What about the 4000 mph capsule that goes trans-oceanic that the site talks about. I think you'd need to build the transit stations a significant distance away from inhabited areas, because of all the kinetic energy flying around.
If a 10000 lb capsule crashes at into the end of a tunnel at 400 mph because the breaking system failed, that's bad. But if the capsule crashed at 4000 mph, it'd have 100 times more kinetic energy, which could get really ugly for the people outside of the capsule.
The air would have it's own friction to overcome, though. And air flowing through a duct at 500 mph (44000 fpm) for 2000 miles would have a *lot* of pressure to overcome. Wish I had my ductulator, then I could get you folks a number.
This brings about another question, though. There will definitely be *some* air, or other sort of gas, in these tubes. Wouldn't the speed of sound change at very low pressure? I have books that have the answer, but I can't get at them right now.
From reading the article, I didn't envision this system being used for short-distance transport. Rather, I figured on it being used primarily for city-to-city transport. That would be easier to install (on a per-mile basis) than a subway replacement.
Hmmmm? I didn't know there was another release of 'Boondock Saints'. Where can I get the one you speak of? The movie seemed awesome to me as I saw it, but I'd love to see more (just as long as it isn't Willem Dafoe getting naked).
You know, it just struck me that this sounds a bit like the feared 'economy class syndrome' that we've heard about on the news. From the press I've heard, it can happen when a person sits in a chair for a long time without being able to move around much, and a blood clot gets the chance to form in the legs or buttocks. IIRC, the trial lawyers are trying to soak the airlines with lawsuits about this.
In the airplane cases, these people are in their seats for 5-10 hours, in the cases I've heard of. And this guy was sitting in that chair for 86 hours. Granted, he might have gotten up to go to the restroom a few times, but that could still cause problems. From what I know, your body needs to lay down every once in a while, if only to redistribute bodily fluids to where they ought to be.
Thanks for the input. A guy at the LUG here in Jax also mentioned that learning comes from breaking things, so I guess I'll just charge in there. It is nice to know that I can reformat my hard drive and start over whenever I want to, so I'll probably be doing that a few times with SUSE, and then we'll see what happens with LFS.
The longshoremen aren't getting paid 'very little'. These guys are getting $100k on average, with the clerks getting $120k average.
When the left looks at these situations, they only look at the current union members who are holding the jobs right now, they never stop to think of the many capable people who would like to compete for those jobs. If they are willing to do the job for less, I think the employer should be free to hire them.
Ok, I've been intrigued with LFS for some time because of the whole learning aspect, but I'm sure I'm not ready. What I'm wondering is what should I do to get myself to the point of being ready to touch LFS?
Background: I have Suse Pro 8.0 on a separate switched HD, and I am a *nix newbie. I got it installed ok, and to be honest, I haven't touched it in about 5 months (I am studying for my professional engineering exam in mechanical engineering...once I get a pass I'll have time for Linux again...until then my wife stresses every time she even sees me checking a few web sites when I could be studying, much less spending hours on end learning Linux). My plan is to lock down my Suse distro as much as possible once I'm out of this test, using the Max. Linux Security, 2nd ed. book. I also plan to make an old 486 computer into a hardware firewall, with one of the firewall optimized distros. I started learning emacs before I got pulled away, and I plan to become as proficient as possible with that.
Beyond these things, what else should I do to learn? My job is not in IT (I design HVAC systems), so there aren't really any on the job tasks to use Linux for. Any pointers would be appreciated.
All of those things are great activities, but as a proud band geek, I must say that my time in school was made much richer by my experiences in band (in high school and college). I think that the drama club/chorus/yearbook folks could probably say the same thing. These experiences, IMHO, can't be duplicated by home school. I think for the elementary age stuff (ages 5-12 or so, for non-US people), there are plenty of groups away from school, as you have mentioned. Once you get to the high school age, though, the things tend to be more involved, ie., they almost require the sponsorship of a high school. I guess you could keep doing Boy Scouts, but that doesn't involve guard girls in spandex on the band bus (dang!!!! so many missed opportunities-if only I could've traded some of my book smarts for intelligence of a different sort).
As far as how home schooled kids turn out, I know a pair of brothers that turned out to be the stereotypical weird home schooled kids, except not nearly as smart, and then I know another guy that turned out to be of above average intelligence and very good social skills.
In Georgia a few years ago, they came up with a program that provided scholarships to all graduating high school students in the state with "B" averages (it could've been guaranteed admission, but I'm almost positive it was the HOPE scholarship). Of course, as anyone on/. would've guessed, the number of "B" averages increased by leaps and bounds in the years that followed.
