Look, we're talking about a small temperature change. Possibly enough to change tundra to tiaga. So instead of dwarf swamp birch and arctic shrub willow, you have black spruce. Whoop-de-do. A hundred year old tree that gives you ONE stud.
The place where you might get a change that passed the tipping point for agriculture would be at the northern edge of current agricultural zones.
Even here, the land just isn't valuable enough to make much work worthwhile.
In the Edmonton, Alberta area bush land within the agricultural region, and not in close proximity to a significant city (Significant = has a farm implement dealership) uncleared bush land goes for 90,000 to 180,000 per quarter section (160 acres) It will typically cost another thousand dollars an acre to clear it of spruce and poplar. Depending on the trees and a local mill this may be recoverable from wood sales.
At that point you can farm it.
This is WITHIN the present ag zone.
On the edge of the ag zone, you likely have a more limited set of crops. Possibly only pasture.
Permafrost is potentially deep -- tens to hundreds of feet. It usually isn't drained worth spit. The moss that grows on top/is frozen inside typically has a pH of around 4. Due to the low pH it has almost no nutrients that are available to 'normal' plants. Can it be built up into soil? Probably. But it's not trivial, and would be vastly expensive in a region that is far from being short of land.
A dinosaur killer pretty much knocks out higher life.
Most plagues kill off under 90% of the potential victims.
A dinokiller rock will devastate a continent, and provide nuclear winter over most of the rest of the planet. Smaller rocks may leave a hemisphere habitable.
If you aren't in the way of the rock itself, most fatalities will be from starvation and civil unrest.
A disease kills you more directly, alhough in a serious pandemic, civil unrest will also play it's role.
One year after a pandemic, you can still grow crops,
1. We spend lots more time inside. We spend far more time in close proximity to each other. If the flu strain has an infections time before overt symptoms show, then it would be vectored quickly through travel.
2. Our medical system is very good at dealing with a small number of victims. A pandemic would overwhelm it. Flu kills through respirtory failure. How many ventilators are there in a hospital? 10? 50? Not a lot of help when you have 20,000 sick people at your door.
3. Announcing the pandemic would likely trigger panic. People would flee the cities, likely carrying the virus with them. If 20% of people are sick, another 20% refuse to go to work for fear of catching it, and a further 20% decide it's time to spend a month at hte lake cottage, then 60% of your work force is absent. The economy stops.
In large 3d buildings, having a solution that goes through walls is a Bad Idea (TM)
A directional or a non-penetrating signal is ideal, especially if it is modulated in a way it is still useful after a bounce.
So you wire a house with a wifi hotspot in each room, that either broadcasts on about 10 GHz with 2 mW, or modulates an LED.
The LED has an advantage. You can see it. So you orient yourself so that your device can see it.
The downside of this sort of thing is that it's not just a 'buy it at Best Buy and plug it in" but that it is infra structure that requires enough smarts to read a 30 page manual and make sense of it.
If your primary concern is snapshots, then a phone with a 3 MP sensor is adequate. They will take shots that look ok as a 5x8 electronic frame or a web page.
Paper printouts above the snapshot size push the envelope of phone cameras.
The problem with most point and shoot cameras is that you compose using an LCD screen -- difficult to do in full sun. Your hands are less stable than your head, so an eyepiece viewfinder tends to make for less motion blur.
Much of 'decent photographs' is composition, not equipment. One of the best pictures I took was with a Kodak Starmite box camera.
Previous poster commented about getting the entry level DSLRs from either Canon or Nikon. I'll add Olympus to that list. They have one that is weather resistant, and substantially lighter.
The SLR gives you:
* Sharper lenses. Prints 16 x24 that look good are easily doable with most lenses. * Optical zoom. * Larger sensor => greater sharpness, better low light behaviour. * Viewfinder composition. * Better autofocus. * Faster response to pushing the shutter. (Important for active subjects like kids and squirrels.)
The Phone camera gives you: * It's usually with you. * It's very light weight.
*****
Taking decent pictures is far more than your equipment. Much of good picture taking is artistic, not technical. Google photography tutorial. The second thing is take lots of pictures and throw 90% of them away.
If you go with the DSLR, spend a week with the manual. Read 3-5 pages about a feature set, go out and take 100 pictures using that feature set. Repeat. Doing this will make you familiar with everything that the camera can do.
Look at hundreds of pictures. Which are good? Why? What should be different.
The bigger problem if we use enough geothermal to freeze the upper mantle: Plate tectonics grinds to a halt and in a few million years all the continents erode down to tidal flats.
