ground

A tornado is a rotating column of air from a thunderstorm to the ground, almost all of which occur in the US.

Hurricanes are strong tropicalstorms,which usually occur in the southern Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico.

This is a story about the 1900 Galveston hurricane. The most violent have winds of more than每小时400公里 Tornadoes can （卷起）cars, trains and even houses and把它们扔下来 in the next steet--or enen in the next town. They can- the fur - the back of a cat and the feathers -a chicken. They can- hous

商照飞行员地面理论课程

Ground lesson .5

商照飞行员地面理论课程

商照飞行员地面理论课程

Weight and Flight Performance A heavier gross weight will result in: Longer T/O/LDG roll, shallower climb, faster touchdown speed, slow acceleration/deceleration Increased retarding force (drag and ground friction)

Climb and cruise performance is reduced which can lead to: Overheating in climbs, added wear on engine, increased fuel, slower cruise, reduced range

商照飞行员地面理论课程

Weight and Structure Structural failures which result from overloading may be catastrophic but they ofte

商照飞行员地面理论课程

Ground lesson .5

商照飞行员地面理论课程

商照飞行员地面理论课程

Weight and Flight Performance A heavier gross weight will result in: Longer T/O/LDG roll, shallower climb, faster touchdown speed, slow acceleration/deceleration Increased retarding force (drag and ground friction)

Climb and cruise performance is reduced which can lead to: Overheating in climbs, added wear on engine, increased fuel, slower cruise, reduced range

商照飞行员地面理论课程

Weight and Structure Structural failures which result from overloading may be catastrophic but they ofte

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING,VOL.38,NO.4,JULY20001513 Three-Dimensional FDTD Modeling of a

Ground-Penetrating Radar

Levent Gürel,Senior Member,IEEE,and U?g ur O?g uz

Abstract—The finite-difference time-domain(FDTD)method

is used to simulate three-dimensional(3-D)geometries of realistic

ground-penetrating radar(GPR)scenarios.The radar unit is mod-

eled with two transmitters and a receiver in order to cancel the

direct signals emitted by the two transmitters at the receiver.The

transmitting and receiving antenna

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A Ground-Based Search for Thermal Emission from the Exoplanet TrES-1Heather A.Knutson,David Charbonneau 1Harvard-Smithsonian Center for Astrophysics,60Garden Street,Cambridge,MA 02138hknutson@aa004c86ec3a87c24028c415,dcharbonneau@aa004c86ec3a87c24028c415 Drake Deming Planetary Systems Laboratory,Code 693,Goddard Space Flight Center,Greenbelt,MD 20771ddeming@aa004c86ec3a87c24028c415 and L.Jeremy Richardson Exoplanet and Stellar Astrophysics Laboratory,Code 667,Goddard Space Flight Center,Gre

We study the zero-temperature phase diagram of the 2D quantum $J_{1}^{XXZ}$--$J_{2}^{XXZ}$ spin-1/2 anisotropic Heisenberg model on the square lattice. In particular, the effects of the anisotropy $\Delta$ on the $z$-aligned N\'{e}el and (collinear) stripe

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8E?ect of anisotropy on the ground-state magnetic ordering of the

spin-half quantum J XXZ 1–J XXZ 2model on the square lattice

R.F.Bishop,1,2P.H.Y.Li,1,2R.Darradi,3J.Schulenburg,4and J.Richter 3

1School of Physics and Astronomy,Schust

在电子电路中，常可以看到VCC、VDD和VSS三种不同的符号，它们有什么区别呢？

一、解释

V C C : C = ci rc u it 表示电路的意思，即接入电路的电压；VDD : D = device 表示器件的意思，即器件内部的工作电压；

V S S : S=series 表示公共连接的意思，通常指电路公共接地端电压。

二、说明

1、对于数字电路来说，VCC是电路的供电电压,VD D是芯片的工作电压（通常Vcc>Vdd ） , VSS是接地点。

2、有些IC既有VDD引脚又有VCC引脚，说明这种器件自身带有电压转换功能。

3、在场效应管（或COMS器件）中，VDD为漏极，VSS为源极，VDD和VSS指的是元件引脚，而不表示供电电压。

说法一：

VCC、VDD、VEE、VSS是指芯片、分解电路的电源集结点，具体接电源的极性需视器件材料而定。VCC 一般是指直接连接到集成或分解电路内部的三极管C极，VEE是指连接到集成或分解电路内部三极管的E极。同样，VDD、VSS就是指连接到集成内部、分解电路的场效应管的D和S极。例如是采用P 沟E/D MOS工艺制成的集成，那么它的VDD就应接电源的负，而VSS应接正电源。

它们是这样得名的：

VC C表示连接到三极管集电极