Speaking of true curves, I had a Heats teacher in the Mechanical Engineering Dept. at Univ. of Fla. who truly graded on the curve. I am forgetting his name, but he was an older chinese guy, and he was a lot of fun. He would do a sample distribution of the grades on a graph at the beginning of the semester, and then divide the graph into five regions. Then he would point at the different grade groupings, announcing that the first group was "A", the second was "B", etc., and the last group was "Sacrifice". The accent really added a lot to it...I guess you'd have had to been there.
As an engineer who designs air-conditioning systems all day long, I can safely say that architects make *our* lives difficult by wanting such huge windows, high ceilings, etc.
They never want to give us enough mechanical space, which can make life hard on the maintenance folk, since we have to wedge stuff into places that make it hard to pull coils for cleaning, replace filters, etc. Let's not even talk about architects who want a lay-in ceiling at 9', and have bottom of structure above at 10'3", and expect us to put our ducts between the two. Our ducts aren't the only thing that has to go up there, there are also lights that poke up (typically 6"), fire sprinkler piping, etc. Of course, the contractors are upset with our design when they have trouble fitting stuff.
Large windows just allow lots of heat into buildings. Even if owners were to spring for high-efficiency, insulated windows, they let in five times as much heat as a decently insulated wall, without even accounting for the solar energy they let in (and owners most often want the cheapest single pane windows they can get). I feel like architects nowadays use glass almost as a crutch for making a building look nice. I recently worked on the conversion of a 90-year-old school building into lofts for residential use. Those old school buildings have these huge (20' long x 8' high) windows, single pane, not well sealed. This added significant air conditioning to each apartment, and even if I match the calculated heat gain with my air conditioning capacity, someone next to the window will be warm, just because there will be a thermal layer.
High ceilings cause thermal stratification. This isn't normally a problem in the summer, as the cool air from the air conditioner falls towards the floor, where people want it anyway. In the winter, however, the hot air rises, and you've got to do quite a bit of heating before the warm air layer gets down to person level (unless you have hot water heating under the floors, which I'd like to do in my house when I buy one, but I live in the south, and they don't do much of that down here.)
On the previously mentioned lofts project, the architect did a few apartments where there had previously been an auditorium. Upon walking into the apt, you stood in the living room and could see all the way up to the main ceiling 20' above you. The apartment was one large space, with the back of the apartment being divided into split levels, with the kitchen on the main floor and the bedroom on the upper level. So you could walk from the living room with the extremely high ceiling, directly back into the kitchen with the low ceiling (b/c of the bedroom above it), and then climb stairs to the bedroom, which shared a ceiling with the living room. Standing in the bedroom, you had a bannister that you could stand at and look down into the living room. Also, as an artifact of the history as an auditorium, each apartment had a double glass door centered in a 15' wide x 18' high window. The window serves the dual tasks of letting in/out lots of heat, while also making it easy for any passerby to see directly into the entire apartment (unless you have your 18' high venetian blinds closed). In fact, even if you have blinds, you'd better hope your not backlit when you're doing anything in the apartment. Regarding heating and cooling, the cooling season should produce some stratification, and it'll be somewhat difficult to cool that bedroom. In heating season, though, it'll bake the bedroom and freeze the living room. I warned the architect, but he persisted.
Well, that's just a little sample from an HVAC engineers perspective. Sorry it's so long.
1 Ton of air conditioning equals 12000 Btuh (British thermal units per hour). 3.418 Btuh equals 1 Watt. So 1 ton equals approximately 3510 Watts of heat (or cooling, whichever you prefer).
The Btuh thing is a bit confusing to some, because most people only say "btu", but they can mean "Btuh", as in rate of heating or cooling, or they can actually mean "Btu", which means an actual amount of heat or energy (as in a canister of gas for your barbeque grill). Hope this clears it up for you. BTW, I know this B/C I design air conditioning systems.
Come on, this "Can't we all just get along" stuff just doesn't work. It is human nature to want to take what someone else has, and I've seen nothing to indicate that people can change human nature. Communists believed that people (especially children) could be educated out of selfish human nature, but that proved wrong.
I see these bumper stickers that say, "You cannot simultaneously prepare for and prevent war.", and that is garbage. As long as there are multiple groups with interests on this earth, the unilateral disarmament of one will only lead to aggression by another group. For that reason, I say that the *only* way to prevent war is to prepare for it. You need to make it extremely painful for anyone else to bother you. The US did this in the cold war, and the Soviets decided they'd just as soon leave us alone. I am all for having a peaceful world, but provided that we're all humans, and at least some of us will be armed, the only way to achieve peace is through deterrence.
Ok, as has been mentioned, this was tried after the French Revolution (and failed, of course). The interesting part is that, for a while, all watches were, by law, required to show decimal time. The watchmakers, though, couldn't make any money selling decimal time watches, so they made the watches cross-compatible. The watch had to show the whole day, as opposed to half a day, since there was no longer an am set of hours and a pm set of hours. So they used one hour hand, but showed both hour scales on the watch. For minutes, however, they needed two hands, with two different scales.
