Futuristische ontwikkelingen

Deze afdeling is voor algemene topics die niet passen in wat reeds voorzien is. Ze moeten wel aansluiten bij ons thema.
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Pilgrim
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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Vr Jun 22, 2018 8:05 pm

De laatste resten van de Britse glorie... :wink2:

Skylon: A Story of Great Britain
NeoScribe - Gepubliceerd op 17 mrt. 2018



Reaction Engines – Making the leap to hypersonic travel
Reaction Engines Ltd - Gepubliceerd op 10 okt. 2017

De Islam is een groot gevaar!
Jezus leeft maar Mohammed is dood (en in de hel)

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xplosive
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Zo Jun 24, 2018 5:46 am

Ik vrees dat er veel eerder mensen op Mars geraken dan dat het eerste Skylon ruimtevliegtuig ooit gereed komt.
Gun jezelf wat je een ander toewenst     islam = racisme   & de hel op aarde voor mens en dier
                                   koran = racistisch & handboek voor criminelen
      Moslimlanden bewijzen dagelijks:    meer islam = meer verkrachte mensenrechten

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Hans v d Mortel sr
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Re: Futuristische ontwikkelingen

Berichtdoor Hans v d Mortel sr » Zo Jun 24, 2018 7:11 am

xplosive schreef:Ik vrees dat er veel eerder mensen op Mars geraken dan dat het eerste Skylon ruimtevliegtuig ooit gereed komt.

De gigantische de pot uitrijzende kosten voor de 'verplichte' nazorg van het koloniale tijdperk hebben Small Great Britain de das omgedaan. [icon_lol.gif]

Zorgplicht voor de eigen bevolking? Vergeet het maar! De allahtone bevolking in de koloniën heeft zelfbestuur uit alle macht afgedwongen om niet langer afhankelijk van Great Britain te zijn.

POLITIEK IS SMERIG.
Ik weet niks met zekerheid. Ik ben gelovig atheïst en verkondig uitsluitend eigen dogma's wegens gebrek aan de vrije wil.

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xplosive
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Za Jun 30, 2018 7:26 pm

 

6th June 2018 12:19 pm

Privately funded UK venture Tokamak Energy has hit plasma temperatures hotter than the sun’s core for the first time, reaching 15 million degrees Celsius.

The milestone was achieved using the ST40 device, the latest in a line of tokamaks the company has built in pursuit of commercial fusion. Using a technique known as merging compression, the ST40 releases energy as rings of plasma that crash together and magnetic fields in the plasma reconfigure – a process known as magnetic reconnection. Merging compression involves high electric currents running through the internal coils of the ST40, requiring power supplies to deliver thousands of amps in seconds. According to Tokamak Energy, it combines intricate electrical engineering processes that also place high demands on the mechanical engineering of the whole system.

“We are taking significant steps towards achieving fusion energy, doing so with the agility of a private venture, driven by the goal of achieving something that will have huge benefits worldwide,” said CEO Jonathan Carling.

“Reaching 15 million degrees is yet another indicator of the progress at Tokamak Energy and a further validation of our approach. Our aim is to make fusion energy a commercial reality by 2030. We view the journey as a series of engineering challenges, raising additional investment on reaching each new milestone.”



Though 15 million degrees may be an important landmark on the journey, it is a long way from the 100 million degrees required for thermonuclear fusion on Earth. The ST40 is the third machine in a five-stage plan that Tokamak Energy believes will lead to commercial fusion energy by the end of the next decade. Though it won’t be capable of energy gain – the holy grail of fusion – the ST40 is designed to reach the magic 100 million degree mark. Tokamak Energy will now be working towards that goal in a new facility with upgraded equipment.

“The world needs abundant, controllable, clean energy,” said Dr David Kingham, co-founder of Tokamak Energy. “Our business plan is built on strong scientific foundations and this major milestone provides further validation of our compact spherical tokamak route to fusion power.

“Fusion is a major challenge, but one that must be tackled. We believe that with collaboration, dedication and investment, fusion will be the best means of achieving deep decarbonisation of the global energy supply in the 2030s and beyond.”
Gun jezelf wat je een ander toewenst     islam = racisme   & de hel op aarde voor mens en dier
                                   koran = racistisch & handboek voor criminelen
      Moslimlanden bewijzen dagelijks:    meer islam = meer verkrachte mensenrechten

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Pilgrim
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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Ma Jul 02, 2018 2:33 am

Scientists can 3D print human heart tissue now. The future is here

Luke Dormehl - Posted on 6.29.18

Afbeelding

Long term, the goal of 3D bioprinting is to be able to 3D print fully functioning organs which can be used to replace the failing biological organs of humans in need of a transplant. That may still be years off, but Chicago-based biotech startup Biolife4D this week announced a major new milestone: Its ability to bioprint human cardiac tissue.

The scientific landmark followed shortly after the company opened a new research facility in Houston. It involved the printing of a human cardiac patch, containing multiple cell types which make up the human heart. It could one day be used to help treat patients who have suffered acute heart failure in order to restore lost myocardial contractility, the ability of the heart to generate force for pumping blood around the body.

“The cardiac patch that we printed demonstrated two major advancements,” Steven Morris, CEO of Biolife4D, told Digital Trends. “First, it demonstrated Biolife4D’s ability to take a patient’s own blood cells, reprogram them back into stem cells, reprogram them again to make the different type of cells which we need to 3D bioengineer our human heart viable for transplant, and then successfully 3D bioprint with those cells to make living human heart tissue. Second, this is the first time that a cardiac patch was 3D bioprinted that contains multiple cell types of which the human heart is made, and includes preliminary vascularization — all of which are needed to make a functional patch and to keep it alive after the bioprinting process.”

Given the potential life-saving ability of this technology, Biolife4D is far from alone in working toward this bioprinting goal. However, Morris noted that, while other companies have previously made similar patches, none have included each of the cell types which make up the heart, along with the vascularization needed to allow the body to nourish the cells and remove their waste products. “You can think of it like this is the first time all of the proper ingredients were used to properly make the recipe,” he continued.

Going forward, Biolife4D hopes to continue developing the patch in order to start preclinical testing in around six months. They will also continue with the broader project of printing a functioning human-scale heart by focusing on 3D bioprinting other components, such as valves, blood vessels, and a working mini-heart.

https://www.digitaltrends.com/cool-tech ... rt-tissue/
De Islam is een groot gevaar!
Jezus leeft maar Mohammed is dood (en in de hel)

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Pilgrim
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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Vr Jul 06, 2018 1:52 am

Belgisch ministerie keurt verbod op 'killer robots' goed

Gepubliceerd: 04 juli 2018

Volledig automatische wapens mogen in de toekomst niet in België gebruikt worden. Wel mag er in het land nog onderzoek naar dat soort 'killer robots' worden gedaan.

Daarvoor is een resolutie aangenomen in de Belgische Kamercommissie Landsverdediging, schrijft de VRT woensdag. De resolutie moet nog door het parlement goedgekeurd worden, al is volgens Kamerlid Hendrik Bogaert (CD&V) de politieke beslissing al genomen.

België heeft daarmee een preventief verbod goedgekeurd, waardoor het leger van het land nooit volledig automatische wapens mag gebruiken. Wapenproducenten kunnen zulke wapens ook in de toekomst niet in België produceren. Daarmee is België volgens de VRT het eerste land ter wereld dat zo'n verbod heeft goedgekeurd.

Het verbod regelt dat wapens niet zelfstandig kunnen beslissen om een aanval uit te voeren. Drones bestaan al langer en kunnen autonoom vliegen, maar openen het vuur alleen na een menselijke opdracht.

Een jaar geleden waarschuwden experts in een open brief over de gevaren van 'killer robots'. Onder anderen Tesla-topman Elon Musk hebben de brief ondertekend. In de tekst stond dat autonome robots een gevaar vormen voor burgers in oorlogsgebieden.

Door: NU.nl

https://www.nu.nl/gadgets/5346902/belgi ... -goed.html
De Islam is een groot gevaar!
Jezus leeft maar Mohammed is dood (en in de hel)

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Ali Yas
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Re: Futuristische ontwikkelingen

Berichtdoor Ali Yas » Vr Jul 06, 2018 6:39 am

Fijn voor de vijand.
Truth sounds like hate to those who hate truth.

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xplosive
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Za Jul 07, 2018 12:00 am

 

Sputnik, 13:21 03.07.2018 (updated 13:32 03.07.2018)

The unique optical computer is believed to have immense advantages over traditional computers, opening up new doors as far as raw computational power and energy use are concerned.

The supercomputer was developed by the All-Russian Scientific Research Institute of Experimental Physics in Sarov, about 375 km southeast of Moscow and is based on optical or photonic computing technology. The institute has already patented its project.

In optical computing, processing is carried out through the interaction of laser pulses, rather than electrical signals, as in conventional computing.

The optical computer is divided into electric and photonic sections, with machine code translated into laser pulses. Photons then pass into a photonic processor, where laser pulses interact, allowing for logic operations like the ones in traditional computers to be carried out. After that, laser beams leave the processor and return to the computer's electric portion, where optical information is converted back into electric-based information, becoming accessible to the user.

