• Title, Summary, Keyword: target motion analysis

Search Result 217, Processing Time 0.051 seconds

Dosimetric Analysis on the Effect of Target Motion in the Delivery of Conventional IMRT, RapidArc and Tomotherapy

  • Song, Ju-Young
    • Progress in Medical Physics
    • /
    • v.28 no.4
    • /
    • pp.164-170
    • /
    • 2017
  • One of the methods to consider the effect of respiratory motion of a tumor target in radiotherapy is to establish a treatment plan with the internal target volume (ITV) created based on an accurate analysis of the target motion displacement. When this method is applied to intensity modulated radiotherapy (IMRT), it is expected to yield a different treatment dose distribution under the motion condition according to the IMRT method. In this study, we prepared ITV-based IMRT plans with conventional IMRT using fixed gantry angle beams, RapidArc using volumetric modulated arc therapy, and tomotherapy using helical therapy. Then, the variation in dose distribution caused by the target motion was analyzed by the dose measurement in the actual motion condition. A delivery quality assurance plan was prepared for the established IMRT plan and the dose distribution in the actual motion condition was measured and analyzed using a two-dimensional diode detector placed on a moving phantom capable of simulating breathing movements. The dose measurement was performed considering only a uniform target shape and motion in the superior-inferior (SI) direction. In this condition, it was confirmed that the error of the dose distribution due to the target motion is minimum in tomotherapy. This is thought to be due to the characteristic of tomotherapy that treats the target sequentially by dividing it into several slices. When the target shape is uniform and the main target motion direction is SI, it is considered that tomotherapy for the ITV-based IMRT method has a characteristic which can reduce the dose difference compared with the plan dose under the target motion condition.

The Improvement of Target Motion Analysis(TMA) for Submarine with Data Fusion (정보융합 기법을 활용한 잠수함 표적기동분석 성능향상 연구)

  • Lim, Young-Taek;Ko, Soon-Ju;Song, Taek-Lyul
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.12 no.6
    • /
    • pp.697-703
    • /
    • 2009
  • Target Motion Analysis(TMA) means to detect target position, velocity and course for using passive sonar system with bearing-only measurement. In this paper, we apply the TMA algorithm for a submarine with Multi-Sensor Data Fusion(MSDF) and we will decide the best TMA algorithm for a submarine by a series of computer simulation runs.

Target Motion Analysis for Active/Passive Mixed-Mode Sonar Systems

  • Taek, Lim-Young;Lyul, Song-Taek
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.172.5-172
    • /
    • 2001
  • Target Motion Analysis(TMA) for Passive Sonar Systems with bearing-only measurements needs to enhance system observability to improve target tracking performance by ownship maneuvering. However, tracking problem incurred by weak observaility result in slow convergence of the target estimates. On the other hand, active sonar systems do not have problem associated with system observaility. However, it drawback related to system survivability. In this paper, the algorithm that could be used in Active/passive Mixed-Mode Sonar Systems is proposed to analyze maneuvering target motion and to improve TMA performance. The proposed TMA algorithm is tested by a series of computer simulation runs and the results ...

  • PDF

A Study on the Aperiod Bearing Only TMA (비주기 Bearing 표본입력에 대한 BOTMA 연구)

  • 이동훈
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.4 no.1
    • /
    • pp.30-40
    • /
    • 2001
  • This paper presents a study on the design and simulation of bearing only target motion analysis to enhance the TMA capability using SONAR in underwater environment. A bearing only target motion analysis algorithm using aperiod bearing input signals has been developed and simulated in the MATLAB.

  • PDF

Batch Time Interval and Initial State Estimation using GMM-TS for Target Motion Analysis (GMM-TS를 이용한 표적기동분석용 배치구간 및 초기상태 추정 기법)

  • Kim, Woo-Chan;Song, Taek-Lyul
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.18 no.3
    • /
    • pp.285-294
    • /
    • 2012
  • Using bearing measurement only, target motion state is not directly obtained so that TMA (Target Motion Analysis) is needed for this situation. TMA is a nonlinear estimation technique used in passive SONAR systems. Also it is the one of important techniques for underwater combat management systems. TMA can be divided to two parts: batch estimation and sequential estimation. It is preferable to use sequential estimation for reducing computational load as well as adaptively to target maneuvers, batch estimation is still required to attain target initial state vector for convergence of sequential estimation. Selection of batch time interval which depends on observability is critical in TMA performance. Batch estimation in general utilizes predetermined batch time interval. In this paper, we propose a new method called the BTIS (Batch Time Interval and Initial State Estimation). The proposed BTIS estimates target initial status and determines the batch time interval sequentially by using a bank of GMM-TS (Gaussian Mixture Measurement-Track Splitting) filters. The performance of the proposal method is verified by a Monte Carlo simulation study.

