needle
发表于 2025-3-25 04:28:43
Gengsheng Lawrence Zeng dermal bony plates, but a few possessed only a little armour and it is possible that many unossified and at present unknown forms existed. The known fishes fall into rather sharply defined taxa, the relations of which are not altogether clear. The earliest group, the heterostracans, appears in the
津贴
发表于 2025-3-25 10:10:44
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Harrowing
发表于 2025-3-25 14:33:12
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幼儿
发表于 2025-3-25 19:18:54
Gengsheng Lawrence Zengn this field over the last 30 years, which have in some respects made the first edition seriously out-of-date. The book is now inevitably longer, but its scope remains the same and the original approach has been main tained as far as possible. I have, however, undertaken a certain amount ofre arra
arterioles
发表于 2025-3-25 21:56:21
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肌肉
发表于 2025-3-26 00:58:29
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foreign
发表于 2025-3-26 08:14:37
Basic Principles of Tomography,raphic image can obtained from its measurements using two simple examples. The concept of projection is then explained. Next, the filtered backprojection image reconstruction method is introduced using a point source example. Finally, the concept of backprojection is discussed.
现晕光
发表于 2025-3-26 12:30:42
Parallel-Beam Image Reconstruction,he Fourier domain. From this theorem, many image reconstruction algorithms are derived. Among these algorithms, the filtered backprojection (FBP) algorithm is the most popular one, which consists of a ramp-filtering step and a backprojection step. The filtering can be implemented as a multiplication
GEAR
发表于 2025-3-26 15:27:32
Fan-Beam Image Reconstruction,not along parallel lines, the image reconstruction algorithms presented in Chapter 2 cannot be applied directly. This chapter uses the flat detector and curved detector fan-beam imaging geometries to illustrate how a parallelbeam reconstruction algorithm can be converted to user’s imaging geometry f
叙述
发表于 2025-3-26 19:56:23
Transmission and Emission Tomography,a. If the radiation sources are inside the patient, the imaging system acquires the emission data. For transmission scans, the image to be obtained is a map (or distribution) of the attenuation coefficients inside the patient. For the emission scans, the image to be obtained is the distribution of t