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Study: Ad-Free Internet Would Cost Everyone $230-a-Year

green is the enemy Re:$230 isn't the problem (611 comments)

I found myself willingly paying a $6/month subscription to a website (this surprised me quite a bit): Their model is very interesting. You do not pay for content, but with subscription you get more bandwidth and generally smoother access to their content (video), as well as wiki editing ability, unlimited "mylists", time shifted "live broadcasts"... basically just better service and perks, but not more content. They also run the "related products" ads below the main content, but with a twist: all "related product" links are user-submitted. It's actually fun to browse those.

about three weeks ago

Why the "NASA Tested Space Drive" Is Bad Science

green is the enemy Re:A little behind the times (315 comments)

Yes, the paper handles the vacuum issue very badly (Sections II and IV contradict each other, and Figure 22 says "(In 750mm Air)"). However, convective air flow is unlikely to be the cause of the anomalous thrust. I would expect convection to have a slow time constant as objects heat up and cool down, but the thrust turns on and off quickly in the paper.

I would like to see more plausible causes of the anomalous thrust. Any new physics discovery is extremely unlikely here, but so far the proposed explanations have been lacking.

Ionization of air might be one such possibility. The very high-Q cavity with tens of watts of input power may reach electric fields strong enough to ionize the air inside the cavity. The ions/electrons/air would need to escape the cavity somehow to produce thrust.

about a month ago

NASA Tests Microwave Space Drive

green is the enemy Re:They used a vacuum, and a serious one at that. (201 comments)

There is another clue in the paper: In the lower right corner of Figure 22 it says "(In 750mm Air)". So at least the tapered cavity test article was not run in a vacuum. However, it is reasonable to read that that their earlier tests with a pillbox cavity were done in a vacuum. You'd have to agree that they were sloppy in specifying the exact conditions under which each test was performed. I'm looking forward to independent tests of this concept that are undoubtedly coming given the publicity this received.

about a month ago

NASA Tests Microwave Space Drive

green is the enemy Re:They used a vacuum, and a serious one at that. (201 comments)

Someone made this paper available for download. Their writeup makes it seem like they perform the experiment in a vacuum, except for one tidbit in the "Summary and Forward Work" section:

Vacuum compatible RF amplifiers with power ranges of up to 125 watts will allow testing at vacuum conditions which was not possible using our current RF amplifiers due to the presence of electrolytic capacitors.

This makes it sound as if these tests were not conducted in vacuum after all...

about a month and a half ago

NASA Tests Microwave Space Drive

green is the enemy Re:Sensationalism at its worst (201 comments)

I haven't seen this vacuum issue addressed by anyone after some searching. To me it seems premature to speculate about quantum vacuum effects when interactions with air seem very likely. Perhaps they planned to perform these experiments in a vacuum, but didn't quite get to that point when the abstract was due? At this point, they may have finished the vacuum version of these experiments, so may have some results to present. If someone does know, please pitch in.

about a month and a half ago

NASA Tests Microwave Space Drive

green is the enemy Re:Ugh (201 comments)

Yeah, that paper should be rejected. The results are totally useless. I wonder how many people went "WTF?" upon reading "...within a stainless steel vacuum chamber with the door closed but at ambient atmospheric pressure."

about a month and a half ago

NASA Tests Microwave Space Drive

green is the enemy Re:KSP (201 comments)

Double-check your units. 0.4 kg will accelerate at 1e-4 m/s^2 under 40e-6 N of force. That's ~3000 m/s per year (3.15569e7 seconds in a year).

about a month and a half ago

A Look At NASA's Orion Project

green is the enemy Re:The one good feature of ARM (108 comments)

Can you point to good criticism of the Asteroid Redirect Mission? I can't think of a better way to kick-start in situ space resource utilization, which is what we need for sustained human presence in space. Perhaps you mean the manned portion of this mission? The redirection of an asteroid into a close orbit is a very good idea by itself. Of course, spacecraft sent to study this asteroid and try extracting resources from it should mostly be unmanned (and will be).

about 2 months ago

Russian Government Edits Wikipedia On Flight MH17

green is the enemy pigs (667 comments)

All sides in this are acting like pigs, the Russians, Ukrainians and the Ukrainian separatists. The Russians are and the separatists are throwing around unsubstantiated accusations. Even the Ukrainians are not releasing the volumes of radar (including military radar) and air traffic control data that surely exist. The worst ones are of course the ones who shot at the plane. Since they are hiding and spewing misinformation, it's obvious they are not even a tiny bit sorry for accidentally shooting down a civilian plane. Their behavior makes it look like the plane was deliberately targeted, truly a work of evil.

about 2 months ago

Malaysian Passenger Plane Reportedly Shot Down Over Ukraine

green is the enemy Re:Some more info: (752 comments)

The people talking in the background say that the plane exploded in the air (big explosion) and debris was still raining down as the smoke was just starting to come up from the ground. They also mentioned "it's a good thing they brought it," pretty obviously referring to an anti-aircraft missile system.

about 2 months ago

Aliens and the Fermi Paradox

green is the enemy Re:Progenitors? (686 comments)

Can you speculate why you think space might be competitive? Space resources are mind-bogglingly plentiful. Just the main belt asteroids have enough to support 10 quadrillion people. Imagine dismantling moons or even Mars-sized planets for raw materials. You can sustain unimaginably huge civilizations. Why would there be a need to fight for resources?

