If I read de Laval nozzle equation correctly an increase in the combustion chamber pressure has minimal impact on the exhaust velocity (going from 260 Bar to 300 Bar has less than 1% improvement).
Combustion chamber temperature is a far better indication of efficiency of the engine and has a far more direct impact of exhaust velocity than pressure.
Credit where credit due - design requires 170 metric tonnes of force, test fire got 172 metric tonnes (design works as expected).
Apparently the Great Barrier Reef has moved in and out from the Australian coast line as the sea levels have risen and fallen with each ice age. From memory the difference in sea levels is about 30 meters.
This reef could very well be a remanent coral reef from the last ice age and has evolved / adjusted to continue surviving at about 30 meters depth (which could also be the limit of light penetrating the ocean).
The largest ships (oil tankers / cruise ships) have a draft between 12 to 20 meters so there is sufficient clearance that if these reefs are indeed in 30+ meters depth of water that no-one would of paid any attention.
I would second the recommendation of releasing a viable "proof of concept" for public comments.
Twenty years ago (how time flies) I was part of a group of people who dealt with parallel port devices for Linux. A couple of newbies joined the Linux parallel port mailing list and started spouting about bus theory for sharing the parallel port for multiple device drivers. For the most part the participants on the mailing list were more interested in the practical side of getting their favorite parallel storage device working with Linux reliably than computer science theory. I responded to the newbies with a "put up or shut-up", in this case "please provide a header file of the routines that you would expect a parallel port sharing module to require". Dutifully the newbie responded over night with prototype header file and the next weekend (and about half a dozen kernal panics later) I coded up a variant of the lp & ppa driver with the relevant glue logic. This was posted to the mailing list and suddenly everyone jumped on the code and started porting existing drivers to the new architecture which shortly became known as parport.
I must give additional credit to the newbie (I have forgotten the persons name) but he did get stuck into kernal hacking once the parport prototype was released. It is hell a lot easier to start modifying an existing code base than to start from scratch.
Bulk of the consumer grade UPS are based off sealed lead acid - fairly idiot proof but only moderate charge capacity, limited peak draw capacity and limited life (normally the battery capacity has seriously degraded after two years of continuous service).
Making the battery user replaceable would be a big step in the right direction.
Shifting to Lithium Ion cells (preferably the iron phosphate variant) and applying a little de-rating will significantly improve the situation (requires a charge management circuit but these can be easily be sourced). The manufacturers' data sheets state to charge lithium ion cells to 4.2 volts per cell, keep the charge limited to 4.1 or even 4.0 volts per cell will dramatically increase the life of the cells (leave this as an exercise for the reader to research).
If you want to make the equipment "industrial rated" then component ratings need to be reviewed. Capacitors are available in various voltage ratings however if you want the equipment to last 10 years in +100F/+40C conditions then the voltage rating needs to be nearly double the normal operating voltage (there is a study done/sponsored by one of the US military branches on longevity and component ratings).
There is some fairly heavy engineering required on the power side of stuff and I don't believe ESR has yet to wrap his head around all the issues. Perhaps that is why he has put the call out for assistance.
This is the result of a postal auction of supply versus demand. There was suddenly a drop of nearly 500 MW and the other generators are trying to ramp up to fill the void.
The quoted price is where power companies are willing to turn off entire suburbs. For what it is worth it was a very hot day in Melbourne and there would have been a serious backlash if a power company blacked out a suburb to save a couple of thousand dollars (a bit like Malaysian Airlines taking the Ukraine route to save about $1000 in jet fuel).
If you were a power company - at what point do you start cutting customers off?
With the exception of one team this is largely a practical academic exercise.
The Hyperloop concept could be found in a physics text book circa 1990 (or earlier) as a thought exercise of how rail systems could achieve speeds equal or faster than air travel. Practical considerations of the cost to build such a large scale system (for example LA to NY) would be approaching a national commitment approaching that of the "Man on the Moon" of the late 60s (~2.5% of the USA national GDP for 10 years - effectively 1 in 40 people).
This competition is similar to the solar car challenges of the 1990s / 2000s where it exists to expose the engineering students to the large number of compromises needed to achieve the desired goal (weight, power, size, cost, etc). Ability to find an optimal solution while addressing the multitude of competing constraints is a key talent to be able to succeed in any engineering discipline - especially aerospace (talent identification for Space-X?).
