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g*****e
发帖数: 10097 | 2 俺看了下各位的经验贴，不知道自己遗漏了什么没有，应该需要：
1。backflow preventer
1. Pressure regulator
200 feet drip tube
若干 1gph emitter, 18寸装一个
1。drip tube fitting
1. air vent
1. end cap
俺要用的那块地约200sqft，这样应该够了吧？
非常感谢各位大牛支招。 |
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g*****e
发帖数: 10097 | 3 真的？这么好！也就是说只需要1/2寸管子和emitter若干就行了？ |
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g*****e
发帖数: 10097 | 4 厉害啊，非常葱白，俺举手提问：
1。旧的喷水系统怎么挖掉？挖了整整一个zone的？
2。 平行的管子们另外一头是怎么个状况？连在一起还是一人一个end cap?
3。 凑近点瞧瞧你的emitter?
4. 管子们用U形针固定了么？ |
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h**w
发帖数: 4510 | 6 amazon的那个主要是dripper，适合大棵植物。lowes的主要是sprayer适合大片植物。
滴灌是因地，因植物置宜，主管路都相似，到了emitter这儿就看你自己怎么配了。 |
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h**w
发帖数: 4510 | 7 质量没法说，我除了买的filter质量差没法用之外，别的都还好。我没买过kit，都是
自己买零件配的。
这个kit配的是dripline，就是固定喷头的水管，我平时用这个是最多的，很适合在菜
地里种一到二尺间距的植物。安装最容易，一根dripline从总管出来可以把整个菜地都
绕到，不用分装emitter。 |
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h**w
发帖数: 4510 | 8 你用in line emitter就没这个问题了。实际效果和1/2一样。你这样接法，一般是用在
很大棵和不规则的地方，菜地不是这么弄的。
L |
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l*****u
发帖数: 12114 | 9 built-in emitter最大的问题是一旦坏了怎么办？比如一锄头搞断了。用一般1/2管子
的维护费用很低。
地的 |
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l*****u
发帖数: 12114 | 12 如果管子是1/4的就直接插这个dripper的两段。如果管子是1/2的就换种emitter在1/2
管子上戳洞。 |
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z*********n
发帖数: 94654 | 13 那我就买条巨长的1/2应该就够了吧，然后扎emitter |
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h**w
发帖数: 4510 | 14 不推荐活着的清华大学那种。反正菜地1/4 tubine＋emitter是最糟的。 |
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c***p
发帖数: 27645 | 17 具体多少没算过，我家大概连了30多个头，已经觉得压力不够了 |
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i***h
发帖数: 12655 | 18 滴灌压力小点没关系吧
慢慢滴就行对吧
我现在是那种小喷头，还嫌它不好控制范围 |
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n*******d
发帖数: 1430 | 19 我对滴灌的学习是从农友给我的这个link开始的. http://www.dripking.com/pdf/installationguides.pdf
当时流览之后有了初步了解, 但是并没有马上动手, 因为从概念到具体实践还是有一定
距离, 没有一个parts list可以依葫芦画瓢. 再经过一年断断续续的琢磨, 去年5月
选定以dripdepot.com为主采购材料设计方案并获得一次性组装成功及投入使用. 它家
价格适中而且$49以上就free shipping, 质量方面至少我现有的系统使用一年之后无任
何问题. 常有朋友问我怎么装滴灌, 在这里我把我的经历/经验毫无保留的写出来,希望
给大家科学种地提供有益的借鉴.
主管的选择: 我用了差不多240 feet的3/4’’管, 而不是1/2’’管,实践表明无论滴
还是喷完全没有压力不足的问题.
从garden faucet开始接, 从右到左依次是timer, filter, 30 PSI pressure reducer,
swivel adapter, 一段3/4’’管, tee. 到主管的通路至此完成. 30 PSI是必要的,... 阅读全帖 |
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b********y
发帖数: 334 | 20 今天为了这个滴灌，跑了homedepot3次，呵呵，终于大功告成。
补充一点，timer后面需要接一个25psi pressure regulator要不水压过大，容易把
drip emitter冲掉，而且不接regulator压力大，水流过快。
考古了一下，参考了北木大师的贴子里的滴灌。 |
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t****g
发帖数: 35582 | 21 那就是我说的那样，直接把50um宽的emitter粘在edge上啦。 |
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a******e
发帖数: 17 | 22 以下是我一个哈佛物理博士朋友的回答。但愿能给你一点安慰。。。
Our family is planning a east coast vacation (for real) to outrun the
nuclear cloud drifting our way... I am kidding, but you may find the
following information entertaining, and potentially educational.
