This case illustrates the problems we run into when we try to define something like "terrorism." One of the assignments I give my students is to try to define terrorism. For example, they can check off boxes saying it only targets civilians or it targets anyone including military personell, or saying it is intended to cause terror or is intended to fulfill some other objective. Then I give them the folowing list of cases -- all real-world examples with names removed to reduce bias when applying the student's definition:
Case 1 Powerful government troops ravage insurgent resources to hasten the end of civil war. They burn their way through a swath of rebel territory, sparing civilians and (sometimes) their homes but destroying crops, livestock, buildings, and railways. After seizing a major city, they expel its entire population and put the city to the torch. The government commander says, ?If the people raise a howl against my barbarity and cruelty, I will answer that war is war and not popularity-seeking. If they want peace, they and their relatives must stop the war.?
Case 2 A loosely-knit group of dissidents bands together to protest unfair tax policy. Wearing disguises, they trespass on the property of a corporation favored by the government and destroy the corporation?s goods.
Case 3 A group fighting a "war of liberation" against a government it calls ?an unjust occupying power? secretly plants a bomb in a hotel being used as a military headquarters. The group calls ahead, warning of the attack, but the blast still claims scores of victims, including many civilians in the hotel.
Case 4 Marxist rebels in uniform invade a foreign embassy and take hostages during a civil war, demanding the release of ?political prisoners.? No hostages are harmed by the rebels, but the government counter-attack kills several hostages in the cross-fire. Was the hostage-taking by the rebels terrorism?
Case 5 A band of political rebels, aiming to overthrow a government they claim is oppressive, assassinates the head of state.
Case 6 After a revolution in Country A, Country B decides to do everything in its power to overthrow the new leaders of Country A. It begins funding a guerrilla army that attacks Country A from another country next door (call it Country C). Country B also builds army bases in the next door country and allows the guerrilla army to use its bases. Country A supplies almost all of the weapons and supplies of the guerrilla army fighting Country A. The guerrillas generally try to avoid fighting Country A's army. Instead, they attack clinics, schools, and farms. Sometimes they mine the roads. Many, many civilians are killed and maimed by the Country B-supported guerrillas. Consistently, the guerrillas raid Country A and then retreat into Country C for protection.
Case 7 In wartime, the armed forces of a country bomb the cities of another country, hoping that the victims of the bombing will be terrorized, become angry at their own government, and then overthrow it.
Case 8 During peacetime, a weapons scientist goes to work for Country A. Fearing that his weapons might give Country A an advantage, Country B -- the longtime foe of Country A ? sends secret agents to assassinate the scientist. The assassination is carried out while the scientist is staying in a neutral country.
Case 9 Retaliating for an attack on its headquarters, an armed political group (neither uniformed nor employed by a government) bombs a warship, killing many soldiers.
Case 10 After it finds out that an environmental group is planning to conduct a peaceful but illegal protest, a government secretly plants a bomb on the group?s ship while it is docked in a neutral, peaceful country. The blast sinks the ship, killing the group?s photographer.
Case 11 Following a horrific incident in which nine of its citizens are killed by terrorists, a government retaliates by sending out agents to assassinate the terrorists. These agents mist
This study committed the worst type of selection error: selection on the dependent variable. In this study (or at least in the article's description) the dependent variable is successful penetration. The value of this variable is 1 (ie yes) in every case. Therefore, the dependent variable doesn't vary. Now the independent variable (type of OS on target system) does vary, but unless the dataset includes unsuccessful penetrations (or transforms the dependent variable into a comparative measure based on average penetrations per OS/server) absolutely nothing of value can be learned. This is research design 101, folks: variables need to vary.
...on those damned "affiliate" sites. You know -- the ones that have made searching for actual information on stuff like history and science all but impossible without wading through dozens of virtually identical copies of Amazon web pages. This sort of thing seems easy to filter out, so I wonder why Google hasn't done so. Oh, the howls that will erupt when Google finally gets around to pulling the rug out from all of these free riders....