A horologist friend has one of these watches, and a link to a picture is below. We were working on a project to make a clock tower on the Univ. of Fla. campus with, essentially, four clock faces from 300-400 years ago that few people know about (one face for each side). BTW, converting the one revolution per hour signal from an old clock mechanism to output decimal time on a clock face with mechanical gearing is a mess.
Here's the link for the site.
http://www.ce.ufl.edu/%7Echiep/
This takes you to the clock tower project site. Click the 'Dials' link on the left hand side, and then click on 'Revolutionary or Metric Dial' on the page it takes you to.
Good point. At the time that I spoke to him about the computers, I was under the impression that he'd only purchased two, and I was figuring that the problem could be mostly resolved by going to a different supplier for the other computers. As it was, he sent the first computer back for immediate repairs because of some problem, and the second computer is having problems in ACAD 14. It was later that I found out that he had a stack of eight more of these things stacked elsewhere. Oh well. As an additional point, he selected these computers based upon the advice of the guy that runs the small computer consulting business that does our systems administration.
I work at a small engineering firm. The boss' son, who will be taking over in the next couple of years, has a CS & EE degree, and worked at GE & Sandia in majorly geeky stuff, as far as EE and CS goes. I would think that he'd be smart enough to make intelligent computer decisions, but he surprised me recently.
We are looking to upgrade to a newer version of ACAD, and it won't run on Win95 (which most of our 12 or 13 boxes are running). The new version promises to run on Win 98SE or Win XP Pro. So, we are doing a major upgrade in the office, just so all of the computers can make the jump from Win 95 to Win 98SE (I don't know why he won't go to a newer version of Windows). The worst thing is that he just bought a bunch of Compaq Evos, running P4 1.7 GHz, with 128 megs of SDRAM with an Intel 845 chipset (and the obligatory onboard video and sound). That chipset was practically put out by Intel as a joke, because Intel started out matching the P4 exclusively with RDRAM, then everyone yelled for a DDR SDRAM chipset, and then Intel threw out this 845 chipset that only officially supports SDRAM (then 6 months later, they release a mod of that chipset that finally supports DDR SDRAM). The P4 wants high memory bandwith, so you will take a big hit unless you run RDRAM or DDR SDRAM.
It has been bothering me for the past few days that we're going to be stuck with these POS machines for the next few years, and we'll probably have to upgrade machines again when more demanding software needs to be run, and that just means less money into my profit sharing. I explained this whole memory issue to him, after I saw what he'd bought, and his only explanation was that they weren't all *that* slow, and they were cheaper than the pair of Gateways he'd bought a year earlier. I can see how a typical manager type might need to see the well known brand name on the side of each computer to make him feel better, but this guy is a techie. If he would've spent just a little time learning about what is out there right now, we could've gotten set up for around $650 with machines that would have the same CPU's, DDR SDRAM, even Win 98SE, etc., for the same price (around $650, brand name parts, even). Beyond that, who puts anything together nowadays with 128 megs of any sort of RAM, much less someone who is going to run 5 or 6 concurrent sessions of AutoCAD, plus Outlook & Wordperfect? I understand that we don't have the money to be on the edge with our technology, but he could've at least shopped like an educated geek.
I'm not sure if *everyone* needs to know as much as we (techs & geeks) would like for them to know. I've done a lot of reading on economics, and the concept of 'cost of knowledge' really applies here. Earlier this year, the time came for me to build a new computer to replace my 486/120. I spent many many hours reading articles at Toms Hardware, Arstechnica, etc., learning all of the background that I needed to in order to make an optimal decision for a new computer. To get my knowledge, the cost was high, and the benefit (over spending no time learning and getting a Gateway instead) was fairly modest, in terms of the performance bonus I got. But I did things that way, to a great extent, for the knowledge to be gained in the process, and to move me along towards being a proficient Linux geek.
For one of us, growing up around computers and typically enjoying learning about them, the benefit of learning the guts behind everything is worth the cost. But, if you're a senior citizen, death could be stalking at every turn. I don't believe there is much benefit for her in learning anything beyond the bare minimum. That is why there are, and always will be, companies like AOL, Microsoft, Compaq, Dell, etc.
It is true that only a few people who were above the impact floors made it out. This does not mean, however, that we can or even should design buildings to allow people in that situation to make it out alive (as much as we all would've liked to see them make it out).
I'm a mechanical engineer working in the building design industry (HVAC design, though I've done a bit of sprinkler design). Building fire protection systems(firewalls, eggress corridors & stairwells, sprinklers, etc.) are designed around the premise of keeping the fire out of egress paths for long enough that people can safely get out of the building. This typical assumes that you are dealing with a normal fire (not thousands of pounds of fuel/accelerant) and that a massive explosion hasn't just ripped through your building.
