近年来医学影像学发展很快,在CT、 MR、超声和核医学等方面都有了相当大的进展,特别是T、MR和PACS(Picture Archiving and Communication System) 的发展

1、鼻中隔脓肿最常见的病因是 A.鼻前庭疖 B.鼻旁窦炎 C.流感 D.猩红热 E.鼻中隔血肿继发感染 2、诊断鼻中隔脓肿最有价值的方法是 A.前鼻镜检查 B.病史 C.鼻中隔局部穿刺 D.X线拍片 E.CT检查

引言 一、包括肾脏、输尿管、膀胱、尿道 二、缺乏自然对比,需用造影检查 三、目前CT、USG、MR已广泛应用

Department of Electrical Engineering and Computer Science 6.003: Signals and Systems-Fall 2003 Thursday, November 13. 2003 Directions: The exam consists of 5 problems on pages 2 to 19 and additional work space on pages 20 and 21. Please make sure you have all the pages. Tables of Fourier series properties as well as CT Fourier transform and DT Fourier transform properties and pairs are supplied to you as a separate set of pages. Enter all your work and

Department of Electrical Engineering and Computer Science 6.003: Signals and Systems-Fall 2003 Final Exam Tuesday, December 16, 2003 Directions: The exam consists of 7 problems on pages 2 to 33 and additional work space on pages 34 to 37. Please make sure you have all the pages. Tables of Fourier series properties, CT and DT Fourier transform

Motivation for the Laplace transform CT Fourier transform enables us to do a lot of things, e. g Analyze frequency response of lTi systems Sampling Modulation Why do we need yet another transform? One view of Laplace Transform is as an extension of the Fourier

SAMPLING We live in a continuous-time world most of the signals we encounter are CT signals, e.g. x(). How do we convert them into Dt signals x[n? Sampling, taking snap shots of x(t) every Seconds

Another(important! ) example: Periodic Impulse train n(t)=∑(t Sampling function important for sampling .2T

Question: Are there sets of basic\ signals so that a) We can represent rich classes of signals as linear combinations of these building block signals b) The response of ltI Systems to these basic signals are both simp and insightful Fact: For LtI Systems(CT or dt) there are two natural choices for these building blocks Focus for now:

EROSPACE DYNAMiCS EXAMPLE: GWE ACCELERATIoN of THE TIP 0F认ERU0毛R人TM5Hc人AF LDk小 G For A650LUT # CCELER升T10 N UTH RES/∈ct T0wE工NERT1 AL FRAME (∈ TH IN THiS CASE)