When they passed the 12th Amendment (removing prior language on election of Pres/VP), we still had the Second. When they passed Amendments 13-15, removing huge chunks of the prewar Constitution, we still had the 2nd. When they passed the income tax, removing the prohibition on unequal taxation, we still had the 2nd. When they passed prohibition -- and struck it from the Constitution -- we still had the 2nd.
Your statement is a slogan, not an argument. Whole chunks have been removed from the Constitution (for the better, IMO) while gun owners sat and did nothing. Sheesh, this type of rah-rah-ism gets modded up?
Pay attention in Social Studies class. Or even if you can't bear to learn the basics of your government, Google "first amendment" before running your mouth:
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.
I have two takes on this story. First, I do find it a bit offensive to presume cheating on the part of students and to require them to "prove" they didn't cheat rather than the burden of proof running the other way. I do believe that if you expect certain behavior from people and let them know your expectations, then they are more likely to confirm them. This is the same reason that I find the anti-cheating posters in our classrooms at Wright State University offensive -- students know they aren't supposed to cheat, so the posters just create the impression that it's a pervasive part of the academic experience.
Second, that little quip about financial compensation is completely off-base. Students pay to learn, and once the prof has decided that they'll have a better learning experience if they submit to the site (presumably because they will feel forced to think for themselves instead of copying from term paper mills) they have no "right" to compensation. The practice is offensive, but from an educational standpoint, it is little different than the professor using their papers in class as examples for others. Either way, other people benefit from the student's work without compensation for the student. That's the way education works. The fact that antiplagiarism sites make money from their line of business (and the examples submitted by the students) is of no import, as long as they aren't selling the essays as part of an anthology or something. It's a feedback loop within the educational process and even though I disapprove of the practice, nobody's "rights" are violated.
I HATE those damnable red dots (cap codes). They were incredibly distracting on Trilogy Tuesday and now they're everywhere! I sorely hope that they were not present on Somethings' Gotta Give, or else the studios will rejoice that their defiled prints actually caught someone. Watermarking? OK -- but NO RED DOTS!!!
Hindus: Fear not, I'm on a crusade against patterns of dots, not single ones...
I'll go ahead and stick up for PowerPoint. As a university instructor, I use plenty of interactive stuff like simulation exercises and group discussions. Nevertheless, sometimes a lecture is the way to go, particularly when dealing with a complex and unfamiliar body of material.
What is the alternative to PowerPoint (or other slide-show programs) in academia? Hmmm... I remember chalkboard lectures that were hard to read (and I know my handwriting is awful) and often a confusing mess of arrows, half-erased comments, and lists without bullet points to mazke it clear when each item begins. Then there was the time involved in writing the material on the chalkboard/whiteboard and the annoying frequency with with the lecturer (myself included) would talk while writing, thus addressing his/her comments to the board instead of the class.
Then there were overheads. These lost the spontaneity of chalkboard comments, but dramatically improved legibility. Unfortunately, they were also (usually) monochrome -- even when I printed color overheads, I had to be careful since I was paying for my own color ink. Moreover, they lost the ability to change a diagram easily, adding and removing elements to illustrate one's point. Finally, they made it difficult to integrate video or animation, since the overhead projector was likely to be in the way of the film projector or TV.
Enter PowerPoint. Now I have the ability to include video, so when I talk about patterns of voting, I can play campaign commercials that sought to appeal to particular blocs of voters. Saying the economy matters is one thing. Putting up a graph comparing economic performance to vote share in elections is better (but can be confusing without color). Doing both and then watching Reagan's Morning in America ads is best. Powerpoint makes it simpler (though not exactly easy, given its hostility to non-Microsoft video formats) to do this sort of thing.
I disagree with many suggestions made by other comments. My advice:
1. Use color, but try to use style as well and don't rely on red/green differences. Remember, 10% of males in your audience are color-blind.
