Monday, June 20, 2011

EADS is working on an aerospace plane that would connect Paris to Tokyo in 2:30 - LeMonde.fr

EADS  is  working  on  an  aerospace plane  that  would  connect  Paris  to Tokyo in 2:30   



Proposed space plane for EADS.
Proposed space plane for EADS. AFP / -

In 2050, passengers may board a space plane that will travel to Tokyo from Paris in 2 h 30 min and will not pollute the planet because it will fly in the stratosphere.  In any case, it is the bold project of EADS, the large European aerospace group.
Since  the  tragic death  of  Concorde,  the  idea  of an  airplane  of  high  speed  seemed  abandoned, manufacturers seeking to make their devices lighter and therefore consume less kerosene. The super sonic aircraft had became unaffordable.  But on the eve of the Paris Air Show, EADS, owner of Airbus, has unveiled his plan Zehst ( "Zero Emission High Speed ​​Transport " ), a hypersonic plane - even faster than supersonic - which aims is zero CO2 emissions.
"The aircraft of the future as I imagine Zehst" said Jean Botti , Mr. "innovation" of EADS.A model of 4 meters of the plane, whose shape is surprisingly close to the supersonic Concorde, will be presented at Le Bourget, high mass of the aircraft which opened Monday to professionals and the general public Thursday.A step in the future when Airbus announced nearly two years behind two versions of its new A350 long-haul, including a time required to equip the A350-1000 with an engine more efficient.
BIOFUELS seaweed
The Zehst contains all the ingredients for the best novel of science fiction.Takeoff is fairly standard, except that its engines are fueled with biofuels from algae, is Jean Botti, Chief Operating Officer Technology and Innovation at EADS.Once it took a bit of altitude, it switches to engine type rocket.And here, the motors do not work with algae but hydrogen and oxygen.They are "totally clean and emit only water vapor" .
The air then rises up to 32 km altitude, cruising altitude.A conventional airplane flying at 10,000 feet.For the passenger does not feel the effect "big eight" , seat tilt.The advantage of this time, "you pollute more, you are in the stratosphere, pollution is transparent to us" , argues Jean Botti.For landing, the pilot cuts the engine and begins its descent in a glider before landing by delivering conventional engines of the aircraft.
MARKETING TO 2050
For Mr. Botti, "the solution (green) is on the edge of space. It's not a plane, not a rocket is a rocket plane commercial" .The Zehst, with a capacity of 50 to 100 people, is currently a draft.While EADS has a schedule: a first demonstrator around 2020, for commissioning by 2050.At that time, space and aviation landscape has certainly changed a lot, however, especially with the advent of emerging countries.And EADS was created 10 years ago only.Therefore difficult to project to such deadlines.However, a spokesman for EADS, the project has a good chance of success, the necessary technologies are already developed.
Rocket engines already exist: Astrium, EADS Space, the space tourism develops.The algae-based fuels are ready, he said.In addition, the Zehst is thought together with Japan and with the Directorate General of Civil Aviation (DGCA) French.Despite these projects mad scientist, Jean Botti recognizes that research can not advanced by small steps: first think of commercial aircraft based on environmentally sustainable technologies, for 20 to 25 people.Then increase to 50, 100 and then 200 people, a medium-capacity traditional mail.
EADS is working on an aerospace plane that would connect Paris to Tokyo in 2:30 - LeMonde.fr

Wednesday, June 15, 2011

Summary of algebra - Topics in precalculus

 



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1

The Formal Rules of Algebra

ALGEBRA  is a method of written calculations.  Now what is a calculation? It is replacing one set of symbols with another? In arithmetic we may replace the symbols  '2 + 2'  with the symbol  '4.' In algebra we may replace  'a + (−a)'  with '0.'
a + (−a) = 0.
A formal rule, then, shows how an expression written in one form may be rewritten in a different form.  The = sign means  "may be rewritten as"  or  "may be replaced by."
If p and q are statements (equations), then a rule
If p, then q,
or equivalently
p implies q,
means:  We may replace statement p with statement q.  For example,
x + a = b  implies  x = b − a.
That means that we may replace the statement  'x + a = b'  with the statement  'x = b − a.'
Algebra depends on how things look.  We can say, then, that algebra is a system of formal rules.  The following are what we are permitted to write.
(See the complete course, Skill in Algebra.)
a = a Identity
 
