If you talk to someone about global warming, intelligent design, horrible management practices, whatever, you'll find that someone with credentials has written articles, books, etc., that pass the most horrific crud as fact. When journalists site this crud, their own credibility eventually suffers, but there will be a faithful following notwithstanding. Unfortunately, figuring out what is good and what is bad requires passing the Turing Test, which is hard work. You can't just go with the majority opinion. Aristotle said that the Sun goes around the Earth, and basically everyone said that was true for 1,500 years. Can everyone be wrong?
YMMV. Nutrasweet gives me 6 hour migraine-like headaches in the smallest quantities. Getting my tongue wet with DC is too much. My diet drink is water. It's an acquired taste.
As far as i know, the Kindle can be used to read non-DRM books, just as an iPod can play non-DRM mp3's. One can, for example, format Gutenberg books for free, load them onto a Kindle, and read them. There are also DRM works available, but not, for example, Harry Potter. I can't think of another book i'd read under DRM.
So for me, the Kindle should be judged as an electronic reader. Like the Sony, it has a large format, high res, gray scale screen (no color). There's a pause displaying a new screen, but once there, power drain is minimal to keep it there. The batteries last a long time. Books can be text, PDF or web pages. It does WiFi and USB. It can play audio, but at the expense of consuming the batteries. You don't have to play audio. It can display images, but, they are gray scale.
On the down side, it doesn't scroll well (there's that pause). It's larger than a shirt pocket. I prefer the Palm form factor. Portability is important. The Kindle is something like $400, which i consider outrageous.
My old Handspring Visor Platinum has an LCD screen, works well in direct sunlight, ambient room light, and darkness (with backlight), runs more than 20 hours on 2 AAA batteries (10 with backlight), spares can be carried for more endurance, does USB, turns pages quickly, has two font sizes to optimize readability with it's small screen, fits in a shirt pocket, was $110 new (closeout), and can run other apps, like a calendar, memopad, planetarium, and games. There are DRM readers available. I happen to like weasel better. 8 MB RAM/file store allows apps and at least a couple Bible sized books on line. On the downside, it doesn't display images, and it is no longer available. For long battery life in black and white, LCDs rock.
I'm now using a Nokia 770. It fits in a shirt pocket, has stunning color but it is weakest in direct sunlight, does PDF, and web, the text reader: FBReader offers fonts, sizes, and colors, runs 5 hours on a charge, a spare battery can be purchased, was $150 new (closeout), can run other apps including a Palm emulator, does WiFi, Bluetooth and USB. It runs Linux. It comes with a 64 MB flash card, for huge libraries online. A 2 GB flash card allows audio and video, or this stuff can be streamed over WiFi.
Others have talked about how hard or easy the fix might be, and so on. This is about Quality Assurance and the processes that organizations use to attempt to achieve it.
I've worked in environments where a single line fix that isn't an emergency, takes seven weeks. I've also worked in environments where such a fix takes five minutes. In my experience, the quality of such patches is very similar.
In some environments where an emergency break fix takes ten days. The application is broken for at least that amount of time. No amount of persuasion that the fix in hand is better than production will speed it up. The idea is that the process for getting something into production includes so much testing, that things simply aren't broken in production. This approach is problematic. Testing generally does not test everything, despite claims to the contrary. Not a single such environment i've worked for has required code coverage testing. Only one environment in twenty required a code review where another developer looked at the code. Quality gates essentially consisted of a manager asking the developer if certain steps were taken, and if the developer says they did it, then the approval stamp was given. This is worse than useless. It takes time to get the attention of the appropriate manager, while adding no value.
These quality gate environments often also have built silos where a systems admin must perform deployment. A database admin must perform all database changes. And so on. Each of these groups are nameless and faceless. Communication to them is equivalent to email, that is to say, one way. Despite considerable chances for miscommunication, the admin teams are considered infallible. When it turns out that they aren't, and they end up changing the environment, breaking the applications, it often still requires the full cycle to apply fixes.
