The equation looks more akin to inductance to me ([tex]L=\frac{d\Phi_{m}}{dq/dt}[/tex]). It appears that the defining feature of the memristor is that it has some memory of the past current so that the memory resistance is a function of both present and past current rather than just current.nathan.br said:Isn't this equation equivalent to a regular resistor? R = dv/di?
wolram said:May be instead of having to (reset) a machine this device would remember where it stopped and carry on from there.
It is impossible to construct a device from any combination of resistor, capacitor, and inductor that will output a hysteresis loop. This according to R. Stanley Williams of Hewlett Packard here:TheAnalogKid83 said:my only question is to this being a "fundamental" property like resistance, inductance, and capacitance. It sounds like a special type of resistor rather than a separate property. Why do we mathematically model transmission lines, components, and all other electrical characteristics only with resistance, inductance, and capacitance, but not with memristance? Is it really valid to say its a fundamental component? I guess if its a passive device, it seems more believable to be fundamental, but it still had to be created artificially in a lab, whereas the other properties show up everywhere naturally.
The effect of the platinum on either side of a doped and non-doped center of Titanium dioxide let's the boundary move under the influence of a voltage thus altering resistance. The effect occurs over time and is quite sensitive to voltage once the voltage is high enough, but not so high that the device self destructs. At the quicker switching rates the device is said to have a "geologic" lifetime.ynot said:There are only two things that I can think of that one can argue to make it "fundamental".
1. Mathematically - that was Leon Chua's first idea that it was necessary. It was the fourth leg, based on the relationships of the ratios of fluxes, charges, etc.
2. It will explain hysteresis that exists everywhere.
However, these are the similar things that were claimed for Chaos Theory a few years ago (don't get me started on Fuzzy Logic). I think Dr. Chua has a few papers on Chaos theory, by the way. (Chaos explained nonlinearity everywhere, gee, that's really helped.)
I think it's a neat device, I share TheAnalogKid's skepticism about the fundamental claims, just because I just somehow don't see it suddenly being something that I've been needing in my modeling. Not just yet.
You may be able to program the hysteresis loop that is characteristic of the memristor. Chou presented this loop as the characteristic output of the memristor to balance the output of the other three basic electronic elements, capacitor, inductor, resistor. If you believe HP's head of memristor research, the memristor would be whatever it is that gave that hysteresis loop, no matter whether created by a program or an assembly of elements as Hewlett Packard has done with titanium and others are doing with silicon, though with silicon the 10,000 cycle limit would likely limit its application to thumb drives at its present state of development. The titanium iteration has no known cycle limits but is more expensive.603nothing said:I'm thinking of doing some in depth research for a school project on the memristor, does anybody have any input on whether or not this is a good idea? The reason I ask is because since there are little to no available consumer memristors out there, my project would be solely research, mathematics, fancy poster boards and I would really have very little to show for it. It's a very interesting topic to me and I feel like if I follow through my senior year as an undergrad I may be able to make more sense out of the topic and perhaps do a year of graduate school based on this component and more in depth research.
Thoughts?
The future of programming the new memorized resistance units will need to be developed to take advantage of the reduced component count and the proportional density increase in computing capacity. Presently their is a trend to http://emotion.inrialpes.fr/BP/" [Broken]603nothing said:Thanks for the reply, while this is or at least will be an important topic in the near future, I just want to start to focus my studies on the non-linear properties this component has. I know in many SPICE simulators you can define components based upon mathematical equations, which is hopefully what I will be doing. As for the programming half, I've worked with a few MATLAB explanations and models for the memristor's qualities and I've got to say this is some really interesting stuff.
I'm not the one to be asking about calculus. You could be right, just that I'm not able to tell your intent since I couldn't pass it to keep my *** out of 'Nam. In a human endeavor that uses reason the use of logic involving only three conditions has been available in the raw materials of computer construction. The binary conditions of true or not true, or indeterminate (overuns, does not compute failures.) Whereas the real world is one of dynamic uncertainty exemplified by the condition known as turbulence, that has some expression in the pop Butterfly Effect. There is just to much data at fine levels to be analyzed and so statistical states must be used. Quantum theory has this down to a, hmm, science.603nothing said:So...he's saying that it would be possible for me to determine a person's logic by statistically doing calculus? And then assimilating that with memristance logic? I'm not quite sure I understood that or how it would go for a project.
minorwork said:I'm not the one to be asking about calculus. You could be right, just that I'm not able to tell your intent since I couldn't pass it to keep my *** out of 'Nam. In a human endeavor that uses reason the use of logic involving only three conditions has been available in the raw materials of computer construction. The binary conditions of true or not true, or indeterminate (overuns, does not compute failures.) Whereas the real world is one of dynamic uncertainty exemplified by the condition known as turbulence, that has some expression in the pop Butterfly Effect. There is just to much data at fine levels to be analyzed and so statistical states must be used. Quantum theory has this down to a, hmm, science.
What I think Maxwell is saying, and it addresses the problems with any field type theory, is that any equation must be NOT of simple yes or no algorithms but must be expressed in terms of probabilities. This is very relevant to a lot more than scientific endeavors. In our courts a jury that does not understand the subtleties of Bayesian logic can be fooled into thinking DNA evidence and other probability expressions are of the simple yes or no propositions and can even be tricked by unscrupulous or ignorant attorneys. Even few doctors know how to figure the real odds that a certain test shows you have of having a disease based on the error rates and full analysis of the testing procedures. Best read on Bayesian analysis and examples in the medical field as well as Bayesian logic that deals with probabilities. Bayesian reasoning often is counter to "common sense" logic.