The Institute of Experimental Physics's chief research scientist, Sergei Stepanenko, the project's creator, told Sputnik that optical computers can solve mathematical problems that are beyond the scope of traditional semiconductor-based ones.
He pointed out, for example, that photonic technology allows for a reduction by tens or even hundreds of thousands of times in the amount of energy necessary to achieve the same performance as a conventional electrical computer.

"Where a supercomputer will require a building the size of a football field, an optical computer can achieve the same performance in a space the size of a half-liter coffee mug and have a heat output of about 100 watts – less than an electric kettle," Stepanenko explained.

Computer scientists around the world have been working on the concept of photonic computers for many years, but have been unable to come up with tangible results for a variety of reasons, including the nonlinear process in which multiple signals have to interact, the weakness of light waves compared to electromagnetic ones, and other technical issues.

However, the Experimental Physics Institute's workaround proposes a new scheme for the optical computer's work, with transitions between the optical and electrical-based components of the computer being performed as rarely as possible so as not to waste time and energy.

The theoretical maximum computational capacity of the photonic computer created by the Institute of Experimental Physics can be up to 50 petaflops (i.e., 50 quadrillion floating operations per second), with this peak power requiring just 100 watts of electricity. For comparison, 100 watts in a traditional computer would allow an output of about 5 teraflops, i.e., 10,000 times less. Furthermore, scientists believe that the power of their optical machine can be even further increased through reductions in the length of the light wave.

Practical applications for optical computers can include everything from mathematical problems to the study of genetic code. Given their comparably low use of power, it wouldn't be unreasonable to assume that they could be used in environments with limited access to electricity, in remote areas or in space.
Gun jezelf wat je een ander toewenst     islam = racisme   & de hel op aarde voor mens en dier
                                   koran = racistisch & handboek voor criminelen
      Moslimlanden bewijzen dagelijks:    meer islam = meer verkrachte mensenrechten

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Hans v d Mortel sr
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Re: Futuristische ontwikkelingen

Berichtdoor Hans v d Mortel sr » Za Jul 07, 2018 12:21 pm

Versta straks alle talen!

Afbeelding

Die ontevreden ober die iets onaardigs zegt, de mooie dame aan de bar die te koop is, of een Arabier die de wartaal van Allah spreekt. Er is altijd wel een moment dat je zou willen dat je de lokale taal verstond. En met Google Pixel Buds, een uiteraard niet-moslim-uitvinding, kan dat. Nou ja bijna.

Google Pixel Buds lijken op de oordopjes van je smartphone maar hebben een functie waarin Google Translate is geïntegreerd. Door Natural Language Processing kunnen ze verstaan wat er wordt gezegd, herkennen in welke taal dit is, en dit vertalen naar de taal van de ontvanger. En dat allemaal in een paar seconden. Zo kun je in principe alles verstaan wat er tegen je wordt gezegd, waar je ook bent. Jammer genoeg zijn de Pixel Buds alleen te verkrijgen in de VS, Engeland, Australië en Duitsland. Ook de techniek is nog niet feilloos. Maar het zal niet heel lang zal duren voordat we alle talen kunnen verstaan dankzij mobiele technologie. Dan kunnen we eindelijk de heilige taal van Allah begrijpen. Niet dankzij moslims, maar ondanks moslims. Dat die taal Arabisch is, de 'superieure' taal van de mislukte mensensoort ‘moslims’, spreekt vanzelf.
Ik weet niks met zekerheid. Ik ben gelovig atheïst en verkondig uitsluitend eigen dogma's wegens gebrek aan de vrije wil.

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xplosive
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Za Jul 07, 2018 2:15 pm

 
       The Dipole Drive: A New Concept for Space Propulsion

by Paul Gilster on June 29, 2018

One reason we look so often at sail technologies in these pages is that they offer us ways of leaving the propellant behind. But even as we enter the early days of solar sail experimentation in space, we look toward ways of improving them by somehow getting around their need for solar photons. Robert Zubrin’s work with Dana Andrews has helped us see how so-called magnetic sails (magsails) could be used to decelerate a craft as it moved into a destination system. Now Zubrin looks at moving beyond both this and solar wind-deflecting electric sails toward an ingenious propellantless solution. Zubrin presented the work at last April’s Breakthrough Discuss meeting, and today he fills us in on its principles and advantages. Read on for a look at a form of enhanced electric sail the author has christened the Dipole Drive.

by Robert Zubrin

Afbeelding

Abstract
The dipole drive is a new propulsion system which uses ambient space plasma as propellant, thereby avoiding the need to carry any of its own. The dipole drive remedies two shortcomings of the classic electric sail in that it can generate thrust within planetary magnetospheres and it can generate thrust in any direction in interplanetary space. In contrast to the single positively charged screen employed by the electric sail, the dipole drive is constructed from two parallel screens, one charged positive, the other negative, creating an electric field between them with no significant field outside. Ambient solar wind protons entering the dipole drive field from the negative screen side are reflected out, with the angle of incidence equaling the angle of reflection, thereby providing lift if the screen is placed at an angle to the plasma wind. If the screen is perpendicular to the solar wind, only drag is generated but the amount is double that of electric sail of the same area. To accelerate within a magnetosphere, the positive screen is positioned forward in the direction of orbital motion. Ions entering are then propelled from the positive to the negative screen and then out beyond, while electrons are reflected. There are thus two exhausts, but because the protons are much more massive than the electrons, the thrust of the ion current is more than 42 times greater than the opposing electron thrust, providing net thrust. To deorbit, the negative screen is positioned forward, turning the screen into an ion reflector. The dipole drive can achieve more than 6 mN/kWe in interplanetary space and better than 20 mN/kWe in Earth, Venus, Mars, or Jupiter orbit. In contrast to the electric sail, the ultimate velocity of the dipole drive is not limited by the speed of the solar wind. It therefore offers potential as a means of achieving ultra-high velocities necessary for interstellar flight.

Spoiler! :
Background
The performance of rockets as propulsion systems is greatly limited by their need to carry onboard propellant, which adds to the mass which must be propelled exponentially as the extent of propulsive maneuvers is increased. For this reason, engineers have long been interested in propulsion systems that require no propellant.

The best known propellantless system is the solar sail, which derives its thrust by reflecting light emitted by the Sun. Solar sails are limited in their performance however, by their dependence upon sunlight, which decreases in strength with the square of the distance, and the laws of reflection, which dictate that the direction of thrust can only lie within 90 degrees of the vector of sunlight. Moreover, because photons move so swiftly, the amount of thrust that can be derived by reflecting light is at best 0.0067 mN/kW (at 100% reflectance, full normal incidence), which means that very large sails, which necessarily must have significant mass and be difficult to deploy, must be used to generate appreciable thrust. As a result, while solar sails have been studied since the time of Tsiolokovsky [1], we are only now beginning to experiment with them in space.

An alternative to the solar sail is the magnetic sail, or magsail, which was first proposed by Zubrin and Andrews in 1988, and subsequently analyzed extensively by them in a variety of further papers [2,3] in the 1990s. The magnetic sail uses a loop of superconducting wire to generate a magnetosphere to deflect the solar wind. Assuming the development of high temperature superconducting wire with the same current density as existing low temperature superconductors, a magsail should be able to generate significantly higher thrust to weight than is possible with solar sails. However such wire has yet to be developed.

Another propellantless propulsion system of interest is the electric sail [4], which like the magsail operates by deflecting the solar wind, in its case by using an electrostatic charge. As a result, like the magsail, the classic electric sail (electric sail) cannot operate inside of a planetary magnetosphere other than as a drag device, has its thrust decrease with distance from the Sun, and is limited in the potential direction of its thrust. Because of the low momentum density of the solar wind, electric sails must be even bigger than solar sails. However, because only sparsely spaced thin wires are needed to create sail area, higher thrust to mass ratios can be achieved than are possible using solar sails which require solid sheets of aluminized plastic.

Electrodynamic tethers [5] have also been proposed, which use the interaction of a current in a tether with the Earth’s geomagnetic field to produce thrust. In addition to facing a variety of engineering and operational issues, however, such systems can only operate in a planetary magnetic field and can only thrust in a direction normal to the field lines, a consideration which limits their applicability.

Finally, we note recent claims for a system called the EM Drive [6], which according to its proponents can generate about 1 mN/kWe, in any direction, without the use of propellant, an external light source or plasma wind, or magnetic field. Such performance would be of considerable interest. However, as it appears to contradict the laws of physics, there is reason to suspect that the measurements supporting it may be erroneous.

As a result, there clearly remains a need for a new type of propellantless propulsion system, which can operate both inside and outside of a planetary magnetosphere, can thrust in a multitude of directions, and which is not dependent upon sunlight or the solar wind as a momentum source. The dipole drive is such a system.

The Dipole Drive
The principle of operation of the dipole drive while accelerating a spacecraft within a planetary magnetosphere is illustrated in Fig. 1 below.

Afbeelding
Fig. 1. The Dipole Drive Accelerating within a Magnetosphere.

In Fig. 1 we see two parallel screens, with the one on the left charged positive and the one on the right charged negative. There is thus an electric field between them, and effectively no field outside of them, as on the outside the field of each screen negates the other. There is also a voltage drop between the two, which for purposes of this example we will take to be 64 volts.