My brother is a prof in microbiology at New Mexico State. Every two years he taught the introductory genetics course. He said that it was a course that he had to relearn each time. The material in the first two weeks (roughly equivalent to what you get in high school) wouldn't have changed much, but everything else was a whole new ball game. It would take him a couple months to decide on a text, and then he still would photocopy a dozen journal articles for the course.
The best option IMHO would be that your license was valid for ALL releases of the book, but you could choose what release or even include multliple releases of certain modules.
I'm not so much worried about redacted stuff as I am about fashions in teaching. The 4th edition of Dirr's "Propagation guide to Woody Ornamentals" is a solid technical manual. The 7th edition is a pretty garden book with 90% of the nitty-gritty details gone.
I respectfully disagree with some of Ms. Stover's points.
Overall there seems to be some confusion between "Renewable" "Zero Impact" and "Expandable indefinitely"
Some of this confusion is in the public mind. I'll agree that many people consider "renewable" to mean "until the sun grows cold" Meanwhile there are some low impact resources that do run out after a few decades.
Yes, even renewable sources have a cost of operation. That does not mean they are a bad idea.
Let's take another look:
1. The Blythe solar project is expected to use 600 acre feet of water per year. To put that in perspective that is the amount of water to irrigate 120 acres of tomatoes in California's San Joachin valley. I live near a 2 GW coal fired power plant. For cooling they have a 3 square mile pond. In our climate a dugout evaporates about 4 feet a year. So just the evaporative losses alone account for roughly 7200 acre feet per year. Given that the pond is about half uncovered even in midwinter, I suspect that the additional evaporation from it being hotter water than a farmer's dugout raises this evaporative amount considerably.
Yes, water is more scarce in the desert. However compare the water use by the power plant compared to the water used by either industry or the residents that will use that power.
I'll agree the solar PV power is a marginally green technology at this time.
Report card: Renewable: Long term. Impact: Water use -- on the order of 1/10 that of conventional power. Expansion: Moderate. Very large expansion can alter local climate and heat balance. (Solar thermal is overall darker than native desert, so the area will experience an overall temperature increase.
Geothermal: Geothemal can use injected water, but depending on the nature of the hot rock formation, they will cool off the rocks. There is some work being done on drilling in very hot rock. This would mean that, like some classes of water well, each well has a finite life span.
Report card: Renewable: Each installation has a limited lifespan. Use of directional drilling technology may allow each installation to harvest the heat from several cubic miles of crust. Impact: Requires reinjection of water. The use of air cooled condensers (Like at the Blythe project above) would reduce this considerably. Expansion: Natural sites fairly rare. Quite expandable when we can drill hot rock.
Wind Power.
Citing the rare earth magnets as a non-recoverable cost is disingenuous. They would be reused in the next turbine. And they aren't that rare. They are just difficult to separate. The concrete is not much concrete. Many cities have at least 8000 miles of sidewalk..
Report card: Renewable: Indefinately. Impact: Cost of construction is significant. Given their relatively short lives, it may make sense to use steel pylons for foundations. My understanding is that they have short lives because the tech keeps improving, and that after 3-4 years it is worth replacing a 2 MW unit with a 5 MW unit because they already have the site permits, and the power line right of way. There is a good market for used wind turbines. Good sites are rare, and usually not convienient to consumption. Requires extensive power grid infra-structure increases. Expansion: Lots of room for expansion. Windfarms can co-exist with other agricultural use.
Biomass: Argueably the best way to use biomass is with the residue of regular crops. A good case can be made for extracting syngas from any biomass feed stock, and returning the charcoal to the land to create terra pretta. Some research needs to be done to see if this is viable in temperate climates. There are methods for fermenting celluose using a bacterial process for breaking the cellulose into sugar, then yeast to make alchohol. This is a much more complex process than distallation for syngas.
I have also seen the numbers (Scientific American, many years ago) that for a Tennessee based power plant t
My reading of the summary says that they claim that is opaque in one direction and transparent in the other.
Consider the following thought experiment: Assume that this material works the same way for far-infrared as it does for visible light.
In a well insulated cylinder place a sheet of this material across the interior of the cylinder so that light can pass to the left, but not to the right.
Now the material in the right end of the cylinder is emmitting infra-red radiation. It can pass through the material. This warms up the left side, and cools off the right side.
Now we have a temperature difference, so we can run a heat engine. Voila! perpetual motion.
Now if the material doesn't do this with room temperature radiation, then we have to put it in a red hot environment. Will the material still work at those temps?
