due to mis-registrations, there may be seams in the mosaic, such as breaking, blurring, and doubling of lines. To solve this problem, we need an algorithm of residual motion estimation, which minimizes mis-registrations. In the conventional algorithms of residual motion estimation, computational powers are too heavy and estimators of camera parameters are additionally needed such as focal lengths. In the proposed algorithm, residual motion vectors are estimated with the adequate size of estimation and measurement windows and with adjustment of initial vectors according to the established priority. By construction of mosaics with the proposed algorithm, we demonstrate the removal of seams by mis-registrations.

Aircraft Deformation Measurement using Industrial Photogrammetry (산업사진측량기법을 이용한 항공기 변형 측정)

  • Lee Jae-Kee;Jung Sung-Heuk;Yu Jung-Hum
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.23 no.2
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    • pp.205-210
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    • 2005
  • As industries developed, industrial goods have got more precise. It led producers to feel like having a way to confirm whether the goods are good enough for the needs of consumers or not. Because of that, producers got interested in industrial photogrammetry that can get accurate data quickly with non-confect method. therefore, this study was examined by photographing an O-2A aircraft which was a large and precise one to check the application of Industrial photogrammetry. To measure the aircraft, the check points, that was attached to it was used as it was not possible to measure the aircraft by its design. The experiment was carried out in three parts considering arrangement of the check points and measured with Pro-spot to check any deformation of its external form. As a result, this study enables us to conferm a state of the aircraft alignment promptly and to provide accurate data for producers, which helps them to make a decision.

Morphometric Variations in the Volar Aspect of the Distal Radius

  • Kwon, Bong Cheol;Lee, Joon Kyu;Lee, Suk Yoon;Hwang, Jae Yeun;Seo, Jang-Hyeon
    • Clinics in Orthopedic Surgery
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    • v.10 no.4
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    • pp.462-467
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    • 2018
  • Background: Significant discrepancy exists between anatomical plate designs and the anatomy of the native distal radius, which may be attributable to considerable morphometric variations in the volar aspect of the distal radius. We aimed to evaluate the degree of variability in the morphometry of the distal radius and identify factors associated with this variability. Methods: We measured the volar surface angle (VSA) of the intermediate and lateral columns and the volar surface width (VSW) in the distal radius from three-dimensional computed tomography scans acquired from 81 cadaveric forearms. These morphometric parameters were compared between the lateral and intermediate columns, between males and females, and between Koreans and Caucasians. Caucasian morphometric data were obtained and pooled from the previous studies. The coefficient of variation was used to assess the variability of the parameters and Cohen's d to estimate the effect size of the difference between groups. Results: The average VSA of the lateral column was $22^{\circ}{\pm}6^{\circ}$, and that of the intermediate column was $29^{\circ}{\pm}8^{\circ}$ in Koreans (p < 0.001). The variability was high for both VSAs. The VSA of the intermediate column was significantly larger in males than in females (p < 0.001) and in Caucasians than in Koreans (p < 0.001). The average VSW of distal radius was $30{\pm}3mm$ at the watershed line, and it became narrower proximally. The VSW was significantly larger in males than in females (p < 0.001) and in Koreans than in Caucasians (p < 0.001). The effect sizes of the difference for the VSA and VSW between sexes, races and columns were medium to large. Conclusions: Considerable variability exists in the morphometry of the volar distal radius, with sex, race, and column as contributing factors. These results suggest that surgeons should carefully choose an anatomical volar locking plate with appropriate angulation characteristics for each patient to achieve patient-specific alignment of the distal radius.

The Standard Processing of a Time Series of Imaging Spectral Data Taken by the Fast Imaging Solar Spectrograph on the Goode Solar Telescope

  • Chae, Jongchul;Kang, Juhyeong;Cho, Kyuhyoun
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.2
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    • pp.46.1-46.1
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    • 2018
  • The Fast Imaging Solar Spectrograph (FISS) on the Goode Solar Telescope (GST) at Big Bear Solar Observatory is the imaging Echelle spectrograph developed by the Solar Astronomy Group of Seoul National University and the Solar and Space Weather Group of Korea Astronomy and Space Science Institute. The instrument takes spectral data from a region on the Sun in two spectral bands simultaneously. The imaging is done by the organization of intensity data obtained from the fast raster scan of the slit over the field of view. Since the scan repeats many times, the whole set of data can be used to construct the movies of monochromatic intensity at arbitrary wavelengths within the spectral bands, and those of line-of-sight velocity inferred from different spectral lines. So far there are two standard observing configurations: one recording the $H{\alpha}$ line and the Ca II 8542 line simultaneously, and the other recording the Na I D2 line and Fe I 5435 line simultaneously. We have developed the procedures to produce the standard data for each observing configuration. The procedures include the spatial alignment, the correction of spectral shift of instrumental origin, and the lambdameter measurement of the line wavelength. The standard data include the movie of continuum intensity, the movies of intensity and velocity inferred from a chromospheric spectral line, the movies of intensity and velocity inferred from a photospheric line. The processed standard data will be freely available online (fiss.snu.ac.kr) to be used for research and public outreach. Moreover, the IDL procedures will be provided on request as well so that each researcher can adapt the programs for their own research.