Protons entering the field region from the left are accelerated towards the right and then outward through the right-hand screen, after which they escape the field and experience no further force. Protons entering from the right are reflected towards the right, adding their momentum to that generated by the protons accelerated from left to right. There is thus a net proton current from left to right, and a net proton thrust towards the left.

In the case of electrons, the situation is exactly the opposite, with a net electron current from right to left, and a net electron thrust towards the right. Note that while electrons entering from the right will be greatly accelerated by the field, reflected electrons will only be reflected with their initial velocity. There will also be an electron current through the outside plasma to neutralize the net proton flow to the right.

Because space plasmas are electrically neutral, the number density of both electrons and ions (which for the moment we will consider to be protons, but may which – advantageously – be heavier species, as we shall discuss later) will be the same, so the proton and electron electrical currents will be equal, as will the power associated with each of them. However because the mass of a proton is about 1842 times as great as the mass of an electron, the thrust of the proton current will be about 43 times greater than the opposing electron current thrust (because the momentum of particles of equal energy will scale as the square root of their mass, sqrt(1842)=43) and the system will generate a net thrust. The acceleration of the electrons is a form of drag, which is provided for by loss of spacecraft kinetic energy. It therefore could, in principle be used to generate electric power, partially compensating for the power consumed to accelerate the protons. In the following examples, however, we will assume that there is no provision for doing this, i.e. that the efficiency of any such energy recovery is zero.

To see what the performance of a dipole drive might be, let us work an example, assuming a 500 W power source to drive the system. The electron current negates about 2% of the thrust (1/43rd) produced by the proton current. The maximum possible jet power is thus about 490 Wj. Assuming additional inefficiencies, we will round this down to 400 Wj, for a total system electrical to jet power efficiency of 0.8.

A Coulomb of protons has a mass of 0.011 milligrams. If the jet power is 400 W, and the potential difference is 64 V, so the proton current will be 6.25 A, and have a mass flow of 0.0652 mg/s.

The relationship of jet power (P) to mass flow (m) and exhaust velocity (c) is given by:

P = mc2/2 (1)

Taking P = 400 W and m = 0.0652 mg/s, we find that c= 110,780 m/s. Since thrust (T) is given by T=mc, we find:

T = mc = 7.2 mN (2)

This is a rather striking result. It will be recalled that the electrical power driving this system is 500 W. So what we are seeing here is thrust to power ratio of 14.4 mN/kWe, more than ten times better than that claimed for the EM Drive, but done entirely within the known laws of physics!

If it is desired to deorbit (decelerate) a spacecraft, the direction of the screens would be reversed, with the negative screen leading in the direction of orbital motion. In this case, the screens would become a proton reflector. An electric sail could also be used as a drag device to serve the same purpose. However, because the dipole drive doesn’t merely create drag against passing protons, but reflects them, it would create twice the drag of an electric sail of the same area. If the dipole drive is positioned obliquely to the wind angle, it can reflect protons, with the angle of incidence equaling the angle of reflection. For example, if it is tilted 45 degrees to the wind, a force will be generated perpendicular to the wind, that is “lift” will be created. Such maneuvers could also be done with the dipole drive in acceleration mode, deflecting protons to combine lift with thrust. Using this capability, a dipole drive propelled spacecraft in orbit around a planet could execute inclination changes.

To summarize, in contrast to the electric sail which can only create drag against the wind to lower its orbit, the dipole drive can thrust in any direction, raising or lowering its orbit or changing its orbital inclination. In addition, when used as a drag device, the dipole drive can create twice the drag per unit area as the electric sail.

The Dipole Drive in Planetary Orbit
Let us therefore analyze the system further. The dipole drive exerts no field outside of its screens, so the only plasma it collects is the result of its own motion through the surrounding medium. So how big does its screen need to be?

We consider first the case of the above described dipole drive system operating in LEO at an altitude of 400 km, being used to thrust in the direction of orbital motion. It is moving forward at an orbital velocity of 7760 m/s. The average density of ions at this altitude is about 1,000,000 per cc. Assuming (conservatively) that all the ions are protons, the required ion mass flow of 0.0652 mg/s would be swept up by a screen with a radius of 127 m.

It may be noted however, that at 400 km altitude there are also O+ ions, each with a mass 16 times that of a proton, with a numerical density of about 100,000/cc. These therefore more than double the ion mass density provided by the protons alone. If these are taken into account, the required scoop radius would drop to about 80 m.

Another way to reduce the scoop size would be by going to higher voltage, so that more power can be delivered to a smaller number of ions. If, for example, we quadrupled the voltage to 256 volts, the exhaust velocity would double, to 222 km/s, allowing us to cut the mass flow by a factor of four, and the scoop radius by a factor of two, to just 40 m. The thrust, however, would be cut in half, giving us 3.6 mN/kWe.

As we go up in altitude, the plasma density decreases, as does the orbital velocity, requiring us to go to larger scoops. Examples of 500 W dipole drive systems operating at a variety of altitudes are provided in Table 1. In Table 1, Vo and C are orbital velocity and exhaust velocity, in km/s.

Table 1. Dipole Drive Systems Operating in Earth Orbit (Power=500 W)

Afbeelding

It can be seen that the dipole drive is a very attractive system for maneuvering around from LEO to MEO orbits, as the high ion density makes the required scoop size quite modest. It should be emphasized that the above numbers are for a 500 W system. If a 5 W dipole drive thruster were employed by a microsatellite, the required scoop areas would be reduced by a factor of 100, and the radius by a factor of 10.

It may be noted that Mars, Venus and Jupiter all have ion densities in low orbit comparable to those above. For example, Mars has 500,000/cc at 300 km, Venus has 300,000/cc at 150 km, and Jupiter has 100,000/cc at 200 km, making the dipole drive attractive for use around such planets as well. Many of the moons of the outer planets also have ionospheres, and the dipole drive should work very well in such environments.

As one ascends to higher orbits, the density of ions decreases dramatically, while the orbital speed decreases as well. For example, in GEO, the ion density is only about 20/cc, while the orbital velocity is 3 km/s. These two factors combine to make much larger scoops necessary. So, for example, in GEO, a 500 W dipole drive operating at 1024 volts would need a scoop 3.6 km in radius.

Because the effectiveness of the dipole drive decreases at higher altitudes while operating within the magnetosphere, the best way for a dipole drive propelled spacecraft to escape the Earth is not to continually thrust, as this would cause it to spiral out to trans GEO regions where it would become ineffective. Rather, what should be done is to only employ it on thrust arcs of perhaps 30 degrees around its perigee, delivering a series of perigee kicks that would raise its apogee on the other side of its orbit higher and higher until it escaped the magnetosphere and became able to access the solar wind.

The Dipole Drive in Interplanetary Space
The dipole drive can also operate in interplanetary space. Compared to planetary orbit, the ion densities are lower, but this is partially compensated for by much higher spacecraft velocities relative to the plasma wind. As a result, the required scoop sizes are increased compared to planetary orbital applications, but not by as much as considerations of ion density alone might imply.

Let us consider the case of a dipole drive traveling in heliocentric space at 1 AU, positioned at an angle of 45 degrees to the wind, with its negative screen on the sunward side. It would thus reflect solar wind protons 90 degrees, thereby accelerating itself forward in the direction of orbital motion. A diagram showing the dipole drive operating as a sail in interplanetary space is shown in Fig. 2.

Afbeelding
Fig. 2 The Dipole Drive Operating as a Sail in Interplanetary Space.

The solar wind has a velocity of 500 km/s, so to insure reflection, we employ a voltage of 2028 volts, sufficient to reverse the motion of a proton moving as fast as 630 km/s. With a density of 6 million protons per cubic meter, the wind has a dynamic pressure of 1.25 nN/m2. As the sail is positioned 45 degrees obliquely to the wind, its effective area will be reduced by a factor of 0.707, with the thrust reduced to 0.9 nN/m2. In this case, virtually all of the protons hitting the sail will be coming from the sunward side, and since they are reflected without adding any kinetic energy, no power is required to drive them. However, we still have an electron current coming from the sunward side being accelerated outward. This requires power. With 500 W, total radial thrust would be 1.27 mN, with 1.27 mN also delivered in the direction of orbital motion, for a L/D ratio of 1. The total effective screen area would therefore need to be 1,414,000 m2, with an actual area of 2,000,000 m2, requiring a radius of 798 m. Total thrust to power would be 3.6 mN/kWe.

If instead we had not concerned ourselves with obtaining complete deflection of each particle, we could have used a lower voltage. This would increase the thrust per unit power, but increase the required sail area for a given amount of thrust. So, for example, if we chose 512 volts, we would have a total thrust of 3.6 mN, for a thrust/power ratio of 7.2mN/kWe, but need a sail radius of 1127 m.

It may be noted that all of these results are for a 500 W dipole drive. A microsatellite might employ a 5 W dipole drive, in which case the required scoop radii would drop by a factor of 10.

The thrust and diameter of a 1 kWe dipole drive system operating as a solar wind sail in interplanetary space at 1 AU is shown in fig. 3.

