There are more important things than wireless internet access. Instead of stomping on a valuable service such as GPS, total available bandwidth can be easily increased by decreasing spacing between towers and thus making more frequent re-use of the assigned frequencies.
You're correct that a lot of long haul trucking can be replaced by electrified railroads, but LWATCDR is correct in stating that it would cost billions of dollars and take a number of years. The Southern California Regional Rail Authority held a series of meetings in 1990-92 on a proposal to electrify the freight railroads in Southern California and the estimated cost at that time was 4 billion $. FWIW, I attended several of these meetings.
The high fixed cost problem has been the stumbling block for RR electrification in the US even though the pioneering long distance electrifications were in the US - 1907 for the New Haven and 1916 for the Milwaukee. Since 1940, it has been generally cheaper in the US to generate electricity on board the locomotive than with central power stations. This may change if the current price differential between oil and natural gas holds up.
Electric Railroads require a reliable source of base load power. Neither wind or solar qualifies as reliable base load generation.
Simply put, LightSquared should have known that use of high power terrestial base stations could adversely affect GPS receivers and they should have made an effort to see if a work-around was possible before acquiring rights to the frequency bands. Since they didn't, LightSquared management have probably opened themselves up to shareholder lawsuits.
The original allocation for the LightSquared frequencies was for satellite based transmitters and it is up to LightSquared to prove that shifting to terrestial transmitters will not cause harmful interference.
It's the customary unit of measure in the US for water/irrigation districts as the most common unit for describing land area in the US is the acre. Converting to metric would require updating millions of legal titles and the benefit from doing so is not considered to be worth the cost.
Or for that matter that efficient generators ANYWHERE need rare earth magnets. In the end, almost all power generation needs the same kind of generator, the only difference is what makes them spin and how efficient you want them to be.
Large central station generators (actually alternators...) have been achieving 98 to 99% efficiency for several decades now using copper and electrical steel (no Neodymium). A larger rotor allows for more copper, which reduces the percentage of the alternators output power needed for generating the field. With a wind turbine sized alternator, the power required to maintain the field can approach 5% of the rated output, hence the use of permanent magnets (especially since the turbine is rarely producing rated output). Also note that making concrete for the foundations for the wind turbines does involve a lot of CO2 emissions - look up cement kilns.
FWIW, the NdFeB magnet material was originally developed at General Motors.
This demonstrates that talks about "total power" or "total radiation" are misleading.
Really poor analogies. What you are referring to is energy concentrated in a small part of the body as opposed to the whole body. The scanners distribute the energy over the whole body and any breakdown with the scanning mechanism will be immediately evident in the image. Also remember when dealing with total doses on the milli-rem level, it doesn't make much of difference whether the dose occurred during a microsecond or over a day. Starting around 25 rem or so, there is a substantial difference in getting the dose in much less than a day as opposed to a couple of years.
The point is that ANY ionizing radiation increases the risk of cancer, and therefore, statistically speaking, over a large population these scanners WILL kill people, its just a matter of how many lives are we willing to sacrifice for the facade of security.
Considering that the dose from a scan is equivalent to a few minutes of flying on a geomagnetically quiet day, more people are getting killed from cancer induced by flying than by getting scanned. If you're that concerned about additional radiation, you should be checking for any unusual geomagnetic activity before flying, especially at high geomagnetic latitudes or maybe just give up flying altogether.
Infrequent flyers will often have more to worry about the radiation dose from their own homes from radon and normally occurring radioactive materials in many building materials.
The application calls for a storage system that can provide up to 6MW for about 20 to 30 seconds. My gut reaction is that ultracaps would be a better choice than flywheels, the discharge rate is close to optimal for ultracaps and the cycle life would probably be much higher for ultracaps (especially since the caps would rarely be fully discharged). In addition, the control scheme would be much simpler, the caps would be floating on the third rail supply, not needing the power conversion electronics and motor/alternator on flywheels.
While not caused by the aircrew, the plane was essentially brought down by a former PSA employee using his badge to get by security. This happened while PSA was in the process of being folded into UseLess Air (USAir).
My recollection was that the XT came out in early 1983. Hell, the 8086/88 weren't announced till sometime in 1978 and SCP built their first 8086 board set in 1979. Anyway, the period from about 1990 to 2002 was when the big speedups took place - i.e. from when the 25MHz 486 was the hot machine to the netburst architecture.
Sounds like you are in what used to be Northern Ohio Telephone Co territory. NOTC was bought by GTE in 1968, the phone portion of GTE merged with Bell Atlantic to form Verizon in 1999, then Verizon spinning off a bunch of their business the last few years.