about 3 months ago

Science Moneyball: The Secret to a Successful Academic Career

green is the enemy Re:Meanwhile, on Wall Street (42 comments)

In this case the relationship is not necessarily directly causal. If you can bring in the grant money, you can get a career. The quantity of papers may simply be a consequence of running a successful research program.

about 3 months ago

Robots Will Pave the Way To Mars

green is the enemy Re:Ad astra per aspera (95 comments)

NASA's Asteroid Redirect Mission seems to be the only serious effort in this area. I applaud them for their ambition. While this mission is being marketed as a stepping stone for a manned Mars mission, it also happens to be a very good way to get started with in-situ space resource utilization. Anyone have any insight on how the plans for this mission are progressing?

about 4 months ago

Google Unveils Self-Driving Car With No Steering Wheel

green is the enemy heavy traffic (583 comments)

I'm curious how automated cars will handle heavy traffic. It's often hard to find an opening to merge into a busy lane, or make a left turn through heavy traffic. Would the automated car wait 10 minutes for an opening? Would it be able to drive aggressively to avoid wasting time like this?

about 4 months ago

Data Mining Shows How Down-Voting Leads To Vicious Circle of Negative Feedback

green is the enemy Re:Slashdot's moderating system (293 comments)

It would be interesting to add a feature that would allow filtering comments based on their number of mods overall. Both upmods and downmods would count the same. The more controversial comments would really stick out. A good compromise between troll filtering and making unpopular opinions visible might be at least a score of 3 OR at least 3 mods total.

about 4 months ago

US Navy Wants Smart Robots With Morals, Ethics

green is the enemy Re:Humans Can Not (165 comments)

Some of these can be answered somewhat rationally.

For example would a moral robot have refused to function in the Vietnam War?

The decision whether to fight in the Vietnam War is political. A robot does not have a vote, so should not participate in politics at all.

Would a drone take out an enemy in Somalia knowing that that terrorist was a US citizen?

If the enemy is judged to be seriously threatening US interests, the drone should take him out, just as a police officer would take out a dangerous criminal.

How many innocent deaths are permissible if a valuable target can be destroyed?

In this case the drone should weigh human lives against other human lives. Can it be estimated how many human lives are at risk if the valuable target remains intact? Not just the numbers but the probability of harm should be taken into account. This type of decision is usually up to the higher level commanders that have more information on hand.

If a robot acts as a fair player could it use high tech weapons against an enemy that had only rifles that were made prior to WWII?

There is no ethical issue here. Use the most effective weapons. Minimize losses on your side. Try to make the enemy surrender with minimal losses on their side (i.e. don't nuke them).

If many troops are injured should a medical robot save two enemy or one US soldier who will take all of the robot's attention and time?

The robot must assume that we will fight until we win. Treating a US soldier contributes to the success of the war campaign, potentially saving many lives in the future. Treating injured enemy soldiers may actually cause losses because the enemies may fight again (if they can't be taken into custody). When including the probability of future losses of human lives, the choice is clear: treat the US soldier.

When it comes to moral issues and behaviors there are often no points of agreement by humans so just how does one program a robot to deal with moral conflicts?

Use utilitarian ethics. Not many rules are required. When estimating potential future human lives lost, assume your side is going to win. Do not venture into politics. (Of course there could be something terribly wrong with this reasoning, so fire away.)

about 4 months ago

Asteroid Impacts Bigger Risk Than Thought

green is the enemy comets (172 comments)

The article authors say that most of the dangerous asteroids are already being tracked (additional tracking efforts under way), and can potentially be deflected since collisions can be predicted decades into the future. That's only a half-truth. Comets in the outer solar system are too dark to detect in their present locations, but can arrive at Earth very quickly. There will not be enough time to deflect them... Statistically, what percentage of impacts are from objects originating in the outer solar system? Is that even possible to determine?

about 5 months ago

Ad Tracking: Is Anything Being Done?

green is the enemy Re:solution (303 comments)

There is potentially a Scenario 4:

Most of the content of the website is user-generated. The main costs are for hosting. There are free accounts and paid accounts. The paid accounts bring in the majority of the revenue. They differ from free accounts by relatively minor, but convenient perks, like greater bandwidth from the server, or ability to post more often. Free account holders still have access to all the content. People eventually value your service enough to pay a small monthly fee and get the perks. There are no ads, period.

This model can work for Slashdot, Facebook, YouTube and many others.

about 5 months ago

Can Science Ever Be "Settled?"

green is the enemy cannot be "settled"? (497 comments)

This discussion turned out mostly useless because the concept of "settled" was not well defined. Taking the definition to be "completely describes reality", all evidence points to this being impossible. My question is why is this so? Is this a fundamental property of nature? Has this property itself been studied?

about 6 months ago

Hubble Discovers Water Plumes Over Europa

green is the enemy Re:Hmmm (74 comments)

The radiation environment around Europa most likely breaks apart any complex molecules that came from the ocean. The best possibility is a lander that would dig into the regolith. Unfortunately, looks like the Juno mission will not help even with locating landing spots on Europa. Its camera is too wide-angle.

about 9 months ago


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