From what I know of the WTC case, those planes trashed those egress stairwells so that people from above couldn't use them (does anyone know how the handful of people from the upper floors who did get out managed it?) Regarding the fireproofing coming off of the beams, they still lasted long enough for everyone to get out who had a viable path. When architects put in an egress corridor, I just don't think there is any way that they can start planning for 'What if an airliner hits this building?' or 'What if some nutcase explodes a moving truck-size amfo bomb nearby?'. The costs would be enormous if you were to truly try to make all high-rises events like these survivable, and the benefits would be comparatively small.
Given 9-11, I think there is no chance that passengers will sit idly by and let someone gain control of a plane. However, even if they did, and even if high-rises were somehow hardened, there are many other less-hardened targets, such as stadiums w/ 80,000+ people. That's why killing the people who would harm us makes so much sense.
I know this doesn't address the software engineering concerns, but this quote from the article sort of ticked me off,
"In most engineering fields, Pfleeger says, such disasters trigger industrywide reforms, as the collapse of the World Trade Center seems likely to do for fireproofing in construction."
The fact is, from everything that I've seen and heard, those buildings staying up as long as they did is a *testament* to the fire protection installed in the buildings. I believe they had asbestos covering at least a portion of the metal beams (seems like they had to switch to a different form of insulation at some level, maybe asbestos wasn't allowed anymore?). Regardless, the fact that a building falls down when you run an airliner loaded with lots of jet fuel into it does not speak badly of the engineering practices, and it's sheer stupidity to suggest otherwise. There are lots of reasons to examine fire protection in this country, but 9-11 is not one of them.
I've got a couple of suggestions.
Try "Blind Man's Bluff - The Untold Story of American Submarine Espionage", by Sherry Sontag and Christopher Drew. This book has some incredible stories. The chapter about the search for the sunken U.S. sub 'Scorpion' was one of my favorites. They ended up using a method of statistical guessing, outlined in yet another book called "The Theory of the Optimal Search".
Another book I really enjoyed was "Skunk Works", by Ben Rich. This book, as you've probably guessed, is all about the history of Lockheed's special project division that developed the U-2, the SR-71, Stealth Fighter, and much other interesting stuff. Ben Rich headed the Skunk Works from 1975 until he retired in 1991.
Well, those are two pretty quick reads, and they don't deal with any of the human intelligence stuff, but they have great cold war stories nonetheless.
I had a Thermo professor at Univ. of Florida named Dr. Gater (most engineers who've graduated from UF in the last twenty or so years probably took Thermo I from him). In Thermo I, he wouldn't let students use the graphing type calculators (he might not have even let students use *any* calculators, but it's been a little while, I forget).
When students would whine about his restrictions, he would say something along the lines of, "What about when you're at the urinal, and an engineer at the next urinal over asks about how much sensible cooling you can get from that chiller? You can't use a calculator then." He was (and is) a terrific teacher, even if I dropped Thermo I once, got an F next, then a D+, then, finally a C+. My problem in his class was that I had become accustomed (in other classes) to not going to class (very often, at least), reading the appropriate material, coming to an understanding of the theory by doing a few problems, and then doing pretty well on the tests. Thermodynamics, unfortunately for my GPA, was entirely different (at least under Dr. Gater). You have to do lots of problems in order to truly understand the material, otherwise you're up a creek (and the knowledge is cumulative, so if you got lazy for a few weeks, you were screwed). Thermo II was entirely take home tests (any calculators allowed) and there was no chance to slow down or get lazy since you were always taking a test (you handed on in on Friday, and then he gave you another). I was extremely proud of my B+ (first time around).
On the subject at hand, though, it seems that most people here (especially those with experience as a math tutor, like myself) would agree that students should learn the basic skills without major calculator help. At a certain point (exactly when is up for debate), calculators can become effective learning tools. Most of us also agree that calculators are invaluable for getting the grunt work out of the way once it's second nature to you. Some people have indicated that, on a well designed test, a students math knowledge or ignorance will be exposed, whether he has a nice calculator or not. Unfortunately, it seems that in many, many (I dare say most) classrooms, the tests that are given aren't nearly up to that standard (as evidenced by the sheer ignorance of the people walking into math labs at community colleges around the country, even after they have passed Algebra classes at the college level). The most vocal defenders of calculators in the realms of educators will always point to teachers who are using calculators for truly enlightened teaching, as if they are typical examples, when we all should know that they are not.
Of course, we also can't forget that TI itself is one of the biggest proponents of this movement, and they have a huge financial stake in the matter. When you figure that nearly every high schooler in algebra is buying a $100 calculator, the numbers get pretty significant.
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What about the 4000 mph capsule that goes trans-oceanic that the site talks about. I think you'd need to build the transit stations a significant distance away from inhabited areas, because of all the kinetic energy flying around.