A Study on Performance Improvement of Target Motion Analysis using Target Elevation Tracking and Fusion in Conformal Array Sonar (컨포멀 소나에서의 표적고각 추적 및 융합을 이용한 표적기동분석 성능향상 연구)

  • Lee, HaeHo;Park, GyuTae;Shin, KeeCheol;Cho, SungIl
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.22 no.3
    • /
    • pp.320-331
    • /
    • 2019
  • In this paper, we propose a method of TMA(Target Motion Analysis) performance improvement using target elevation tracking and fusion in conformal array sonar. One of the most important characteristics of conformal array sonar is to detect a target elevation by a vertical beam. It is possible to get a target range to maximize advantages of the proposed TMA technology using this characteristic. And the proposed techniques include target tracking, target fusion, calculation of target range by multipath as well as TMA. A simulation study demonstrates the outstanding performance of proposed techniques.

Vision-Based Obstacle Collision Risk Estimation of an Unmanned Surface Vehicle (무인선의 비전기반 장애물 충돌 위험도 평가)

  • Woo, Joohyun;Kim, Nakwan
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.21 no.12
    • /
    • pp.1089-1099
    • /
    • 2015
  • This paper proposes vision-based collision risk estimation method for an unmanned surface vehicle. A robust image-processing algorithm is suggested to detect target obstacles from the vision sensor. Vision-based Target Motion Analysis (TMA) was performed to transform visual information to target motion information. In vision-based TMA, a camera model and optical flow are adopted. Collision risk was calculated by using a fuzzy estimator that uses target motion information and vision information as input variables. To validate the suggested collision risk estimation method, an unmanned surface vehicle experiment was performed.

Target Motion Analysis with the IMMPDAF for Sonar Resource Management (IMMPDAF를 Sonar Resource Management에 적용한 기동표적분석 연구)

  • 임영택;송택렬
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.53 no.5
    • /
    • pp.331-337
    • /
    • 2004
  • Target motion analysis with a sonar system in general uses a regular sampling time and thus obtains regular target information regardless of the target maneuver status. This often results in overconsumption of the limited sonar resources. We propose two methods of the IMM(interacting Multiple Model) PDAF algorithm for sonar resource management to improve target motion analysis performance and to save sonar resources in this paper. In the first method, two different process noise covariance which are used as mode sets are combined based on probability. In the second method, resource time which are processed from two mode sets is calculated based on probability and then considered as update time at next step. Performance of the proposed algorithms are compared with the other algorithms by a series of Monte Carlo simulation.

A Robust Target Motion Analysis Algorithm for Discontinuous Frequency Measurements (불연속적인 다중 주파수 측정치에 강인한 표적기동분석 알고리즘)

  • Cheong, Myoung-Jun
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.14 no.3
    • /
    • pp.372-379
    • /
    • 2011
  • Estimating underwater target state variables(position, velocity, course, etc) is necessary to counteract threatening targets. In passive sonar systems, conventional target motion analysis(TMA) techniques using bearing and frequency measurements of an underwater target are widely introduced. However, it is not clear how conventional TMA techniques can be used if some of frequency measurements are unavailable during parts of the scenario, partially unavailable frequency measurements are common in the ocean with complicated acoustic conditions where frequency measurements often come and go. This paper proposes a new TMA algorithm, which is robust to partially unavailable frequency measurements, using the frequency measurements fusion method.

Study on Bearing and Frequency Target Motion Analysis for Passive Line Array SONAR Using Accumulative Batch Estimation (누적 일괄추정 기법을 이용한 수동 선배열 소나 방위 주파수 - 표적기동분석 연구)

  • Kim, In-Soo
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.22 no.10
    • /
    • pp.788-796
    • /
    • 2016
  • Bearing and frequency measurements of TMA (Target Motion Analysis) in passive line array SONAR have lower bearing rate and frequency doppler, and are not detected or tracked continuously because of various ocean environments. This is a main reason to effect the TMA performance and it takes a long time to get TMA solutions. We propose the bearing and frequency TMA(BFTMA) using accumulative batch estimation to solve the TMA problem of line array passive SONAR. The accumulative batch estimation structure is based on MLE (Maximum Likelihood Estimation) but used accumulative measurements. The accumulative batch estimation is applied for the BFTMA with nonlinear Kalman filter to estimate the target range, speed and course. Simulation and sea data analysis were carried out to verify the performance and applicability of the proposed techniques.