Back to the issue of Hyperloop - we are probably 20 years away from a working system with a number of technologies still yet to be developed. Toyota released the Prius in 1997 as result of their development efforts towards a fully electric car. At the time the technology for a fully electric car was "not ready yet" and the release of a hybrid car was a bridging technology. As a development platform towards fully electric cars the hybrids have successfully filled its original role as a number of manufacturers sell plug-in electric cars (we have moved a step down the path to mainstream electric vehicle transport).
The rolling stock for Hyperloop is only one part of the problem (my guess is this will be resolved within 5 years) - the other monster that needs to be tamed is building the track and associated infrastructure cost effectively. For comparison: Railway sidings are $1-$2 million/mile, Highway $4-$10 million/mile, Light rail $35 million/mile, High speed rail (California) $56 million/mile.
What is required is an X-Prize style competition for building the Hyperloop track as the cost of the rolling stock is likely to pale into insignificance.
Handling the pressure is relatively easy (a soda can needs to contain 3 atmospheres of pressure).
The suit is a glorified party balloon with an astronaut inside. Stopping the suit from going pop when it rubs against something inside the capsule is the hard part.
These suits do not protect against temperature extremes, for that you end up with the inch thick layer of insulation to prevent the astronaut being deep fried while in the sun or snap frozen while in the shade.
Pretty much all fossil fuels have some level of sulfur (if not - it commands a price premium and unlikely to be used for electrical power generation).
The sulfur would end up in the stack as sulfur dioxide with is likely to be scrubbed out as sodium sulfite (not sulfate). Sulfites salts have various health issues for some people.
I am struggling to see a market for the sodium bicarbonate unless this is a variation of the Solvay process (sodium chloride + calcium carbonate => sodium carbonate + calcium chloride), unfortunately the Solvay process is not without waste products.
Prairie is basically flat land which means there should be access roads in the area for firefighting. Containment lines are typically created by back burning (starting a fire such that it burns back into the wind) from the access roads. The access road acts as a fire break for creating these couple of hundred yard wide fuel dead zones.
A quad bike and a drip torch is going to be just as quick but far more cost effective than a drone in such a situation.
Change the geography to a more mountainous region such as Washington state then you are comparing a drone to a manned helicopter at which point the drone wins hands down.
The path of a hurricane is somewhat unpredictable (been known to turn 90 degrees for no apparent reason).
The bigger issue which is harder to address is making homes that can "largely survive" being hit by a hurricane. The biggest issue is the junk flying around due to the strong winds (and storm surge if you are near the water). Once a building starts to disintegrate it provides the wind with ammunition for taking out other buildings.
In Australia when a cyclone is heading towards your community and potentially make land fall within 48 hours there is a whole pile of things that kick in for preparation (food, water, fuel, tie down and clean up - most people will be sent home by work during this period). At about six hours it is a case of bunker down and wait for it to go overhead.
Better prediction will reduce the amount of communities put on alert and associated disruption but unlikely to reduce the damage in affected areas (for that you need better building codes and people willing to take appropriate measures).
Do a bit of research and you should get the price down.
I have a friend who is a type I diabetic with a number of complications (occasional dizzy spells) which rules out being able to drive a car or ride a regular bike.
I was able to source a kit adult tricycle for about AUD$300 and a bike conversion kit from http://dillengerelectricbikes.... for AUD$700 (replace the front hub). There are some shipping costs which I haven't included, assembly took about a day and a half (one day for the trike, 4 hours for the conversion kit). I have come across adult trikes are used by the maintenance crews on industrial sites.
In hindsight given that it was a trike I could of gone sealed lead acid battery conversion kit (AUD$360 - includes electric hub, battery, controller and all the components). Providing that you are moderately competent with hand tools such as a spanner and hex keys you could replicate what I did for AUD$800 / USD$600.
Normally there is some time between neutron capture and actual nuclear fission (I have heard a figure of 15 minutes). This means that even if the control rods are slammed in when the power transmission lines were cut the previous heat load would still be generated for a period of time. Often this means resorting to drastic measures to reduce the neutron flux to zero ASAP (certain salts are added to cooling loops which achieve this but requires a good flush to get rid of).
