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excel trendline formula is inaccurate

While trying to create a graph with trendline to predict what a thermistor reading for a Prius’s radiator/engine temperature would be at certain temperatures I started battling MSFT’s Excel.

I created a chart with the known data collected about the voltage at the thermistor for  a list of temperatures.  I wanted a trendline to show the calculation so that I could use it to calculate the resistance of the thermistor at those temperatures.  However, after creating a chart and looking at the trendline formula’s calculation of known data, something was completely screwed up.

After some Google searches there was a link to Microsoft’s Help and Support website that indicated that

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it's the word, the word, the word…

Last week I was disparately looking for something good to listen to on the radio while I was driving around Atlanta, GA.  The radio stations in Atlanta seemed to have taken a horrible step in the wrong direction in the last 10 years… But I digress.

While pressing the radio’s seek button like frogger to avoid the massive number of rap stations I heard the end of some 70s sounding song with “It’s the word, it’s the word, it’s the word…”  Damn, why does that sound so familiar?

Right!  It was a sample in track two of “the word” from the Swordfish soundtrack by Paul Oakenfold.

Again, my music friend

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Sending DHCP IP based on clients hostname

I’m working on a project where I need my DHCP server to send an IP address from a specific DHCP range if the hostname is a certain value otherwise it needs to send a normal IP address range.

I’m using Internet Systems Consortium DHCP Server V3.0.3 (ISC-DHCP).

To give a specific address range, we first need to detect if the DHCP client is sending the option 12 host-name and if so assign it to a class.

class “FooBar” { match if (option host-name = “foobar”); }

Once the client has a class associated to it we need to give it an address from a pool that doesn’t deny it.

subnet

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no network provider accepted the given path

I received the following error today when trying to open a samba share on a FreeBSD system from a clean Windows Server 2003 install:

“no network provider accepted the given path.”

“PC LOAD LETTER, what the fsck does that mean?!” I thought to myself. After some digging, I found that the default LAN Manager authentication level is set to NTLM response only and not LM & NTLM response.

Fix for the issue:

Administrative tools -> Local Security Policy -> Local Policy -> Security Options

Change: Network security: LAN Manager authentication level

From: Send NTLM response only

To: Send LM & NTLM responses

Solar water heating

I recently created a solar water heater for a pool in France. Since I had a limited set of tools and could not make anything permanent I had to use materials that were cheap and reusable or recyclable. What I ended up with was a 50 meter long by 13 millimeter in diameter irrigation hose.

Plastic is an absolutely horrible heat conductor. Most people who use irrigation hose for solar water heating live in areas where it is hot and sunny and/or does not get very cool. Or they do not care about the absolute best efficiency of their solar collector.

Even though I knew that plastic is a terrible

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How to: Make a cheap monitor stand

A while ago, I picked up a several 17″ LCD monitors for pocket change. They were old monitors from a school district in the Seattle area that had upgraded their computers. The only problem with the screens was that they didn’t have any stands. I’ve had the screens for almost a year and I haven’t used them solely because I haven’t found a stand for them. Today, I finally gave up finding cheap stands and just made some. The following is a quick how to make a LCD monitor stand.

Materials: acrylic sheet (anything larger than 32cm x 12cm and 0.23622 cm thickness) aluminum foil ruler drill drill bits screws

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I'm kicking my ass, do you mind?

Sometimes I wish that I could kick my own ass.

A long time ago, in a far away galaxy, I installed slackware on a hard drive. The thought was that I could use this drive as an emergency drive to power-on and back-up dying systems or resurect dead ones. So clever I was that I setup a very generic kernel to ensure that it would boot on any system. So clever I was that I changed the boot image from vmlinuz to vmlinuz.old and then changed lilo.conf to boot from vmlinuz.old. It took me five kernel compiles to catch on… Hint, the Linux 2.6 ‘make install’ copies bzImage to vmlinuz

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Offline?! Burning?!

Offline. what?! My server, offline?!

“No way” I said to my self while traveling in France when trying to log into my server. There’s no way a fully redundant server has failed. UPS, dual CPU, hardware RAID5 with hot-spare. Down. Out. Not responding.

Thanks to Brian, I was finally able to move my file server out of the rack to a location where I could work on it. After a few minutes of debugging, I finally figured out why the server had failed:

Yes, I know that it is 2008. Yes, I know that ISA is extinct. I love old hardware. I like to recycle old things and bring them

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Who knows what tomorrow will bring

Thanks to a friend, I’ve been introduced to variety of new music recently. Stuff that I’d have a hard time finding on my own.

One of the artists that I really like is RJD2. He started mixing in Columbus, OH, and then joined a rap group called MHz. Although RJD2’s genre is listed as Hip-hop, he has an eclectic release of music. Soul, Techno, hip-hop, house… Most people who have watched TV have heard his music as the the theme to a commercial or two.

My favorite song is “Smoke and Mirrors” because there is an old sample of a rhythm and blues song. It sounds almost like Jimmy Hendrix

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Visual Studio 2005

After working with Visual Studio 2005 since before its release, I have compiled a list of “issues” I have encountered with it, and in some places compare these “features” to that of other similar products I’ve used. Note that some of these may have been fixed/changed in Service Pack 1 (but all are valid in its final release, not beta, version), as I have been compiling this list over a long period of time.

Intellisense requires too much CPU. Prior versions were fast and efficient. Eclipse is likewise very fast too on the same machine. I also frequently see “Please wait while the documentation cache is being generated” in the

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