Another quality gate often enforced is documentation. I used to think that programmers didn't like to write documentation, and therefore avoided this work. However, it turns out that the required documentation typically has no well defined audience. No one ends up reading it, because it has so little to say that they need to know. The developers themselves don't value it, because it is often out of date with respect to the code. Some documentation has required sections where huge volumes of screen shots, ER diagrams, class diagrams, and so on are included that are automatically generated. So any effort towards documentation is considered to be a waste of time.
If you suffer from some of these symptoms, the recommended route is to change the processes. Drop managerial approvals. Include real peer reviews - code reviews. Consider implementing automated regression testing. Pull admins out of isolated silos and into development teams. Require only targeted documentation omitting content that is automatically generated. If possible, get the customer to verify all changes before launch.
If Unix gave us just what we need in an OS, then Version 7 Unix gave us an OS written in a way to ease porting to new hardware. We even booted Unix on Pr1me hardware. The bit that makes a pointer point to an even or odd byte is not the least significant bit in a Pr1me address.
Yeah, yeah, i know, other OS's have been ported. Windows and VMS on Alpha. CP/M on the 8086 and 680000. Mac OS on PPC. But Unix variants are everywhere.
Multics requires hardware support for it's security model, probably the dynamic linking, etc.
Certainly, a Multics machine emulator could be written. Such an emulator would run circles around the original hardware. Multics was not written in an era of gigabytes of RAM. So, a Multics emulator could keep an entire emulated machine in RAM on a pocket computer today, like a $99 Palm. Such an emulator might not be hard to write.
It's not like Seth Shostak is against SETI. He clearly wanted to list some reasons it's worth it, and debunk some of the reason some people have suggested why it might not be.
Ignorance is not bliss - it's only ignorance. --Seth Shostak
If Apple sells and iPhone, and the owner doesn't connect it to a network, it's hard to imagine that Apple actually looses money. A quarter of a million iPhones is a profitable market, one would think. They did release an SDK, so you can use it for non-phone stuff, like a PDA. There are cheaper PDAs, though.
Clearly, they're worried you might use it with T-Mobile or some such, and they wouldn't get their cut. But they make money there, too, right?
I recently picked up a Nokia 770. This device came out a couple years ago, say 2005. In 1985, I worked with a CDC Cyber 205 supercomputer. So, this is really 20 years, not 15. I have benchmark results for both, so why not compare?
The Nokia has 64 MB RAM. The '205 had 16 MB RAM. The Nokia kicks scaler code at about 40 to 100 MIPS. The '205 kicked scaler code at 35 to 70 MIPS. The Nokia has a DSP, which seems to be able to kick about 200 MFLOPS (i could be wrong). The '205 had twin vector pipes with a peak performance of 200 MFLOPS each, but it was rare to get more than 80% of that. My point is that they're comparable. The Nokia came with 192 MB file store, but now has 2.1 GB, and can mount my desktop filesystems over WiFi with better than 1 MB/sec throughput. The '205 had about 1 GB disk, and could mount mag tapes. Both sport native compilers for C, Fortran, etc. The Nokia was about $150. The '205 was about $15,000,000. That's a factor of 100,000 improvement in price/performance. The Nokia runs on batteries and fits in my shirt pocket, with the form factor of my old Palm Pilot. The '205 had a motor-generator power conditioner (the flywheel acts like a battery in power failure) and fit in large machine room with temperature and humidity carefully controlled.
Would i call the Nokia a supercomputer? No. Supercomputers cost more than a million dollars when they are new. Would i build a beowulf cluster of Nokia's? Maybe. With WiFi, one might put together an ad-hoc grid pretty easily. I only have one. But my 4 year old desktop is more than 30 times faster, so it's going to be hard to justify from a pure performance standpoint. Yes, my desktop has better price/performance than the Nokia.