If a = b, then b = a. Symmetry
 
If a = b  and  b = c, then a = c.   Transitivity
a + b  =  b + a
 
a· b  =  b· a
  15.  The multiplicative inverse or reciprocal of  a,
  5.    symbolized as  1
a
 (a 0)
a·  1
a
  =   1
a
· a   =  1
  The reciprocal of   p
q
 is  q
p
.
a
b
  =   a·  1
b
   a
b
 = −  a
b
. a
  b
 = −  a
b
. a
b
 =  a
b
.
0
a
  =  0.   a
0
  =  No value.   0
0
  =  Any number.
m(a + b) = ma + mb The distributive rule/
  Common factor
 
(xa)(xb) = x² − (a + b)x + ab  
  Quadratic trinomial
 
(a ± b)² = a² ± 2ab + b² Perfect square trinomial
 
(a + b)(ab) = a² − b² The difference of
  two squares
 
(a ± b)(a² ab + b²) = a³ ± b³     The sum or difference of
  two cubes
If      If   
 
  a  =  b,   a  =  b,
 
then      then   
 
        a + c  =  b + c.   ac  =  bc.
If    
 
  a  =  b,
 
then    
 
  a  =  b.
If    
 
  a  <  b,
 
then    
 
  a  >  b.
If     If  
 
    x + a  =  b,         xa  =  b,
 
then     then  
  x  =  ba.     x  =  a + b.
***
If     If  
 
    ax  =  b,        x
   a
 =  b,
 
then     then  
  x  =  b
a
  x  =  ab.
17.  Change of sense when solving an inequality
If    
 
  ax  < b,    
 
then    
 
  x  > − b
a
.
18.  Absolute value
If  |x| = b,  then  x = b  or  x = −b.
If  |x| < b  then  −b < x < b.
If  |x| > b  (and b > 0), then  x > b  or  x < −b.
19.  The principle of equivalent fractions
x
y
 =  ax
ay
 
and symmetrically,
ax
ay
 =  x
y
We may multiply both the numerator and denominator by the same factor; we may divide both by the same factor.
20.  Multiplication of fractions
a
b
·    c
d
 =   ac
bd
 
a ·    c
d
 =   ac
d
21.  Division of fractions (Complex fractions)
Division is multiplication by the reciprocal.
22.  Addition of fractions
a
c
 +  b
c
 =  a + b
   c
Same denominator
 
a
b
 +   c
d
 =  ad + bc
   bd
Different denominators with
no common factors
 
 a 
bc
 +   e 
cd
 =  ad + be
   bcd
Different denominators with
common factors
The common denominator is the LCM of denominators.
23.  The rules of exponents
aman  =  am+n   Multiplying or dividing
 
am
an 
 =  am−n   powers of the same base
 
 
(ab)n  =  anbn   Power of a product of factors
 
 
(am)n  =  amn   Power of a power
24.  The definition of a negative exponent
an  =   1 
an
25.  The definition of exponent 0
a0 = 1
26.  The definition of the square root radical
The square root radical squared produces the radicand.
27.  Equations of the form  a² = b
If
a²  =  b,
 
then
a  =  ±.
28.  Multiplying/Factoring radicals
 = 
 
and symmetrically,
 
 = 
log  x
y
  =  log x  −  log y.
log 1 = 0.   logbb = 1.



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Wednesday, June 1, 2011

Ten Reasons Why You’ll Really Enjoy Owning an Electric Car (Page 3)

Ten Reasons Why You’ll Really Enjoy Owning an Electric Car



2011-05-24T

Taken in Bristol, UK. Photograph taken by Phil Bambridge. Used with Permission.

Taken in Bristol, UK. Photograph taken by Phil Bambridge. Used with Permission.