We need to put any risk in perspective. The main stream media is playing a
constructive roles here to report the risk as justified by the information
available and by the possible worst-case scenarios. Risk cannot be
discussed without quantification, otherwise i... 阅读全帖 |
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c****t
发帖数: 19049 | 26 An international team of scientists says it's figured out how to slow global
warming in the short run and prevent millions of deaths from dirty air:
Stop focusing so much on carbon dioxide.
They say the key is to reduce emissions of two powerful and fast-acting
causes of global warming — methane and soot.
Carbon dioxide is the chief greenhouse gas and the one world leaders have
spent the most time talking about controlling. Scientists say carbon dioxide
from fossil fuels like coal and oil is a b... 阅读全帖 |
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B******1
发帖数: 9094 | 27 I am thinking that all swimming pools should have intelligent scanning
device that could detect human-like floating objects dropping to the bottom
of floor and stopped moving. If triggered, the alarm should lead rescuer to
the exact position where such suspicious "body" is detected. The simplest
one would be a sonar device for such purpose. In addition, each swimmer can
wear an emitter or tag to enhance the signal. |
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D*****e
发帖数: 761 | 28 谢谢诸位了。
我好好google了一下，总算明白这个就是个ZCam了。
http://en.wikipedia.org/wiki/ZCam
所以这个不是基于三角测量的，主要是 time-of-flight 面阵LiDAR, MS出示的图上的
所谓两个camera, 其实一个是IR laser emitter, 另一个才是time-of-flight camera.
有总结不对的地方请指教。要是有Windows driver就好了，我可以自己开发点游戏。 |
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g***u
发帖数: 5413 | 29 只有一些DLP 3D HDTV支持，不少人是用120Hz显示器。
好像是通过HDMI传到电视的信号没有同步信息(或者电视不能接收），所以要再接IR
emitter，这个nvidia
3d vision kit里面带。
nvidia |
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k***r
发帖数: 13724 | 30 我用nvidia+3d monitor, nvidia自己的眼镜是要IR emitter的. 3dtv play没用过,我
在电脑上看3d电影都是用powerdvd12 ultra. 这个软件还能把你的普通2d视频/图片转
成3d的,很爽. |
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g***u
发帖数: 5413 | 31 说错了，是DLP电视要再接VESA Cable来传同步信息。IR emitter是给眼镜 |
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l********l
发帖数: 9452 | 33
nvidia
IR
emitter hack只能用在285.62一下，新显卡都没戏。买一个3dtv play就是了，也就一
顿饭钱。
我的tv是costco买的sharp 70C8470，接上显卡就直接能用，自带的glass比较矬，现在
用的是sony的，很舒服。btw sharp的3d tv register的时候会送你3d blue-ray，就在
那个AQUOS.net选，有很多岛国av......我选了5部3D CatWalk Poison，vol2是女神小
泽哦。70寸的3d电视看小泽xxoo...很给力啊 |
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i****x
发帖数: 17565 | 34 你那个国内烂校学报的”科研“结论跟以下所有结论矛盾的时候，你说我们该信谁呢？
In 2006 a large Danish group's study about the connection between mobile
phone use and cancer incidence was published. It followed over 420,000
Danish citizens for 20 years and showed no increased risk of cancer.[21] A
2011 follow-up confirmed these findings.[22]
The following studies of long time exposure have been published:
The 13 nation INTERPHONE project – the largest study of its kind ever
undertaken – was published in 2011 and did not find a solid li... 阅读全帖 |
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n*******s
发帖数: 482 | 35 Node in Action 的例子代码 讲emitter的
关于这一行
this.on('broadcast', this.subscriptions[id]);
我是不是可以理解成
1. 当channel.emit('join', id, client)时候，'broadcast' event被注册(to be
listened by channel object)
2. 当channel.emit('broadcast', id, data)时候，'broadcast'被emit，因为channel
一直在listen这个event，从而invoke 'this.subscriptions[id]'
3. 实参id, data替换了this.subscriptions[id]里面的形参[senderId, message]，函
数可以执行
4. 尽管函数this.subscriptions[id]体内的变量:id并非形参，因为语言是动态的，所
以在执行时候 函数”this.
subscriptions[id]“是知道id的值的，所以函数可以正确执行？
是在觉得怪怪的，请教一下大家... 阅读全帖 |
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m**o
发帖数: 13 | 37 P32 has a little bit high emission of beta particles. Beta particles are
completely attenuated by small thicknesses of common materials.Therefore, they
do not pose an external source of radiation dose. Even a high energy beta
particle from a P-32 decay event can only penetrate about 8 millimeters of
tissue. Our radiation-sensitive organs are typically at least 12 to 25
millimeters below the skin surface. However, a beta emitter can cause
radiation dose if ingested. So don't worry too much.