I agree syslog locally, and to a remote host. Finding differences between the two logs (for a given host) is your first clue that something is amiss.
OpenBSD at least has a method that a file can be marked appendable, but not rewritable. This is enforced by the kernel, and cannot be reset without rebooting the computer. And if your computer is set up properly it doesn't set up any external routes until after it has gone into secure mode.
The proposal is to have a chain of events, so that the hash of the previous message is used as part of encryption of the next one. Which seems to me to mean that overwriting any byte early in the file would make the rest of the file unreadable.
This is one I'd reject for contravening the KISS principle. The complexity doesn't gain you much of anything.
Much of the expense comparison depends on the size/newness of the RV. If your primary goal is travel -- new campground every night, driving 400-600 miles per day then a large RV will cost enough more in fuel to eat up the motel savings. But a small RV is still a reasonable proposition.
I know of several retired folks that have the big RV's towing a small car. Their pattern is an annual cycle, spending two to six weeks in one spot. Their family are scattered over the country.
Another advantage: When you visit, your hosts don't have to make a room up for you. You are fairly self contained. This reduces a lot of the "Fish & visitors..." effect.
I have a niece who has 5 kids. They aren't rich, but are comfortable. They are considering buying a used 24 foot RV just for their holidays. From their perspective:
1. More room while rolling = less conflict between kids.
2. RV park is better for kids to blow off steam at the end of the day.
3. Much easier to bring enough stuff to keep the kids entertained.
Has had this feature since the first iPhone had a GPS chip. It wasn't flexible enough to remind you when you passed *any* milk store, but tasks could be assigned a location, and you could set a radius for notification.
Wouldn't geeks moving entropy around online also be a PITA to the RIAA enforcers? If lots of people exchange song or movie sized chunks of/dev/random, then you have plausible deniability.
With lidar reconnaissance from airplanes our cities are mapped to sub meter accuracy. Given that the moon has no atmosphere orbiting the moon at airplane elevations should be easy. After that it's a matter of enough orbits, and enough data transmission.
Add to this side scan radar, and you can add a texture map.
I would expect that a 1 meter map of the moon would be cheap.
One of the shuttle missions did a 90 meter SAR map of most of the earth in, I think 9 days. The data quality was awful due to a combination of weather, differential reflection, vegetation, and that sub 90 meter features can have significant effects on a 90 meter pixel.
Convective heat transfer depends on having enough space for the fluid to circulate easily. Every fiber is surrounded by a static boundary layer. Every boundary layer has an adjacent layer where flow is restricted.
It will be a good insulator for the same reason that spun fiberglass is a good insulator,
Note that recently,(a few years) FG insulation has been downgraded, particularly as a ceiling insulation, for high differential temperatures. Turns out that once you get a differential of about 100F across a standard ceiling, you start to get slow convection in the glass. The effective R value is cut in half.
Anyone who has done a reno that included the outer skin will have found dirty fiberglass at the walls base. The wall acts as a column sucking air in at the bottom, and releasing it at the top. This is why detailing that housewrap and that plastic liner is important. Mind you, screw it up one way (house wrap well done, vapour barrier sloppy) and the walls rot from condensed moisture. Screw it up the other way, and you lose energy efficiency. This is why Tyvek is slightly permiable.
What is it going to change? Assuming it doesn't cost the earth to make:
1. A laptop or tablet I can use in full sun. make it waterproof. Finally a decent format for field guides, or for techy field work in general.
2. Wall screen TV without a ruinous power bill. Interactive wall sized touch screens.
3. Artist of the month club. Put up a 4 foot square frame, and have a different Monet painting every day, then next month it's Van Gogh.
4. Live windows. E.g. You have a picture window in your apartment that shows a live very high def picture of an alpine meadow, or the field of view from your favorite satellite.
5. In high heating/cooling climates, have no real windows. Just a camera and a screen.
On a more sinister bend:
6. Make one the size of a license plate, and have it show strange numbers when you are speeding.
7. The equivalent of Dr Who's Magic paper that turns into whatever ID you want.
I was never able to take notes in college. My brain seems to be wired with ONE word processor. It can attach to my ears,or eyes, or fingers.
If I try to write notes, I 'tune out' what the prof is saying. If I look at the power point slide, or study the equation on the blackboard I don't hear what he says. If I pay attention to the prof, while writting, I write gibberish.
My technique was:
Read the text the night before. Sit in the front. Pretend with my entire body language that he was the most fascinating person in the world. (This works. Pretend to be interested, sit like you think an interested person would sit, and you become interested.)