2. Use text, but not more than six or seven words per subpoint. This is enough to communicate just about any conclusion, and then further subpoints can walk through each element of your argument if needed.
3. Never use anything less than 14 points, preferably at least 18. People in the back of the room and people with less-than-perfect vision need to be able to see.
4. DO NOT MEMORIZE YOUR TALK! I coached speech and debate for years, and while the formal memorized speech has its place, that place is almost never in the type of presentation where you'll be using PowerPoint. Practice your speech until you have an extemporaneous but fairly efficient style.
5. Writing your points is the easy part. Decorating then with visual geegaws is only moderately more taxing. The really hard part is coming up with a real-world example of what your talking about. Once you have the example, use PowerPoint to communicate it with some amount of pizazz. After all, you don't need your audience to remember the particulars of the example (so little text is neeeded); rather, you want them to understand the meaning of whatever point they just wrote down. This is the place for audiovisual dazzle, not your main points...
6. Don't let the flash distract from your points. The key is to follow rule # 5 for examples, but to keep the points themselves distinct and consistent. Don't mix the visual style with which you present text. Don't use distracting animation for anything you want the audience to copy down.
7. Get to the room early and TEST YOUR PRESENTATION on the available equipment. Perhaps the fonts and software on the presentation machine are different from your own. Perhaps the equipment isn't working (see # 8). Perhaps the resolution of the scre
...when she dissed her best friend who helped her move in next door by nabbing her fiance. Well, actually that was interesting but it turned into a long-term relationship. Dex just makes my skin crawl and the cam and journal got really boring after that. I mean, there's only so much gardening crap a person can read about. It was more interesting before she settled down. I think I've checked the cam like four times in the last year...
I teach this data (prior studies) as part of my lecture on Race in Politics (I like to disabuse my students of the notion that race is a useful biological marker or indicator of genetic variance). Here are the answers from my reading of other studies:
1. Chimps have remained a distinct species filling their ecological niche for far, far longer than homo sapiens. Genetic changes have had more time to accumulate.
2. The 2000 indidivuals from whom we all descend didn't have kids that continued in isolation from the others in that group. Rather, they interbred continuously, meaning that what genetic variance they had was them passed around to all of their descendants over time. There were more than 2000 chimps, presumably, and they tended to split off and diverge more rapidly afterwards due to the fact that their habitat is more likely to split into isolated "islands" over time. (Humans can exist in many habitats, even with Stone Age tools).
3. "The Urge to Merge" -- Every time two previously isolated groups of humans make contact, they start to mate. This results in the little variance we do have being shuffled around even more, further reducing average variance.
Of course, not all dams will inflict all types of damage. Still, indirect effects can be powerful. The unexpected rate of siltation behind Hoover led to the construction of another large dam (Glen Canyon)upriver, which had its own economic and environmental costs. Incidentally, simple ecosystems like deserts, tundra, etc turn out to be much more fragile than more complex ecosystems like rainforests (which have many more feedback loops to resist change). In general, the Colorado River is considered one of the worst ecological disasters in the country, though controlling the flow of water has made irrigation possible (bad for the environment, good for humans).
Actually I was trying to keep them separate, but I may have been unclear about that. The Colorado River has many dams, and only a trickle actually makes it past all of them.
The Three Gorges Dam is a disaster. Frankly, even the Hoover Dam isn't all roses. Large dam projects flood huge areas of land, eliminating entire ecosystems, displacing large numbers of people, destroying archaeological evidence, and submerging economically productive land. There's something to hate for everyone, whether liberal or conservative. Check out the ecology of the Colorado River sometime. Interestingly, the things can even increase CO2 concentrations by flooding green areas. The effect can be quite substantial.
There are also practical difficulties, like the buildup of silt (which always seems to happen much faster than anyone anticipates) and the costs of construction and maintenance (they aren't as cheap as one might expect).
Are they better than fossil fuel plants? Probably. Personally, I like them a lot more than nuclear plants (largely for economic reasons). But I just can't find it in me to be happy about their construction.