Enlarge Photo

This month has seen a lot of witty articles about the pros and cons of electric transportation, usually titled ‘Ten reasons why electric cars...’ followed by: "suck" or "don’t work" or "will change your life" ... or even reasons why it’s not worth arguing about it at all.

The focus has been largely centered around the environmental and political merits of electric cars.

While I’d be the first to admit that was why I got into ‘electrics' in the first place, after a year of owning a pair, I’ve mellowed out a little. Now I've found 10 entirely new reasons that you’d enjoy owning and driving an electric car if you had one.

1. Torque: the revenge of the muscle car

Back in the Sixties and Seventie, big hairy-chested men plied the roads of America in big, torque-y Muscle Cars. They didn’t need no stinking SUV with ‘heated, seats’, 'sat nav’ and, 'carpets' to prove how tough they were, just several hundred foot-pounds of torque and a 0-to-60 time of under 5 seconds.

1977 Ford Pinto Cruising Wagon, photo by Wikipedia user Vegavairbob

1977 Ford Pinto Cruising Wagon, photo by Wikipedia user Vegavairbob

Enlarge Photo

That was the domain of the American Muscle Car: “powwwwerrrrrrr," as some would put it. Of course, October 1973 killed it dead. The first oil crisis did muscle cars in, and instead of 400 cu in. and 300 ft-lbs of torque, we soon got the Ford Pinto Cruising Wagon and waved goodbye to 200 of those ‘torques’.

Torque is what produces that shove in the back that only displacement used to bring. These days, see your local EV for those torgues, because that’s where they're all found now.

Better yet, we get access to all of them, right off the line. Yes, the Tesla Roadster will light up the rear end like the best of them. Even the modest MINI E and the 2011 Nissan Leaf will spin a wheel if you’re rough with them.

They may look all cute and cuddly, and sound like they couldn’t hurt a fly but, ladies and gentlemen, take a firm hold of the wheel of an electric car. You have been warned.

2010 Chumpcar Texas Motor Speedway, Friday Garage Photos

2010 Chumpcar Texas Motor Speedway, Friday Garage Photos

Enlarge Photo

2. Clean garage

The modern car represents the pinnacle of fossil-fuel combustion technology, and while they don’t usually drip oil like your dad’s car did, they still have to emit some junk out of the back.

The thing is, that happens the most when they’re cold or when they’re not feeling well, 'cause their smog trap is full or their cat’ is ill.

And, that’s usually when they’re tucked up in the garage at home. Ever stood in the garage while someone starts up a cold car? Want to stay there long? My local Tesla

3. Always full dealer has a workshop in a former art gallery. Yes, they’re that clean, and they certainly don’t soil their own bed.

Each morning I get up and unplug the car. At first it was odd, having to plug in each night and disconnect every morning, but it quickly melted into the background of the daily routine.

To be honest I can’t even remember unplugging this morning... I hope there isn’t a power cord trailing out of the side right now.

And it means that every morning, I start with a "full tank". No worries

4. Very smooth

Small cars are often criticized for lacking the smoothness of a large luxo-barge. What if I could give you a small car that could make its way through the congested streets of the city, in the rush hour, with the effortless smoothness of the finest Jaguar?

Well, see your local EV dealer--that's how they all are. The first thing that hit my friend who tried a Tesla in New York City was, “Wow, it’s so easy to drive in traffic, so smooth.”

There’s no clutch, no gear change, and no auto-transmission torque-converter-drag nonsense. Setting off in slow traffic is all about resting your foot on the accelerator. Just like those big electric trains, you look out of the window and think, “Oh, we’re moving."

5. Waiting with heat and air

It’s so hot today, the paint is peeling off the faces of the cosmetic sales assistants coming out of the local department store. No, it’s so cold today the ice on the car looks like my refrigerator at home... the one that needed defrosting last year... and still does.

Either way, I’m outside waiting to pick up my daughter, in the car. The engine is off, I’m not idling, the car isn’t shaking, and I can read my book. And, I’m lovely and cool or toasty.

The heating and cooling in my car runs any time I like. Just like the HVAC at home, it doesn’t need an engine to make it go.