Afbeelding
Fig. 3. Thrust and Diameter of a 1 kWe dipole drive system operating as a solar wind sail in interplanetary space.

Use of the Dipole Drive for Interstellar Flight
In contrast to the electric sail, the dipole drive can be used to accelerate a spacecraft at velocities greater than that of the solar wind. For example, consider a spacecraft moving away from the Sun at a velocity of 1000 km/s. The solar wind is following it at a velocity of 500 km/s, so relative to the spacecraft there is a wind moving inward towards the sun at a velocity of 500 km/s. In this case, to accelerate the spacecraft would direct its positive screen away from the sun. This would cause it to accelerate protons sunward, while reflecting electrons outward, for a net outward thrust. At 500 km/s the protons are approaching the spacecraft with a kinetic energy equal to 1300 volts. It can be shown that employing a screen voltage difference that is about triple the kinetic voltage produces an optimal design for an accelerating system, while one using a voltage difference equal to the kinetic voltage is optimal for deceleration. This is illustrated in figs 4 and 5 which respectively show the kinetic voltage as a function of velocity, and the relative power/ thrust and area/thrust ratios of the spacecraft as a function of the dimensionless parameter Z, where Z=(engine voltage)/(kinetic voltage.)

Afbeelding
Fig 4. Kinetic Voltage as a function of spacecraft velocity.

Afbeelding
Fig 5. Relative Power/Thrust and Area/Thrust as a function of Z=(engine voltage)/(kinetic voltage.) There is a step factor of 2 increase in thrust during deceleration when Z reaches 1, because protons are reflected. For acceleration, Power/Thrust ~ 1 + sqrt(1+Z), while Area/Thrust ~ 1/(-1 + sqrt(1+Z)).

If we add 3900 volts to the incoming protons, quadrupling their energy, we will double their velocity relative to the spacecraft, thereby providing an effective exhaust velocity of 500 km/s. The solar wind has a density of 6 million protons/m3 at 1 AU, with ambient density decreasing to 1 million/m3 in interstellar space. If we take the former value, we get a thrust of (1.67e-27 kg/proton)(500,000m/s)2(6,000,000/m3) = 2.5 nN/m2. If we take the latter value, it would be 0.42 nN/m2. The proton current at the smaller value would be 80 nA/m2, which at 3900 volts works out to 0.312 mW/m2. The thrust to power ratio would therefore be 1.35 mN/kW. (This ratio would also hold true at the 1 AU value, but the magnitudes of both the thrust and power per unit area would be six times greater.)

If a dipole drive powered spacecraft were receding 500 km/s directly away from the Sun, it would see no relative wind and thus produce no thrust. However, like a modern sailboat that can sail faster crosswind than downwind, because it can generate lift, the dipole drive can get to speeds above 500 km/s by sailing across the wind. As the spacecraft’s crosswind speed increases, it becomes advisable to turn the sail to ever greater angles to the solar wind and increasingly normal to the crosswind. As this occurs, the L/D resulting from solar wind reflection increases while the total solar wind thrust decreases. At the same time, however, thrust resulting from the acceleration through the screens of crosswind protons increases, maintaining total thrust constant at ever higher L/D (relative to the solar wind) levels. Once the crosswind velocity exceeds the solar wind velocity the solar wind becomes increasingly irrelevant and the dipole drive becomes a pure acceleration system, driving the incoming crosswind plasma behind it to produce thrust,

As the speed of the spacecraft increases relative to the wind, it is necessary to increase the voltage in order maintain thrust/power ratio efficiency. For example, let’s say we want to achieve 3000 km/s, or 0.01c. Then the kinetic energy equivalent voltage of the approaching protons would be 47 kV. So, to double this velocity we need to quadruple the total voltage, or add a sail voltage drop of 141 kV. The proton current would have a value of 480 nA/m2, with a power of 68 mW/m2. The thrust would be 15.1 nN/m2, for a thrust to power ratio of 0.22 mN/kW.

It may be observed that since the necessary voltage increases as the square of the velocity, with power increasing with voltage but thrust increasing with velocity, the thrust to power ratio of the dipole drive decreases linearly with velocity. This puts limitations on the ultimate velocity achievable. For example, the most optimistic projections for advanced large space nuclear power systems project a mass to power ratio of 1 kg/kW. If we accept this number, then, neglecting the mass of any payload or the dipole drive system itself, then the system described in the previous paragraph performing with a thrust to power ratio of 0.22mN/kilowatt at 3000 km/s would have an acceleration of 0.00022m/s2, or 7 km/s per year. The average acceleration getting up to 3000 km/s would be twice this, so the spacecraft would take 214 years to reach this speed. During this time it would travel 1.07 light years. To reach 6000 km/s (0.02 c) starting from negligible velocity would require 857 years, during which time the spacecraft would travel 8.57 light years. The performance of such a system is shown in Table 2. Note 63,000 AU = 1 light year. The performance shown assumes an advanced 1 kg/kWe power supply. If a more near-term power system with a higher mass/power is assumed, the time to reach any given distance increases as the square root of the mass/power ratio. So for example, if we assume a conservative near-term space nuclear power reactor with a mass/power ratio of 25 kg/kW, the time required to reach any given distance would increase by a factor of 5.

Table 2. Advanced Dipole Drive Performance for Ultra High-Speed Missions (1 kg/kW power)

Afbeelding

It can be seen that advanced dipole drive spacecraft could be quite promising as a method of propulsion for missions to near interstellar space, for example voyages to the Sun’s gravitational focus at 550 AU. Unless much lighter power systems can be devised than currently anticipated however, they would still require centuries to reach the nearest stars. Power beaming may provide an answer. However such technologies are outside the scope of this paper.

If a spacecraft has been accelerated to interstellar class velocities, whether by means of the dipole drive or any alternative technology, the dipole drive provides a means of deceleration without power (it could actually generate power) by creating drag against the relative plasma wind. This feat can also be done by a magnetic sail or an electric sail. However because it can also create lift as well as drag, the dipole drive offers much greater maneuverability during deceleration as well as a means to freely maneuver within the destination solar system after arrival.

Dipole Drive Design Issues
Let us consider the case of a 2 kg microsatellite operating in LEO, with 5 W of available power to drive a dipole drive. (Note, a typical CubeSat has a mass of 1.3 kg. At 20 kg/kWe, a 5 W solar array should have a mass of about 0.1 kg.) If we operate it with a voltage of 16 Volts, it will produce 28.8 mN/kWe, or 0.144 mN thrust over all. It would have an acceleration of 0.000072 m/s2. This would allow it to generate a ΔV of 2288 m/s in a year, sufficient to provide extensive station keeping propulsion, substantially change its inclination, or to raise it from a 400 km altitude orbit to a 700 km orbit in 1.6 months. To generate this much thrust at 400 km would require a scoop with a radius of 16 m, while doing so at 700 km would require a scoop with a radius of 58 m. Let us assume that the scoop is made of aluminum wire mesh, using wires 0.1 mm in diameter separated by distances of 2 m. Each square meter of mesh would thus have about 1 m length of wire. This needs to be doubled as there are two meshes, one positive and one negative. Therefore, a scoop with a radius of 16 m would have a mass of 32 grams. If the propulsion system were used simply for station keeping, inclination change, or deorbit functions at the 400 km altitude, that’s all that would be needed. To operate at 700 km, a 116 gram scoop would be required. From these examples we can see that the use of the dipole drive to provide propulsion for microsatellites in LEO could potentially be quite attractive, as the modest scoop sizes required do not pose major deployment challenges.

Now let us consider a 100 kg interplanetary spacecraft in interplanetary space, operating with 500 W at a voltage of 2028 volts. From the discussion above it can be seen that this would generate about 2.54 mN of thrust in the direction of orbital motion. The scoop would need to have a radius of about 800 m. In interplanetary space, the Debye shielding length is ~60 m, and so a screen with a 20 m mesh would suffice. Such a screen would have a mass of about 8.5 kg, which would be well within the spacecraft mass budget. The 2.54 mN thrust would accelerate the spacecraft at 0.000025 m/s2. It could thus impart a V to the spacecraft of about 804 m/s per year. Higher accelerations could be provided by increasing the spacecraft power to mass ratio.

The deployment of large scoops composed of two parallel, oppositely charged meshes poses operational and design issues. Prominent among these is the fact that the two opposite charged screens will attract each other. However the total force involved is not that large. For example, let us consider a configuration consisting to two sails of 500 m radius separated by 500 m with a 2 kV potential difference. Then the electric field between them will be 4 volts/m. The area of each screen will be 785,400 m2. From basic electrostatics we have EA = Q/ε, so Q, the charge of each screen will be given by Q=(4)(785,400)(8.85 e-12) = 0.000028 coulombs. The electrostatic force on each sail is given by F=QE, so the total electrostatic force of each sail will be 0.1 mN. This is about a tenth the thrust force exerted by the screens themselves. Nevertheless, as small as they are, both of these forces will need to be negated. This can be done either with structural supports or by rotating the spacecraft and using artificial gravity to hold the sails out perpendicular to the axis of rotation. An alternative is to use the self-repulsion of the charge of each sail to help hold it out flat. In such a configuration two sails held separate from each other by a boom attached to their centers could be expected to curve towards each other at their edges until the stiffening self-repulsive force on each sail from its own charge balanced the bending forces exerted by the spacecraft’s acceleration, the push of the wind, and the attractive force of the opposite sail.