A quick and dirty summary of the downside of dams can be found here, though a quick Google search will reveal many more pages for and against.
You're correct -- wealthier counties were more likely to have optical scanners instead of punch ballots, and therefore they had lower rates of error. But that's not the whole story. Even in the optical counties, errors were still disproportionately made by Democrats. Of course, the only ones we're sure of are the overvotes (marking a candidate and then writing in that ticket as well, thus spoiling one's ballot). Moreover, Gore never asked for a recount of overvotes, only the undervotes. Perhaps the Dems had more first-time voters. In any case, these things aren't politically neutral -- different systems favor one party's voters over those of the other party.
One of the problems uncovered in Florida after the whole election/chad fiasco was that even in counties with optical scanners, there were still significant overvotes and undervotes (spoiled ballots). What's even more interesting is that while the overall error rate was lower than that for punch ballots (no hanging chad to worry about), the errors were not party-neutral. It really did appear to be the case that those attempting to vote Democratic were worse at using the optical system. Electronic voting offers the prospect of error-checking and instant feedback while still keeping the vote secret. Of course, that doesn't mean we still don't have to worry about the technical and verification issues.
I seem to recall that webcasters weren't allowed to make the services "interactive" a while back. Users weren't permitted to select songs. Obviously this is different, but I wonder just how much a service can "react" to a user's playlist before it crosses the line to letting the user select each song?
1. I believe you have your betas and your gammas mixed up. Beta radiation is trivial to stop, being charged and all. It's the gamma rays that require such extensive shielding.
2. Even with the best materials, heavy bombardment by neutrons does create radioactive material over time. I agree with you on the proportions of carbon in the short term, but even these rare events start to add up when you're talking about the number and energy levels of neutrons in fusion reactions.
3. Fusion is better than fission -- but why does everyone embrace a polluting technology so eagerly when renewable, non-polluting ones are already here?
1. I agreee with you about the risk of uncontrollable reactions. Fusion is clearly better than fission -- but it still has its own set of costs and hazards.
2. As for "most" you are again correct. 95% of the radioactivity is locked away in 3% of the waste. Fusion reactors won't have that high-level waste to worry about. Still, long term (century-long) storage of low-level radioactive waste is still an economic, political, and environmental headache. Moreover, if fusion is adopted much more extensivly than fission, the absolute quesntity of waste may actually go up -- although at least the stuff decays (relatively) quickly.
ALL of the major approaches to fusion power generate neutrons. Yes, the standard alpha/beta/gamma counts are low, but the neutrons will render the reactor walls radioactive. This can be mitigated, but not avoided. The result is a substantial amount of low-level radioactive waste that takes a century to return to background levels (ie can be disposed of without resorting to a nuclear waste dump). Care to suggest a fusion reaction being tested that doesn't emit neutrons?
This still isn't quite true. Reactor walls are indeed rendered radioactive by prolonged exposure to neutron radiation. This problem can be mitigated by choice of materials, but it cannot be eliminated. Luckily, this low-level waste decays quickly to background levels in a century (much quicker than fission byproducts) but that's still a long time, economically speaking.
Good point, though even low-energy beta radiation is still enough to make me give Tritium a wide berth. Luckily, its half-life is short. Of course, this still leaves the reactor walls and other low-level radioactive waste.
Less than 3% of nuclear waste from conventional plants is spent fuel. Now, it's true that most of the radioactivity is locked up in that tiny bit of maeterial, but the other 97% of the waste is still a real pain in the ass to safely store until it is no longer hazardous. For more info on the composition of nuclear waste, check out the DOE summary of waste categories that it made as part of its Yucca Mountain work.