Controlled shutdown means the reactor can be restarted in "a couple of hours" Emergency shutdown means the reactor can be restarted in "a couple of weeks"
There is a chart which shows the optimal temperature for an office is around 23'C (Google "HVAC comfort chart"), this is the temperature which has the widest acceptable range for humidity that people find comfortable.
Evaporative cooling brings the air temperature down by increasing the humidity of the air. The issue is that to achieve sufficient cooling the humidity increases beyond the comfort zone without bringing the temperature down sufficiently.
What would be interesting is a two stage evaporative cooling that does not require mechanical assistance. In a two stage system the first stage provides net cooling without humidifying the air used by the second stage. It results in cooler air with less humidity.
Depending on the refrigerant used it is possible that the condenser temperature (the bit exposed to the outside air) exceeded the critical point of the gas at which point it is impossible to tell the difference between liquid or gas. The trouble is phase change cooling works best (most efficient) the closer to the critical point you can go but not past it.
The second problem is the condenser pressure would increase with increasing ambient air temperature. In the past this was enough to stall the compressor motors on a hot day.
My guess is they went for a system with a high efficiency that should work for 99.9% of the time, that last 0.1% is the 8 hours of the year when the temperature is above 42'C (normally for Perth it is normally only an hours before the sea breeze kicks in and drops the temperature by at least 5'C). This time the temperature went up and stayed up for a period of time.
First issue is will this material be suitable for wind speeds of 100 miles per hour? I live in a coastal city where wind gusts reach that speed and that is "a bad winter storm".
Did they think to look at the mechanical ventilators used on glass houses? These are driven by the thermal expansion of wax (incompressible fluids can exert a very large force)
For the cost of the proposed surface perhaps they should be looking at optimal spacing of solar panels (solar panels have a higher initial cost but have a long term financial benefit as opposed to the alternative roof material). On a tile roof the installation requires an air gap between the panels and the roof, this gap has cooling benefits however panels are often placed edge-to-edge preventing any hot air trapped from escaping.
Page 41: In 1999, the Commonwealth of Virginia tasked the Virginia Department of State Police to study the need for State standards for recapped vehicle tires. The occurrence of tire debris along Virginia’s highways gave rise to the perception that retread truck tires were to blame. The study would determine whether there was any substance to the perception.
Page 43: The primary conclusion from the Virginia study “revealed that the quality of materials and methods of producing retreaded tires are not major factors in the problem of tire debris along the highways” (Commonwealth of Virginia, 2000). The primary study objective was not proved through the evidence collected and analyzed. Of the tire debris items analyzed, only one case was directly linked to manufacturing error in the retread process.
Another interesting bit of information can be found on page 48, that a survey of unservicable tires that 31% were original with the remainder being retreads (mostly one or two retreads).
The perverse bit is the more times a tire can be retreaded the more likely the road debris is going to be from a retread tire however the overall amount of road debris should drop.
This will probably come down to whether this feature can squeeze another retread out of the tire casing - that is where the savings are going to be.
The 1% extra saving in fuel will be lost in the noise (that is - too difficult to measure).
I was reading a DOT report on "Commercial Medium Tire Debris Study" (DOT HS 811 060) and an inference that approximately 50% of tire failures are due to belt separation and that 50% of the probable cause is due to under inflation (both refer to "all tire failures").
Quoting the report: This scenario is confirmed by Kreeb et al. (2003) who noted “The act of tire pressure maintenance is labor- and time-intensive. An 18-wheeled vehicle can take from 20 to 30 minutes to check all of the tires and inflate perhaps 2 or 3 tires that may be low on air. To complete this task once each week on every tractor and trailer becomes a challenge for many fleet operators. As a result, tires are often improperly inflated.”
Not really - you would need professional indemnity insurance.
The insurance is based on risk of a claim (more copies sold / bigger the premium, could be priced on a fixed price per copy), the impact of damage (just make sure that the license terms exclude indirect consequental damages).
The risk side of the equation can be reduced by using appropriate development structures (code reviews, etc).
This could improve the quality of the industry long term but there will be some pain getting there...
You can not sue a door or window manufacturer for failure of your action (leaving the door / window open).
You should be able to successfully able to sue a door / window manufacturer for failing to provide the request product (i.e. seal the opening).
That then hits the ugly question of what is "reasonable". Did the manufacturer provide a reasonable product that provided the expected level of security?