One way to avoid such issues would be to design the system as a literal dipole, with a rod holding a positive charge at its end to the front of the spacecraft, and a rod holding the negative charge pointing to the rear of the spacecraft. Seen from a distance, such a configuration is electrically neutral and would exert negligible field. However, in the zone between the charges, there is a strong field from one pole to the other. Particles entering this field along the rod center lines would experience the full voltage drop. Particles entering the field at some distance from this central axis would experience a lower voltage drop. The overall functional voltage of such a system, from the point of view of power consumption and exhaust velocity, would be an average over many particles entering the dipole field at all distances from its axis. This is obviously a more complex configuration to analyze than that of the two parallel screens discussed so far, but it may be much simpler to implement in practice on an actual spacecraft.

A critical issue is the material to be used to create the dipole drive. In his original paper on the classic electric sail [4], Pekka Janhunen suggested using copper wires with diameters between 2.5 and 10 microns. This is not an optimal choice, as copper has a much lower strength to mass ratio than aluminum, and such thin strands would be quite delicate. For this reason, in the above examples we specified aluminum wire with 100-micron diameters. A potentially much better option, however, might be to use aluminized Spectra, as spectra has about 10 times the yield strength of aluminum, and roughly 1/3 the density (Aluminum 40,000 psi, 2700 kg/m3, compared to Spectra 400,000 psi, 970 kg/m3.). Spectra strands with 100-micron diameters and a coating of 1 micron of aluminum could thus be a far superior material for dipole drive system, and classic electric sails as well. An issue however is Spectra’s low melting point of 147 C. Kevlar, however, with a yield strength of 200,000 psi, a density of 1230 kg/m3, and a melting point of 500 C could provide a good compromise. Still another promising option might be aluminized strands made of high strength carbon fiber, such as the T1000G (924,000 psi, 1800 kg/m3) produced by Toray Carbon Fibers America.

Some options for dipole drive spacecraft configurations are show in in Fig. 6. As can be seen, small dipole drive systems can be used for spacecraft control, for example as an empennage. Such small dipole drive units could also be used for attitude control on non-dipole drive spacecraft, such as solar sails.

Afbeelding
Fig. 6. Options for dipole drive spacecraft configuration. Small dipole drive systems can be used for attitude control.

As with the electric sail, the dipole drive must deal with the issue of sail charge neutralization caused by the attraction of ambient electrons to the sail’s positive screen. In reference 4, P. Janhunen showed that the total such current that an electric sail would need to dispose of would be modest, entailing small power requirements if ejected from the spacecraft by a high voltage electron gun. In the case of the dipole drive, the current would be still smaller because the spacecraft has no net charge. In addition electrons acquired by the positive screen could be disposed of by using the power source to transport them to the negative screen. Alternatively, if an electron gun were used, its required voltage would be less than that needed by an electric sail because external to the screens, the dipole drive’s field is much weaker and falls off much more quickly. For these reasons, the issue of sail charge neutralization on the dipole drive should be quite manageable.

Because the dipole drive does not interact with plasma outside of the zone between its screens, the issue of Debye shielding of its screen system to outside charges is not a concern. Debye shielding of its individual wires within screens can be dealt with by means of adequately tight wire spacing. As shown by Janhunen [4], such spacing may be quite liberal (~60 m in near Earth interplanetary space), enabling sails with very low mass to area ratios. [7]
Conclusion
The dipole drive is a promising new technological concept that offers unique advantages for space propulsion. Requiring no propellant, it can be used to thrust in any direction, and both accelerate and decelerate spacecraft operating within planetary magnetospheres, in interplanetary space, and interstellar space. Unlike magnetic sails and electric sails, it can generate both lift and drag, and its maximum velocity is not limited by the speed of the solar wind. Near-term dipole drives could be used to provide a reliable, low cost, low mass technology to enable propellantless movement of spacecraft from one orbit to another, to provide station keeping propulsion, or to deorbit satellites, as required. Then dipole drive could also be used as a method of capturing interplanetary spacecraft into orbit around destination planets, or of lowering the orbits of spacecraft captured into initial elliptical orbits using high thrust propulsion. The latter application is particularly interesting, because it could enable a small lightweight lunar ascent vehicle to carry astronauts home from the Moon by launching directly from the lunar surface to trans-Earth injection and then subsequently lower itself to LEO to rendezvous with a space station or reentry capsule spacecraft without further use of propellant. Such an approach could potentially reduce the mass of a manned lunar mission to within the launch capacity of a single Falcon Heavy. Because it needs no propellant, the dipole drive offers the unique advantage of being able to provide its propulsion service to any spacecraft indefinitely. While the dipole drive is most attractive in orbital space whether ambient plasma is thickest, it can be used in interplanetary space and even enable interstellar missions as well, becoming more attractive for such applications as ancillary technologies, such as power generation evolve.

There are many technical issues that need to be resolved before practical dipole drive spacecraft can become a reality. However both the theory of dipole drive operation and it potential benefits are clear. Work should therefore begin to advance it to flight status. The stars are worth the effort.

References
1. Jerome Wright (1992), Space Sailing, Gordon and Breach Science Publishers

2. D. G. Andrews and R. Zubrin, “Magnetic Sails and Interstellar Travel”, IAF-88-553, 1988

3. R. Zubrin and D.G Andrews, “Magnetic Sails and Interplanetary Travel,” AIAA-89-2441, AIAA/ASME Joint Propulsion Conference, Monterey, CA July 1989. Published in Journal of Spacecraft and Rockets, April 1991.

4. Pekka Janhunen, “Electric Sail for Spacecraft Propulsion,” J. Propulsion, Vol. 20, No. 4: Technical Notes, pp763-764. 2004.

5. Cosmo, M.L., and Lorenzini, E.C., Tethers in Space Handbook, NASA Marshall Space Flight Center, 1997

6. D. Hambling, “The Impossible EM Drive is Heading to Space,” Popular Mechanics, September 2, 2016.

7. “Debye Length,” Plasma Universe.com, https://www.plasma-universe.com/Debye_length accessed Feb 18, 2018.

Afbeelding
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Ma Jul 09, 2018 4:01 pm

 

Brian Wang | July 7, 2018

Afbeelding

Thomas Sterling has retracted his prediction that we will never reach zettaFLOP computers. He now predicts zettaFLOPS can be achieved in less than 10 years if innovations in non-von Neumann architecture can be scaled. With a change to cryogenic technologies, we can reach yottaFLOPS by 2030.

The world is currently on the verge of exaFLOP supercomputers. The USA just revealed a 200 petaFLOP supercomputer. China will soon complete three supercomputers that will be close to exaFLOP and one or more could reach exaFLOP performance.

Computer performance

Name          Unit          Value

kiloFLOP      kFLOP       10³
megaFLOP    MFLOP       10⁶
gigaFLOP     GFLOP       10⁹
teraFLOP     TFLOP       10¹²
petaFLOP     PFLOP       10¹⁵
exaFLOP      EFLOP       10¹⁸
zettaFLOP    ZFLOP       10²¹
yottaFLOP    YFLOP       10²⁴
brontoFLOP  BFLOP       10²⁷
geoFLOP      GeFLOP     10³⁰

Many see quantum computing, neuromorphic computing, and optical computing as technologies which could disrupt high-performance computing.

Niobium Josephson Junction-based technologies cooled to four Kelvins can operate beyond 100 and 200 GHz and has slowly evolved over two or more decades. Quantum annealing is performed at 40 milli-Kelvins or lower. The four Kelvin requirement is easy in comparison. However, latencies measured in cycles grow proportionally with clock rate and superconducting supercomputing must take a very distinct form from typical von Neumann cores. Sterling is not putting forward a controversial position.

Possible alternative non-von Neumann architectures could address the latency challenge. Cellular automata and data flow could be used, but problems will need to be overcome. The post-exascale era has a lot of possibilities.

There was a Cordis research project on non-von Neumann architectures. Reconfigurable non-von-Neumann Accelerators.

In 2016, a new Molecular mechanical nanocomputer design could be 100 billion to 100 trillion times more energy efficient than todays supercomputers.

At the same ten megawatt power level as some supercomputers, molecular nanocomputer supercomputers could achieve yottaFlop, brontoFlops or even geoFlop compute levels.

Ralph Merkle, Robert Freitas and others have a theoretical design for a molecular mechanical computer that would be 100 billion times more energy efficient than the most energy efficient conventional green supercomputer. Removing the need for gears, clutches, switches, springs makes the design easier to build.

Existing designs for mechanical computing can be vastly improved upon in terms of the number of parts required to implement a complete computational system. Only two types of parts are required: Links, and rotary joints. Links are simply stiff, beam-like structures. Rotary joints are joints that allow rotational movement in a single plane.

So a technological brute force acceleration looks likely in the 15 to 35 year timeframe. We will at least have some improvements on deep learning and reinforcement learning. Substantial trillion+ qubit general purpose quantum computers and all optical computers will also likely be available.

