Staples has started lower Ultrabooks to $599 (Lenove and Toshiba, since Toshiba is Japanese brand also with plastic cover, and Lenovo is metal cover , we should buy Lenovo). I bet Surface Pro price will start from the same $ 599.99 price or lower.
【在 d*******e 的大作中提到】 : Staples has started lower Ultrabooks to $599 (Lenove and Toshiba, since : Toshiba is Japanese brand also with plastic cover, and Lenovo is metal cover : , we should buy Lenovo). I bet Surface Pro price will start from the same $ : 599.99 price or lower.
【在 d*******e 的大作中提到】 : The one in Staples is not the Carbon X1
k*z
23 楼
美国自杀的岂不是要上百万
【在 f**********r 的大作中提到】 : 按这标准,国内怎么着也最少自杀千把个
l*n
24 楼
This is absolutely wrong. The sensors sense simultaneously, so you cannot tell who leads who. You can only detect who detect white or black first. So you need 3 sensors. First place sensor 1, then sensor 2 is placed in a position with clockwise angle less than 180 degree, then place sensor 3 with clockwise angle more than 180 degree. For the three sensors, there must be two detecting the same color, the other detecting the other color.
【在 o*******5 的大作中提到】 : agree. it is a common problem for some old houses
S*r
27 楼
U300s i guess
D*a
28 楼
那得腾出来多少新坑啊 *_*
【在 k****z 的大作中提到】 : 美国自杀的岂不是要上百万
l*n
29 楼
Just one example, When 2 detects white, 1 and 3 detects black. Then we can check whether 1 or 3 detects white first. If 1 detects white first, counterclockwise; otherwise clockwise. The reason to add another sensor is to add a pivot for checking what color should be detected for the next time. (You should determine what color you detect next time, then you can tell who leads who)
. other
【在 l***n 的大作中提到】 : This is absolutely wrong. The sensors sense simultaneously, so you cannot : tell who leads who. : You can only detect who detect white or black first. So you need 3 sensors. : First place sensor 1, then sensor 2 is placed in a position with clockwise : angle less than 180 degree, then place sensor 3 with clockwise angle more : than 180 degree. : For the three sensors, there must be two detecting the same color, the other : detecting the other color.
This is shocking. He has made so many important contributions.
l*n
33 楼
If there are only two sensors, suppose the direction is clockwise, Suppose for the first time 1 and 2 simultaneously detect black, if 1 is closer to black-white edge, then 1 detect white first; if 2 is closer to the black-white edge, then 2 detect white first. So you can never tell the direction is clockwise
Sorry, I was wrong about something. The reason to add another sensor is to add a pivot for checking who is closer to the black-white edge. And another condition is that the angle between sensor 2 and sensor 3 should also be less than 180 degree in clockwise. For instance, the sensor 1, 2 3 can evenly distribute on the circle with 120 degree between each pair. So the sequence wwb->wbw (or bww) can tell the rotation direction.
I think one sensor should be good to go. let's say the music disc spin 0.5 circle/per second, and the sensor sampling interval is 10ms , use 3 sampling to remove the noise to decide current status or status change. we define the status to be the zone current sensor is in, white, black, and also transition from "white to black " and "black to white" could be detected. it is similar to key board scanning to detected the key pressed and released