射束

• Secondly , a beam - hardening correction algorithm for single material object is given in the paper , which is more precise than polynomial approaching correction algorithm and more rapid than common iterative algorithm
  其次，本文给出了单成分被测物体的射束硬化校正算法，该算法较多项式近似校正算法更加精确，并且显著快于一般的迭代算法。
• In this thesis , ga is used to optimize the beam weights of intensity modulated radiation therapy ( imrt ) inverse planning , and 2d and 3d isodose contour as well as dose volume histogram ( dvh ) are used to evaluate the treatment plan
  本文应用遗传算法优化逆向调强放疗计划中射束的权重，用二维等剂量线、三维剂量分布和剂量体积直方图来评估计划的优劣。
• In order to eliminate the beam - hardening artifacts , most current correction algorithms have to assume that the x - ray beam spectra are known and the mass attenuation coefficients of the detected object related to different energy are given
  目前的多数射束硬化校正算法需假设已知ct系统的x射线能谱，并已知构成被测物体的物质关于不同能量的光子的质量衰减系数。
• Otherwise the progressing nuclear engineering makes it possible to improve the quality of neutron beams ; and combined with the developing tumor - localizing boron compounds , bnct will be more effective and more useful for cancer treatment
  另一方面，核能技术的进步也促使中子射束的品质有所改进；配合含硼寻癌药的发展，硼捉中子治疗的效果应该可以更好，于癌病治疗上的应用?围可以更广。
• All that we need to carry out the tests are appropriate particle colliders ? ones that have sufficient energy to produce the different higgs bosons , sufficient intensity to make enough of them and very good detectors to analyze what is produced
  我们需要的只是适当的粒子加速器，以便有足够的能量和射束强度来制造种类各异且数量充足的希格斯粒子，再加上优良的侦测器以分析所制造出来的东西，就能从事实验。
• Also , a beam - hardening correction research on the double - material object is given . and the numerical experiment results show that the beam - hardening artifacts can be eliminated in the reconstructed image using the latter algorithm , furthermore , it can be applied to multi - material object
  本文也对双成分被测物体的射束硬化校正算法进行了探讨，数值实验表明，算法较好地消除了重建图像中的射束硬化伪迹，该算法还可进一步推广到多成分被测物体的情形。
• Advanced mathematical technologies , especially the newly developed wavelet transform and the frame theory , provide a solid foundation for such an effort . the ray - theory based beam - summation method , such as the complex source - generated beam and the gaussian beam methods , and the local phase - space domain ( beamlet domain ) wave field extrapolation methods employing windowed fourier transform ( wft ) or wavelet transform are proposed consequently
  基于射线理论的高频渐近射束(复射束、高斯射束)叠加方法，以窗口富里叶变换( wft )以及小波变换为基础的局部相位-空间域(小波束域)波场外推方法等相继产生。