If a 10000 lb capsule crashes at into the end of a tunnel at 400 mph because the breaking system failed, that's bad. But if the capsule crashed at 4000 mph, it'd have 100 times more kinetic energy, which could get really ugly for the people outside of the capsule.
The air would have it's own friction to overcome, though. And air flowing through
a duct at 500 mph (44000 fpm) for 2000 miles
would have a *lot* of pressure to overcome.
Wish I had my ductulator, then I could get you
folks a number.
This brings about another question, though.
There will definitely be *some* air, or other
sort of gas, in these tubes. Wouldn't the speed
of sound change at very low pressure? I have books that have the answer, but I can't get at them right now.
From reading the article, I didn't envision this system being used for short-distance transport. Rather, I figured on it being used primarily for city-to-city transport. That would be easier to install (on a per-mile basis) than a subway replacement.
Hmmmm? I didn't know there was another release of 'Boondock Saints'. Where can I get the one you speak of? The movie seemed awesome to me as I saw it, but I'd love to see more (just as long as it isn't Willem Dafoe getting naked).
You know, it just struck me that this sounds a bit like the feared 'economy class syndrome' that we've heard about on the news. From the press I've heard, it can happen when a person sits in a chair for a long time without being able to move around much, and a blood clot gets the chance to form in the legs or buttocks. IIRC, the trial lawyers are trying to soak the airlines with lawsuits about this.
In the airplane cases, these people are in their seats for 5-10 hours, in the cases I've heard of. And this guy was sitting in that chair for 86 hours. Granted, he might have gotten up to go to the restroom a few times, but that could still cause problems. From what I know, your body needs to lay down every once in a while, if only to redistribute bodily fluids to where they ought to be.
You can get tungsten rings here.
http://www.r8w.com/trewtungstenwo.html
I almost got one for my wedding ring, but ended up buying a titanium ring. The one with the 22 karat gold looks especially nice,
I think.
Thanks for the input. A guy at the LUG here in Jax also mentioned that learning comes from breaking things, so I guess I'll just charge in there. It is nice to know that I can reformat my hard drive and start over whenever I want to, so I'll probably be doing that a few times with SUSE, and then we'll see what happens with LFS.
The longshoremen aren't getting paid 'very little'. These guys are getting $100k on average, with the clerks getting $120k average.
When the left looks at these situations, they only look at the current union members who are holding the jobs right now, they never stop to think of the many capable people who would like to compete for those jobs. If they are willing to do the job for less, I think the employer should be free to hire them.
Ok, I've been intrigued with LFS for some time because of the whole learning aspect, but I'm sure I'm not ready. What I'm wondering is what should I do to get myself to the point of being ready to touch LFS?
Background: I have Suse Pro 8.0 on a separate switched HD, and I am a *nix newbie. I got it installed ok, and to be honest, I haven't touched it in about 5 months (I am studying for my professional engineering exam in mechanical engineering...once I get a pass I'll have time for Linux again...until then my wife stresses every time she even sees me checking a few web sites when I could be studying, much less spending hours on end learning Linux). My plan is to lock down my Suse distro as much as possible once I'm out of this test, using the Max. Linux Security, 2nd ed. book. I also plan to make an old 486 computer into a hardware firewall, with one of the firewall optimized distros. I started learning emacs before I got pulled away, and I plan to become as proficient as possible with that.
Beyond these things, what else should I do to learn? My job is not in IT (I design HVAC systems), so there aren't really any on the job tasks to use Linux for. Any pointers would be appreciated.
All of those things are great activities, but as a proud band geek, I must say that my time in school was made much richer by my experiences in band (in high school and college). I think that the drama club/chorus/yearbook folks could probably say the same thing. These experiences, IMHO, can't be duplicated by home school. I think for the elementary age stuff (ages 5-12 or so, for non-US people), there are plenty of groups away from school, as you have mentioned. Once you get to the high school age, though, the things tend to be more involved, ie., they almost require the sponsorship of a high school. I guess you could keep doing Boy Scouts, but that doesn't involve guard girls in spandex on the band bus (dang!!!! so many missed opportunities-if only I could've traded some of my book smarts for intelligence of a different sort).
As far as how home schooled kids turn out, I know a pair of brothers that turned out to be the stereotypical weird home schooled kids, except not nearly as smart, and then I know another guy that turned out to be of above average intelligence and very good social skills.
In Georgia a few years ago, they came up with a program that provided scholarships to all graduating high school students in the state with "B" averages (it could've been guaranteed admission, but I'm almost positive it was the HOPE scholarship). Of course, as anyone on /. would've guessed, the number of "B" averages increased by leaps and bounds in the years that followed.
