• Title/Summary/Keyword: Scan range

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Accuracy evaluation of treatment plan according to CT scan range in Head and Neck Tomotherapy (두경부 토모테라피 치료 시 CT scan range에 따른 치료계획의 정확성 평가)

  • Kwon, Dong Yeol;Kim, Jin Man;Chae, Moon Ki;Park, Tae Yang;Seo, Sung Gook;Kim, Jong Sik
    • The Journal of Korean Society for Radiation Therapy
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    • v.31 no.2
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    • pp.13-24
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    • 2019
  • Purpose: CT scan range is insufficient for various reasons in head and neck Tomotherapy®. To solve that problem, Re-CT simulation is good because CT scan range affects accurate dose calculations, but there are problems such as increased exposure dose, inconvenience, and a change in treatment schedule. We would like to evaluate the minimum CT scan range required by changing the plan setup parameter of the existing CT scan range. Materials and methods: CT Simulator(Discovery CT590 RT, GE, USA) and In House Head & Neck Phantom are used, CT image was acquired by increasing the image range from 0.25cm to 3.0cm at the end of the target. The target and normal organs were registered in the Head & Neck Phantom and the treatment plan was designed using ACCURAY Precision®. Prescription doses are Daily 2.2Gy, 27 Fxs, Total Dose 59.4Gy. Target is designed to 95%~107% of prescription dose and normal organ dose is designed according to SMC Protocol. Under the same treatment plan conditions, Treatment plans were designed by using five methods(Fixed-1cm, Fixed-2.5cm, Fixed-5cm, Dynamic-2.5cm Dynamic-5cm) and two pitches(0.43, 0.287). The accuracy of dose delivery for each treatment plan was analyzed by using EBT3 film and RIT(Complete Version 6.7, RIT, USA). Results: The accurate treatment plan that satisfying the prescribed dose of Target and the tolerance dose in normal organs(SMC Protocol) require scan range of at least 0.25cm for Fixed-1cm, 0.75cm for Fixed-2.5cm, 1cm for Dynamic-2.5cm, and 1.75cm for Fixed-5cm and Dynamic-5cm. As a result of AnalysisAnalysis by RIT. The accuracy of dose delivery was less than 3% error in the treatment plan that satisfied the SMC Protocol. Conclusion: In case of insufficient CT scan range in head and neck Tomotherapy®, It was possible to make an accurate treatment plan by adjusting the FW among the setup parameter. If the parameter recommended by this author is applied according to CT scan range and is decide whether to re-CT or not, the efficiency of the task and the exposure dose of the patient are reduced.

Practical theory and ocean survey application of side scan sonar (Side Scan Sonar 실무이론과 현장조사에 적용)

  • Kim, Seong-Ryul;Lee, Yong-Kuk;Jung, Baek-Hun
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.201-204
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    • 2006
  • In the side scan sonar method, use is made of the back-scattering, at low grazing angles of incidence to the seabed, of relatively high-frequency acoustic waves radiated in a fan-shaped beam from a transducer contained in a towed body. The fan beam is oriented so that the wider angle is in the vertical plane (scan range) and the narrower angle in the horizontal plane (beam width) with the axis of the beam normal to the ship track. The display of the returns is usually realized as a series of closely spaced intensity-modulated lines on a paper recorder or computer screen display. In this way a two-dimensional picture of the seabed is build up.

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New Protocol at Fast Scan Mode for Sea-surface Small Target Detection

  • Cha, Sangbin;Park, Sanghong;Jung, Jooho;Choi, Inoh
    • IEMEK Journal of Embedded Systems and Applications
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    • v.17 no.2
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    • pp.101-107
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    • 2022
  • In this article, we propose a new protocol at fast scan mode for a sea-surface small target detection. The conventional fast scan mode is composed of coherent intrascan integration to suppress sea clutter and non-coherent interscan integration to exclude sea spikes. The proposed method realizes the coherent interscan integration by the new Fourier relationship between carrier-frequency and initial-radial-range, which can be analytically derived by using multiple carrier frequencies at fast scan mode, leading to improved detection performance, compared to the conventional non-coherent methods. In simulations, our proposed method is verified.

The Study of Development by Intelligent Scan Laser Range Finder Supervisor System (지능형Scan Laser Range Finder 감시시스템 개발에 관한 연구)

  • Kim, Su-Kyum;Kim, Jong-Kyum
    • 한국IT서비스학회:학술대회논문집
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    • 2008.11a
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    • pp.411-414
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    • 2008
  • 해상사고로 인한 송전선로의 보호를 위해 Scan Laser Range Finder를 사용하여 해상에서의 일정한 높이에서 수평으로 레이저빔을 조사한 후 높이 기준을 넘는 선박을 검지하여 좌표와 속도를 측정하여 경보방송 및 무선 통신으로 회항을 유도하여 송전선을 감시 및 보호하는 기술개발로 산업 현장에서의 적응력을 높이는데 기여할수 있을것으로 보인다.