6. Maintenance, Lack of

Annual service... “One, two, er, three, four. OK, sir, they’re all still attached and they all have plenty of tread left. Be on your way then.”

Yes, that’s pretty much it. Once a year the Tesla Roadster (or any EV) should be checked over. Tesla will even come to your house to do that. That 3,000-mile oil change? ‘pfft!'

7. Cold weather warmup

It’s early morning and it’s minus something-or-other outside. I back the car out of the garage, turn it around, and warm air is already puffing out of the vents.

If you want to test out cold weather ‘EV’ life in a regular car, take a 4KW electric fan heater, put it in your car and turn it on. That’s what electric car heat is like: lovely

8. They aren't bothered by the cold

‘Crank, crank crank, put, put, put, dag.... dag.... dag, dag, dag, dag, dag, dag, dag....” We’ve all had an old car at some point in our lives; it’s a rite of passage.

It was always the cold and the wet that got them. Seldom did they fail on a warm summer's day, when the inevitable walk to the bus stop might have been pleasant.

Now, I can’t tell you an electric car won’t have electrical problems. But, I can tell you that the cold and the wet doesn’t register. In fact, to a very tiny degree, electric motors prefer to be colder. Getting the mixture right and warming up your catalytic converter in an Arctic winter will never trouble you.

heffner ford gt 007heffner ford gt 007

Enlarge Photo

9. Silence

My house sits between a pair owned by petrol-heads. Ironic right? On one side, a neighbor has the venerable Ford GT. On the other, he has enough old school American iron to open a museum. On a Sunday morning my ears ring to the sound of rumbling exhausts and my nose reels to the stench of half burnt gasoline.

Now, I’m all for preserving history, but after living with the turbine-like whoosh from the back of the Tesla--the one that signals the moment the horizon gets ripped towards me like a tablecloth in a cheap magician's trick--the ‘daga, daga, daga’ of old iron has become just that, old iron.

The sound of a gas engine has all the charisma of a bunch of sweaty carpenters nailing up an outhouse. It doesn’t compare to the ‘Ooos’ and ‘Aaahs’ of spectators as the Tesla whispers past. It’s just...noise.

10. They were good in 1910 and they’re still good today

At the turn of the century, in answer to the horrific problem caused by inner-city transportation, electric cars were introduced as a cheap, quiet, non-polluting alternative to replace the horse. I expect you know I mean the turn of the 20th century, right, not this last one?

New York City in the late 1800s was by all accounts an unpleasant place. The exhaust gas and particulate emissions of horses were so bad that the city had to employ an army of workers with large wagons to move the output of these beasts from the city.

It was a round-the-clock effort as, the moment they stopped or the rain came down, the roads became treacherous rivers of effluent and disease. Gasoline cars were found to frighten the horses and create even more noise, plus similar, if different, types pollution.

Electrics were the answer and, for a short time--before the auto industry convinced us that noise and smell was a good thing--they ruled the roads of New York City. Electric taxi cabs plied the roads, swapping batteries as needed at local depots. Theatergoers booked their cabs in advance, and riding in an ‘Electric’ was the height of social standing.

Today, we’re on our way back. First came hybrid taxi cabs, next will be some electric trucks, and hopefully we’ll see the return of electric cabs. Next time you’re in gridlock in a big city, pause for a moment and imagine what it would be like if all the cars were silent, clean electric vehicles.

+++++

So there’s my Top 10. My message is simple: Forget the environment for a moment, forget our troops fighting to secure the precious oil that so many burn so frivolously, and consider that you might like an electric car just because ... it's a nicer vehicle.

Michael Thwaite is an electric-vehicle advocate who lives in New Jersey and works in information technology. He also runs the Tesla Motors Club. When he was 12 years old, he hoped that when he grew up, we’d all be driving electric cars. More than 30 years later, they’re finally here.

[PHOTOS: 1977 Ford Pinto Cruising Wagon, Wikipedia user Vegavairbob]

Ten Reasons Why You’ll Really Enjoy Owning an Electric Car (Page 3)

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