Slashdot Mirror
This case illustrates the problems we run into when we try to define something like "terrorism." One of the assignments I give my students is to try to define terrorism. For example, they can check off boxes saying it only targets civilians or it targets anyone including military personell, or saying it is intended to cause terror or is intended to fulfill some other objective. Then I give them the folowing list of cases -- all real-world examples with names removed to reduce bias when applying the student's definition:
Case 1
Powerful government troops ravage insurgent resources to hasten the end of civil war. They burn their way through a swath of rebel territory, sparing civilians and (sometimes) their homes but destroying crops, livestock, buildings, and railways. After seizing a major city, they expel its entire population and put the city to the torch. The government commander says, ?If the people raise a howl against my barbarity and cruelty, I will answer that war is war and not popularity-seeking. If they want peace, they and their relatives must stop the war.?
Case 2
A loosely-knit group of dissidents bands together to protest unfair tax policy. Wearing disguises, they trespass on the property of a corporation favored by the government and destroy the corporation?s goods.
Case 3
A group fighting a "war of liberation" against a government it calls ?an unjust occupying power? secretly plants a bomb in a hotel being used as a military headquarters. The group calls ahead, warning of the attack, but the blast still claims scores of victims, including many civilians in the hotel.
Case 4
Marxist rebels in uniform invade a foreign embassy and take hostages during a civil war, demanding the release of ?political prisoners.? No hostages are harmed by the rebels, but the government counter-attack kills several hostages in the cross-fire. Was the hostage-taking by the rebels terrorism?
Case 5
A band of political rebels, aiming to overthrow a government they claim is oppressive, assassinates the head of state.
Case 6
After a revolution in Country A, Country B decides to do everything in its power to overthrow the new leaders of Country A. It begins funding a guerrilla army that attacks Country A from another country next door (call it Country C). Country B also builds army bases in the next door country and allows the guerrilla army to use its bases. Country A supplies almost all of the weapons and supplies of the guerrilla army fighting Country A. The guerrillas generally try to avoid fighting Country A's army. Instead, they attack clinics, schools, and farms. Sometimes they mine the roads. Many, many civilians are killed and maimed by the Country B-supported guerrillas. Consistently, the guerrillas raid Country A and then retreat into Country C for protection.
Case 7
In wartime, the armed forces of a country bomb the cities of another country, hoping that the victims of the bombing will be terrorized, become angry at their own government, and then overthrow it.
Case 8
During peacetime, a weapons scientist goes to work for Country A. Fearing that his weapons might give Country A an advantage, Country B -- the longtime foe of Country A ? sends secret agents to assassinate the scientist. The assassination is carried out while the scientist is staying in a neutral country.
Case 9
Retaliating for an attack on its headquarters, an armed political group (neither uniformed nor employed by a government) bombs a warship, killing many soldiers.
Case 10
After it finds out that an environmental group is planning to conduct a peaceful but illegal protest, a government secretly plants a bomb on the group?s ship while it is docked in a neutral, peaceful country. The blast sinks the ship, killing the group?s photographer.
Case 11
Following a horrific incident in which nine of its citizens are killed by terrorists, a government retaliates by sending out agents to assassinate the terrorists. These agents mist
This study committed the worst type of selection error: selection on the dependent variable. In this study (or at least in the article's description) the dependent variable is successful penetration. The value of this variable is 1 (ie yes) in every case. Therefore, the dependent variable doesn't vary. Now the independent variable (type of OS on target system) does vary, but unless the dataset includes unsuccessful penetrations (or transforms the dependent variable into a comparative measure based on average penetrations per OS/server) absolutely nothing of value can be learned. This is research design 101, folks: variables need to vary.
...on those damned "affiliate" sites. You know -- the ones that have made searching for actual information on stuff like history and science all but impossible without wading through dozens of virtually identical copies of Amazon web pages. This sort of thing seems easy to filter out, so I wonder why Google hasn't done so. Oh, the howls that will erupt when Google finally gets around to pulling the rug out from all of these free riders....
A collection of reviews from actual scientists is available right here, for those who are tired reading the opinions of the uninformed.....
