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2019-01-20, 21:15   #397
xilman
Bamboozled!

"𒉺𒌌𒇷𒆷𒀭"
May 2003
Down not across

10,949 Posts

Quote:
 Originally Posted by chalsall "I before E, except after C." Weird....
The rule is "... when the sound is ee." Otherwise words like height and weight aren't covered.

However, consider the fully grammatical sentence: "Sheila, seize weird Keith!" which consists entirely of exceptions.

 2019-02-06, 00:49 #398 jvang veganjoy     "Joey" Nov 2015 Middle of Nowhere,AR 22·3·37 Posts http://time.com/5475668/raw-cookie-dough/ https://www.washingtonpost.com/healt...=.a4ccc5f61ba7 https://www.cdc.gov/features/no-raw-dough/index.html https://www.cnn.com/2017/11/24/healt...oli/index.html https://www.cookinglight.com/eating-...t-cookie-dough So raw cookie dough is scary. But it's not just eggs anymore; raw flour has been recently shown to potentially carry E. Coli. It gets contaminated in the processing/packaging process, and not treated afterwards because the flour is intended to be cooked. Fortunately, there is a way to get around these spooky bacteria. For flour, you can bake/toast it at 350 degrees Fahrenheit for 5 minutes, if you don't plan on cooking it. Some people do this even if they are cooking the cookies/whatever, since it changes the taste of the dough slightly. For eggs, you can buy pasteurized eggs. A particular brand, Safest Choice, is a common brand of these, but they're not available everywhere. You can pasteurize normal eggs yourself, by cooking them in 140 degrees Fahrenheit water for 5 minutes. If it goes over 142 degrees, it might mess with the consistency of the eggs, and under 140 will make the process less effective. The homemade process is still not 100% optimal, but it's much better than nothing (anyone with a compromised/weak immune system shouldn't eat raw eggs, pasteurized or not). Another alternative is pasteurized egg whites, which are normally used in dressings and other recipes that call for raw eggs.
 2019-02-06, 03:12 #399 nomead     "Sam Laur" Dec 2018 Turku, Finland 13D16 Posts Salmonella is really not a problem here in Finland. For decades already, we have had a screening program in place to detect and isolate even the very few cases that may occur. Also poultry vaccinations are becoming more commonplace, which helps a lot in keeping the production system clean. This is not an EU-level thing, actually I only know that Sweden and Denmark also have such screening programs and are equally efficient. Some EU countries screen for only some strains of salmonella, and some others do nothing. For this reason, it is only allowed to import intact eggs from Denmark or Sweden. Processed product (without shell, egg powder, etc) must be industrially pasteurized because you really can't know. And as you may know, intact really means that here, even unwashed. This preserves the outermost layer (cuticle?) of the egg shell and prevents any bacteria on the outside from getting in. So if there is salmonella in the egg, it must come from the chicken that laid the egg, not contamination afterwards. Of course this screening costs something, but it is not a problem with the right priorities. Food safety is number one, not agro-industry profit. And I know it's not the individual farmers making any profit, it's the big \$ industry. E. coli is a different thing, then. It can survive in the ground for months, and even in frozen ground, actually for a longer period than in warmer conditions. Fortunately not all strains are dangerous. But it can't be eliminated from the environment. Only product testing and screening, and hygienic processing practices really help. And even then some cases pop up now and then. Locally, a tourist attraction "old time farm" was selling fresh raw (unpasteurized) milk. Everything went fine for years, and then suddenly a group of people got really sick. They found EHEC in the milk and in the cows, and also in the ground, and in the end, that farm had to shut down any dairy related activities. Salad also often causes problems. Probably through irrigating the plants with contaminated water. Though I haven't seen any news about wheat flour or raw dough being declared dangerous here, I've seen the news about the US cases when it was new. There was a brief scare, but the local food safety authority declared that although still possible, their monitoring data showed that it is not a problem here. But yeah, maybe it's better to avoid it anyway.
 2019-02-14, 02:51 #400 jvang veganjoy     "Joey" Nov 2015 Middle of Nowhere,AR 22·3·37 Posts My dad wants to make a "little man computer" (some sort of demonstrative model for teaching how computers work?) using a ternary number system, in particular balanced ternary, where the digits are -1, 0, and 1. I already have trouble figuring out how binary works, so I'm not sure how this is going to work. From what I've read and understood, the little man computer uses numerical codes for programming, with each 3 digit set of numbers being an instruction. And it refers to memory locations as mailbox numbers? How would you go about "making" this computer? Would t be as simple as writing a program that takes in these sorts of inputs or whatever?
2019-02-14, 08:37   #401
xilman
Bamboozled!