Another system just off the coast of Fremantle, Australia (west coast of Australia)
http://www.carnegiewave.com/index.php?url=/ceto/ceto-overview
Does not produce electricity directly but very high pressure sea water which can then be used directly in a desalination plant and the waste run through a hydraulic turbine to generate mechanical / electrical energy.
Given that wave energy is nearly constant around the clock, generating fresh water rather than electricity does have its advantages, doubly so in a very dry part of the world.
ZombieEngineer
Might be something in there that help. Specifically display standards and alarm rationalisation ("every alarm should have a unique action", if there is nothing the operator on shift can do about an alarm it should be journaled).
This could feasibly be used to make a practical air conditioner by having a segmented disk shape block that allows air to pass through.
Outside air would pass through one half of the disk that is currently energised (the electric field orders the polymer and thus releases heat).
The inside air would pass through the other half that is currently not energised (the relaxation of the electric field allows the material to absorb heat).
The disk rotates with segments shifting between the outside / inside halves, the electric field is applied by a simple electric comutation.
This is not a true "no moving parts" system but it has the potential to be an order of magnitude quieter than the current air conditioning units.
Safety control systems in the chemical industry have been used for 20+ years.
These systems have:
- redundant CPU modules (which can be hot plugged)
- redundant IO modules (which can be hot plugged)
- redundant communication systems
- self diagnostics (can detect a failed output transistor)
- internal diagnostics (CPU voting to detect failed CPU core)
- standard algorithms for redundant transmitters
Shutting down is the "safer option" however there is still risks (such as thermal stressing pipework). It is a lesser of the two evils problem.
This stuff is bread & butter for the chemical industry, there are a number of control companies that refuse to deal with the nuclear industry due to the requirement for unlimited indementy.
ZombieEngineer
Slashdot Mirror
Probably easier to use classic PV panels and a separate electrolysis cell.
There are electrolysis cells that can directly provide 120-200 bar hydrogen without an additional compressor.
https://en.wikipedia.org/wiki/...
If I read de Laval nozzle equation correctly an increase in the combustion chamber pressure has minimal impact on the exhaust velocity (going from 260 Bar to 300 Bar has less than 1% improvement).
Combustion chamber temperature is a far better indication of efficiency of the engine and has a far more direct impact of exhaust velocity than pressure.
Credit where credit due - design requires 170 metric tonnes of force, test fire got 172 metric tonnes (design works as expected).
Apparently the Great Barrier Reef has moved in and out from the Australian coast line as the sea levels have risen and fallen with each ice age. From memory the difference in sea levels is about 30 meters.
This reef could very well be a remanent coral reef from the last ice age and has evolved / adjusted to continue surviving at about 30 meters depth (which could also be the limit of light penetrating the ocean).
The largest ships (oil tankers / cruise ships) have a draft between 12 to 20 meters so there is sufficient clearance that if these reefs are indeed in 30+ meters depth of water that no-one would of paid any attention.
I would second the recommendation of releasing a viable "proof of concept" for public comments.
Twenty years ago (how time flies) I was part of a group of people who dealt with parallel port devices for Linux. A couple of newbies joined the Linux parallel port mailing list and started spouting about bus theory for sharing the parallel port for multiple device drivers. For the most part the participants on the mailing list were more interested in the practical side of getting their favorite parallel storage device working with Linux reliably than computer science theory. I responded to the newbies with a "put up or shut-up", in this case "please provide a header file of the routines that you would expect a parallel port sharing module to require". Dutifully the newbie responded over night with prototype header file and the next weekend (and about half a dozen kernal panics later) I coded up a variant of the lp & ppa driver with the relevant glue logic. This was posted to the mailing list and suddenly everyone jumped on the code and started porting existing drivers to the new architecture which shortly became known as parport.
I must give additional credit to the newbie (I have forgotten the persons name) but he did get stuck into kernal hacking once the parport prototype was released. It is hell a lot easier to start modifying an existing code base than to start from scratch.
ZombieEngineer
Bulk of the consumer grade UPS are based off sealed lead acid - fairly idiot proof but only moderate charge capacity, limited peak draw capacity and limited life (normally the battery capacity has seriously degraded after two years of continuous service).
Making the battery user replaceable would be a big step in the right direction.