I've not yet run a SETI@Home unit on the Nokia. It'd be much better than the one i ran on the 486/33...
My five year old Palm has become unreliable, and i'm replacing it. I've purchased a Nokia 770. It was about $150, but there were deals as low as $130. It's on closeout - the 800 is out. That's something like $100. It runs Linux. It's not a laptop. It's more shirt pocket form factor.
It comes with a video player, audio player, web browser (it does WiFi, BlueTooth, and USB), email, chat, PDF reader, wordpad (HTML instead of RTF), games like chess, mahjong. There are a bunch of apps that can be downloaded for free, so, presumably, it could be distributed with a good collection.
OK, so there's no keyboard. There's a microphone, but no voice recognition. But that's just a matter of software, right?
More serious is that there does not appear to be a word processor. You can deconvolve Word and read it...
Anyway, with some serious software porting, this device could really kick.
64 MB RAM, 128 MB flash onboard. A slot comes with a 64 MB flash card. I've got a 2 GB flash on order...
You might say that it isn't a laptop. But for me, it is. I intend to use it as i used my old laptop.
Not really. You can have a wire from the inside to the outside attach to an antenna.
The vacuum chamber is a good insulator, but the computer will be generating heat on the inside. So, it's still best if the computer produces as little heat as possible, and if there is a way to get rid of the heat. I suspect that Venus will cook it eventually, anyway. Plenty can be learned in a few hours, though.
Your investments, in order are, first, join an astronomy club. Many clubs have the equipment you want. At that point, you might be done. But, i'd still subscribe to one of the astronomy magazines. Astronomy, or Sky & Telescope. Both, if you have time to read them. Many libraries carry one or the other. Club membership will offer you a discount on either or both magazines.
Last year, i bought a scope with a $1000 maximum budget. I decided that astrophotography will come second. I purchased a good visual astronomy scope. This is a ten inch (254 mm) Newtonian reflector on an Alt-Az mount. The mount does not track the sky, but it comes with a computer, which helps locate objects in the sky. The Orion xt10i is about $800. This leaves money for a laser collimator ($65), an Oxygen 3 filter ($90), a 2x barlow ($40), and possibly a variable moon filter ($30) (also good for Venus). I've been very happy with it. The computer has taught me what is possible to see very quickly. Set observing goals - double stars, the messier list, etc. Get monthly sky charts from
To get into photography, i'd go with a much smaller instrument, perhaps an 80 mm APO refractor. The idea is that a smaller instrument requires a smaller (cheaper) mount. To get the best results of anyone in my club, it appears that about $9,000 is needed. Or, just use the club equipment. You'll probably want help using the equipment, so you should join a club.
written by John E. Bortle, which describes the scale. I'm guessing that he knows something about this Bortle scale.
While i consider my house in the inner-city, Class 9, the description doesn't cover it. I regularly observe from my driveway, which has a local street light, but which is across the street from a grocery store parking lot. I don't bring a flashlight, as there is enough light to find a lost contact lens.
But with an eight or ten inch scope, and an Oxygen 3 filter ($80 US), most nebulae are evident. You need the eight or so inches of aperture, since the filter rejects most light - it's a narrow band filter. M-16 (the Eagle Nebula) can be seen even right between those parking lot flood lights.
So, i often observe from the driveway because it takes the least time. And neighbors walking by sometimes ask what i'm doing, which allows me to show them. If i've forgotten something, it's right inside the house. If it's cold, i can warm up by going back inside. But also, i don't have to wait for my eyes to dark-adapt.
The worse light pollution of all comes from the Sun. When the Sun is up, it's hard to see much. I've only been able to see Venus, Jupiter, Mars and Saturn when the Sun is up. Class 10, at least. And it seems to be up about half the time. I have a solar filter, but with it you can only see the Sun.
The article just says "upper level", but doesn't hint at what the courses are.