I'd write 2-3 pages of notes per course. Mostly things like his office hours or the names of the grad students we could go to for homework help.
Automation costs. Big time. It is precisely the small guy who can't afford it.
A non-robotic example. I grow trees in containers. So every year I plant about 5000 seedlings into styroblocks. The ones that don't sell after two years move to 2 gallon pots. About 3000 of them. The ones that dont sell as 2 gallon trees move to 10 gallon pots. About 1000 of them.. So every year I transplant about 8000 trees. I use about 3 dump truck loads of potting soil per year.
At present I do this by hand. One scoup or shovel full at a time. The smallest ones take 15 s each, the 2 gallon ones take 30 s each. The 10 gallon ones take 3 min each.
There is a machine out there that can provide a recirculating 'water fall' of soil. It's noisy. It's dusty. And it costs $30,000. It would cost me another 10,000 to provide power to it. This has the potential to cut my time by about 50% not counting breakdowns and maintenance.
A fully automated machine is about 80,000 and requires 4 people to run it, and another crew of 6 to haul the potted plants away. It has to be reset and adjusted every time the soil moisture changes, every time the pot changes, every time the tree being planted changes. It's a great way to work, if you are doing 100,000 poinsettias for the Christmas trade.
Now this is simple stuff. Motor, links, pnuematic/hydraulic acatuators. Everything that moves has very limited degrees of freedom, and few require feedback or sensors.
I don't think that wheel rotation is sufficient for a farmbot, unless the farm is kept perfectly flat. Pocket gopher hill? divot in the sod? Mud puddle? Wet grass? Clump of bunch grass? Area missed by the mower? Wheelbarrow left in the way? Basket of chip mulch? A fence post left where it fell off the truck?
How about weeding? Can a farmbot recognize a weed? No? There goes 25% of my use. Can it walk (roll) an irrigation line, and spot clogged drip emmiters, or replace a broken one? Can it poke a finger into the soil and decide if this block of trees needs watering? And then go and set the water, keeping track of how many places water is currently running so as to not overload the capacity of the system. Can it operate my lawnmower? Run a weed eater, spot a leaking pipe while on the way to do something else. Can it deal with 60 different kinds and sizes of pots, and 80 species of trees?
I have a high school kid who works with me after school. He and I working together set up a new irrigation block. This requires: * Drilling 4 holes with a dirt auger. * Setting 4 fence posts. * Screwing two 12 foot 2x4's to the posts. * Drilling 5 holes for.725 plastic tubing. * Stringing 1240 feet of tubing. * Punching a 0.120 hole every 3 feet in that tubing. * Inserting a dripper into that hole. * Connecting the source ends into a manifold. * Pressuring the system and checking for leaks.
He and I working together did it in about 5 hours. The next week, I marked out where the next one would go, and told him, 'your project'.
The only help he needed was with the auger. The soil was dry there, and it needed both of us leaning on it to get enough down pressure to get the bit to bite.
Automating your income taxes is easy compared to automating a farm worker.
1. Mapmaker pro. This is one of the few map making programs that doesn't cost the earth, and has a reasonable feature set for someone who creates maps for orienteering.
2. Ozi-explorer. This is a decent program for working with maps and the output of GPSs.
3. Access. The closest thing I've found on my Mac is Filemaker, but it doesn't allow the quick and dirty report making. Access isn't a real database (at least not natively) but it sure is handy for anything more complicated than a single flat file.
I currently use a Mac, with windows running in VirtualBox.
Gimp photoshop. Sorry. It isn't there.
Digikam Aperture. This one is close. I lived with digikam for years, but when I got the mac, I tried aperture and found that I liked the interface.
Gnumeric Numbers Excel -- mostly because of function support.
Openoffice Abiword MS Word -- mostly because of documentation.
We have an outside breaker. It's build into our electrical meter. Part of our billing rate is determined by what size breaker we have. I recently got a $40/month bill decrease by getting them to replace the 50A breaker with a 35A breaker.
If we call in a power outage, the first thing they ask, "Have you checked the meter breaker?"
Slashdot Mirror
We have it easier than that. Put everything it a bag. The city sorts it.
MORE:
I can buy a walking trailer (30 tonnes -- 60 cubic yards) of compost for 20 bucks a tonne.
If your city is looking at doing this, have them contact City of Edmonton waste management for details.
Look, we're talking about a small temperature change. Possibly enough to change tundra to tiaga. So instead of dwarf swamp birch and arctic shrub willow, you have black spruce. Whoop-de-do. A hundred year old tree that gives you ONE stud.