That's been true only since the last DC residential service got converted to AC. Prior to WW2, there were pockets of 50 Hz (Southern Cal Edison converted to 60 Hz in '47-'48), 25Hz, 133Hz and a few other odd frequencies.
The links convert AC to DC and then back to AC in order to eliminate the synchronous connection. My recollection is that the conversions process was close to 99% efficient. A more recent alternative to DC links is GE's phase shifting transformer which allows transfer of reactive as well as real power.
I take you're not familiar with The Registers system of units. Volume can be measured in Bulgarian airbags, Bulgarian funbags, Olympic swimming pools, etc.
The original topic was the power grid, not residential wiring standards. As far as I know, the US grid has far more high voltage AC lines (i.e. 765kV and above) and HVDC lines than Europe.
I'd like to know which country has an electric grid that makes the US grid look primitive. Japan still has the 50/60Hz split, the US grid has been 60Hz only since 1948 (albeit there are remnants of 25HZ systems for railway/electrochemical use). Haven't heard anything about Europe that makes it superior to the US. China might have an edge due to the newness of their infrastructure.
There were two top priority space related projects in the US in the mid 1950's. One was to develop an ICBM, with the Atlas becoming operational 1960-61. The other was to develop photo reconnaissance satellites as aerial reconnaissance was risky (Gary Powers) and provided limited coverage.
von Braun's team could have launched a satellite in January 1956, but Eisenhower gave strict orders that they were not permitted to do so. One reason was that if the Soviets were first to launch a satellite, they would have no basis for objecting to overflights by US satellites.
A rocket can be anything driven by a non-air-breathing reaction engine. These objects can range in size from a bottle rocket to a Saturn 5 (or larger).
A missile is typically an unmanned weapon that travels through air or space that is directed to a target, though common usage often excludes projectiles launched from guns and unguided rockets bearing warheads. There are two broad types of modern missiles, guided and ballistic. Guided missiles use aerodynamic surfaces to adjust the course of the missile between launch and arrival at target, these can be either air-breathing or rocket propelled. Ballistic missiles are guided by some sort of thrust vectoring while the motors are burning and unguided after burnout.
A rocket that is used to place satellites in orbit is often called a booster or launcher. The Atlas series were originally designed as InterContinental Ballistic Missiles (ICBM), but the later versions were strictly intended as boosters.
I'm old enough to remember hearing and reading about Cape Canaveral before it became Cape Kennedy. Makes sense to go back to the old place name and renaming the facility. IIRC, I Dream of Jeannie was one of the first TV shows to use a Titan Gemini launch instead of an Atlas Mercury launch for the generic space launch shot.
Fahrenheit is also based on water - zero degrees is the lowest freezing point for a concentrated brine solution. Converting to degrees Rankine is also a simple matter of addition. Do recall that R = 1.8 * K.
Not to mention your weird "Letter" size which is inexplicably the default in all your word processing programs when all the rest of the world uses A4.
This probably won't matter much in a few years - documents will be prepared to fit a standard display size.
Funny thing about "Letter" size - it is exactly 215.9 by 279.4 mm, granted the 215.9mm could be rounded up to 216mm without anyone noticing, but rounding 279.4 to either 279 or 280 will cause people to notice. The dimensions for A4 are only approximations as the "true" dimensions are irrational numbers.
As for reactors - pipe and tubing sizes have been standardized for decades.
Another reason the US has not converted is that almost all of the land titles are expressed in feet (and decimal thereof) - where the foot is defined as 1/66th of a Gunther's chain. Similarly, a statute mile is 80 Gunther's chains long, and an acre is 10 square chains.
Funny thing was that a decimal system of units was Thomas Jefferson's idea. He first proposed a foot that would have been 1/10,000th of a nautical mile and then proposed a unit of length based on the second's rod - the length of a pendulum that would have a period of exactly one second at 45 degrees of longitude - took the world some 170 years to define the meter in such a way that it could be generated in any properly equipped laboratory.
Don't get me started on units of temperature - where the "scientific" Celsius has zero based on some ill-defined phase change in water and 100 based on the vapor pressure of water being equal to some arbitrary pressure. Real scientific units of temperature are electron-volts or frequency as defined by Boltzmann's and Planck's constants.
Light travels 0.984 feet in one nanosecond - too bad that the definition of the foot is so well entrenched that it couldn't be adjusted to equal the distance light traveled in one nano-second (call it the light-foot). This would be a much more logical unit of length than the meter, which is a mis-measurement of one ten-millionth the distance from the north pole to the equator at the longitude of Paris. For mass, I would like to see something on the order of 10E26 hydrogen atoms, etc.