I took Calculus in high school. I'm sure i got A's in it. Everyone did. All six of us. The course was offered, and we self selected. We were the ones who were going to get it. But the article was about not encouraging weaker students. As far as i know, everyone who didn't take it self selected out of it. But really, with such a small class, if there was a weak student, they'd get lots of help. So, i don't see how it would bring down the school grade point average. It's the MEAP test that schools care about, as far as i can tell, not their GPA.
Taking Calculus in high school did nothing for my SATs. The SAT exam didn't cover any calculus. What it did is give me two semesters of engineering math head start. I knew that's what i was going to do.
Security bugs are more appropriately names insecurity bugs.
Lots of security bugs are really insecurity features.
I had a Unix system where i had a normal user login, but did not have the root login. It was noticed that a mail client, usual for Unix, was setuid to root - which was unusual. So, it was fired up, and then, the shell escape command was issued. Presto. Root shell. Very handy.
Electrostatics. Moon dust gets everywhere and sticks. Drop a hammer, and it actually falls.
Just installed FC5 with SELinux turned on.
on
SELinux by Example
·
· Score: 1
Fedora Core 5 gives you the option of turning SELinux on or not. I had no prior experience with it, and decided to see how bad it is. All security is bad. Sometimes, you have to live with it. I was not able to get user home directories to work in Apache. The error logs were unrevealing. Turning off SELinux fixed everything. (Google suggested i try that. Google knows everything, though some of the things it knows are wrong.)
So, before i can turn SELinux back on, i have to go through the SELinux learning curve. A book like this could help. I've not yet looked for on-line docs.
OK. How about a fine? Let's see. It costs what, a billion dollars (a year) to cope with spam, right? Triple damages would be $3,000,000,000. Oh, and add interest. Until the fine is paid in full, the spammer and family must live in poverty equivelent to the worse poverty on Earth.
Bill Gates could afford it. But for most of us, jail starts to look pretty good.
I just hope the UK has equally tough spammer laws.
Part of the problem with current laptops is that they are really portable desktops. So, your desktop CPU consumes 80 watts and has a heat pump, heat sink, CPU fan, and box fan to cool it. So, these portable desktops produce all this heat and dumps it into your lap.
Really. What I want in a laptop is a laptop. It can be 'slow'. But consider this. 10 MIPS is fast. 100 MIPS can currently be cooled without a fan. I want to take a 10x hit on speed, and gain 10x in battery life and reduced heat.
For that matter, flash memory is 'big enough' now to use as disk. I could have a totally silent laptop. Hey, then it could have good sound quality, and it wouldn't be pointless.
At that point, exploding batteries, etc., will be a thing of the past.
What will it take? Well, for one thing, it will take good software. Eye candy consumes batteries. Drop it. Huge programs take a long time to load. I'm willing to bet that movies could be played with the right hardware/software combination. Not that I want to watch movies on my laptop. I'd go for the monochrome version that gets 20x battery life.
In 1999, I ran a mission critical web server, apps, database, on not just a desktop, but one that was too slow (at the time) to use as a desktop. No one wanted it. It was an original 100 Mhz Pentium. We scrounged 128 MB RAM for it.
One day, the fan died, and the machine was fried. But, another old desktop box was available, and in a couple hours, the 'new' box was restored from backups and was on the air.
We had battery backup for the entire server room. And, if power wasn't restored pretty quickly, a diesel generator kicked in. All this stuff got tested twice a year. None of it helped much. Our main problem was people tripping on power cords. My own desktop had higher up time.
On two occasions I have been asked [by members of Parliament!], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question. -- Charles Babbage
Slashdot Mirror
Plenty of people who don't like radio like podcasts on an mp3 player.
I read books on a Palm i'd never read on paper. Too much to carry around.
And, your standard novel doesn't also do your calendar, etc.