Men schat dat het menselijk brein met ongeveer 1 exaFLOP rekenkracht van een computer benaderd kan worden, zie hier. Een supercomputer met die capaciteit zou in 2020 gereed kunnen zijn volgens China’s exascale supercomputer operational by 2020.

Per 5 jaar zou dat dan een factor 1000 sneller worden.

Dit is een verdubbeling per 6 maanden, waarmee de oorspronkelijke wet van Moore zelfs overtroffen wordt :

Toen Moore de voorspelling in 1965 deed ging hij nog uit van een verdubbeling per 12 maanden. In 1975 stelde hij de voorspelling bij en zei ervan uit te gaan dat het groeitempo zou vertragen tot een verdubbeling per 24 maanden.

Dus een zettaFLOP supercomputer in 2025 en een yottaFLOP supercomputer in 2030. Waartoe zal een supercomputer in 2030 met 1 miljoen keer de capaciteit van 1 menselijk brein in staat zijn?
Gun jezelf wat je een ander toewenst     islam = racisme   & de hel op aarde voor mens en dier
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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Za Jul 14, 2018 1:26 am

Amazon-baas gaat ruimtevluchten verkopen vanaf 200.000 dollar

Gepubliceerd: 13 juli 2018

Afbeelding
Foto: Blue Origin

Het ruimtebedrijf van Amazon-CEO Jeff Bezos gaat ruimtevluchten verkopen voor minstens 200.000 dollar, omgerekend ongeveer 170.000 euro.

Dat vertellen bronnen die bij raketbouwer Blue Origin werken aan Reuters. Kaartjes voor de ruimtevluchten zullen worden verkocht voor tussen de 200.000 en 300.000 dollar.

Blue Origin werkt op het moment aan een herbruikbare raket. Omdat de raket opnieuw gebruikt kan worden, moeten de kosten van een ruimtevlucht significant verlaagd worden.

De passagiersvluchten worden uitgevoerd door de New Shepard-raket. Deze moet autonoom kunnen rondvliegen en heeft plek voor zes passagiers. De raket zal op 100 kilometer hoogte boven de aarde vliegen, waar de inzittenden ook kunnen voelen hoe het is om geen zwaartekracht te hebben.

Passagierscapsule
Inmiddels heeft Blue Origin acht testvluchten met de raket uitgevoerd. Bij geen van deze tests zaten er passagiers aan boord. Volgens de bronnen zal de passagierscapsule in de komende weken getest worden.

Bezos wil op termijn naar Mars met het ruimtebedrijf. Voor die tijd is hij van plan om de maan te bezoeken met zijn raketten.

Door: NU.nl

https://www.nu.nl/gadgets/5362151/amazo ... ollar.html
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Re: Futuristische ontwikkelingen

Berichtdoor Ali Yas » Za Jul 14, 2018 10:17 am

Een herbruikbare raket betekent meer brandstof per lading.
Truth sounds like hate to those who hate truth.

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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Za Jul 14, 2018 4:09 pm

Ali Yas schreef:Een herbruikbare raket betekent meer brandstof per lading.

En aanzienlijk minder brandstof/energie voor de productie.
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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Di Jul 17, 2018 2:39 am

US video - SABRE
Reaction Engines Ltd - Geüpload op 25 jun. 2018

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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Di Jul 17, 2018 10:56 pm

Volledig zelfrijdende auto pas in 2065 in meerderheid op de weg

Gepubliceerd: 17 juli 2018

Afbeelding
Foto: General Motors

Een volledig zelfrijdende auto kan nog tientallen jaren op zich laten wachten. Mogelijk rijden er pas rond 2065 meer zelfrijdende auto's dan gewone voertuigen op de Nederlandse weg.

Dat blijkt uit bestudering van verschillende onderzoeken door de Stichting Wetenschappelijk Onderzoek Verkeersveiligheid (SWOV) en brancheorganisatie RAI Vereniging.

Vooral de stap naar volledig autonoom rijden vergt veel ontwikkeltijd vanwege de complexiteit en onvoorspelbaarheid van menselijk gedrag waar auto's mee om moeten kunnen gaan.

De onderzoekers verwachten dat de introductie van zelfrijdende auto's in fasen zal plaatsvinden. De derde fase zou het meest complex zijn. Hierbij rijden mensen in deels zelfstandige voertuigen, maar moeten ze zelf ook op de weg letten en ingrijpen bij noodsituaties.

Zo'n deels autonoom voertuig zou andere rijvaardigheden vereisen van bestuurders dan nu het geval is. Omdat mensen die vaardigheden nog niet hebben, kunnen er gevaarlijke situaties ontstaan. Recent veroorzaakte de bestuurder van een deels zelfrijdende Uber nog een dodelijk ongeluk, omdat niet op de weg werd gelet.

2065 of 2085
De onderzoekers verwachten dat de volledig zelfrijdende auto op zijn vroegst in 2065 in de meerderheid is. In het slechtste geval kan het nog enkele decennia langer duren en komen volledig zelfrijdende auto's pas in 2085 op de markt.

Volgens RAI Vereniging kan de zelfrijdende auto wel helpen om het aantal verkeersslachtoffers terug te dringen, omdat ze ongelukken kunnen voorkomen.

Door: ANP/NU.nl

https://www.nu.nl/gadgets/5368376/volle ... d-weg.html
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Za Jul 21, 2018 12:31 pm

 

Max Planck Institute of Neurobiology, Dr. Stefanie Merker, Public Relations, July 16, 2018

The function of the brain is based on the connections between nerve cells. In order to map these connections and to create the connectome, the “wiring diagram” of a brain, neurobiologists capture images of the brain with the help of three-dimensional electron microscopy. Up until now, however, the mapping of larger areas has been hampered by the fact that, even with considerable support from computers, the analysis of these images by humans would take decades. This has now changed. Scientists from Google AI and the Max Planck Institute of Neurobiology describe a method based on artificial neural networks that is able to reconstruct entire nerve cells with all their elements and connections almost error-free from image stacks. This milestone in the field of automatic data analysis could bring us much closer to mapping and in the long term also understanding brains in their entirety.

Compared to the brain, artificial neural networks use vastly simplified “nerve cells”. Artificial intelligence based on these networks has nevertheless already found countless applications: from self-driving cars to quality control to the diagnosis of disease. However, until now the algorithms were too imprecise for very complex tasks such as the mapping of individual nerve cells with all their ramifications and contact points from a three-dimensional image of a brain.

“The cell structures that the computer generated from our electron microscopy images simply had too many mistakes”, relates Jörgen Kornfeld from the Max Planck Institute of Neurobiology in Martinsried. “In order to be able to work with these data, everything first had to be ‘proofread’.” That would require a lot of work: 11 whole years for an image stack with just 0.1-millimeter edge lengths. “That’s why we needed to find something better”, says Kornfeld. The best tools — at least currently – are the flood-filling networks (FFNs) developed by Michal Januszewski and colleagues at Google AI. A dataset from the brain of a songbird recorded already years earlier by Kornfeld and which he had partially analyzed by hand, played a big role in this development. The few cells that are carefully analyzed by humans represent the ground truth with which the FFNs first learned to recognize what a true structural protrusion looks like. On the basis of what has been learned, the remainder of the dataset can then be mapped with lightning speed.

Collaboration between computer scientists and biologists is nothing new in the department led by Winfried Denk. The leader of the Google research group, Viren Jain, was a PhD student at MIT in 2005 when Denk turned to Jain’s supervisor, Sebastian Seung. Denk wanted Seung’s help with the analysis of datasets generated using a method that had just been developed in Denk’s department. At that time in the department, Kornfeld was engaged in writing a computer program for data visualization and annotation. Kornfeld, whose research increasingly combines neurobiology and data science, was mainly responsible for developing the “SyConn” system for automatic synapse analysis. This system – like the FFNs – will be indispensable for extracting biological insights from the songbird dataset. Denk regards the development of the FFNs as a symbolic turning point in connectomics. The speed of data analysis no longer lags behind that of imaging by electron microscopy.

FFNs are a type of convolutional neural network, a special class of machine learning algorithms. However, FFNs also possess an internal feedback pathway that allows them to build on top of elements that they have already recognized in an image. This makes it significantly easier for the FFN to differentiate internal and external cellular structures on adjacent image elements. During the learning phase the FFN learns not only which staining patterns denote a cell border, but also what form these borders typically have. The expected savings made in terms of time needed for human proofreading through the use of the FFNs certainly justifies, according to Kornfeld, the greater computing power needed in comparison to currently used methods.

It now no longer seems completely inconceivable to record and analyze extremely large datasets, up to an entire mouse or bird brain. “The upscaling will certainly be technically challenging,” says Jörgen Kornfeld, “but in principle we have now demonstrated on a small scale that everything needed for the analysis is available.”
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Za Jul 21, 2018 1:18 pm

 

Fri, 07/20/2018 - 10:51am by The Optical Society

Researchers have shown that it is possible to train artificial neural networks directly on an optical chip. The significant breakthrough demonstrates that an optical circuit can perform a critical function of an electronics-based artificial neural network and could lead to less expensive, faster and more energy efficient ways to perform complex tasks such as speech or image recognition.

