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Showing content with the highest reputation on 12/23/2009 in all areas

  1. Indeed. Mostly. With the exception of a few off-topic juvenile "tickle party" posters and no-life zombie-watchers we have an exceptional collective here. I was hoping to tap into that collective. That said, I will take what you said to heart. But I must respond later. I'm leaving to be with my family for Christmas. But I will be back next week. Happy Holidays to you and yours, Francois.
    1 point
  2. True, it's happened in the earth's past. The big difference between the carbonaceous era and now is that we've stripped the forests around the world and wood growth doesn't compensate for our increased "exhalations". As a matter of fact, CO2 is a greenhouse gas. One of many. That you don't believe its increase to be a problem is something, but it definitely is a greenhouse gas. What do you think is the major difference between Mars, Venus and Earth? In the past (way past, before those ice cores measurements), each of these three planets could have evolved to be hospitable to life. It happens that, to the best of current knowledge in the planetary science community, Mars' surface being colder than its sister planets, it trapped larger quantities of CO2 in its rocks in a process analog to your laboratory cryogenic vacuum pumps. The CO2 atmosphere thinned out (6 mbar pressure as of today) and there was very little greenhouse effect that could compensate its greater distance to the sun. Venus was exactly the opposite, as it didn't trap the CO2, it amplified to produce a thick atmosphere with, nowadays, a very complex atmospheric structure involving acid rain, nitrous oxides and dense clouds, most of which contribute highly to the greenhouse effect. Of course, no point in stating the obvious for Earth... So a higher CO2 content could be balanced by an increase in vegetation? Sure. Provided we let the vegetation grow. Provided also that those trees we cut are not replaced with millions of cows that exhale CO2 and produce methane in large quantities. Methane, by the way, is the third predominant greenhouse gas... but being equivalent to 21 times the greenhouse effect of CO2 by weight, we would indeed be wise to let more forests untouched. Methane is also very much present is permafrost, which is at risk of not staying permanent if we let the temperature rise too much. Would it be balanced by an increase in vegetation cover? Again, maybe... provided we don't cut the trees... Oh yeah, I said that already. Chicken and the egg: whichever came first. Is CO2 a pollutant. Yes and no. It's referred to as a "fund pollutant" when it's produced in greater quantity than the absorptive capacity of the environment. This means that it might not be a pollutant yet, depending on where you stand on this issue... I believe it is, but that's just me. I watched it and felt something was odd but couldn't put my finger on it. There is indeed a source with the graphs... And then it occured to me... The temperature scales depicted are wrong. Antarctica's average temperatures are never around the freezing point. I guess they're simply mixed up. I'm not saying this is a scam or anything... but it does illustrate that you can't always believe the data you're presented at face value. This is true when you watch Al Gore's documentary... but it's even truer when you watch a video on Youtube. Cross-referencing with real scientific data and making sure we cite other people which are not related to us that have done similar work (and building on them or refuting them) is the true way to scientific inquiry. I don't know why you accuse people on LAVA of being such illiterate people. If you want to tease us, please use some emoticons... Otherwise we might think you're being serious! I've found that people hanging here, and it's been said many times by others, are quite knowledgeable in many fields of interest. The first trait of collective intelligence I value when people communicate, is their ability to express themselves with the right words (sycophant, calumniable, etc.) , without making too many grammatical or orthographic mistakes. The large majority or English-speaking people here can write a concise text without notable errors, as well as many foreigners... This is truly an amazing bunch we have here.
    1 point
  3. When did we all decide to forget our grade school biology? CO2 is NOT a pollutant. We exhale it. Plants need CO2 to survive. And it does NOT cause the green house effect. In fact, higher concentrations of CO2 can cause an increase in the amount of global vegetation. That has happened in earth's past.
    1 point
  4. You can actually see the functions included in DLL with LabVIEW call function library node and it seems to match what is in the document. I have attached this screenshot to show the functions in the DLL. There are only three functions that you need to care, I think. Find device, read and write. I have also created simple found device vi. For the read and write functions, you need to know the register bits meanings and how to combine the low and high data to get the real meaningful data. That part you may need to ask the analog device or study the sensor documents. FoundDevice.vi
    1 point
  5. OH! OH! - I actually have a useful answer (as opposed to my earlier post) to this one because I do the same thing with classes. I have an ErrorLogger class that has three public methods - Start Daemon, Stop Daemon, and Enqueue Error. Any time you want to start logging errors, start the daemon, To log an error, just drop the Enqueue Error VI in the error wire. When you want to stop logging errors, just call Stop Daemon. The daemon opens a ref to the error queue and starts waiting for anything on the queue. The Start Daemon vi has controls that let the user set the path to the log file, the max error log size (it starts throwing away old messages when the max size is reached), and whether or not enable error dialogs. The Enqueue Error vi just has error in and error out terminals - it gets a ref to the error queue by name and closes it when it exits. The Stop Daemon just has error terminals (all of my VI's have error terminals) All of the other stuff (like whether or not the Start Daemon has to create a new directory to create the error log file and the daemon itself) is in the private methods of the class and the user needs never worry about any of that. The HUGE advantage of this approach over a single action engine is that the Enqueue Error vi is reentrant - one part of the code can be spewing errors and logging them (and my code often does ) while another part of the code that also could log errors isn't blocked waiting on the AE. Mark
    1 point
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