Speaking of true curves, I had a Heats teacher in the Mechanical Engineering Dept. at Univ. of Fla. who truly graded on the curve. I am forgetting his name, but he was an older chinese guy, and he was a lot of fun. He would do a sample distribution of the grades on a graph at the beginning of the semester, and then divide the graph into five regions. Then he would point at the different grade groupings, announcing that the first group was "A", the second was "B", etc., and the last group was "Sacrifice". The accent really added a lot to it...I guess you'd have had to been there.
As an engineer who designs air-conditioning systems all day long, I can safely say that architects make *our* lives difficult by wanting such huge windows, high ceilings, etc.
They never want to give us enough mechanical space, which can make life hard on the maintenance folk, since we have to wedge stuff into places that make it hard to pull coils for cleaning, replace filters, etc. Let's not even talk about architects who want a lay-in ceiling at 9', and have bottom of structure above at 10'3", and expect us to put our ducts between the two. Our ducts aren't the only thing that has to go up there, there are also lights that poke up (typically 6"), fire sprinkler piping, etc. Of course, the contractors are upset with our design when they have trouble fitting stuff.
Large windows just allow lots of heat into buildings. Even if owners were to spring for high-efficiency, insulated windows, they let in five times as much heat as a decently insulated wall, without even accounting for the solar energy they let in (and owners most often want the cheapest single pane windows they can get). I feel like architects nowadays use glass almost as a crutch for making a building look nice. I recently worked on the conversion of a 90-year-old school building into lofts for residential use. Those old school buildings have these huge (20' long x 8' high) windows, single pane, not well sealed. This added significant air conditioning to each apartment, and even if I match the calculated heat gain with my air conditioning capacity, someone next to the window will be warm, just because there will be a thermal layer.
High ceilings cause thermal stratification. This isn't normally a problem in the summer, as the cool air from the air conditioner falls towards the floor, where people want it anyway. In the winter, however, the hot air rises, and you've got to do quite a bit of heating before the warm air layer gets down to person level (unless you have hot water heating under the floors, which I'd like to do in my house when I buy one, but I live in the south, and they don't do much of that down here.)
On the previously mentioned lofts project, the architect did a few apartments where there had previously been an auditorium. Upon walking into the apt, you stood in the living room and could see all the way up to the main ceiling 20' above you. The apartment was one large space, with the back of the apartment being divided into split levels, with the kitchen on the main floor and the bedroom on the upper level. So you could walk from the living room with the extremely high ceiling, directly back into the kitchen with the low ceiling (b/c of the bedroom above it), and then climb stairs to the bedroom, which shared a ceiling with the living room. Standing in the bedroom, you had a bannister that you could stand at and look down into the living room. Also, as an artifact of the history as an auditorium, each apartment had a double glass door centered in a 15' wide x 18' high window. The window serves the dual tasks of letting in/out lots of heat, while also making it easy for any passerby to see directly into the entire apartment (unless you have your 18' high venetian blinds closed). In fact, even if you have blinds, you'd better hope your not backlit when you're doing anything in the apartment. Regarding heating and cooling, the cooling season should produce some stratification, and it'll be somewhat difficult to cool that bedroom. In heating season, though, it'll bake the bedroom and freeze the living room. I warned the architect, but he persisted.
Well, that's just a little sample from an HVAC engineers perspective. Sorry it's so long.
1 Ton of air conditioning equals 12000 Btuh (British thermal units per hour). 3.418 Btuh equals 1 Watt. So 1 ton equals approximately 3510 Watts of heat (or cooling, whichever you prefer).
The Btuh thing is a bit confusing to some, because most people only say "btu", but they can mean "Btuh", as in rate of heating or cooling, or they can actually mean "Btu", which means an actual amount of heat or energy (as in a canister of gas for your barbeque grill). Hope this clears it up for you. BTW, I know this B/C I design air conditioning systems.
Rich
Come on, this "Can't we all just get along" stuff just doesn't work. It is human nature to want to take what someone else has, and I've seen nothing to indicate that people can change human nature. Communists believed that people (especially children) could be educated out of selfish human nature, but that proved wrong.
I see these bumper stickers that say, "You cannot simultaneously prepare for and prevent war.", and that is garbage. As long as there are multiple groups with interests on this earth, the unilateral disarmament of one will only lead to aggression by another group. For that reason, I say that the *only* way to prevent war is to prepare for it. You need to make it extremely painful for anyone else to bother you. The US did this in the cold war, and the Soviets decided they'd just as soon leave us alone. I am all for having a peaceful world, but provided that we're all humans, and at least some of us will be armed, the only way to achieve peace is through deterrence.
Ok, as has been mentioned, this was tried after the French Revolution (and failed, of course). The interesting part is that, for a while, all watches were, by law, required to show decimal time. The watchmakers, though, couldn't make any money selling decimal time watches, so they made the watches cross-compatible. The watch had to show the whole day, as opposed to half a day, since there was no longer an am set of hours and a pm set of hours. So they used one hour hand, but showed both hour scales on the watch. For minutes, however, they needed two hands, with two different scales.