Shifting to Lithium Ion cells (preferably the iron phosphate variant) and applying a little de-rating will significantly improve the situation (requires a charge management circuit but these can be easily be sourced). The manufacturers' data sheets state to charge lithium ion cells to 4.2 volts per cell, keep the charge limited to 4.1 or even 4.0 volts per cell will dramatically increase the life of the cells (leave this as an exercise for the reader to research).
If you want to make the equipment "industrial rated" then component ratings need to be reviewed. Capacitors are available in various voltage ratings however if you want the equipment to last 10 years in +100F/+40C conditions then the voltage rating needs to be nearly double the normal operating voltage (there is a study done/sponsored by one of the US military branches on longevity and component ratings).
There is some fairly heavy engineering required on the power side of stuff and I don't believe ESR has yet to wrap his head around all the issues. Perhaps that is why he has put the call out for assistance.
Try $14,000/MW-hr => $14/kW-hr
This is the result of a postal auction of supply versus demand. There was suddenly a drop of nearly 500 MW and the other generators are trying to ramp up to fill the void.
The quoted price is where power companies are willing to turn off entire suburbs. For what it is worth it was a very hot day in Melbourne and there would have been a serious backlash if a power company blacked out a suburb to save a couple of thousand dollars (a bit like Malaysian Airlines taking the Ukraine route to save about $1000 in jet fuel).
If you were a power company - at what point do you start cutting customers off?
With the exception of one team this is largely a practical academic exercise.
The Hyperloop concept could be found in a physics text book circa 1990 (or earlier) as a thought exercise of how rail systems could achieve speeds equal or faster than air travel. Practical considerations of the cost to build such a large scale system (for example LA to NY) would be approaching a national commitment approaching that of the "Man on the Moon" of the late 60s (~2.5% of the USA national GDP for 10 years - effectively 1 in 40 people).
This competition is similar to the solar car challenges of the 1990s / 2000s where it exists to expose the engineering students to the large number of compromises needed to achieve the desired goal (weight, power, size, cost, etc). Ability to find an optimal solution while addressing the multitude of competing constraints is a key talent to be able to succeed in any engineering discipline - especially aerospace (talent identification for Space-X?).
Back to the issue of Hyperloop - we are probably 20 years away from a working system with a number of technologies still yet to be developed. Toyota released the Prius in 1997 as result of their development efforts towards a fully electric car. At the time the technology for a fully electric car was "not ready yet" and the release of a hybrid car was a bridging technology. As a development platform towards fully electric cars the hybrids have successfully filled its original role as a number of manufacturers sell plug-in electric cars (we have moved a step down the path to mainstream electric vehicle transport).
The rolling stock for Hyperloop is only one part of the problem (my guess is this will be resolved within 5 years) - the other monster that needs to be tamed is building the track and associated infrastructure cost effectively. For comparison: Railway sidings are $1-$2 million/mile, Highway $4-$10 million/mile, Light rail $35 million/mile, High speed rail (California) $56 million/mile.
What is required is an X-Prize style competition for building the Hyperloop track as the cost of the rolling stock is likely to pale into insignificance.
Handling the pressure is relatively easy (a soda can needs to contain 3 atmospheres of pressure).
The suit is a glorified party balloon with an astronaut inside. Stopping the suit from going pop when it rubs against something inside the capsule is the hard part.
These suits do not protect against temperature extremes, for that you end up with the inch thick layer of insulation to prevent the astronaut being deep fried while in the sun or snap frozen while in the shade.
Pretty much all fossil fuels have some level of sulfur (if not - it commands a price premium and unlikely to be used for electrical power generation).
The sulfur would end up in the stack as sulfur dioxide with is likely to be scrubbed out as sodium sulfite (not sulfate). Sulfites salts have various health issues for some people.
I am struggling to see a market for the sodium bicarbonate unless this is a variation of the Solvay process (sodium chloride + calcium carbonate => sodium carbonate + calcium chloride), unfortunately the Solvay process is not without waste products.
112 MPH when crossing the 1/4 mile mark.
The article has a photo of the summary sheet from the drag strip showing all the statistics.
Prairie is basically flat land which means there should be access roads in the area for firefighting. Containment lines are typically created by back burning (starting a fire such that it burns back into the wind) from the access roads. The access road acts as a fire break for creating these couple of hundred yard wide fuel dead zones.
A quad bike and a drip torch is going to be just as quick but far more cost effective than a drone in such a situation.
