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| I finished my paper for this week. Here it is in the form it will be handed in. I have to wait until Friday so it gets handed in with the rest of the papers.
Scott
Fisher
Assignment
6
Should Software Be
Used in Safety-Critical Systems?
The
question has arisen as to whether or not software should be used in
safety-critical systems. To answer this
question, we must first answer the question what is a safety-critical system?
According
to Wikipedia, a safety-critical system, or life-critical system as they call
it, is a system that is designed to lose less than one life per billion (10^9
[1,000,000,000]) hours of operation. I
believe that a more simple definition of a safety-critical system exists, and
that is that it is a system in which safety is critical, or very
important. Therefore, we know that a
safety-critical system is one in which it would be pretty bad if the system
messed up.
Now that we
have an in-depth knowledge of what a life-critical system is, we can address
our first question. Should software be
used on a safety(life)-critical system?
I don’t believe that it should be and here is why. Software, no matter how well tested, will
always contain errors, unless it is tested to the point where all errors are
definitely found. Even then, more errors
will probably arise when some user enters weird input that the programmers
couldn’t have foreseen.
Wikipedia
offered an example of how a safety-critical life system can fail and what the
consequences of such a failure are. They
showed a picture of an airplane, a fighter jet but I am not sure what kind,
maybe an F-18 Hornet, that crashed due to system failure. Because of a programming error, somebody died
in a plane crash. The pilot lived, but
he got hurt and very well could have died.
I am not sure if the fighter failed because of a software issue, but it
probably did. This is a clear example of
what can happen due to small, unforeseen errors in software. I think that this clearly shows that software
should indeed not be used in safety/life-critical systems.
Another
reason that software should not be used in a life-safety-critical system is
because it can’t be guaranteed not to fail.
Hardware can be tested to make sure it meets the criteria of the safety
of a life-critical system. Methods exist
to ensure that hardware will be guaranteed to fail less than once in one
billion hours. This means that we can be
positive that the hardware will almost never fail, probably. Do methods exist to prove that the software
will fail at the same rate? I don’t
know, probably not. I’m willing to bet,
though not money since the University is sucking me dry of it, that no matter
how many times we test the software, we can’t be completely sure that the
software won’t fail. More bugs in the
software will probably definitely be possibly found.
Another
clear example of why software shouldn’t be used in a safety-critical system is
in the book Lord of the Flies by William Golding. In this story, a plane crashes on an island
leaving a group of boys stranded there.
In fact, a second airplane crashed later, and the pilot parachuted onto
the island, dead. Later, because of
being stranded on the island, and because of the stress from the dead rotting
carcass they found on the top of the island (the parachutist), the boys went
nuts and started killing each other.
This is what can happen if a safety-critical system fails more than once
in a billion hours, and software makes it more likely that this may happen.
In
conclusion, it is definitely not a good idea to use software in a system
critical for life safety. It is a
proven, yet mind numbingly obvious fact that software makes airplanes
crash. Even when we think that we have
all the bugs worked out, some moron working reception at the airport will enter
“San Diego” as a passenger’s telephone number (I’ve seen crap like that too
many times) and make a plane crash on a desert island forcing the stranded
people to revert to cannibalism just hours before they are rescued by a passing
cruise ship. I sure wouldn’t want to eat
that annoying kid that was kicking my seat the entire flight, just to be rescued
shortly afterwards (then again…). Imagine
the guilt. I also feel sorry for the
crew and passengers on the boat who had to see these acts of savagery, and are
no doubt scarred for life because of having seen them. Let’s stick to hardware for safety-critical
systems. | | |
| I have a new game I'm playing in one of my classes. All of you can enjoy the game with me.
One of my classes this semester is Social Implications of Computers. This is considered the Computer Science capstone course and it covers ethical issues involving computers. I noticed right away that our teacher doesn't really seem to care what we do in the class. Every week, he has us submit a 2 page paper. These papers were originally single spaced, but after some bitching from yours truly, we were allowed to use 1.5 spacing. After turning in 4 of these papers, I was not convinced that they were being read at all. There are about 40 people in this class, and I'm sure the teacher or grader would not want to read 40 2 page papers every single week. I had gotten 15/15 on all 4 papers and decided to test my theory. I am going to see how much rambling, incoherent bullshit I can turn in before I get docked points.