The place where you might get a change that passed the tipping point for agriculture would be at the northern edge of current agricultural zones.
Even here, the land just isn't valuable enough to make much work worthwhile.
In the Edmonton, Alberta area bush land within the agricultural region, and not in close proximity to a significant city (Significant = has a farm implement dealership) uncleared bush land goes for 90,000 to 180,000 per quarter section (160 acres) It will typically cost another thousand dollars an acre to clear it of spruce and poplar. Depending on the trees and a local mill this may be recoverable from wood sales.
At that point you can farm it.
This is WITHIN the present ag zone.
On the edge of the ag zone, you likely have a more limited set of crops. Possibly only pasture.
Permafrost is potentially deep -- tens to hundreds of feet. It usually isn't drained worth spit. The moss that grows on top/is frozen inside typically has a pH of around 4. Due to the low pH it has almost no nutrients that are available to 'normal' plants. Can it be built up into soil? Probably. But it's not trivial, and would be vastly expensive in a region that is far from being short of land.
Umm. No.
A dinosaur killer pretty much knocks out higher life.
Most plagues kill off under 90% of the potential victims.
A dinokiller rock will devastate a continent, and provide nuclear winter over most of the rest of the planet. Smaller rocks may leave a hemisphere habitable.
If you aren't in the way of the rock itself, most fatalities will be from starvation and civil unrest.
A disease kills you more directly, alhough in a serious pandemic, civil unrest will also play it's role.
One year after a pandemic, you can still grow crops,
I'm not sure.
1. We spend lots more time inside. We spend far more time in close proximity to each other. If the flu strain has an infections time before overt symptoms show, then it would be vectored quickly through travel.
2. Our medical system is very good at dealing with a small number of victims. A pandemic would overwhelm it. Flu kills through respirtory failure. How many ventilators are there in a hospital? 10? 50? Not a lot of help when you have 20,000 sick people at your door.
3. Announcing the pandemic would likely trigger panic. People would flee the cities, likely carrying the virus with them. If 20% of people are sick, another 20% refuse to go to work for fear of catching it, and a further 20% decide it's time to spend a month at hte lake cottage, then 60% of your work force is absent. The economy stops.
In large 3d buildings, having a solution that goes through walls is a Bad Idea (TM)
A directional or a non-penetrating signal is ideal, especially if it is modulated in a way it is still useful after a bounce.
So you wire a house with a wifi hotspot in each room, that either broadcasts on about 10 GHz with 2 mW, or modulates an LED.
The LED has an advantage. You can see it. So you orient yourself so that your device can see it.
The downside of this sort of thing is that it's not just a 'buy it at Best Buy and plug it in" but that it is infra structure that requires enough smarts to read a 30 page manual and make sense of it.
It will never sell as a consumer item.
If your primary concern is snapshots, then a phone with a 3 MP sensor is adequate. They will take shots that look ok as a 5x8 electronic frame or a web page.
Paper printouts above the snapshot size push the envelope of phone cameras.
The problem with most point and shoot cameras is that you compose using an LCD screen -- difficult to do in full sun. Your hands are less stable than your head, so an eyepiece viewfinder tends to make for less motion blur.
Much of 'decent photographs' is composition, not equipment. One of the best pictures I took was with a Kodak Starmite box camera.
Previous poster commented about getting the entry level DSLRs from either Canon or Nikon. I'll add Olympus to that list. They have one that is weather resistant, and substantially lighter.
The SLR gives you:
* Sharper lenses. Prints 16 x24 that look good are easily doable with most lenses.
* Optical zoom.
* Larger sensor => greater sharpness, better low light behaviour.
* Viewfinder composition.
* Better autofocus.
* Faster response to pushing the shutter. (Important for active subjects like kids and squirrels.)
The Phone camera gives you:
* It's usually with you.
* It's very light weight.
*****
Taking decent pictures is far more than your equipment. Much of good picture taking is artistic, not technical. Google photography tutorial. The second thing is take lots of pictures and throw 90% of them away.
If you go with the DSLR, spend a week with the manual. Read 3-5 pages about a feature set, go out and take 100 pictures using that feature set. Repeat. Doing this will make you familiar with everything that the camera can do.
Look at hundreds of pictures. Which are good? Why? What should be different.
The bigger problem if we use enough geothermal to freeze the upper mantle: Plate tectonics grinds to a halt and in a few million years all the continents erode down to tidal flats.