"Using an optical chip to perform neural network computations more efficiently than is possible with digital computers could allow more complex problems to be solved," said research team leader Shanhui Fan of Stanford University. "This would enhance the capability of artificial neural networks to perform tasks required for self-driving cars or to formulate an appropriate response to a spoken question, for example. It could also improve our lives in ways we can't imagine now."

An artificial neural network is a type of artificial intelligence that uses connected units to process information in a manner similar to the way the brain processes information. Using these networks to perform a complex task, for instance voice recognition, requires the critical step of training the algorithms to categorize inputs, such as different words.

Although optical artificial neural networks were recently demonstrated experimentally, the training step was performed using a model on a traditional digital computer and the final settings were then imported into the optical circuit. In Optica, The Optical Society's journal for high impact research, Stanford University researchers report a method for training these networks directly in the device by implementing an optical analogue of the 'backpropagation' algorithm, which is the standard way to train conventional neural networks.

"Using a physical device rather than a computer model for training makes the process more accurate," said Tyler W. Hughes, first author of the paper. "Also, because the training step is a very computationally expensive part of the implementation of the neural network, performing this step optically is key to improving the computational efficiency, speed and power consumption of artificial networks."

A light-based network

Although neural network processing is typically performed using a traditional computer, there are significant efforts to design hardware optimized specifically for neural network computing. Optics-based devices are of great interest because they can perform computations in parallel while using less energy than electronic devices.

In the new work, the researchers overcame a significant challenge to implementing an all-optical neural network by designing an optical chip that replicates the way that conventional computers train neural networks.

An artificial neural network can be thought of as a black box with a number of knobs. During the training step, these knobs are each turned a little and then the system is tested to see if the performance of the algorithms improved.

"Our method not only helps predict which direction to turn the knobs but also how much you should turn each knob to get you closer to the desired performance," said Hughes. "Our approach speeds up training significantly, especially for large networks, because we get information about each knob in parallel."

On-chip training

The new training protocol operates on optical circuits with tunable beam splitters that are adjusted by changing the settings of optical phase shifters. Laser beams encoding information to be processed are fired into the optical circuit and carried by optical waveguides through the beam splitters, which are adjusted like knobs to train the neural network algorithms.

In the new training protocol, the laser is first fed through the optical circuit. Upon exiting the device, the difference from the expected outcome is calculated. This information is then used to generate a new light signal, which is sent back through the optical network in the opposite direction. By measuring the optical intensity around each beam splitter during this process, the researchers showed how to detect, in parallel, how the neural network performance will change with respect to each beam splitter's setting. The phase shifter settings can be changed based on this information, and the process may be repeated until the neural network produces the desired outcome.

The researchers tested their training technique with optical simulations by teaching an algorithm to perform complicated functions, such as picking out complex features within a set of points. They found that the optical implementation performed similarly to a conventional computer.

"Our work demonstrates that you can use the laws of physics to implement computer science algorithms," said Fan. "By training these networks in the optical domain, it shows that optical neural network systems could be built to carry out certain functionalities using optics alone."

The researchers plan to further optimize the system and want to use it to implement a practical application of a neural network task. The general approach they designed could be used with various neural network architectures and for other applications such as reconfigurable optics.
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Do Jul 26, 2018 11:13 am

 

Tom Simonite, 07.25.18 07:00 AM

Google Glass lives—and it’s getting smarter.

On Tuesday, Israeli software company Plataine demonstrated a new app for the face-mounted gadget. Aimed at manufacturing workers, it understands spoken language and offers verbal responses. Think of an Amazon Alexa for the factory floor.

Plataine's app points to a future where Glass is enhanced with artificial intelligence, making it more functional and easy to use. With clients including GE, Boeing, and Airbus, Plataine is working to add image-recognition capabilities to its app as well.

The company showed off its Glass tech at a conference in San Francisco devoted to Google's cloud computing business; the app from Plataine was built using AI services provided by Google’s cloud division, and with support from the search giant. Google is betting that charging other companies to tap AI technology developed for its own use can help the cloud business draw customers away from rivals Amazon and Microsoft.

Jennifer Bennett, technical director to Google Cloud’s CTO office, said that adding Google’s cloud services to Glass could help make it a revolutionary tool for workers in situations where a laptop or smartphone would be awkward. “Many of you probably remember Google Glass from the consumer days—it’s baaack,” she said, earning warm laughter, before introducing Plataine’s project. “Glass has become a really interesting technology for the enterprise.”

The session came roughly one year after Google abandoned its attempt to sell consumers on Glass and its eye-level camera and display, which proved controversial due to privacy concerns. Instead, Google relaunched the gadget as a tool for businesses called Google Glass Enterprise Edition. Pilot projects have involved Boeing workers using Glass on helicopter production lines, and doctors wearing it in the examining room.

Anat Karni, product lead at Plataine, slid on a black version of Glass Tuesday to demonstrate the app. She showed how the app could tell a worker clocking in for the day about production issues that require urgent attention, and show useful information for resolving problems on the device's display.

A worker can also talk to Plataine’s app to get help. Karni demonstrated how a worker walking into a storeroom could say “Help me select materials.” The app would respond, verbally and on the display, with what materials would be needed and where they could be found. A worker’s actions could be instantly visible to factory bosses, synced into the software Plataine already provides customers, such as Airbus, to track production operations.

Plataine built its app by plugging Google’s voice-interface service, Dialogflow, into a chatbot-like assistant it had already built. It got support from Google, and also software contractor and Google partner Nagarro. Karni credits Google’s technology—which can understand variations in phrasing, along with terms such as “yesterday” that typically trip up chatbots—for managing a worker’s tasks and needs. “It’s so natural,” she said.

Karni told WIRED that her team is now working with Google Cloud’s AutoML service to add image-recognition capabilities to the app, so it can read barcodes and recognize tools, for example. AutoML, which emerged from Google’s AI research lab, automates some of the work of training a machine learning model. It also has become a flagship of Google’s cloud strategy. The company hopes corporate cloud services will become a major source of revenue, with Google’s expertise in machine learning and computing infrastructure helping other businesses. Diane Greene, the division’s leader, said last summer that she hoped to catch up with Amazon, far and away the market leader, by 2022.

Gillian Hayes, a professor who works on human-computer interaction at University of California at Irvine, said the Plataine project and plugging Google’s AI services into Glass play to the strengths of the controversial hardware. Hayes previously had tested the consumer version of the app as a way to help autistic people navigate social situations. “Spaces like manufacturing floors, where there’s no social norm saying it’s not OK to use this, are the spaces where I think it will do really well,” she added.

Improvements to voice interfaces and image recognition since Glass first appeared—and disappeared—could help give the device a second wind. “Image and voice recognition technology getting better will make wearable devices more functional,” Hayes said.
Gun jezelf wat je een ander toewenst     islam = racisme   & de hel op aarde voor mens en dier
                                   koran = racistisch & handboek voor criminelen
      Moslimlanden bewijzen dagelijks:    meer islam = meer verkrachte mensenrechten

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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Do Jul 26, 2018 8:19 pm

“Toekomst”...

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De Islam is een groot gevaar!
Jezus leeft maar Mohammed is dood (en in de hel)

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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Za Jul 28, 2018 12:15 am

 

By Matthew Hutson, Jul. 27, 2018 , 10:35 AM

Anyone who’s had a frustrating interaction with Siri or Alexa knows that digital assistants just don’t get humans. What they need is what psychologists call theory of mind, an awareness of others’ beliefs and desires. Now, computer scientists have created an artificial intelligence (AI) that can probe the “minds” of other computers and predict their actions, the first step to fluid collaboration among machines—and between machines and people.

“Theory of mind is clearly a crucial ability,” for navigating a world full of other minds says Alison Gopnik, a developmental psychologist at the University of California, Berkeley, who was not involved in the work. By about the age of 4, human children understand that the beliefs of another person may diverge from reality, and that those beliefs can be used to predict the person’s future behavior. Some of today’s computers can label facial expressions such as “happy” or “angry”—a skill associated with theory of mind—but they have little understanding of human emotions or what motivates us.

The new project began as an attempt to get humans to understand computers. Many algorithms used by AI aren’t fully written by programmers, but instead rely on the machine “learning” as it sequentially tackles problems. The resulting computer-generated solutions are often black boxes, with algorithms too complex for human insight to penetrate. So Neil Rabinowitz, a research scientist at DeepMind in London, and colleagues created a theory of mind AI called “ToMnet” and had it observe other AIs to see what it could learn about how they work.

ToMnet comprises three neural networks, each made of small computing elements and connections that learn from experience, loosely resembling the human brain. The first network learns the tendencies of other AIs based on their past actions. The second forms an understanding of their current “beliefs.” And the third takes the output from the other two networks and, depending on the situation, predicts the AI’s next moves.

