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Comment: Re:It is a MakerBot after all (Score 1) 185

by ahfoo (#44183659) Attached to: Breaking Up With MakerBot

I'm in the tropics as well and I don't use AC because I'm on the coast and it's not too warm but I had the same humidity issue that I had been living with for years. People had suggested getting a dehumidifier but I assumed they used almost as much current as an AC. But this year I had family coming to visit from the States and I looked more closely at dehumidifiers and found that they weren't as inefficient as I thought. I bought a Panasonic rated at 200watts and modified it with a hose that runs the water outside. It extracts a surprising amount of water from the interior air when it is warm and humid like say five gallons or twenty liters a day.

I run that water outside into a bucket and then pump it into a mist sprinkler head on a timer powered by an aquarium pump to cool the yard and it has a dramatic effect on the overall climate of the house while using fairly minimal amounts of electricity. If you're in a coastal tropical area it's a nice way to go.

Comment: An arm is what I'd be hoping for. (Score 1) 24

by ahfoo (#43765085) Attached to: Arduino Branches Out, With a Plug-and-Program Robot

I have a robot vacuum cleaner and it's more than a toy. I really cherish the thing. It's great. This is indeed a bit close to the specs of a robot vacuum cleaner. Now of course it's potentially much more than that. I certainly get that. That's nice but . . .

The other day I was looking around at Aliexpress. As a matter of fact, I was buying a ten pack of ATMega328s in the DIP 28 format since I'm an Arduino lover. As I was checking out I got one of those ads at that bottom saying: Other people who bought ten packs of ATMega328s also bought

And there was a totally bad ass looking robot hand. The thing looked like a piece of art. It was a human hand made of stainless steel wire basically. A pretty thing where every little finger moved independently. Sexy little thing. I hadn't thought to search for off-the-shelf robot hands.

But I was inspired to do so and I was quite impressed. There was a whole range of six degree of freedom hands for less than two hundred bucks. The down side was the controllers didn't look all that friendly. I'm just a hobbyist but I know from my investigations that industrial robots tend to use these things called teaching pendants which are basically like macro recorders that just take the input from the servos and record it so that you can rough-in a certain manipulation and then starting with that you can go to and editor and fine tune the functionality. So having an open and friendly user community for something like that would be amazing.

I'd hope to see Arduino putting something like that to work although I can imagine that perhaps a teaching pendant application might involve something a bit more beefy like the BeagleBone Black or RasPi.

An application like an open source robot hand massage would be the beginning of something interesting.

Comment: Is steel expensive in China though? (Score 1) 139

by ahfoo (#43022779) Attached to: New Technology Produces Cheaper Tantalum and Titanium

Now I realize retail and wholesale are two different worlds but here in Taiwan retail I just bought 36 meters of 1" diameter 18 guage steel square tubing for about US$72.00. I thought that was quite cheap actually. 36 meters, that's over a hundred feet so about seventy cents a linear foot.

I was just driving down south over the Chinese New Year and I saw nothing but truck after truck carrying steel rolls.

I suspect steel has gotten expensive in some countries and not so much in others. Copper is the same way. Chinese copper is a heck of a lot cheaper than copper in the US. I was going to make some copper fittings and then I priced them from China and I could get them pre-made and shipped for cheaper than I could buy the raw metal in the States.

Comment: Dessicant Wheels, LiBr Absorption Chiller (Score 1) 422

by ahfoo (#41520815) Attached to: Ask Slashdot: What Would You Include In a New Building?

Dessicant wheels can be a low cost method of controlling humidity. Certain specialized dessicant wheels for clean room applications can be expensive but you don't need to use those types. Dessicant wheels can actually be very cheap if you plan around them when you design the new facilities. Reducing humidity makes the environment more comfortable but is also way better for electronic and mechanical equipment. It also prevents the growth of mold and other microorganisms.

Part of making dessicant wheels cheap is having a cheap source of heat energy to recharge the dessicant wheels when they turn to the outside environment. Luckily, you can use the latest generation of extremely low cost solar thermal vacuum tubes coupled to copper heat pipes to capture and store solar thermal energy at low costs. An 1800mm x 58mm vacuum tube heat pipe combo can capture approximately 80 watts of solar thermal energy per tube under optimum conditions and yet they cost only around ten dollars a tube when purchased in lots of 100 from Chinese manufacturers that crank them out by the hundreds of thousands. Even compared to today's low-cost solar photovoltaic that's an order of magnitude lower costs on a per watt basis.

You can then apply the heat from those pipes that you store in say a 10,000 gallon tank of water to fire a Lithium Bromide chiller to chill the entire facility. Remember, the ongoing fuel costs for this system will be zero and it had integrated storage independent of external utilities.

The general idea is to think in terms of direct applications of thermal storage rather than conversion to electricity.

Comment: The Z-80 CPU is still in many new products. (Score 1) 143

by ahfoo (#39759921) Attached to: 30 Years of the TRS-80 Model 100

Retro video game fans know this CPU well but it's still being sold in brand new products with new software being targeted for it.

I use a Z-80 every day in my so-called car MP4 player. These are cheap car FM transmitter players that are easily found on eBay for a measly six bucks. They're so cheap I hand them out at Christmas to anyone who wants one.

The knock off second generation iPod Nanos are based on the same thing. Those are like twenty bucks because they have the battery and a bit more hassle than they're worth but what is cool in a geeky sort of way about these two products together is that since they both use the Z-80, they both use the same video compression format. It does work to play videos and the open source package works fine on Linux.