A horologist friend has one of these watches, and a link to a picture is below. We were working on a project to make a clock tower on the Univ. of Fla. campus with, essentially, four clock faces from 300-400 years ago that few people know about (one face for each side). BTW, converting the one revolution per hour signal from an old clock mechanism to output decimal time on a clock face with mechanical gearing is a mess.
Here's the link for the site.
http://www.ce.ufl.edu/%7Echiep/
This takes you to the clock tower project site. Click the 'Dials' link on the left hand side, and then click on 'Revolutionary or Metric Dial' on the page it takes you to.
Good point. At the time that I spoke to him about the computers, I was under the impression that he'd only purchased two, and I was figuring that the problem could be mostly resolved by going to a different supplier for the other computers. As it was, he sent the first computer back for immediate repairs because of some problem, and the second computer is having problems in ACAD 14. It was later that I found out that he had a stack of eight more of these things stacked elsewhere. Oh well. As an additional point, he selected these computers based upon the advice of the guy that runs the small computer consulting business that does our systems administration.
I work at a small engineering firm. The boss' son, who will be taking over in the next couple of years, has a CS & EE degree, and worked at GE & Sandia in majorly geeky stuff, as far as EE and CS goes. I would think that he'd be smart enough to make intelligent computer decisions, but he surprised me recently.
We are looking to upgrade to a newer version of ACAD, and it won't run on Win95 (which most of our 12 or 13 boxes are running). The new version promises to run on Win 98SE or Win XP Pro. So, we are doing a major upgrade in the office, just so all of the computers can make the jump from Win 95 to Win 98SE (I don't know why he won't go to a newer version of Windows). The worst thing is that he just bought a bunch of Compaq Evos, running P4 1.7 GHz, with 128 megs of SDRAM with an Intel 845 chipset (and the obligatory onboard video and sound). That chipset was practically put out by Intel as a joke, because Intel started out matching the P4 exclusively with RDRAM, then everyone yelled for a DDR SDRAM chipset, and then Intel threw out this 845 chipset that only officially supports SDRAM (then 6 months later, they release a mod of that chipset that finally supports DDR SDRAM). The P4 wants high memory bandwith, so you will take a big hit unless you run RDRAM or DDR SDRAM.
It has been bothering me for the past few days that we're going to be stuck with these POS machines for the next few years, and we'll probably have to upgrade machines again when more demanding software needs to be run, and that just means less money into my profit sharing. I explained this whole memory issue to him, after I saw what he'd bought, and his only explanation was that they weren't all *that* slow, and they were cheaper than the pair of Gateways he'd bought a year earlier. I can see how a typical manager type might need to see the well known brand name on the side of each computer to make him feel better, but this guy is a techie. If he would've spent just a little time learning about what is out there right now, we could've gotten set up for around $650 with machines that would have the same CPU's, DDR SDRAM, even Win 98SE, etc., for the same price (around $650, brand name parts, even). Beyond that, who puts anything together nowadays with 128 megs of any sort of RAM, much less someone who is going to run 5 or 6 concurrent sessions of AutoCAD, plus Outlook & Wordperfect? I understand that we don't have the money to be on the edge with our technology, but he could've at least shopped like an educated geek.
I'm not sure if *everyone* needs to know as much as we (techs & geeks) would like for them to know. I've done a lot of reading on economics, and the concept of 'cost of knowledge' really applies here. Earlier this year, the time came for me to build a new computer to replace my 486/120. I spent many many hours reading articles at Toms Hardware, Arstechnica, etc., learning all of the background that I needed to in order to make an optimal decision for a new computer. To get my knowledge, the cost was high, and the benefit (over spending no time learning and getting a Gateway instead) was fairly modest, in terms of the performance bonus I got. But I did things that way, to a great extent, for the knowledge to be gained in the process, and to move me along towards being a proficient Linux geek.
For one of us, growing up around computers and typically enjoying learning about them, the benefit of learning the guts behind everything is worth the cost. But, if you're a senior citizen, death could be stalking at every turn. I don't believe there is much benefit for her in learning anything beyond the bare minimum. That is why there are, and always will be, companies like AOL, Microsoft, Compaq, Dell, etc.
It is true that only a few people who were above the impact floors made it out. This does not mean, however, that we can or even should design buildings to allow people in that situation to make it out alive (as much as we all would've liked to see them make it out).
I'm a mechanical engineer working in the building design industry (HVAC design, though I've done a bit of sprinkler design). Building fire protection systems(firewalls, eggress corridors & stairwells, sprinklers, etc.) are designed around the premise of keeping the fire out of egress paths for long enough that people can safely get out of the building. This typical assumes that you are dealing with a normal fire (not thousands of pounds of fuel/accelerant) and that a massive explosion hasn't just ripped through your building.