If you talk to someone about global warming, intelligent design, horrible management practices, whatever, you'll find that someone with credentials has written articles, books, etc., that pass the most horrific crud as fact. When journalists site this crud, their own credibility eventually suffers, but there will be a faithful following notwithstanding. Unfortunately, figuring out what is good and what is bad requires passing the Turing Test, which is hard work. You can't just go with the majority opinion. Aristotle said that the Sun goes around the Earth, and basically everyone said that was true for 1,500 years. Can everyone be wrong?
YMMV. Nutrasweet gives me 6 hour migraine-like headaches in the smallest quantities. Getting my tongue wet with DC is too much. My diet drink is water. It's an acquired taste.
As far as i know, the Kindle can be used to read non-DRM books, just as an iPod can play non-DRM mp3's. One can, for example, format Gutenberg books for free, load them onto a Kindle, and read them. There are also DRM works available, but not, for example, Harry Potter. I can't think of another book i'd read under DRM.
So for me, the Kindle should be judged as an electronic reader. Like the Sony, it has a large format, high res, gray scale screen (no color). There's a pause displaying a new screen, but once there, power drain is minimal to keep it there. The batteries last a long time. Books can be text, PDF or web pages. It does WiFi and USB. It can play audio, but at the expense of consuming the batteries. You don't have to play audio. It can display images, but, they are gray scale.
On the down side, it doesn't scroll well (there's that pause). It's larger than a shirt pocket. I prefer the Palm form factor. Portability is important. The Kindle is something like $400, which i consider outrageous.
My old Handspring Visor Platinum has an LCD screen, works well in direct sunlight, ambient room light, and darkness (with backlight), runs more than 20 hours on 2 AAA batteries (10 with backlight), spares can be carried for more endurance, does USB, turns pages quickly, has two font sizes to optimize readability with it's small screen, fits in a shirt pocket, was $110 new (closeout), and can run other apps, like a calendar, memopad, planetarium, and games. There are DRM readers available. I happen to like weasel better. 8 MB RAM/file store allows apps and at least a couple Bible sized books on line. On the downside, it doesn't display images, and it is no longer available. For long battery life in black and white, LCDs rock.
I'm now using a Nokia 770. It fits in a shirt pocket, has stunning color but it is weakest in direct sunlight, does PDF, and web, the text reader: FBReader offers fonts, sizes, and colors, runs 5 hours on a charge, a spare battery can be purchased, was $150 new (closeout), can run other apps including a Palm emulator, does WiFi, Bluetooth and USB. It runs Linux. It comes with a 64 MB flash card, for huge libraries online. A 2 GB flash card allows audio and video, or this stuff can be streamed over WiFi.
Others have talked about how hard or easy the fix might be, and so on. This is about Quality Assurance and the processes that organizations use to attempt to achieve it.
I've worked in environments where a single line fix that isn't an emergency, takes seven weeks. I've also worked in environments where such a fix takes five minutes. In my experience, the quality of such patches is very similar.
In some environments where an emergency break fix takes ten days. The application is broken for at least that amount of time. No amount of persuasion that the fix in hand is better than production will speed it up. The idea is that the process for getting something into production includes so much testing, that things simply aren't broken in production. This approach is problematic. Testing generally does not test everything, despite claims to the contrary. Not a single such environment i've worked for has required code coverage testing. Only one environment in twenty required a code review where another developer looked at the code. Quality gates essentially consisted of a manager asking the developer if certain steps were taken, and if the developer says they did it, then the approval stamp was given. This is worse than useless. It takes time to get the attention of the appropriate manager, while adding no value.
These quality gate environments often also have built silos where a systems admin must perform deployment. A database admin must perform all database changes. And so on. Each of these groups are nameless and faceless. Communication to them is equivalent to email, that is to say, one way. Despite considerable chances for miscommunication, the admin teams are considered infallible. When it turns out that they aren't, and they end up changing the environment, breaking the applications, it often still requires the full cycle to apply fixes.