Comment: Granularity and electronic currencies. (Score 1) 298

by ahfoo (#39656043) Attached to: Canadian Mint To Create Digital Currency

I'm so pleased to see this announcement and I would like to address those individuals here at Slashdot who are familiar with software development and ask you to consider something about electronic currencies that has long been in my mind and that I've posted about here and in other places before. I'd like to draw everyone's attention to the notion of granularity.

One of the cool things about being a software developer and one of the things that makes it so addictive to those who get into it is the fact that a software developer is like a god in relationship to the program under development. This is not unique to programming, writers of other sorts share this ability to simply create things out of thin air but in software development it is a fundamental skill. You declare a variable and it exists. That's all there is to it, you imagine it into existence.

So, sometimes when you're working on developing a program and you might find that the variables you've previously defined are insufficient for some task and you need to create new ones. This isn't a problem in software, you just make it happen. And you may find that there are places in your code that can be optimized with finer control so you make the finer degree of control by simply creating it. That's what I am referring to as granularity.

Being able to optimize granularity is a very cool thing. Now imagine applying the topic of granularity as it exists in software development to the economy.

There is no such thing as a free market in our world today. What we've got in the Anglo-American system is not a free market but a market with very coarse controls. It's not the case that it is or every will be or ever has been completely free. It has controls and those controls are what is called monetary policy. Basically, the government by being the largest borrower in the market can set interest rates. There's that and then there's spending and taxes and otherwise the government is pretty much out of the economic equation. The lack of granularity means that governments have very little control over the economy once the interest rates go down to zero.

An electronic currency opens up the possibility of creating a whole new level of control. Instead of all currency being exactly the same it would be possible to create individual units of currency with different depreciation or appreciation rates. The currency itself could become not unlike the bond market.

Now why on earth would anyone ever take payment in a currency that was pre-destined to depreciate? There would be no incentive to use it right? Well, there would if it was being offered as a form of social welfare. That is, in order to make a welfare state sustainable you would avoid the classic problem of creating inflation by making payment in a form of currency that had to be spent or else it would lose its value. The money would either be used quickly to stimulate the economy in times of economic hardship or it would disappear from the ledger completely.

I've mentioned this idea before and I realize it's a hard one for many people to get their heads around but I think it's important to remember one thing about electronic currency.

Adam Smith, Karl Marx, John Keynes no economic theorist could have imagined the role of electronics and digital communications today. It simply didn't exist. So when we apply the same old 19th century ideas to our current situation we're really selling ourselves short. We are in a new era. We've been here for a several decades now and yet the predominant attitude is one of denial. It's as if we collectively imagine that we're all going to go back to the way things used to be some day like Dorthy waking up back in Kansas but I think it's time to face the fact that the world can change for the better.

We simply need to make it so.

Comment: I want to play game, how to? (Score 1) 165

by ahfoo (#38559616) Attached to: MAME Running In Chrome

There's all this bickering in this thread along the usual lines of programming nuances and security blah blah blah which is fine and good but how about for the people who just want to see how this thing does with a few of their favorite ROMs?

Anybody actually have this installed (preferably on a GNU-Linux installation) and care to point out how they went about it?

Comment: They killed ath.cx for free users. (Score 3, Interesting) 223

by ahfoo (#38406790) Attached to: DynDNS Cuts Back Free DNS Options

That was what pissed me off. But yeah, this is old news.

Hell I think dynamic DNS should be a basic function of the net. That's how it was supposed to go. What is this Facebook shit. We're supposed to have our own servers. Indeed, back in the day it was actually originally set up where you directly applied for a class C IP range. That was a perfectly reasonable premise. It's interesting how far we've gotten away from that rather simple concept.

Comment: Re:I stopped reading the responses after... (Score 3, Informative) 920

by ahfoo (#37892262) Attached to: The White House Responds To We the People Petition

You can indeed die from heroin withdrawl. For a heavy user going cold turkey it's normal to experience extremely elevated blood pressure that can directly result in death especially when there are aggravating factors which is common in people living off a substance that can only be obtained in a black market economy of questionable purity injecting the drug with recycled syringes. You bet they can have complicating conditions before they go cold turkey under those circumstances. Circulatory problems are not a rare thing for junkies by any means. Totally collapsed veins are not unusual at all. When you couple those circumstances with an intense extended period of extremely elevated blood pressure it can result in death.

Having said that, the far more common cause of death for a heroin user going cold turkey is not a direct result of the withdrawl symptoms but an overdose in an effort to control the symptoms of withdrawl. That's pretty much the classic OD scenario. Saying that you can't die from quitting heroin seems to be a bit overly simplistic given that fact.

Comment: How about using a Controller Area Network? (Score 1) 409

by ahfoo (#29882225) Attached to: What is the Current State of Home Automation?

This is a bus that is growing rapidly in the automotive industry and is also popular in vending machines. There's an element of structure built into the network level to enhance safety as it's an automotive standard.

There has been an open source home automation system based on it for several years.

Yeah, here it is:
http://caraca.sourceforge.net/

Comment: so blind as to over look an easy 10's of millons (Score 1) 476

by ahfoo (#26425989) Attached to: How Microsoft Beats GNU/Linux In Schools

Tens of millions? It's more than that by far. The financial relationship between school districts and Microsoft is immense.

The very notion on free software is under constant attack day in and day out in the school precisely because the school administrations are already so bought out.

The only reason Microsoft even exists is because of their insistence that everybody owes them something.

How does Microsoft beat Linux in schools? The answers are vast. But what is partly missing in the analysis is the fact that the education "market" is not isolated to the United States. These are global issues in the here and now.

Heisenberg may have been here.

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