Change the geography to a more mountainous region such as Washington state then you are comparing a drone to a manned helicopter at which point the drone wins hands down.
The path of a hurricane is somewhat unpredictable (been known to turn 90 degrees for no apparent reason).
The bigger issue which is harder to address is making homes that can "largely survive" being hit by a hurricane. The biggest issue is the junk flying around due to the strong winds (and storm surge if you are near the water). Once a building starts to disintegrate it provides the wind with ammunition for taking out other buildings.
In Australia when a cyclone is heading towards your community and potentially make land fall within 48 hours there is a whole pile of things that kick in for preparation (food, water, fuel, tie down and clean up - most people will be sent home by work during this period). At about six hours it is a case of bunker down and wait for it to go overhead.
Better prediction will reduce the amount of communities put on alert and associated disruption but unlikely to reduce the damage in affected areas (for that you need better building codes and people willing to take appropriate measures).
Do a bit of research and you should get the price down.
I have a friend who is a type I diabetic with a number of complications (occasional dizzy spells) which rules out being able to drive a car or ride a regular bike.
I was able to source a kit adult tricycle for about AUD$300 and a bike conversion kit from http://dillengerelectricbikes.... for AUD$700 (replace the front hub). There are some shipping costs which I haven't included, assembly took about a day and a half (one day for the trike, 4 hours for the conversion kit). I have come across adult trikes are used by the maintenance crews on industrial sites.
In hindsight given that it was a trike I could of gone sealed lead acid battery conversion kit (AUD$360 - includes electric hub, battery, controller and all the components). Providing that you are moderately competent with hand tools such as a spanner and hex keys you could replicate what I did for AUD$800 / USD$600.
Sounds like this is a "preventative measure".
Normally there is some time between neutron capture and actual nuclear fission (I have heard a figure of 15 minutes). This means that even if the control rods are slammed in when the power transmission lines were cut the previous heat load would still be generated for a period of time. Often this means resorting to drastic measures to reduce the neutron flux to zero ASAP (certain salts are added to cooling loops which achieve this but requires a good flush to get rid of).
Controlled shutdown means the reactor can be restarted in "a couple of hours"
Emergency shutdown means the reactor can be restarted in "a couple of weeks"
Burnt once, twice shy...
There is a chart which shows the optimal temperature for an office is around 23'C (Google "HVAC comfort chart"), this is the temperature which has the widest acceptable range for humidity that people find comfortable.
Evaporative cooling brings the air temperature down by increasing the humidity of the air. The issue is that to achieve sufficient cooling the humidity increases beyond the comfort zone without bringing the temperature down sufficiently.
What would be interesting is a two stage evaporative cooling that does not require mechanical assistance. In a two stage system the first stage provides net cooling without humidifying the air used by the second stage. It results in cooler air with less humidity.
ZombieEngineer
Depending on the refrigerant used it is possible that the condenser temperature (the bit exposed to the outside air) exceeded the critical point of the gas at which point it is impossible to tell the difference between liquid or gas. The trouble is phase change cooling works best (most efficient) the closer to the critical point you can go but not past it.
The second problem is the condenser pressure would increase with increasing ambient air temperature. In the past this was enough to stall the compressor motors on a hot day.
My guess is they went for a system with a high efficiency that should work for 99.9% of the time, that last 0.1% is the 8 hours of the year when the temperature is above 42'C (normally for Perth it is normally only an hours before the sea breeze kicks in and drops the temperature by at least 5'C). This time the temperature went up and stayed up for a period of time.
First issue is will this material be suitable for wind speeds of 100 miles per hour?
I live in a coastal city where wind gusts reach that speed and that is "a bad winter storm".
Did they think to look at the mechanical ventilators used on glass houses? These are driven by the thermal expansion of wax (incompressible fluids can exert a very large force)
For the cost of the proposed surface perhaps they should be looking at optimal spacing of solar panels (solar panels have a higher initial cost but have a long term financial benefit as opposed to the alternative roof material). On a tile roof the installation requires an air gap between the panels and the roof, this gap has cooling benefits however panels are often placed edge-to-edge preventing any hot air trapped from escaping.
You are not alone in that view...