Another quality gate often enforced is documentation. I used to think that programmers didn't like to write documentation, and therefore avoided this work. However, it turns out that the required documentation typically has no well defined audience. No one ends up reading it, because it has so little to say that they need to know. The developers themselves don't value it, because it is often out of date with respect to the code. Some documentation has required sections where huge volumes of screen shots, ER diagrams, class diagrams, and so on are included that are automatically generated. So any effort towards documentation is considered to be a waste of time.
If you suffer from some of these symptoms, the recommended route is to change the processes. Drop managerial approvals. Include real peer reviews - code reviews. Consider implementing automated regression testing. Pull admins out of isolated silos and into development teams. Require only targeted documentation omitting content that is automatically generated. If possible, get the customer to verify all changes before launch.
If Unix gave us just what we need in an OS, then Version 7 Unix gave us an OS written in a way to ease porting to new hardware. We even booted Unix on Pr1me hardware. The bit that makes a pointer point to an even or odd byte is not the least significant bit in a Pr1me address.
Yeah, yeah, i know, other OS's have been ported. Windows and VMS on Alpha. CP/M on the 8086 and 680000. Mac OS on PPC. But Unix variants are everywhere.
Multics requires hardware support for it's security model, probably the dynamic linking, etc.
Certainly, a Multics machine emulator could be written. Such an emulator would run circles around the original hardware. Multics was not written in an era of gigabytes of RAM. So, a Multics emulator could keep an entire emulated machine in RAM on a pocket computer today, like a $99 Palm. Such an emulator might not be hard to write.
It's not like Seth Shostak is against SETI. He clearly wanted to list some reasons it's worth it, and debunk some of the reason some people have suggested why it might not be.
Ignorance is not bliss - it's only ignorance.
--Seth Shostak
If Apple sells and iPhone, and the owner doesn't connect it to a network, it's hard to imagine that Apple actually looses money. A quarter of a million iPhones is a profitable market, one would think. They did release an SDK, so you can use it for non-phone stuff, like a PDA. There are cheaper PDAs, though.
Clearly, they're worried you might use it with T-Mobile or some such, and they wouldn't get their cut. But they make money there, too, right?
I recently picked up a Nokia 770. This device came out a couple years ago, say 2005. In 1985, I worked with a CDC Cyber 205 supercomputer. So, this is really 20 years, not 15. I have benchmark results for both, so why not compare?
The Nokia has 64 MB RAM. The '205 had 16 MB RAM. The Nokia kicks scaler code at about 40 to 100 MIPS. The '205 kicked scaler code at 35 to 70 MIPS. The Nokia has a DSP, which seems to be able to kick about 200 MFLOPS (i could be wrong). The '205 had twin vector pipes with a peak performance of 200 MFLOPS each, but it was rare to get more than 80% of that. My point is that they're comparable. The Nokia came with 192 MB file store, but now has 2.1 GB, and can mount my desktop filesystems over WiFi with better than 1 MB/sec throughput. The '205 had about 1 GB disk, and could mount mag tapes. Both sport native compilers for C, Fortran, etc. The Nokia was about $150. The '205 was about $15,000,000. That's a factor of 100,000 improvement in price/performance. The Nokia runs on batteries and fits in my shirt pocket, with the form factor of my old Palm Pilot. The '205 had a motor-generator power conditioner (the flywheel acts like a battery in power failure) and fit in large machine room with temperature and humidity carefully controlled.
Would i call the Nokia a supercomputer? No. Supercomputers cost more than a million dollars when they are new. Would i build a beowulf cluster of Nokia's? Maybe. With WiFi, one might put together an ad-hoc grid pretty easily. I only have one. But my 4 year old desktop is more than 30 times faster, so it's going to be hard to justify from a pure performance standpoint. Yes, my desktop has better price/performance than the Nokia.
I've not yet run a SETI@Home unit on the Nokia. It'd be much better than the one i ran on the 486/33...