My brother is a prof in microbiology at New Mexico State. Every two years he taught the introductory genetics course. He said that it was a course that he had to relearn each time. The material in the first two weeks (roughly equivalent to what you get in high school) wouldn't have changed much, but everything else was a whole new ball game. It would take him a couple months to decide on a text, and then he still would photocopy a dozen journal articles for the course.
The best option IMHO would be that your license was valid for ALL releases of the book, but you could choose what release or even include multliple releases of certain modules.
I'm not so much worried about redacted stuff as I am about fashions in teaching. The 4th edition of Dirr's "Propagation guide to Woody Ornamentals" is a solid technical manual. The 7th edition is a pretty garden book with 90% of the nitty-gritty details gone.
I respectfully disagree with some of Ms. Stover's points.
Overall there seems to be some confusion between "Renewable" "Zero Impact" and "Expandable indefinitely"
Some of this confusion is in the public mind. I'll agree that many people consider "renewable" to mean "until the sun grows cold" Meanwhile there are some low impact resources that do run out after a few decades.
Yes, even renewable sources have a cost of operation. That does not mean they are a bad idea.
Let's take another look:
1. The Blythe solar project is expected to use 600 acre feet of water per year. To put that in perspective that is the amount of water to irrigate 120 acres of tomatoes in California's San Joachin valley. I live near a 2 GW coal fired power plant. For cooling they have a 3 square mile pond. In our climate a dugout evaporates about 4 feet a year. So just the evaporative losses alone account for roughly 7200 acre feet per year. Given that the pond is about half uncovered even in midwinter, I suspect that the additional evaporation from it being hotter water than a farmer's dugout raises this evaporative amount considerably.
Yes, water is more scarce in the desert. However compare the water use by the power plant compared to the water used by either industry or the residents that will use that power.
I'll agree the solar PV power is a marginally green technology at this time.
Report card:
Renewable: Long term.
Impact: Water use -- on the order of 1/10 that of conventional power.
Expansion: Moderate. Very large expansion can alter local climate and heat balance. (Solar thermal is overall darker than native desert, so the area will experience an overall temperature increase.
Geothermal:
Geothemal can use injected water, but depending on the nature of the hot rock formation, they will cool off the rocks. There is some work being done on drilling in very hot rock. This would mean that, like some classes of water well, each well has a finite life span.
Report card:
Renewable: Each installation has a limited lifespan. Use of directional drilling technology may allow each installation to harvest the heat from several cubic miles of crust.
Impact: Requires reinjection of water. The use of air cooled condensers (Like at the Blythe project above) would reduce this considerably.
Expansion: Natural sites fairly rare. Quite expandable when we can drill hot rock.
Wind Power.
Citing the rare earth magnets as a non-recoverable cost is disingenuous. They would be reused in the next turbine. And they aren't that rare. They are just difficult to separate. The concrete is not much concrete. Many cities have at least 8000 miles of sidewalk..
Report card:
Renewable: Indefinately.
Impact: Cost of construction is significant. Given their relatively short lives, it may make sense to use steel pylons for foundations. My understanding is that they have short lives because the tech keeps improving, and that after 3-4 years it is worth replacing a 2 MW unit with a 5 MW unit because they already have the site permits, and the power line right of way. There is a good market for used wind turbines. Good sites are rare, and usually not convienient to consumption. Requires extensive power grid infra-structure increases.
Expansion: Lots of room for expansion. Windfarms can co-exist with other agricultural use.
Biomass:
Argueably the best way to use biomass is with the residue of regular crops. A good case can be made for extracting syngas from any biomass feed stock, and returning the charcoal to the land to create terra pretta. Some research needs to be done to see if this is viable in temperate climates. There are methods for fermenting celluose using a bacterial process for breaking the cellulose into sugar, then yeast to make alchohol. This is a much more complex process than distallation for syngas.
I have also seen the numbers (Scientific American, many years ago) that for a Tennessee based power plant t
My reading of the summary says that they claim that is opaque in one direction and transparent in the other.
Consider the following thought experiment:
Assume that this material works the same way for far-infrared as it does for visible light.
In a well insulated cylinder place a sheet of this material across the interior of the cylinder so that light can pass to the left, but not to the right.
Now the material in the right end of the cylinder is emmitting infra-red radiation. It can pass through the material. This warms up the left side, and cools off the right side.
Now we have a temperature difference, so we can run a heat engine. Voila! perpetual motion.
Now if the material doesn't do this with room temperature radiation, then we have to put it in a red hot environment. Will the material still work at those temps?
I agree syslog locally, and to a remote host. Finding differences between the two logs (for a given host) is your first clue that something is amiss.