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Comparison of the Thickness of the Neck Flexor Between Open and Closed Kinetic Chain Exercises During Chin-in Movement (슬링을 이용한 열린사슬운동과 닫힌 사슬 운동의 턱당기기 동작 시 목굽힘근 두께 비교)

  • Lee, Ju-Hun;Han, Jin-Tae
    • PNF and Movement
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    • v.18 no.3
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    • pp.333-341
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    • 2020
  • Purpose: The purpose of this study was to investigate the effect of open and closed kinetic chain exercises with a sling on neck flexor thickness during chin-in movement in office workers with forward head posture. Methods: Thirty-one selected subjects randomly performed chin-in movement in open kinetic chain and closed kinetic chain exercises using a sling. All subjects were measured for their neck flexor thickness using ultrasound measurement equipment during the performance of chin-in movement in open and closed kinetic chain exercised. A paired t-test was used to compare the thickness of the total neck flexor, superficial, and deep neck flexor, respectively, between open and closed kinetic chain exercises with chin-in movement. Results: The thickness of the superficial neck flexor diminished in size more greatly during the chin-in movement with the closed kinetic chain than the open kinetic chain, but this was not a statistically significant difference (p > 0.05). On the other hand, the thickness of the total neck flexor and deep neck flexor had more greatly increased during the chin-in movement with the closed kinetic chain than the open kinetic chain, and this was a statistically significant differences (p < 0.05). Conclusion: This study suggested that chin-in movement with a closed kinetic chain is more effective in activating the deep neck flexor than the open kinetic chain. Thus, we believe that the closed kinetic chain exercise using a sling is an effective intervention to correct the postural alignment of individuals with forward head posture.

Radiographic Comparison of Cranial Tibial Wedge Osteotomy versus Tibial Plateau Leveling Osteotomy: A Cadaveric Study

  • Lee, Jiyoon;Kim, Dongwook;Oh, Hyejong;Lee, Sungin;Choi, Seok Hwa;Kim, Gonhyung
    • Journal of Veterinary Clinics
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    • v.39 no.3
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    • pp.93-99
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    • 2022
  • The present study was performed to compare cranial tibial wedge osteotomy (CTWO) and tibial plateau leveling osteotomy (TPLO) through radiographic evaluation. The experiment was conducted with five cadaver dogs [mean (± SD) weight, 32.9 ± 4.1 kg; mean (± SD) age, 6 ± 2 years; three males and two females] euthanized for reasons unrelated to this study. The cadaver dogs consisted of German Shepherd (n = 3), Belgian Malinois (n = 1), and mixed breed (n = 1). CTWO and TPLO were carried out by the standard surgical method. Radiographic evaluation was performed by comparing several factors, including the flexion and extension angles, the anatomical mechanical axis angle (AMA-angle), tibial length, patellar height measurement using the Labelle-Laurin method, mechanical medial proximal tibial angle (mMPTA), mechanical medial distal tibial angle (mMDTA), and frontal plane alignment (FPA). Both the CTWO and the TPLO groups showed significantly increased flexion angles after surgery. Only the CTWO group had significantly increased extension angle. Although both groups showed significant decreases in the AMA-angle, the mechanical axis moved cranially against the anatomical axis only in the CTWO group. The patellar height was significantly lowered in the CTWO group. No significant differences were found in mMPTA, mMDTA, or FPA. In conclusion, radiographic comparison revealed more changes in CTWO group than in TPLO group.

Effects of Neck and Pelvic Exercise Using Swiss Ball on Spinal Curve in Adults with Forward Head Posture (전방머리자세 대상자에 대한 목운동과 골반운동이 척추 굽이에 미치는 효과)

  • Bae, Won-Sik;Jang, Chel
    • Journal of The Korean Society of Integrative Medicine
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    • v.9 no.3
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    • pp.193-201
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    • 2021
  • Purpose : The purpose of this study was to compare the effect of pelvic exercise on the CVA and spinal curve in adults with forward head posture compared to the group using only neck exercise when pelvic exercise was performed in parallel with conventional neck exercise. Methods : GPS 400 and Formetric were used to identify craniovertebral angle (CVA), thoracic kyphosis, lumbar lordosis, and pelvic torsion and were measured by an experienced research manager. Forward head posture (FHP) was selected for people whose angle between the line connecting the ear ball and the seventh cervical spine and the horizontal line is 50 degrees or less. The 30 selected students were randomly divided into 15 experimental groups and 15 control groups. Mackenzie exercise and sling exercise were performed for neck exercise in both the experimental group and the control group, and pelvic exercise using a Swiss ball was additionally performed in the experimental group. All data collected in this study were analyzed using SPSS statistics 21.0. Cervical vetebral angle (CVA), thoracic kyphosis, lumbar lordosis, and pelvic torsion were compared at 0 weeks, 3 weeks, and 6 weeks for each measurement factor using ANOVA with repeated measures. For the statistical significance test, the significance level of α was set to .05. Results : The changes of pelvic torsion, thoracic kyphosis and CVA due to pelvic exercise using Swiss Ball and neck exercise were changed over time, but lumbar lordosis were not changed. And there were no significant differences among the groups. Conclusion : In conclusion, the pelvic correction exercise is considered to be an effective exercise for correcting the FHP and requires regular pelvic correction exercises. We expect the results to be used in clinical trials.