My five year old Palm has become unreliable, and i'm replacing it. I've purchased a Nokia 770. It was about $150, but there were deals as low as $130. It's on closeout - the 800 is out. That's something like $100. It runs Linux. It's not a laptop. It's more shirt pocket form factor.
It comes with a video player, audio player, web browser (it does WiFi, BlueTooth, and USB), email, chat, PDF reader, wordpad (HTML instead of RTF), games like chess, mahjong. There are a bunch of apps that can be downloaded for free, so, presumably, it could be distributed with a good collection.
OK, so there's no keyboard. There's a microphone, but no voice recognition. But that's just a matter of software, right?
More serious is that there does not appear to be a word processor. You can deconvolve Word and read it...
Anyway, with some serious software porting, this device could really kick.
64 MB RAM, 128 MB flash onboard. A slot comes with a 64 MB flash card. I've got a 2 GB flash on order...
You might say that it isn't a laptop. But for me, it is. I intend to use it as i used my old laptop.
> Wouldn't that make it less than 100% sealed? :)
Of course not. Wire doesn't pass gas.
Rocket Science. That would be Partial Differential Equations with Boundary Values (math).
I've taken the course, and have compared the time and difficulty with that of other projects.
Multi-tasking operating systems seem more difficult, and take longer to write and get correct.
So, i'd call it Rocket Science.
Not really. You can have a wire from the inside to the outside attach to an antenna.
The vacuum chamber is a good insulator, but the computer will be generating heat on the inside. So, it's still best if the computer produces as little heat as possible, and if there is a way to get rid of the heat. I suspect that Venus will cook it eventually, anyway. Plenty can be learned in a few hours, though.
Your investments, in order are, first, join an astronomy club. Many clubs have the equipment you want.
At that point, you might be done. But, i'd still subscribe to one of the astronomy magazines. Astronomy,
or Sky & Telescope. Both, if you have time to read them. Many libraries carry one or the other. Club membership will offer you a discount on either or both magazines.
Last year, i bought a scope with a $1000 maximum budget. I decided that astrophotography will come second.
I purchased a good visual astronomy scope. This is a ten inch (254 mm) Newtonian reflector on an Alt-Az mount.
The mount does not track the sky, but it comes with a computer, which helps locate objects in the sky.
The Orion xt10i is about $800. This leaves money for a laser collimator ($65), an Oxygen 3 filter ($90), a 2x barlow ($40), and possibly a variable moon filter ($30) (also good for Venus). I've been very happy with it. The computer has taught me what is possible to see very quickly. Set observing goals - double stars, the messier list, etc. Get monthly sky charts from
http://skymaps.com/downloads.html
To get into photography, i'd go with a much smaller instrument, perhaps an 80 mm APO refractor. The idea is
that a smaller instrument requires a smaller (cheaper) mount. To get the best results of anyone in my club, it appears that about $9,000 is needed. Or, just use the club equipment. You'll probably want help using the equipment, so you should join a club.
Did i mention that you should join a club?
There's a Sky & Telescope article,
http://www.skyandtelescope.com/resources/darksky/3304011.html?page=4&c=y
written by John E. Bortle, which describes the scale. I'm guessing that he knows something about this Bortle scale.
While i consider my house in the inner-city, Class 9, the description doesn't cover it. I regularly observe from my driveway, which has a local street light, but which is across the street from a grocery store parking lot. I don't bring a flashlight, as there is enough light to find a lost contact lens.
But with an eight or ten inch scope, and an Oxygen 3 filter ($80 US), most nebulae are evident. You need the eight or so inches of aperture, since the filter rejects most light - it's a narrow band filter. M-16 (the Eagle Nebula) can be seen even right between those parking lot flood lights.
So, i often observe from the driveway because it takes the least time. And neighbors walking by sometimes ask what i'm doing, which allows me to show them. If i've forgotten something, it's right inside the house. If it's cold, i can warm up by going back inside. But also, i don't have to wait for my eyes to dark-adapt.