For last week's paper, assignment 5, we were to read 4 articles out of the computing magazine Communications of the ACM. The articles were all about spyware on computers. I read my 4 articles and started writing. I divided the paper up into 4 paragraphs of a half page each, one paragraph for each article. The second paragraph of my paper was very sarcastic because I thought that article was stupid. I didn't put any outrageous sentences in here and still summarized the article.
In the third paragraph, I decided to see if the papers were being read. In the middle of the paragraph, I put in the following sentence: "The banana industry is almost entirely
controlled by three large fruit companies: Chiquita, Dole, and Del Monte." The paragraph was about computers infected with spyware.
I got a 15/15 on this assignment. I'm just finishing up writing the paper for this week. The topic this week is "Should software be used in safety-critical systems?" As soon as I submit my paper, I'll post it on here for you to read. I promise it will be much more entertaining than this last one.
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| I wonder if anybody will still read this, it has been a while.
On Valentine's Day, I was in class reading the Spectrum. They had an article about singles night at Playmaker's. At this shindig, singles were supposed to wear red and couples black so that people could easily tell who they should be hitting on. Plus they played a little game where everybody got a ticket with a number on it, and if you could find the person of the opposite gender with your number, you got a free drink.
I thought this sounded interesting and convinced Dave and Karl to go with me. Karl was going to meet me and Dave there, so Dave and I got dressed up in our red shirts and headed for the party.
We got there and the parking lot was packed. There were no spots to be had, so I ended up parking on the street about a block and a half away from the entrance. It was very cold that night, but we didn't want our jackets to collect that smokey smell that bars are known for, so we dropped them in the car and sprinted to the door. I got inside and CRAP, my wallet was in my coat. Dave waited in the entrance as I sprinted back to my car again to get my wallet, and then sprinted back the entrance. I could not feel my upper body at this point. Now with money and proof of my age, we walked up to the girl checking IDs.
I think all of you have seen me lately. If you haven't, I look different than I did when I was 17 and my license picture was taken. Different to the tune of about 30 pounds and a completely different hair style. The lady took my ID and looked at the picture. She then gave me a funny look like I was obviously trying to use a fake ID. I saw her do this and I laughed. Not knowing what to say at the time (probably from the shock of the cold) I said, "It was my birthday 2 days ago." I knew this wasn't the issue, but don't ask why I said it. She finally gave me my ID and let me in.
I walk inside and take a look around. My first thought is, "Ok, look for red. This place... SUCKS! How is almost EVERYBODY taken? Oh man, she is pretty AND wearing red. What the heck, it looks like she is with that guy." We head to the main table and grab our tickets, then go grab some beer from the bar ($1 taps, sounding better already). We start the hunt for our free drink.
Dave and I walk inside the House of Rock and he spots some of his buddies sitting at a table. We go over there and Dave is talking to them. I can't remember what I was doing, let's say I spaced out. I was startled back to reality when Dave turned to me really quickly.
"He said that you are supposed to wear black if you are single."
"No, the Spectrum said red for single, black for couples."
"Yeah, he said he called and the Spectrum had it wrong."
Oh shit. Dave and I look like a couple.
I walk over to a table full of girls, the most attractive one wearing red, and looked at one of the girls in black.
"Let me get this straight, you are wearing black cause you are single?"
"Yeah."
"Shit. The NDSU paper SUCKS. This is a little embarrassing. Hey, what is your number?"
Our numbers didn't match. None of the 4 girls at that table had numbers that matched mine or Dave's.
"Hey Dave we gotta go change and come back."
We chugged our beers and headed for the door. I told the lady that checked our IDs our situation. I figured I could since we had been there for about 5 minutes.
She told me, "Who cares? Just go have fun."
"Screw that, I'm changing."
I called Karl and told him to NOT wear red. I caught him before he had left. We sprinted back to the car through the cold.
Dave and I go change and go back to the bar. We sprint back inside this time from a little farther away since I had lost my parking spot. Karl was there waiting for us. I had my ID checked again and she either remember me or thought I looked enough like my picture not to give me a funny look this time.
We headed inside and the lady gave us all tickets again. Now Dave and I have 2 each. Double the chances of a free drink. We start the prowl again.
The rest of the night was pretty uneventful. I drank cheap tap beer and was glad that Dave and I no longer looked like a couple.
The sentence said to me most often that night:
"How did you get two tickets?"
None of us found our match(es) to get our free drink(s).
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| Time for a new photo again.
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