When they passed the 12th Amendment (removing prior language on election of Pres/VP), we still had the Second. When they passed Amendments 13-15, removing huge chunks of the prewar Constitution, we still had the 2nd. When they passed the income tax, removing the prohibition on unequal taxation, we still had the 2nd. When they passed prohibition -- and struck it from the Constitution -- we still had the 2nd.
Your statement is a slogan, not an argument. Whole chunks have been removed from the Constitution (for the better, IMO) while gun owners sat and did nothing. Sheesh, this type of rah-rah-ism gets modded up?
Pay attention in Social Studies class. Or even if you can't bear to learn the basics of your government, Google "first amendment" before running your mouth:
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.
I have two takes on this story. First, I do find it a bit offensive to presume cheating on the part of students and to require them to "prove" they didn't cheat rather than the burden of proof running the other way. I do believe that if you expect certain behavior from people and let them know your expectations, then they are more likely to confirm them. This is the same reason that I find the anti-cheating posters in our classrooms at Wright State University offensive -- students know they aren't supposed to cheat, so the posters just create the impression that it's a pervasive part of the academic experience.
Second, that little quip about financial compensation is completely off-base. Students pay to learn, and once the prof has decided that they'll have a better learning experience if they submit to the site (presumably because they will feel forced to think for themselves instead of copying from term paper mills) they have no "right" to compensation. The practice is offensive, but from an educational standpoint, it is little different than the professor using their papers in class as examples for others. Either way, other people benefit from the student's work without compensation for the student. That's the way education works. The fact that antiplagiarism sites make money from their line of business (and the examples submitted by the students) is of no import, as long as they aren't selling the essays as part of an anthology or something. It's a feedback loop within the educational process and even though I disapprove of the practice, nobody's "rights" are violated.
I HATE those damnable red dots (cap codes). They were incredibly distracting on Trilogy Tuesday and now they're everywhere! I sorely hope that they were not present on Somethings' Gotta Give, or else the studios will rejoice that their defiled prints actually caught someone. Watermarking? OK -- but NO RED DOTS!!! Hindus: Fear not, I'm on a crusade against patterns of dots, not single ones...
I'll go ahead and stick up for PowerPoint. As a university instructor, I use plenty of interactive stuff like simulation exercises and group discussions. Nevertheless, sometimes a lecture is the way to go, particularly when dealing with a complex and unfamiliar body of material.
What is the alternative to PowerPoint (or other slide-show programs) in academia? Hmmm... I remember chalkboard lectures that were hard to read (and I know my handwriting is awful) and often a confusing mess of arrows, half-erased comments, and lists without bullet points to mazke it clear when each item begins. Then there was the time involved in writing the material on the chalkboard/whiteboard and the annoying frequency with with the lecturer (myself included) would talk while writing, thus addressing his/her comments to the board instead of the class.
Then there were overheads. These lost the spontaneity of chalkboard comments, but dramatically improved legibility. Unfortunately, they were also (usually) monochrome -- even when I printed color overheads, I had to be careful since I was paying for my own color ink. Moreover, they lost the ability to change a diagram easily, adding and removing elements to illustrate one's point. Finally, they made it difficult to integrate video or animation, since the overhead projector was likely to be in the way of the film projector or TV.
Enter PowerPoint. Now I have the ability to include video, so when I talk about patterns of voting, I can play campaign commercials that sought to appeal to particular blocs of voters. Saying the economy matters is one thing. Putting up a graph comparing economic performance to vote share in elections is better (but can be confusing without color). Doing both and then watching Reagan's Morning in America ads is best. Powerpoint makes it simpler (though not exactly easy, given its hostility to non-Microsoft video formats) to do this sort of thing.
I disagree with many suggestions made by other comments. My advice:
1. Use color, but try to use style as well and don't rely on red/green differences. Remember, 10% of males in your audience are color-blind.
2. Use text, but not more than six or seven words per subpoint. This is enough to communicate just about any conclusion, and then further subpoints can walk through each element of your argument if needed.