The AIs under study were simple characters moving around a virtual room collecting colored boxes for points. ToMnet watched the room from above. In one test, there were three “species” of character: One couldn’t see the surrounding room, one couldn’t remember its recent steps, and one could both see and remember. The blind characters tended to follow along walls, the amnesiacs moved to whatever object was closest, and the third species formed subgoals, strategically grabbing objects in a specific order to earn more points. After some training, ToMnet could not only identify a character’s species after just a few steps, but it could also correctly predict its future behavior, researchers reported this month at the International Conference on Machine Learning in Stockholm.

A final test revealed ToMnet could even understand when a character held a false belief, a crucial stage in developing theory of mind in humans and other animals. In this test, one type of character was programmed to be nearsighted; when the computer altered the landscape beyond its vision halfway through the game, ToMnet accurately predicted that it would stick to its original path more frequently than better-sighted characters, who were more likely to adapt.

Gopnik says this study—and another at the conference that suggested AIs can predict other AI’s behavior based on what they know about themselves—are examples of neural networks’ “striking” ability to learn skills on their own. But that still doesn’t put them on the same level as human children, she says, who would likely pass this false-belief task with near-perfect accuracy, even if they had never encountered it before.

Josh Tenenbaum, a psychologist and computer scientist at the Massachusetts Institute of Technology in Cambridge, has also worked on computational models of theory of mind capacities. He says ToMnet infers beliefs more efficiently than his team’s system, which is based on a more abstract form of probabilistic reasoning rather than neural networks. But ToMnet’s understanding is more tightly bound to the contexts in which it’s trained, he adds, making it less able to predict behavior in radically new environments, as his system or even young children can do. In the future, he says, combining approaches might take the field in “really interesting directions.”

Gopnik notes that the kind of social competence computers are developing will improve not only cooperation with humans, but also, perhaps, deception. If a computer understands false beliefs, it may know how to induce them in people. Expect future pokerbots to master the art of bluffing.
Gun jezelf wat je een ander toewenst     islam = racisme   & de hel op aarde voor mens en dier
                                   koran = racistisch & handboek voor criminelen
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Re: Futuristische ontwikkelingen

Berichtdoor xplosive » Di Jul 31, 2018 2:12 pm

 

CBC News · Posted: Jul 25, 2018 3:32 PM MT | Last Updated: July 25

Researchers at the University of Alberta have mastered the art of writing computer memory at the atomic level, a new technology which exceeds the capabilities of current hard drives by 1,000 times.

Using nanotechnology, the team of Edmonton scientists have designed the most dense, solid-state computer memory ever created.

"Essentially, you can take all 45 million songs on iTunes and store them on the surface of one quarter," said Roshan Achal, a PhD student in Department of Physics at the University of Alberta and lead author on a new research study published in Nature Communications.

"Five years ago, this wasn't even something we thought possible."

The technology works at the atomic level and allows for the writing and rewriting of computer data using hydrogen atoms.

The design is perfect to deal with the deluge of information in a data-driven society, Achal said.

Other similar technologies have been developed but only work in very cold, cryogenic conditions. These memory chips, however, are more stable and can withstand temperatures that are room temperature or higher.

Atoms in binary code
"We really have automated this process to make it faster and more reliable to start building these perfect structures," said Achal whose work is supervised by U of A professor Robert Wolkow, a pioneer in nanotechnology.

To create the memory chips, researchers insert a tiny wafer of silicon into what is called a scanning tunnelling microscope, and coat the wafer with hydrogen atoms.

By plucking atom after atom off the surface with a tool similar to a pair of tweezers, they encode the silicon with data binary code, a language of ones and zeros used by computers.

They're building atomic structures with 100 per cent accuracy and memories with a density of 138 terabytes per square inch, Achal said.

"You apply a little bit of voltage, similar to a battery voltage, and you are able to rip that atom right out of there," Achal said.

"This allows us to write by removing the atoms, or rewrite by putting atoms back and removing different atoms."

Rewriting memory
The "ah-ha" moment for Achal and his team came when a fellow graduate student "accidentally" realized that atoms could be replaced and manipulated with the microscope.

That led to the "fun idea" of creating memory, Achal said — but it would be about a year before they perfected the technique.

He anticipates it will be another decade before the process is ready for the commercial market.

It's still a bit too slow and too cumbersome for individual users, Achal said.

"To move atoms, it requires a very precise motor but the trade-off you make for that precision is speed. You can only move so fast with a motor that precise.

"But there are shortcuts people can make and I know there is active research into these types of motors, making them faster and more applicable."

When the time comes, their memory work could help archive massive amounts of internet data, Achal said.

A single silicon wafer could store all published information on sites like Wikipedia, Achal said.

"We're basically laying the foundation for future memory applications."

The paper, titled "Lithography for robust and editable atomic-scale silicon devices and memories", appears in the current issue of Nature Communications.
Gun jezelf wat je een ander toewenst     islam = racisme   & de hel op aarde voor mens en dier
                                   koran = racistisch & handboek voor criminelen
      Moslimlanden bewijzen dagelijks:    meer islam = meer verkrachte mensenrechten

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Re: Futuristische ontwikkelingen

Berichtdoor Ariel » Ma Aug 13, 2018 1:23 pm

Een fietsende robot.

De geest van de wijze richt zich naar rechts, maar de geest van de dwaas naar links.

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Pilgrim
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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Ma Aug 13, 2018 2:01 pm

De evenwichtssturing wordt steeds beter met die dingen, maar nu moeten ze nog goed kunnen lopen op twee benen en handelingen kunnen verrichten zonder om te vallen.
De Islam is een groot gevaar!
Jezus leeft maar Mohammed is dood (en in de hel)

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Re: Futuristische ontwikkelingen

Berichtdoor Pilgrim » Wo Aug 15, 2018 11:06 pm

Doorbraak in kernfusie door stabilisatie van het plasma.

No more zigzags: Scientists uncover mechanism that stabilizes fusion plasmas

July 18, 2018 by John Greenwald, Princeton Plasma Physics Laboratory

Afbeelding
Physicist Isabel Krebs. Credit: Elle Starkman/PPPL Office of Communications

Sawtooth swings—up-and-down ripples found in everything from stock prices on Wall Street to ocean waves—occur periodically in the temperature and density of the plasma that fuels fusion reactions in doughnut-shaped facilities called tokamaks. These swings can sometimes combine with other instabilities in the plasma to produce a perfect storm that halts the reactions. However, some plasmas are free of sawtooth gyrations thanks to a mechanism that has long puzzled physicists.

Researchers at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) have recently produced complex simulations of the process that may show the physics behind this mechanism, which is called "magnetic flux pumping." Unraveling the process could advance the development of fusion energy.

Fusion drives the sun and stars
Fusion, the power that drives the sun and stars, is the fusing of light elements in the form of plasma—the hot, charged state of matter composed of free electrons and atomic nuclei—that generates massive amounts of energy. Scientists are seeking to replicate fusion on Earth for a virtually inexhaustible supply of power to generate electricity.

The flux pumping mechanism limits the current in the core of the plasma that completes the magnetic field that confines the hot, charged gas that produces the reactions. This development, found in some fusion plasmas, keeps the current from becoming strong enough to trigger the sawtooth instability.

Spearheading the research that uncovered the process was physicist Isabel Krebs, lead author of a Physics of Plasmas paper describing the mechanism that was published last September and made into a DOE Office of Science highlight in June that summarizes the findings. Krebs, a post-doctoral associate, used the PPPL-developed M3D-C1 code to simulate the process on the high-performance computer cluster at PPPL, working closely with theoretical physicists Stephen Jardin and Nate Ferraro, developers of the code. "The mechanism behind magnetic flux pumping had not been understood," Jardin said. "Isabel's paper describes the process."

Hybrid scenarios
In the PPPL simulations, magnetic flux pumping develops in "hybrid scenarios" that exist between standard regimes—which include high-confinement (H-mode) and low-confinement (L-mode) plasmas—and advanced scenarios in which the plasma operates in a steady state. In hybrid scenarios, the current remains flat in the core of the plasma while the pressure of the plasma stays sufficiently high.

This combination creates what is called "a quasi-interchange mode" that acts like a mixer that stirs up the plasma while deforming the magnetic field. The mixer produces a powerful effect that maintains the flatness of the current and prevents the sawtooth instability from forming. A similar process maintains the magnetic field that protects the Earth from cosmic rays, with the molten liquid in the iron core of the planet serving as mixer.

The mechanism also regulates itself, as the simulations show. If the flux pumping grows too strong, the current in the core of the plasma stays "just below the threshold for the sawtooth instability," according to Krebs. By remaining below the threshold, the current keeps the plasma temperature and density from zigzagging up and down.

The simulations could lead to measures to avoid the troublesome swings. "This mechanism may be of considerable interest for future large-scale fusion experiments such as ITER," Krebs said. For ITER, the major international fusion experiment under construction in France, creation of a hybrid scenario could produce flux pumping and deter sawtooth instabilities.

One way to develop the hybrid scenario will be for operators of ITER to experiment with the timing of the neutral beam power that will heat the ITER plasma to fusion temperatures. Such experiments could lead to the combination of plasma current and pressure that produces sawtooth-free operation.

https://m.phys.org/news/2018-07-zigzags ... lizes.html
De Islam is een groot gevaar!
Jezus leeft maar Mohammed is dood (en in de hel)


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