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Accuracy of bite registration according to the buccal bite scan range of intra-oral scanner (구강 스캐너의 협측 교합 스캔 부위에 따른 교합 인기의 정확도)

  • Tae-sung Kwon;Dae-hyun Kim;Min-su Kim;Dong-jun Song;Joo-Hun Song
    • Journal of Dental Rehabilitation and Applied Science
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    • v.40 no.3
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    • pp.125-134
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    • 2024
  • Purpose: The aim of this study was to determine which scan range would provide the most accurate bite registration when performing a bite scan after scanning an upper and lower arch using an intraoral scanner. Materials and Methods: The occlusal contact points were recorded using articulating paper for 30 adults, and the results of various ranges of buccal bite scan were compared based on this. Buccal bite scan of 5 ranges (1st premolar to 2nd premolar, 1st premolar to 1st molar, 1st premolar to 2nd molar, 2nd premolar to 1st molar, and canines to another side canine of the maxillary teeth) was performed, and then the buccal bite scan file was used in a CAD program to confirm the occlusal area in the scan file through data editing and alignment, leaving the buccal area of the teeth. Afterwards, the degree of agreement between the occlusal contact points obtained from the articulating paper and the occlusal area obtained from the scan file was compared, and statistical analysis was performed using the homoscedastic T-test (α = 0.05). Results: The alignment success and alignment failure rates among each group were 77.23% and 40.85% in canine to another side canine, 68.23% and 28.89% in bilateral first premolar to second premolar, 63.76% and 29.97% in bilateral first premolar to first molar, 61.31% and 32.04% in bilateral first premolar to second molar, 67.55% and 27.46% in second premolar to first molar. The results of the anterior scan of both canines showed higher alignment success and failure rates compared to the scan results of all maxillary posterior teeth. In the alignment success rate, statistical significance was not found depending on the scan range of the posterior teeth, but in comparing the results of the posterior teeth and both canines, statistical significance was observed except for the scan results of the second premolar to the first molar. There was no statistical significance in the alignment failure rate depending on the scan range of the posterior teeth, and statistical significance was observed in the results of the posterior teeth and both canines. Conclusion: When taking a buccal bite scan, in the case of scanning the anterior teeth, more occlusal area appear than when scanning the posterior teeth, and in the case of scanning the posterior teeth, there is no significant difference in the bite registration depending on the scan range.

Direction Augmented Probabilistic Scan Matching for Reliable Localization (신뢰성 높은 위치 인식을 위하여 방향을 고려한 확률적 스캔 매칭 기법)

  • Choi, Min-Yong;Choi, Jin-Woo;Chung, Wan-Kyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.12
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    • pp.1234-1239
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    • 2011
  • The scan matching is widely used in localization and mapping of mobile robots. This paper presents a probabilistic scan matching method. To improve the performance of the scan matching, a direction of data point is incorporated into the scan matching. The direction of data point is calculated using the line fitted by the neighborhood data. Owing to the incorporation, the performance of the matching was improved. The number of iterations in the scan matching decreased, and the tolerance against a high rotation between scans increased. Based on real data of a laser range finder, experiments verified the performance of the proposed direction augmented probabilistic scan matching algorithm.

Comparison on Track Formation Range between TWS and Adaptive Tracking Using Markov Chain Analysis in a Radar System (레이더에서의 Markov Chain 분석을 이용한 TWS 방식과 Adaptive Tracking 방식의 추적 형성 거리 비교)

  • Ahn, Chang-Soo;Roh, Ji-Eun;Jang, Sung-Hoon;Kim, Seon-Joo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.5
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    • pp.574-580
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    • 2013
  • Compared with the TWS(Track While Scan) tracking that uses scan-to-scan correlation at search illuminations for targets track, a phased array radar can use adaptive tracking which assigns additional track illuminations and the track formation range can be improved as a result. In this paper, an adaptive tracking, the search and track illuminations of a target are synchronized such that the extra illuminations are evenly distributed between the search illuminations, is proposed. Markov chain and track formation range for the proposed adaptive tracking are shown with them for the conventional TWS. The simulation result shows that the proposed adaptive tracking has improved track formation range by 27.6 % compared with the conventional TWS tracking under same track confirmation criterion.

HARDWARE DESIGN OF A SCAN CONVERTER USING SPLINE INTERPOLATION (스플라인 보간법을 적용한 스캔 변환기의 하드웨어 구현)

  • 권영민;이범근;정연모
    • Proceedings of the IEEK Conference
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    • 2000.11b
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    • pp.71-74
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    • 2000
  • The purpose of format conversion is to convert a wide range of personal computer video formats into a target format. Circuits for the conversion have been developed by means of interpolation techniques, such as zero-order interpolation, bilinear interpolation, and bisigmoidal interpolation. This paper proposes a scan converter using cubic splines. The converter was modeled in VHDL on Max+PlusII and implemented with an FPGA chip. The circuit gives much better conversion performance than a scan converter with zero-order or linear interpolation.

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A Scan Converter Using Spline Interpolation (스플라인 보간법을 이용한 스캔 변환기)

  • 이범근;권영민;정연모
    • Journal of the Korea Society for Simulation
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    • v.9 no.4
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    • pp.11-23
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    • 2000
  • The purpose of format conversion is to convert a wide range of personal computer video formats into a target format. Circuits for the conversion have been developed by means of interpolation techniques, such as zero-order interpolation, bilinear interpolation, and bisigmoidal interpolation. This paper proposes a scan converter using cubic splines. The converter was modeled in VHDL, simulated on Max+plus Ⅱ , and implemented with an FPGA chip. The circuit gives much better conversion performance than a scan converter with zero-order or linear interpolation techniques according to simulation results and implementation.

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