"𒉺𒌌𒇷𒆷𒀭"
May 2003
Down not across

10,949 Posts

Quote:
 Originally Posted by jvang My dad wants to make a "little man computer" (some sort of demonstrative model for teaching how computers work?) using a ternary number system, in particular balanced ternary, where the digits are -1, 0, and 1. I already have trouble figuring out how binary works, so I'm not sure how this is going to work. From what I've read and understood, the little man computer uses numerical codes for programming, with each 3 digit set of numbers being an instruction. And it refers to memory locations as mailbox numbers? How would you go about "making" this computer? Would t be as simple as writing a program that takes in these sorts of inputs or whatever?
That would work. It's called emulation.

A much bigger task would to build a physical device with the properties you describe. Charles Babbage designed a mechanical decimal computer over 150 years ago but never built one. Electronic ternary computers could be built but, again, it would be a major task.

2019-02-18, 02:16   #402
jvang
veganjoy

"Joey"
Nov 2015
Middle of Nowhere,AR

22·3·37 Posts

Quote:
 Originally Posted by xilman That would work. It's called emulation. A much bigger task would to build a physical device with the properties you describe.
Other than one existing physically and one not, what's the difference between a real computer and an emulated one? And, as a simple example, does a program that prints 1's repeatedly emulate a computer that prints 1's upon startup?

My dad has narrowed down what he thinks should be emulated:
• Uses balanced ternary instead of binary
• Fulfills the basic functions outlined in the Little Man Computer model
• Uses the Harvard architecture instead of von Neumann
• Has its own (small amount, probably several kilobytes) of memory, storage, etc.

We'll be working in Python, which means everything is going to be pretty slow.

It seems that there aren't many tutorials for emulating a system that hasn't already existed. There have only been a handful of ternary computers ever made: one in the 1800's, made entirely of wood; two Russian-built ones in the 1960's/1970's; and a ternary microprocessor built in the last couple of years. I've read that emulating something starts with using software to recreate the original hardware; does that mean that we should start by using Python to recreate the functions of a preexisting ternary computer?

As far as the computer architecture, I think that the main difference between von Neumann and Harvard is that instructions and data are stored in the same memory for von Neumann, whereas the Harvard architecture allows instructions and data to be read at the same time because they are stored in separate locations. I haven't figured out much about a "modified" Harvard architecture, which is more common than a "pure" Harvard architecture. Another big thing that I read was that von Neumann systems need a cache to run faster than the main memory, while a Harvard system doesn't need one.

2019-02-18, 02:55   #403
chalsall
If I May

"Chris Halsall"
Sep 2002

23×17×73 Posts

Quote:
 Originally Posted by jvang Another big thing that I read was that von Neumann systems need a cache to run faster than the main memory, while a Harvard system doesn't need one.
You might be going a little too deep here.

Seriously. Do you have an infinite amount of memory?

Have you tried using Oracle's VirtualBox?

If not, you might want to try it.

Kinda cool....

2019-02-18, 15:31   #404
Xyzzy

Aug 2002

24·3·173 Posts

Quote:
 Originally Posted by jvang And, as a simple example, does a program that prints 1's repeatedly emulate a computer that prints 1's upon startup?
Isn't that just emulating the output instead of emulating the computer itself?

2019-02-18, 20:42   #405
xilman
Bamboozled!

"𒉺𒌌𒇷𒆷𒀭"
May 2003
Down not across

10,949 Posts

Quote:
 Originally Posted by Xyzzy Isn't that just emulating the output instead of emulating the computer itself?
How do you tell the difference?

This is not a fatuous comment but a hint to a profound philosophical question.

Paraphrased, if it walks like a duck, quacks like a duck, and so on, in what way is it not a duck?

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