The worse light pollution of all comes from the Sun. When the Sun is up, it's hard to see much. I've only been able to see Venus, Jupiter, Mars and Saturn when the Sun is up. Class 10, at least. And it seems to be up about half the time. I have a solar filter, but with it you can only see the Sun.
Put him on dialup for the duration.
The article just says "upper level", but doesn't hint at what the courses are.
I took Calculus in high school. I'm sure i got A's in it. Everyone did. All six of us. The course was offered, and we self selected. We were the ones who were going to get it. But the article was about not encouraging weaker students. As far as i know, everyone who didn't take it self selected out of it. But really, with such a small class, if there was a weak student, they'd get lots of help. So, i don't see how it would bring down the school grade point average. It's the MEAP test that schools care about, as far as i can tell, not their GPA.
Taking Calculus in high school did nothing for my SATs. The SAT exam didn't cover any calculus. What it did is give me two semesters of engineering math head start. I knew that's what i was going to do.
Security bugs are more appropriately names insecurity bugs.
Lots of security bugs are really insecurity features.
I had a Unix system where i had a normal user login, but did not have
the root login. It was noticed that a mail client, usual for Unix,
was setuid to root - which was unusual. So, it was fired up, and
then, the shell escape command was issued. Presto. Root shell.
Very handy.
The Daily WTF has this kinda stuff:
http://forums.worsethanfailure.com/forums/
Any sufficiently advanced bug is indistinguishable from a feature.
-- Rich Kulawiec
Electrostatics. Moon dust gets everywhere and sticks. Drop a hammer, and it actually falls.
Fedora Core 5 gives you the option of turning SELinux on or not. I had no prior experience with it, and decided to see how bad it is. All security is bad. Sometimes, you have to live with it. I was not able to get user home directories to work in Apache. The error logs were unrevealing. Turning off SELinux fixed everything. (Google suggested i try that. Google knows everything, though some of the things it knows are wrong.)
So, before i can turn SELinux back on, i have to go through the SELinux learning curve. A book like this could help. I've not yet looked for on-line docs.
Bill Gates could afford it. But for most of us, jail starts to look pretty good.
I just hope the UK has equally tough spammer laws.
This is what i think of jail and poverty.
Part of the problem with current laptops is that they are really portable desktops. So, your desktop CPU consumes 80 watts and has a heat pump, heat sink, CPU fan, and box fan to cool it. So, these portable desktops produce all this heat and dumps it into your lap.
Really. What I want in a laptop is a laptop. It can be 'slow'. But consider this. 10 MIPS is fast. 100 MIPS can currently be cooled without a fan. I want to take a 10x hit on speed, and gain 10x in battery life and reduced heat.
For that matter, flash memory is 'big enough' now to use as disk. I could have a totally silent laptop. Hey, then it could have good sound quality, and it wouldn't be pointless.
At that point, exploding batteries, etc., will be a thing of the past.
What will it take? Well, for one thing, it will take good software. Eye candy consumes batteries. Drop it. Huge programs take a long time to load. I'm willing to bet that movies could be played with the right hardware/software combination. Not that I want to watch movies on my laptop. I'd go for the monochrome version that gets 20x battery life.
In 1999, I ran a mission critical web server, apps, database, on not just a desktop, but one that was too slow (at the time) to use as a desktop. No one wanted it. It was an original 100 Mhz Pentium. We scrounged 128 MB RAM for it.
One day, the fan died, and the machine was fried. But, another old desktop box was available, and in a couple hours, the 'new' box was restored from backups and was on the air.
We had battery backup for the entire server room. And, if power wasn't restored pretty quickly, a diesel generator kicked in. All this stuff got tested twice a year. None of it helped much. Our main problem was people tripping on power cords. My own desktop had higher up time.
The Pentium ran Solaris x86.
On two occasions I have been asked [by members of Parliament!], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.
-- Charles Babbage