都卜勒效應如果注意聽火車的汽笛聲，你會發現火車自遠方來時笛聲悠揚，離你而去實則低鳴如訴。火車上的汽笛頻率是一定的，聽起來卻因火車的接近或離去而不同；這現象在一八四二年就由一位奧國科學家叫做都卜勒(J.C.Doppler,1803–1853)的人提出，叫作都卜勒效應(Doppler effect)。這個效應原理是只要聲源、聽者以及傳播波動的介質有相對運動，就會有都卜勒的效應出現。被運用在氣象雷達, 雷達. 甚至到網路品質ping.由都卜勒效應延伸到聲納聲納「聲波導航和測距」（sound navigation and ranging, sonar）是一種向海底發射並接收回聲以測量海洋深度的方法，藉由這個訊號接觸物體後反射回來的變化，做為計算這個物體的相對方位與距離的資料。
PING 現代科技中網路監測, 怎麼知道對方關機了, 網路品質狀況?
ping 用來測試封包能否通過IP協定到達特定主機。ping的運作原理是向目標主機傳出一個ICMP echo 要求封包(Internet Control Message Protocol)，並等待接收echo回應封包(Echo Request/Reply exchange)。程式會按時間和成功響應的次數估算遺失封包率（丟包率，Packet loss）和封包往返時間（網路時延，Round-trip delay time）。
在這份 RFC1122 的 3.3.1.4 提到 ping .(ietf.org)
附上市面上免費的 ping 比較表,
source:
http://www.linksoft.com.tw/products.asp?seq=1224
www.nirsoft.net
www.pingplotter.com
ietf.org
GIVE
ME THE LEVER LONG ENOUGH …AND SINGLE-HANDED I CAN MOVE THE WORLD.
The lever would bring and present the ability to target specific points within the system to that would render tremendous efficiencies. Peter Senge noted this is the lever is one of the necessity of the learning organization.
Another thing need to consider is the "Prisoner of our thinking", but we will talk about this in later chapter.
today, i would introduce the 7 learning disabilities, they are common and do exist among the organizations.
we always think about how organization can be more innovative, but if we ignore these noises from the 7 things in organization, it would be totally waste time and resources. try to find the positive strength and the possible weakness areas and the organization will be the winner from the dynamic world race.
here's the suggestion for you to consider when you tend to design a customer service survey !
