Cyclic Codes a cyclic code is a linear block code where if c is a codeword, so are all cyclic shifts of c E.g., 1000, 110, 101,011 is a cyclic code Cyclic codes can be dealt with in the very same way as all other lbc s Generator and parity check matrix can be found a cyclic code can be completely described by a generator string G All codewords are multiples of the generator string In practice, cyclic codes are often used for error detection(CRc) Used for packet networks When an error is detected by the received, it requests retransmission

CSMA/CD and Ethernet Two way cable wsws Ws W CSMA with Collision Detection(CD)capability Nodes able to detect collisions Upon detection of a collision nodes stop transmission Reduce the amount of time wasted on collisions Protocol

Automatic repeat request (ARQ) Break large files into packets FILE PKT PKT PKT Check received packets for errors Use a feedback channel to request retransmissions Retransmit packets containing errors acket Receive ACK

Electrical Power System EPS Power Energy Power Power Regulation Source Storage Distribution and Control

OVERVIEW OF THE EFFECTS OF THE SPACE ENVIRONMENT Outgassing in near vacuum Atmospheric drag Chemical reactions Plasma-induced charging Radiation damage of microcircuits, solar arrays, and sensors single event upsets in digital devices Hyper-velocity impacts

Goal: Give necessary optics background to tackle a space mission, which includes an optical payload Light .Interaction of light w/environment o Optical design fundamentals Optical performance considerations .Telescope types and CCd design interferometer types

ARGOS Overview Angular Resolution at 2=550 nm: 5 arcsec Wavelength Regime 400-700 nm FOr (Field-of-Regard): 120(full cone)

第一节汽车的动力性指标

西华大学交通与汽车工程学院：《汽车理论》第三章 汽车动力装置参数的选定

第一节概述 操纵稳定性 a.汽车正确遵循驾驶员通过操纵机构所给定的方向的能力; b.汽车抵抗企图改变行驶方向干扰、保持稳定行驶方向的能力。 不能过分降低车速或造成驾驶员疲劳