3. Never use anything less than 14 points, preferably at least 18. People in the back of the room and people with less-than-perfect vision need to be able to see.
4. DO NOT MEMORIZE YOUR TALK! I coached speech and debate for years, and while the formal memorized speech has its place, that place is almost never in the type of presentation where you'll be using PowerPoint. Practice your speech until you have an extemporaneous but fairly efficient style.
5. Writing your points is the easy part. Decorating then with visual geegaws is only moderately more taxing. The really hard part is coming up with a real-world example of what your talking about. Once you have the example, use PowerPoint to communicate it with some amount of pizazz. After all, you don't need your audience to remember the particulars of the example (so little text is neeeded); rather, you want them to understand the meaning of whatever point they just wrote down. This is the place for audiovisual dazzle, not your main points...
6. Don't let the flash distract from your points. The key is to follow rule # 5 for examples, but to keep the points themselves distinct and consistent. Don't mix the visual style with which you present text. Don't use distracting animation for anything you want the audience to copy down.
7. Get to the room early and TEST YOUR PRESENTATION on the available equipment. Perhaps the fonts and software on the presentation machine are different from your own. Perhaps the equipment isn't working (see # 8). Perhaps the resolution of the scre
...when she dissed her best friend who helped her move in next door by nabbing her fiance. Well, actually that was interesting but it turned into a long-term relationship. Dex just makes my skin crawl and the cam and journal got really boring after that. I mean, there's only so much gardening crap a person can read about. It was more interesting before she settled down. I think I've checked the cam like four times in the last year...
I teach this data (prior studies) as part of my lecture on Race in Politics (I like to disabuse my students of the notion that race is a useful biological marker or indicator of genetic variance). Here are the answers from my reading of other studies:
1. Chimps have remained a distinct species filling their ecological niche for far, far longer than homo sapiens. Genetic changes have had more time to accumulate.
2. The 2000 indidivuals from whom we all descend didn't have kids that continued in isolation from the others in that group. Rather, they interbred continuously, meaning that what genetic variance they had was them passed around to all of their descendants over time. There were more than 2000 chimps, presumably, and they tended to split off and diverge more rapidly afterwards due to the fact that their habitat is more likely to split into isolated "islands" over time. (Humans can exist in many habitats, even with Stone Age tools).
3. "The Urge to Merge" -- Every time two previously isolated groups of humans make contact, they start to mate. This results in the little variance we do have being shuffled around even more, further reducing average variance.
Ah, I see now. Are you confusing the Hoover on the Colorado with the Grand Coulee dam on the Columbia?
Of course, not all dams will inflict all types of damage. Still, indirect effects can be powerful. The unexpected rate of siltation behind Hoover led to the construction of another large dam (Glen Canyon)upriver, which had its own economic and environmental costs. Incidentally, simple ecosystems like deserts, tundra, etc turn out to be much more fragile than more complex ecosystems like rainforests (which have many more feedback loops to resist change). In general, the Colorado River is considered one of the worst ecological disasters in the country, though controlling the flow of water has made irrigation possible (bad for the environment, good for humans).
Of course, Three Gorges is far, far worse.
Actually I was trying to keep them separate, but I may have been unclear about that. The Colorado River has many dams, and only a trickle actually makes it past all of them.
The Three Gorges Dam is a disaster. Frankly, even the Hoover Dam isn't all roses. Large dam projects flood huge areas of land, eliminating entire ecosystems, displacing large numbers of people, destroying archaeological evidence, and submerging economically productive land. There's something to hate for everyone, whether liberal or conservative. Check out the ecology of the Colorado River sometime. Interestingly, the things can even increase CO2 concentrations by flooding green areas. The effect can be quite substantial.
There are also practical difficulties, like the buildup of silt (which always seems to happen much faster than anyone anticipates) and the costs of construction and maintenance (they aren't as cheap as one might expect).