Say you know a family has two children, and further that at least one of them is a girl. What is the probability that they have two girls? Boy/girl, girl/boy, and girl/girl give a .33 chance (1 in 3) that at least one is a girl. How then does the fact that the one girl that they do have is named Florida alter the chances to .5 (1 in two?) http://bblais.blogspot.com/2010/01/there-once-was-girl-named-florida-aka.html
The memristive type computer is inherently a probability computer when fully realized. There are other efforts in the same area to get rid of the right wrong dualities that digital computers have so far relied on programming schemes to counter.
If it was easy there'd be 9 year olds doing it.603nothing said:Alright thank you, that made a bit more sense, at least from how I understood it. Simple gate logic today is solely based on, zeros and ones, however this new non-linear component (memristor) shows for itself that this 1 & 0 (and X,Z...) is not true logic of this world. The extra probabilities, say for example past current and voltage levels across the memristor are what will truly reason with the next event(s)?
This makes much more sense when trying to figure out how to tie human logic into these memristors, I'll for sure be reading up on some Bayesian reasoning. So for the calculus based within a memristance function, which bases its current state on past differentials of the sort and those "extra probabilities," it must be safe to say that the human brain functions remarkably close to that of a memristor's function if all that is behind true world reasoning and logic is the calculus behind probability.
Since a memristor isn't linear, these changes are going to be some sort of function between current and voltage which are also past events. Similar to this is human logic, also based upon past events but is human logic based upon probabilities? I can't even think in that magnitude right now...
You got me. You want a project. Get a Wofram Mathematica 7 memristor simulator going and somehow see if you can have the output feed the input to another instance of Mathematica and see if you can get the damn thing to play a half *** competent game of tic-tac-toe. In other words how do you program a memristor circuit analog computer? Can you make two memristors do addition? Or do you only need one? http://demonstrations.wolfram.com/CurrentVoltageCharacteristicsOfAMemristor/603nothing said:bump :)
minorwork said:You got me. You want a project. Get a Wofram Mathematica 7 memristor simulator going and somehow see if you can have the output feed the input to another instance of Mathematica and see if you can get the damn thing to play a half *** competent game of tic-tac-toe. In other words how do you program a memristor circuit analog computer? Can you make two memristors do addition? Or do you only need one? http://demonstrations.wolfram.com/CurrentVoltageCharacteristicsOfAMemristor/
It also seems like I've seen an active circuit configured to achieve the hysteresis loop but it was pretty complicated and I can't seem to find it now.
If the loop can be simulated with hydraulics then you could make a column of water trip some check valves and hold a level in tube depending on the pressure (voltage) of the water or oil in a hydraulic simulation of a memristor. A cork with a magnetic could be the sensor of the level (height) of the water column which position was read as an output by a series of reed switches up the column and could digitize the position of the column onto a graphing program. You could then talk about how the memristor works in a voltage range low enough that it won't short out, (blow up a balloon or fragile light bulb representation that high pressure would rupture, thus emulating a high voltage insulation breakdown in electric conductors.
I'm thinking a hydraulic representation would be a visual with colored fluids in transparent tubes with check valve spring calibrated by spring tensions to allow pressure into the tube and alter the floats position.
Enough for you to get started? Just make the levels of one, two, or three tubes change in accordance with the Mathematica simulator by adjusting spring values and such and the positions of the floats be in front of a scale(like on a thermometer) that when adding three columns values would give a result or better have a fourth column connected to the base of the three columns "read" the pressures of the column height and achieve the additive of those, perhaps on a logarithmic readout or straight 1:1. Whatever, you'll have to adapt.
No sweat. I'm retired from the coal mine and have some time. My college is limited to some physics in my minor of general science, my BA is in philosophy.603nothing said:Thanks minorwork, those are all very good suggestions. After reading the latter over a couple of times some ideas started popping into my head, such as using Labview for a differential simulation export, and using some sort of FPGA to control the external visual whether it be a tube-based water system or perhaps a radio's volume? Even as simple as rows of LEDs which illuminate 1:1 with kOhms of resistance.
Those are just a few I thought of quickly, since this is turning more into an emulation there is room for cleverness. I'm going to keep a note pad with me and think of some ideas over the next bit. Thanks for the help it is appreciated, suggestions welcome, of course.
http://news.sciencemag.org/sciencenow/2011/03/memristors-make-fast-work-of-maz.html [Broken]Yuriy Pershin of the University of South Carolina, Columbia, and Massimiliano Di Ventra of the University of California, San Diego, claim to have developed the first parallel way to automatically solve mazes. Their method relies on an electronic device called a memristor which was first created in 2008 by a group at HP Labs in Palo Alto, California. Like its cousin the resistor, a memristor hinders the flow of electric current, but it also has an internal memory that can reveal how much current has flowed through it in the past.
Pershin and Di Ventra's scheme is to replicate an ordinary maze of vertical and horizontal pathways with a grid of many—hundreds or perhaps thousands—interconnected memristors. Where there are walls, Pershin and Di Ventra switch off the corresponding interconnection so that the memristor grid is left with pathways corresponding to those on the original maze. The same grid could be used again for different mazes by resetting the interconnections.
The trick comes when the researchers apply a voltage across the grid's entrance and exit. This prompts a current to flow, but it can only go along paths that have no dead ends—that is, it can take paths that lead only to the exit. What's more, it flows faster through the shortest routes because those contain the fewest memristors. Pershin and Di Ventra can then simply tap into the memory states of all the memristors, which have recorded the current levels through them, to discover which are the shortest routes.