OpenBSD at least has a method that a file can be marked appendable, but not rewritable. This is enforced by the kernel, and cannot be reset without rebooting the computer. And if your computer is set up properly it doesn't set up any external routes until after it has gone into secure mode.
The proposal is to have a chain of events, so that the hash of the previous message is used as part of encryption of the next one. Which seems to me to mean that overwriting any byte early in the file would make the rest of the file unreadable.
This is one I'd reject for contravening the KISS principle. The complexity doesn't gain you much of anything.
Swapping platters is not trivial. Putting a faux label with the old serial number on another drive would be far easier.
Much of the expense comparison depends on the size/newness of the RV. If your primary goal is travel -- new campground every night, driving 400-600 miles per day then a large RV will cost enough more in fuel to eat up the motel savings. But a small RV is still a reasonable proposition.
I know of several retired folks that have the big RV's towing a small car. Their pattern is an annual cycle, spending two to six weeks in one spot. Their family are scattered over the country.
Another advantage: When you visit, your hosts don't have to make a room up for you. You are fairly self contained. This reduces a lot of the "Fish & visitors..." effect.
I have a niece who has 5 kids. They aren't rich, but are comfortable. They are considering buying a used 24 foot RV just for their holidays. From their perspective:
1. More room while rolling = less conflict between kids.
2. RV park is better for kids to blow off steam at the end of the day.
3. Much easier to bring enough stuff to keep the kids entertained.
Has had this feature since the first iPhone had a GPS chip. It wasn't flexible enough to remind you when you passed *any* milk store, but tasks could be assigned a location, and you could set a radius for notification.
Doesn't have to be that big. I recall seeing figures that anything below 1 RPM was reasonable.
F = v^2/R
v=pi d/T (T=period)
F = 4r pi^2 / T^2
r = FT^2/4 pi
r = 10 * 3600 / 40
r = 900 meters. That's doable as a simple dumbbell shape.
If 2 rpm is acceptable (see wiki article on artificial gravity) then 225 meters is the radius.
Wouldn't geeks moving entropy around online also be a PITA to the RIAA enforcers? If lots of people exchange song or movie sized chunks of /dev/random, then you have plausible deniability.
100 meter accuracy isn't amazing.
With lidar reconnaissance from airplanes our cities are mapped to sub meter accuracy. Given that the moon has no atmosphere orbiting the moon at airplane elevations should be easy. After that it's a matter of enough orbits, and enough data transmission.
Add to this side scan radar, and you can add a texture map.
I would expect that a 1 meter map of the moon would be cheap.
One of the shuttle missions did a 90 meter SAR map of most of the earth in, I think 9 days. The data quality was awful due to a combination of weather, differential reflection, vegetation, and that sub 90 meter features can have significant effects on a 90 meter pixel.
Convective heat transfer depends on having enough space for the fluid to circulate easily. Every fiber is surrounded by a static boundary layer. Every boundary layer has an adjacent layer where flow is restricted.
It will be a good insulator for the same reason that spun fiberglass is a good insulator,
Note that recently,(a few years) FG insulation has been downgraded, particularly as a ceiling insulation, for high differential temperatures. Turns out that once you get a differential of about 100F across a standard ceiling, you start to get slow convection in the glass. The effective R value is cut in half.
Anyone who has done a reno that included the outer skin will have found dirty fiberglass at the walls base. The wall acts as a column sucking air in at the bottom, and releasing it at the top. This is why detailing that housewrap and that plastic liner is important. Mind you, screw it up one way (house wrap well done, vapour barrier sloppy) and the walls rot from condensed moisture. Screw it up the other way, and you lose energy efficiency. This is why Tyvek is slightly permiable.
What is it going to change? Assuming it doesn't cost the earth to make:
1. A laptop or tablet I can use in full sun. make it waterproof. Finally a decent format for field guides, or for techy field work in general.
2. Wall screen TV without a ruinous power bill. Interactive wall sized touch screens.
3. Artist of the month club. Put up a 4 foot square frame, and have a different Monet painting every day, then next month it's Van Gogh.
4. Live windows. E.g. You have a picture window in your apartment that shows a live very high def picture of an alpine meadow, or the field of view from your favorite satellite.
5. In high heating/cooling climates, have no real windows. Just a camera and a screen.
On a more sinister bend:
6. Make one the size of a license plate, and have it show strange numbers when you are speeding.
7. The equivalent of Dr Who's Magic paper that turns into whatever ID you want.
Still the best document creation package I've found.