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There are more important things than wireless internet access. Instead of stomping on a valuable service such as GPS, total available bandwidth can be easily increased by decreasing spacing between towers and thus making more frequent re-use of the assigned frequencies.
So the only people who are qualified to be journalists are extreme left wing hacks with huge axes to grind?
A monoculture in journalism is even more dangerous than a monoculture in operating systems.
You're correct that a lot of long haul trucking can be replaced by electrified railroads, but LWATCDR is correct in stating that it would cost billions of dollars and take a number of years. The Southern California Regional Rail Authority held a series of meetings in 1990-92 on a proposal to electrify the freight railroads in Southern California and the estimated cost at that time was 4 billion $. FWIW, I attended several of these meetings.
The high fixed cost problem has been the stumbling block for RR electrification in the US even though the pioneering long distance electrifications were in the US - 1907 for the New Haven and 1916 for the Milwaukee. Since 1940, it has been generally cheaper in the US to generate electricity on board the locomotive than with central power stations. This may change if the current price differential between oil and natural gas holds up.
Electric Railroads require a reliable source of base load power. Neither wind or solar qualifies as reliable base load generation.
Simply put, LightSquared should have known that use of high power terrestial base stations could adversely affect GPS receivers and they should have made an effort to see if a work-around was possible before acquiring rights to the frequency bands. Since they didn't, LightSquared management have probably opened themselves up to shareholder lawsuits.
The original allocation for the LightSquared frequencies was for satellite based transmitters and it is up to LightSquared to prove that shifting to terrestial transmitters will not cause harmful interference.
It's the customary unit of measure in the US for water/irrigation districts as the most common unit for describing land area in the US is the acre. Converting to metric would require updating millions of legal titles and the benefit from doing so is not considered to be worth the cost.
Or for that matter that efficient generators ANYWHERE need rare earth magnets. In the end, almost all power generation needs the same kind of generator, the only difference is what makes them spin and how efficient you want them to be.
Large central station generators (actually alternators...) have been achieving 98 to 99% efficiency for several decades now using copper and electrical steel (no Neodymium). A larger rotor allows for more copper, which reduces the percentage of the alternators output power needed for generating the field. With a wind turbine sized alternator, the power required to maintain the field can approach 5% of the rated output, hence the use of permanent magnets (especially since the turbine is rarely producing rated output). Also note that making concrete for the foundations for the wind turbines does involve a lot of CO2 emissions - look up cement kilns.
FWIW, the NdFeB magnet material was originally developed at General Motors.
This demonstrates that talks about "total power" or "total radiation" are misleading.
Really poor analogies. What you are referring to is energy concentrated in a small part of the body as opposed to the whole body. The scanners distribute the energy over the whole body and any breakdown with the scanning mechanism will be immediately evident in the image. Also remember when dealing with total doses on the milli-rem level, it doesn't make much of difference whether the dose occurred during a microsecond or over a day. Starting around 25 rem or so, there is a substantial difference in getting the dose in much less than a day as opposed to a couple of years.
The point is that ANY ionizing radiation increases the risk of cancer, and therefore, statistically speaking, over a large population these scanners WILL kill people, its just a matter of how many lives are we willing to sacrifice for the facade of security.
Considering that the dose from a scan is equivalent to a few minutes of flying on a geomagnetically quiet day, more people are getting killed from cancer induced by flying than by getting scanned. If you're that concerned about additional radiation, you should be checking for any unusual geomagnetic activity before flying, especially at high geomagnetic latitudes or maybe just give up flying altogether.
Infrequent flyers will often have more to worry about the radiation dose from their own homes from radon and normally occurring radioactive materials in many building materials.
The application calls for a storage system that can provide up to 6MW for about 20 to 30 seconds. My gut reaction is that ultracaps would be a better choice than flywheels, the discharge rate is close to optimal for ultracaps and the cycle life would probably be much higher for ultracaps (especially since the caps would rarely be fully discharged). In addition, the control scheme would be much simpler, the caps would be floating on the third rail supply, not needing the power conversion electronics and motor/alternator on flywheels.
While not caused by the aircrew, the plane was essentially brought down by a former PSA employee using his badge to get by security. This happened while PSA was in the process of being folded into UseLess Air (USAir).
My recollection was that the XT came out in early 1983. Hell, the 8086/88 weren't announced till sometime in 1978 and SCP built their first 8086 board set in 1979. Anyway, the period from about 1990 to 2002 was when the big speedups took place - i.e. from when the 25MHz 486 was the hot machine to the netburst architecture.
Sounds like you are in what used to be Northern Ohio Telephone Co territory. NOTC was bought by GTE in 1968, the phone portion of GTE merged with Bell Atlantic to form Verizon in 1999, then Verizon spinning off a bunch of their business the last few years.