Are they better than fossil fuel plants? Probably. Personally, I like them a lot more than nuclear plants (largely for economic reasons). But I just can't find it in me to be happy about their construction.
A quick and dirty summary of the downside of dams can be found here, though a quick Google search will reveal many more pages for and against.
You're correct -- wealthier counties were more likely to have optical scanners instead of punch ballots, and therefore they had lower rates of error. But that's not the whole story. Even in the optical counties, errors were still disproportionately made by Democrats. Of course, the only ones we're sure of are the overvotes (marking a candidate and then writing in that ticket as well, thus spoiling one's ballot). Moreover, Gore never asked for a recount of overvotes, only the undervotes. Perhaps the Dems had more first-time voters. In any case, these things aren't politically neutral -- different systems favor one party's voters over those of the other party.
One of the problems uncovered in Florida after the whole election/chad fiasco was that even in counties with optical scanners, there were still significant overvotes and undervotes (spoiled ballots). What's even more interesting is that while the overall error rate was lower than that for punch ballots (no hanging chad to worry about), the errors were not party-neutral. It really did appear to be the case that those attempting to vote Democratic were worse at using the optical system. Electronic voting offers the prospect of error-checking and instant feedback while still keeping the vote secret. Of course, that doesn't mean we still don't have to worry about the technical and verification issues.
OK, I know this isn't polite, but this post needs to be at the top! I wouldn't have bothered reading so far if I'd seen it first....
Too bad poster was AC, they deserve some credit.
I seem to recall that webcasters weren't allowed to make the services "interactive" a while back. Users weren't permitted to select songs. Obviously this is different, but I wonder just how much a service can "react" to a user's playlist before it crosses the line to letting the user select each song?
1. I believe you have your betas and your gammas mixed up. Beta radiation is trivial to stop, being charged and all. It's the gamma rays that require such extensive shielding.
2. Even with the best materials, heavy bombardment by neutrons does create radioactive material over time. I agree with you on the proportions of carbon in the short term, but even these rare events start to add up when you're talking about the number and energy levels of neutrons in fusion reactions.
3. Fusion is better than fission -- but why does everyone embrace a polluting technology so eagerly when renewable, non-polluting ones are already here?
1. I agreee with you about the risk of uncontrollable reactions. Fusion is clearly better than fission -- but it still has its own set of costs and hazards.
2. As for "most" you are again correct. 95% of the radioactivity is locked away in 3% of the waste. Fusion reactors won't have that high-level waste to worry about. Still, long term (century-long) storage of low-level radioactive waste is still an economic, political, and environmental headache. Moreover, if fusion is adopted much more extensivly than fission, the absolute quesntity of waste may actually go up -- although at least the stuff decays (relatively) quickly.
ALL of the major approaches to fusion power generate neutrons. Yes, the standard alpha/beta/gamma counts are low, but the neutrons will render the reactor walls radioactive. This can be mitigated, but not avoided. The result is a substantial amount of low-level radioactive waste that takes a century to return to background levels (ie can be disposed of without resorting to a nuclear waste dump). Care to suggest a fusion reaction being tested that doesn't emit neutrons?
This still isn't quite true. Reactor walls are indeed rendered radioactive by prolonged exposure to neutron radiation. This problem can be mitigated by choice of materials, but it cannot be eliminated. Luckily, this low-level waste decays quickly to background levels in a century (much quicker than fission byproducts) but that's still a long time, economically speaking.
Good point, though even low-energy beta radiation is still enough to make me give Tritium a wide berth. Luckily, its half-life is short. Of course, this still leaves the reactor walls and other low-level radioactive waste.
Less than 3% of nuclear waste from conventional plants is spent fuel. Now, it's true that most of the radioactivity is locked up in that tiny bit of maeterial, but the other 97% of the waste is still a real pain in the ass to safely store until it is no longer hazardous. For more info on the composition of nuclear waste, check out the DOE summary of waste categories that it made as part of its Yucca Mountain work.