And u |
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A*******l
发帖数: 67 | 38 我觉得你说的monochromator是那种specific single wavelength light input device
.我见到的那台是single channel light emitter，连接别的detector 和sample
chamber用作fluorometer
很少有人把UV/vis叫monochromator吧，虽然原理上它包括某种monochromator作为光源。
Xenon flash lamp 和DT就看个人爱好。DT比较传统，但是除非你买5000/6000系列，不
然我觉得performance差不多。 |
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Y********t
发帖数: 14 | 39 If the AM signal is strong, it's easy to demodulation it by
using a diode and a cap. This is what is called Bao Luo
Jian Bo. I believe this is what happened. The emitter of
the output transistor is actually a diode, which charges and
discharges the speaker. (Of course the demodulation can
happen anywhere in the signal path. But it has to be "Bao
Luo Jian Bo" because there is no local-oscillator.)
Bao Luo Jian Bo is because of the
one-way conductivity of diode. To be sure, one-way
conducti |
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s***l
发帖数: 2236 | 40 The original question is about the spacial mode of a laser, not how the
shape deforms in fiber or any media when the light propagates, not to
mention frequency domain, which is almost completely irrelavant.
For a confocal resonator, the spacial mode can be analytically solved to
be Hermite-Gauss functions, in which the TEM00 mode corresponds to a simple
2D Gaussian beam.
So for edge-emitting LD, the spacial mode should be 2D Gaussian beam, although
not degenerated since the ratio of the dimentio |
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f*****0
发帖数: 489 | 41 making a power supply that can output 0v, and goes over 0-150v is pretty
difficult.
you didn't specify maximum current, but assume that it is quite small (<10ma
), you may be able to just use a typical linear supplier (emitter follower)
where you use your 0-5v signal to control a small signal transistor sitting
on the base of a large power transistor to control an output voltage.
However, the power dissipation over that power transistor will be
significant (like 1.5w) and would definitely need a |
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z*********n
发帖数: 35 | 42 好像问我知不知道有PMOS 做在 P-well 里面的，弄得我晕
bala, bala,还说了不少优点
请教大牛这是什么技术，那里可以找到reference呵？
还有，in terms of gain, poly-emitter 比 metalization 好在哪里？
要从carrier flow 上面解释
多谢了，大虾解惑 |
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i******l
发帖数: 55 | 43 pmos一般做n-well里面吧
poly-emitter比metalization跟wafer结合的更好，在carrier flow上有什么优势还真
说不上来。不过这两个问题听起来都很有意思。
我也是二把刀，哪位大牛能解释一下？ |
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ET
发帖数: 10701 | 44 varactor for the pmos in the pwell.
just search "cmos varactor"
poly -emitter vs. metalization? doesn't sound they are talking about the
same thing. What's the whole story? |
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z*********n
发帖数: 35 | 45 好像问我知不知道有PMOS 做在 P-well 里面的，弄得我晕
bala, bala,还说了不少优点
请教大牛这是什么技术，那里可以找到reference呵？
还有，in terms of gain, poly-emitter 比 metalization 好在哪里？
要从carrier flow 上面解释
多谢了，大虾解惑 |
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f*****0
发帖数: 489 | 46 using an opamp is one approach.
another is to use a tl431-based bias generator.
or an emitter follower. |
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f*****0
发帖数: 489 | 47
the answer depends.
most bipolars are used for linear applications. For obvious reasons, they
cannot work in the saturation region. However, there are switching bipolars,
and emitter-switched bipolars as well as igbt that do work in their
saturation region.
mosfets are primarily for switching applications so they work mostly in
their saturation region. However, most lateral mosfets (older mosfets or
audio mosfets) work in their linear regions.
In the end, most devices can work comfortably in ei |
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c*u
发帖数: 916 | 48 需要我这个TA出马了 :-)
Vcc: Most time means voltage to the "C"ircuit, sometimes to collector in BJT
Vee: .. to emitter in BJT
Vdd: .. Most time means to "Device", sometimes to drain in MOSFET
Vss: .. to source in MOSFET
同学们，还有疑问么？ |
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f*****0
发帖数: 489 | 49 0.5v trigger is tough to do, as it wouldn't be enough to turn on a bjt.
a few posibilities:
a) you can use some depletion mosfet which conducts at all voltage types.
b) you can use a comparator, preferrably single rail type. like lm311.
c) form a 0.2 - 0.5v supply, and apply it to the base of a npn bjt. type
emitter of your bjt to your control signal, and your relay to the collector.
when the control signal is at 0.5v, the be junction doesn't get enough
signal to turn on the bjt so the relay sta |
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