That's been true only since the last DC residential service got converted to AC. Prior to WW2, there were pockets of 50 Hz (Southern Cal Edison converted to 60 Hz in '47-'48), 25Hz, 133Hz and a few other odd frequencies.
The links convert AC to DC and then back to AC in order to eliminate the synchronous connection. My recollection is that the conversions process was close to 99% efficient. A more recent alternative to DC links is GE's phase shifting transformer which allows transfer of reactive as well as real power.
I take you're not familiar with The Registers system of units. Volume can be measured in Bulgarian airbags, Bulgarian funbags, Olympic swimming pools, etc.
The original topic was the power grid, not residential wiring standards. As far as I know, the US grid has far more high voltage AC lines (i.e. 765kV and above) and HVDC lines than Europe.
I'd like to know which country has an electric grid that makes the US grid look primitive. Japan still has the 50/60Hz split, the US grid has been 60Hz only since 1948 (albeit there are remnants of 25HZ systems for railway/electrochemical use). Haven't heard anything about Europe that makes it superior to the US. China might have an edge due to the newness of their infrastructure.
There were two top priority space related projects in the US in the mid 1950's. One was to develop an ICBM, with the Atlas becoming operational 1960-61. The other was to develop photo reconnaissance satellites as aerial reconnaissance was risky (Gary Powers) and provided limited coverage.
von Braun's team could have launched a satellite in January 1956, but Eisenhower gave strict orders that they were not permitted to do so. One reason was that if the Soviets were first to launch a satellite, they would have no basis for objecting to overflights by US satellites.
A rocket can be anything driven by a non-air-breathing reaction engine. These objects can range in size from a bottle rocket to a Saturn 5 (or larger).
A missile is typically an unmanned weapon that travels through air or space that is directed to a target, though common usage often excludes projectiles launched from guns and unguided rockets bearing warheads. There are two broad types of modern missiles, guided and ballistic. Guided missiles use aerodynamic surfaces to adjust the course of the missile between launch and arrival at target, these can be either air-breathing or rocket propelled. Ballistic missiles are guided by some sort of thrust vectoring while the motors are burning and unguided after burnout.
A rocket that is used to place satellites in orbit is often called a booster or launcher. The Atlas series were originally designed as InterContinental Ballistic Missiles (ICBM), but the later versions were strictly intended as boosters.
I'm old enough to remember hearing and reading about Cape Canaveral before it became Cape Kennedy. Makes sense to go back to the old place name and renaming the facility. IIRC, I Dream of Jeannie was one of the first TV shows to use a Titan Gemini launch instead of an Atlas Mercury launch for the generic space launch shot.
Fahrenheit is also based on water - zero degrees is the lowest freezing point for a concentrated brine solution. Converting to degrees Rankine is also a simple matter of addition. Do recall that R = 1.8 * K.
Not to mention your weird "Letter" size which is inexplicably the default in all your word processing programs when all the rest of the world uses A4.
This probably won't matter much in a few years - documents will be prepared to fit a standard display size.
Funny thing about "Letter" size - it is exactly 215.9 by 279.4 mm, granted the 215.9mm could be rounded up to 216mm without anyone noticing, but rounding 279.4 to either 279 or 280 will cause people to notice. The dimensions for A4 are only approximations as the "true" dimensions are irrational numbers.
As for reactors - pipe and tubing sizes have been standardized for decades.
Another reason the US has not converted is that almost all of the land titles are expressed in feet (and decimal thereof) - where the foot is defined as 1/66th of a Gunther's chain. Similarly, a statute mile is 80 Gunther's chains long, and an acre is 10 square chains.
Funny thing was that a decimal system of units was Thomas Jefferson's idea. He first proposed a foot that would have been 1/10,000th of a nautical mile and then proposed a unit of length based on the second's rod - the length of a pendulum that would have a period of exactly one second at 45 degrees of longitude - took the world some 170 years to define the meter in such a way that it could be generated in any properly equipped laboratory.
Don't get me started on units of temperature - where the "scientific" Celsius has zero based on some ill-defined phase change in water and 100 based on the vapor pressure of water being equal to some arbitrary pressure. Real scientific units of temperature are electron-volts or frequency as defined by Boltzmann's and Planck's constants.
Light travels 0.984 feet in one nanosecond - too bad that the definition of the foot is so well entrenched that it couldn't be adjusted to equal the distance light traveled in one nano-second (call it the light-foot). This would be a much more logical unit of length than the meter, which is a mis-measurement of one ten-millionth the distance from the north pole to the equator at the longitude of Paris. For mass, I would like to see something on the order of 10E26 hydrogen atoms, etc.