From what I know of the WTC case, those planes trashed those egress stairwells so that people from above couldn't use them (does anyone know how the handful of people from the upper floors who did get out managed it?) Regarding the fireproofing coming off of the beams, they still lasted long enough for everyone to get out who had a viable path. When architects put in an egress corridor, I just don't think there is any way that they can start planning for 'What if an airliner hits this building?' or 'What if some nutcase explodes a moving truck-size amfo bomb nearby?'. The costs would be enormous if you were to truly try to make all high-rises events like these survivable, and the benefits would be comparatively small.
Given 9-11, I think there is no chance that passengers will sit idly by and let someone gain control of a plane. However, even if they did, and even if high-rises were somehow hardened, there are many other less-hardened targets, such as stadiums w/ 80,000+ people. That's why killing the people who would harm us makes so much sense.
I know this doesn't address the software engineering concerns, but this quote from the article sort of ticked me off,
"In most engineering fields, Pfleeger says, such disasters trigger industrywide reforms, as the collapse of the World Trade Center seems likely to do for fireproofing in construction."
The fact is, from everything that I've seen and heard, those buildings staying up as long as they did is a *testament* to the fire protection installed in the buildings. I believe they had asbestos covering at least a portion of the metal beams (seems like they had to switch to a different form of insulation at some level, maybe asbestos wasn't allowed anymore?). Regardless, the fact that a building falls down when you run an airliner loaded with lots of jet fuel into it does not speak badly of the engineering practices, and it's sheer stupidity to suggest otherwise. There are lots of reasons to examine fire protection in this country, but 9-11 is not one of them.
I've got a couple of suggestions. Try "Blind Man's Bluff - The Untold Story of American Submarine Espionage", by Sherry Sontag and Christopher Drew. This book has some incredible stories. The chapter about the search for the sunken U.S. sub 'Scorpion' was one of my favorites. They ended up using a method of statistical guessing, outlined in yet another book called "The Theory of the Optimal Search". Another book I really enjoyed was "Skunk Works", by Ben Rich. This book, as you've probably guessed, is all about the history of Lockheed's special project division that developed the U-2, the SR-71, Stealth Fighter, and much other interesting stuff. Ben Rich headed the Skunk Works from 1975 until he retired in 1991. Well, those are two pretty quick reads, and they don't deal with any of the human intelligence stuff, but they have great cold war stories nonetheless.
I had a Thermo professor at Univ. of Florida named Dr. Gater (most engineers who've graduated from UF in the last twenty or so years probably took Thermo I from him). In Thermo I, he wouldn't let students use the graphing type calculators (he might not have even let students use *any* calculators, but it's been a little while, I forget).
When students would whine about his restrictions, he would say something along the lines of, "What about when you're at the urinal, and an engineer at the next urinal over asks about how much sensible cooling you can get from that chiller? You can't use a calculator then." He was (and is) a terrific teacher, even if I dropped Thermo I once, got an F next, then a D+, then, finally a C+. My problem in his class was that I had become accustomed (in other classes) to not going to class (very often, at least), reading the appropriate material, coming to an understanding of the theory by doing a few problems, and then doing pretty well on the tests. Thermodynamics, unfortunately for my GPA, was entirely different (at least under Dr. Gater). You have to do lots of problems in order to truly understand the material, otherwise you're up a creek (and the knowledge is cumulative, so if you got lazy for a few weeks, you were screwed). Thermo II was entirely take home tests (any calculators allowed) and there was no chance to slow down or get lazy since you were always taking a test (you handed on in on Friday, and then he gave you another). I was extremely proud of my B+ (first time around).
On the subject at hand, though, it seems that most people here (especially those with experience as a math tutor, like myself) would agree that students should learn the basic skills without major calculator help. At a certain point (exactly when is up for debate), calculators can become effective learning tools. Most of us also agree that calculators are invaluable for getting the grunt work out of the way once it's second nature to you. Some people have indicated that, on a well designed test, a students math knowledge or ignorance will be exposed, whether he has a nice calculator or not. Unfortunately, it seems that in many, many (I dare say most) classrooms, the tests that are given aren't nearly up to that standard (as evidenced by the sheer ignorance of the people walking into math labs at community colleges around the country, even after they have passed Algebra classes at the college level). The most vocal defenders of calculators in the realms of educators will always point to teachers who are using calculators for truly enlightened teaching, as if they are typical examples, when we all should know that they are not.
Of course, we also can't forget that TI itself is one of the biggest proponents of this movement, and they have a huge financial stake in the matter. When you figure that nearly every high schooler in algebra is buying a $100 calculator, the numbers get pretty significant.