I was never able to take notes in college. My brain seems to be wired with ONE word processor. It can attach to my ears,or eyes, or fingers.
If I try to write notes, I 'tune out' what the prof is saying. If I look at the power point slide, or study the equation on the blackboard I don't hear what he says. If I pay attention to the prof, while writting, I write gibberish.
My technique was:
Read the text the night before.
Sit in the front.
Pretend with my entire body language that he was the most fascinating person in the world. (This works. Pretend to be interested, sit like you think an interested person would sit, and you become interested.)
I'd write 2-3 pages of notes per course. Mostly things like his office hours or the names of the grad students we could go to for homework help.
Automation costs. Big time. It is precisely the small guy who can't afford it.
A non-robotic example. I grow trees in containers. So every year I plant about 5000 seedlings into styroblocks. The ones that don't sell after two years move to 2 gallon pots. About 3000 of them. The ones that dont sell as 2 gallon trees move to 10 gallon pots. About 1000 of them.. So every year I transplant about 8000 trees. I use about 3 dump truck loads of potting soil per year.
At present I do this by hand. One scoup or shovel full at a time. The smallest ones take 15 s each, the 2 gallon ones take 30 s each. The 10 gallon ones take 3 min each.
There is a machine out there that can provide a recirculating 'water fall' of soil. It's noisy. It's dusty. And it costs $30,000. It would cost me another 10,000 to provide power to it. This has the potential to cut my time by about 50% not counting breakdowns and maintenance.
A fully automated machine is about 80,000 and requires 4 people to run it, and another crew of 6 to haul the potted plants away. It has to be reset and adjusted every time the soil moisture changes, every time the pot changes, every time the tree being planted changes. It's a great way to work, if you are doing 100,000 poinsettias for the Christmas trade.
Now this is simple stuff. Motor, links, pnuematic/hydraulic acatuators. Everything that moves has very limited degrees of freedom, and few require feedback or sensors.
I don't think that wheel rotation is sufficient for a farmbot, unless the farm is kept perfectly flat. Pocket gopher hill? divot in the sod? Mud puddle? Wet grass? Clump of bunch grass? Area missed by the mower? Wheelbarrow left in the way? Basket of chip mulch? A fence post left where it fell off the truck?
How about weeding? Can a farmbot recognize a weed? No? There goes 25% of my use. Can it walk (roll) an irrigation line, and spot clogged drip emmiters, or replace a broken one? Can it poke a finger into the soil and decide if this block of trees needs watering? And then go and set the water, keeping track of how many places water is currently running so as to not overload the capacity of the system. Can it operate my lawnmower? Run a weed eater, spot a leaking pipe while on the way to do something else. Can it deal with 60 different kinds and sizes of pots, and 80 species of trees?
I have a high school kid who works with me after school. He and I working together set up a new irrigation block. This requires: .725 plastic tubing.
* Drilling 4 holes with a dirt auger.
* Setting 4 fence posts.
* Screwing two 12 foot 2x4's to the posts.
* Drilling 5 holes for
* Stringing 1240 feet of tubing.
* Punching a 0.120 hole every 3 feet in that tubing.
* Inserting a dripper into that hole.
* Connecting the source ends into a manifold.
* Pressuring the system and checking for leaks.
He and I working together did it in about 5 hours. The next week, I marked out where the next one would go, and told him, 'your project'.
The only help he needed was with the auger. The soil was dry there, and it needed both of us leaning on it to get enough down pressure to get the bit to bite.
Automating your income taxes is easy compared to automating a farm worker.
1. Mapmaker pro. This is one of the few map making programs that doesn't cost the earth, and has a reasonable feature set for someone who creates maps for orienteering.
2. Ozi-explorer. This is a decent program for working with maps and the output of GPSs.
3. Access. The closest thing I've found on my Mac is Filemaker, but it doesn't allow the quick and dirty report making. Access isn't a real database (at least not natively) but it sure is handy for anything more complicated than a single flat file.
I currently use a Mac, with windows running in VirtualBox.
Gimp photoshop. Sorry. It isn't there.
Digikam Aperture. This one is close. I lived with digikam for years, but when I got the mac, I tried aperture and found that I liked the interface.
Gnumeric Numbers Excel -- mostly because of function support.
Openoffice Abiword MS Word -- mostly because of documentation.
We have an outside breaker. It's build into our electrical meter. Part of our billing rate is determined by what size breaker we have. I recently got a $40/month bill decrease by getting them to replace the 50A breaker with a 35A breaker.
If we call in a power outage, the first thing they ask, "Have you checked the meter breaker?"
MacGyver