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Right now, in 2022, we can read with perfect understanding mathematical articles and books
written a century ago. It is indeed remarkable how the way we do mathematics has stabilised.
The difference between the mathematics of 1922 and 2022 is small compared to that between the mathematics of 1922 and 1822.
Looking beyond classical ZFC-based mathematics, a tremendous amount of effort has been put
into formalising all areas of mathematics within the framework of program-language implementations (for instance Coq, Agda) of the univalent extension of dependent type theory (homotopy type theory).
But Coq and Agda are complex programs which depend on other programs (OCaml and Haskell) and frameworks (for instance operating systems and C libraries) to function. In the future if we have new CPU architectures then
Coq and Agda would have to be compiled again. OCaml and Haskell would have to be compiled again.
Both software and operating systems are rapidly changing and have always been so. What is here today is deprecated tomorrow.
My question is: what guarantee do we have that the huge libraries of the current formal mathematics projects in Agda, Coq or other languages will still be relevant or even "runnable" (for instance type-checkable) without having to resort to emulators and computer archaeology 10, 20, 50 or 100 years from now ?
10 years from now will Agda be backwards compatible enough to still recognise
current Agda files ?
Have there been any organised efforts to guarantee permanent backward compatibility for all future versions of Agda and Coq ? Or OCaml and Haskell ?
Perhaps the formal mathematics project should be carried out within a meta-programing language, a simpler more abstract framework (with a uniform syntax) comprehensible at once to logicians, mathematicians and programers and which can be converted automatically into the latest version of Agda or Coq ?
Let P(z) denote the (rational) transfer function of an nD system, where z=(z1,...,zn), of a spatial-temporal discrete recurrence Givone-Roesser type system or Fornasini-Marchesini type system. Assume that P(z)2=P(z) for any z as above.
1. Can we prove that P(z) is stable? meaning that all the P(z) entries have denominators with no zeros in the open polydisk D^n (assuming that in each entry n(z)/d(z) the numerator n(z) and the denominator d(z) are relatively prime).
2. Can we prove that is structurally stable? meaning that all the P(z) entries have denominators with no zeros in the closed polydisk (assuming that in each entry n(z)/d(z) the numerator n(z) and the denominator d(z) are relatively prime).
Many Thanks!
Dear friends
Thank you in advance for your help and collaboration. Here in my lab we are working on a photosynthetic plant and we have a non-linear subactuated bilinear model (attached image with the model). The u(t) (dilution rate), the two output variables are x1(biomass) and x3 (volume), alpha1,2 are positive constants and a1,2 are constants. E(t) is a bounded disturbance.
In this type of systems it is necessary to obtain a system in its canonical form (chain of integrators), to be able to propose a Sliding Mode array control?
How would you implement a sliding mode system in this type of systems?
Thank you in advance, if you are also interested in collaborating with the multidisciplinary working group, write to me at aerodriguez@conacyt.mx
Kind regards

My current research involves the impact of culverts on the distribution of a salamander species, and I am attempting to include road usage levels in the analysis. I cannot find any sources for good road use estimation methods.
Google and other giant tech company has already introduced such types of system .
Is it possible to derive the theoretical formulation for rotating cantilever beam as force is a function of rotating speed or displacement.
Suppose 1000 rpm applied, during rotation, the beam vibrating and deflects at some frequency.
Deflection is caused in the beam due to rotational motion, similar to deflection is caused in the beam due to tip excitation, base excitation(force relations are there for this excitation source and FEM simulation is also done for this type of system)
For rotational system, how can i apply a force as a function of rotational speed in the Finite Element Analysis
Most countries have some type of system to forecast crops related information to the farmers. But most of time information are generic to the geographical region rather atmospheric regions. Hence many farmers loss their crops and investments due to unpredictable weather, soil, water and seeds compatibility and feasibility etc and inaccurate information due to no time-bound delivery of information.
In result, in the world, thousands and thousands of farmers are going for suicide every year. This is much bigger figure than majority of wards of the world.
Is artificial intelligence based adaptive mathematical model possible to quickly forecast best crops for the farmers every month and in case any drastic chance in weather soil or seeds, farmers should be able to go choose plan B to reduce the effects of surprises.
PACS systems are nowadays ubiquotous in developed countries. However, quite often DICOM images can be seen in one institution only a and the ways to share these results between different institutions are limited to CD/DVD sharing.
Is there a cloud/mail/other type of system to share DICOM images in your country?
There are many types of systems in the bacteriological laboratory are used for identification of bacteria Pseudomonas spp. which one is gratified.
Hi eyeryone,
I have problem to determine CMC in mixed type systems i mean :different ratio of concetration of cationic surfactants. I use a conductometric titration to measure it. But i cannot obtain any repeatable data. My compounds are quaternary ammonium salts with different alkyl chain length. I hope that someone has experience in that field.
Thanks in advance,
Marta
In the books "Energy Harvesting Systems" and "Piezoelectric Energy Harvesting" I have seen different models for the description of cantilever type systems. I would like someone to explain the differences to me, or advise me some article that talks about it.
to choose type of system for ammonia water
Hello Researchers,
I want to model natural filler or fiber molecular dynamics on polymer composites. Can I get any clue for modelling this type of system? what type of force field I can use.
Since Java is included in that range, I'm curious about Scala.
Note that Scala is more difficult to analyze than Java for several reasons, including but not limited to:
- Compile-time code generation (e.g., macros)
- Expressive type system
A non-minimum phase system is difficult to control because of RHP zeros. How to deal with this type of system?
Hi everybody,
How can I design a back stepping controller for this system? h1 and h2 are states of the system and q is the input.
Because, in Khalil's book, design is said for specific type of systems.

The optimal control of hybrid photovoltaic/thermal systems is complex due to the opposite optimal operation points of the two separated systems.
In fact, to increase the efficiency of a photovoltaic module is needed to decrease its temperature, whereas to increase the efficiency of the thermal part is necessary to increase the temperature of the fluid (in our case water). Of course the control variable can be the flow rate of the water, but the range of variation of the flow rate is quite narrow. I would like to contact researchers that work experimentally on this subject.