Link to referenced study report:
http://www.nhtsa.gov/DOT/NHTSA/NRD/Multimedia/PDFs/Crash%20Avoidance/2008/811060.pdf
Page 41:
In 1999, the Commonwealth of Virginia tasked the Virginia Department of State Police to study the need for State standards for recapped vehicle tires. The occurrence of tire debris along Virginia’s highways gave rise to the perception that retread truck tires were to blame. The study would determine whether there was any substance to the perception.
Page 43:
The primary conclusion from the Virginia study “revealed that the quality of materials and methods of producing retreaded tires are not major factors in the problem of tire debris along the highways” (Commonwealth of Virginia, 2000). The primary study objective was not proved through the evidence collected and analyzed. Of the tire debris items analyzed, only one case was directly linked to manufacturing error in the retread process.
Another interesting bit of information can be found on page 48, that a survey of unservicable tires that 31% were original with the remainder being retreads (mostly one or two retreads).
The perverse bit is the more times a tire can be retreaded the more likely the road debris is going to be from a retread tire however the overall amount of road debris should drop.
This will probably come down to whether this feature can squeeze another retread out of the tire casing - that is where the savings are going to be.
The 1% extra saving in fuel will be lost in the noise (that is - too difficult to measure).
I was reading a DOT report on "Commercial Medium Tire Debris Study" (DOT HS 811 060) and an inference that approximately 50% of tire failures are due to belt separation and that 50% of the probable cause is due to under inflation (both refer to "all tire failures").
Quoting the report:
This scenario is confirmed by Kreeb et al. (2003) who noted “The act of tire pressure maintenance is labor- and time-intensive. An 18-wheeled vehicle can take from 20 to 30 minutes to check all of the tires and inflate perhaps 2 or 3 tires that may be low on air. To complete this task once each week on every tractor and trailer becomes a challenge for many fleet operators. As a result, tires are often improperly inflated.”
ZombieEngineer
Not really - you would need professional indemnity insurance.
The insurance is based on risk of a claim (more copies sold / bigger the premium, could be priced on a fixed price per copy), the impact of damage (just make sure that the license terms exclude indirect consequental damages).
The risk side of the equation can be reduced by using appropriate development structures (code reviews, etc).
This could improve the quality of the industry long term but there will be some pain getting there...
You can not sue a door or window manufacturer for failure of your action (leaving the door / window open).
You should be able to successfully able to sue a door / window manufacturer for failing to provide the request product (i.e. seal the opening).
That then hits the ugly question of what is "reasonable". Did the manufacturer provide a reasonable product that provided the expected level of security?
Another system just off the coast of Fremantle, Australia (west coast of Australia) http://www.carnegiewave.com/index.php?url=/ceto/ceto-overview Does not produce electricity directly but very high pressure sea water which can then be used directly in a desalination plant and the waste run through a hydraulic turbine to generate mechanical / electrical energy. Given that wave energy is nearly constant around the clock, generating fresh water rather than electricity does have its advantages, doubly so in a very dry part of the world. ZombieEngineer
The chemical processing industry have been working together for at least 15 years on related topics.
http://www.asmconsortium.net/deployment/guidelines/Pages/default.aspx
Might be something in there that help.
Specifically display standards and alarm rationalisation ("every alarm should have a unique action", if there is nothing the operator on shift can do about an alarm it should be journaled).
ZombieEngineer
This could feasibly be used to make a practical air conditioner by having a segmented disk shape block that allows air to pass through.
Outside air would pass through one half of the disk that is currently energised (the electric field orders the polymer and thus releases heat).
The inside air would pass through the other half that is currently not energised (the relaxation of the electric field allows the material to absorb heat).
The disk rotates with segments shifting between the outside / inside halves, the electric field is applied by a simple electric comutation.
This is not a true "no moving parts" system but it has the potential to be an order of magnitude quieter than the current air conditioning units.
ZombieEngineer
Safety control systems in the chemical industry have been used for 20+ years. These systems have: - redundant CPU modules (which can be hot plugged) - redundant IO modules (which can be hot plugged) - redundant communication systems - self diagnostics (can detect a failed output transistor) - internal diagnostics (CPU voting to detect failed CPU core) - standard algorithms for redundant transmitters Shutting down is the "safer option" however there is still risks (such as thermal stressing pipework). It is a lesser of the two evils problem. This stuff is bread & butter for the chemical industry, there are a number of control companies that refuse to deal with the nuclear industry due to the requirement for unlimited indementy. ZombieEngineer