Science topic

Modelisation - Science topic

Explore the latest questions and answers in Modelisation, and find Modelisation experts.
Questions related to Modelisation
  • asked a question related to Modelisation
Question
5 answers
I'm working on Greenhouse Climate control Using the Fuzzy Logic Controller, so I'm searching for the mathematic model of Greenhouse structure, and the heater, cooler, and humifier transfer functions .
Relevant answer
Answer
I hope that the following 5 papers are interesting
1-SE—Structures and Environment: A Strategy for Greenhouse Climate Control, Part I: Model Development
M. Trigui, S. Barrington, L. Gauthier
Journal:
Journal of Agricultural Engineering Research
Year:
2001
2-Review of Structural and Functional Characteristics of Greenhouses in European Union Countries: Part I, Design Requirements
B. von Elsner, D. Briassoulis, D. Waaijenberg, A. Mistriotis, Chr. von Zabeltitz, J. Gratraud, G. Russo, R. Suay-Cortes
Journal:
Journal of Agricultural Engineering Research
Year:
2000
3-Assessment of the greenhouse climate with a new packed-bed solar air heater at night, in Tunisia
Bouadila, Salwa, Lazaar, Mariem, Skouri, Safa, Kooli, Sami, Farhat, Abdelhamid
Journal:
Renewable and Sustainable Energy Reviews
Year:
2014
4-Mass-Heater Supplemented Greenhouse Dryer for Post-Harvest Preservation in Developing Countries
P. Akinjiola, Olutoye, Balachandran, Uthamalingam (Balu)
Journal:
Journal of Sustainable Development
Year:
2012
5-Greenhouse heating by solar air heaters on the roof
Joudi, Khalid A., Farhan, Ammar A.
Journal:
Renewable Energy
Year:
2014
  • asked a question related to Modelisation
Question
5 answers
Is there any relationship between geologic or hydro-geologic domains (eg. sedimentary) and a range of rock strength or hardness?
Is it possible to rank geological domains on ranges of rock strengths?
Relevant answer
Answer
Hi Amaury,
There is not a classification for your case but there is definitely a relationship between rocks' hardness and strength with hydrological interactions. The main process in this regard is water-rock interactions which is strong in soft rock types and the host rocks with high amount of cracks and interaction surface.
  • asked a question related to Modelisation
Question
3 answers
Hello,
I would like to calculate Fluidization minimum speed velocity (Umf) and Archimede Number for a continous air bed.
I know
  • volumic masses of gaz (=1,14 kg/M^3) and particule (=500kg/M3),
  • viscosity of gaz (= 1.8**-5 Pa.s)
  • diameter of particules (0,000484 m)
I can't know the porosity.
Also, I've determine experimentaly the Umf (0,4 m/s) . Now I would like to calculate it in order to extrapolate it with other particules types.
Does anyone knows what kind of formula I should use, or maybe an modelisation could be efficiant ?
many thanks in advance,
Regards.
Relevant answer
Answer
Juliette Parrott, Romankov equation, given as an example, does not take into account the shape of the particle. There are others that include not only the particle shape. Using e.g. Leva equation for pressure drop, one can obtain the critical velocity (umf) equation taking into account the shape factor. Obviously, the problem is the porosity of the bed corresponding to critical velocity. It should also be remembered that the error of the values ​​calculated with the criteria equations can be as much as 30%.
  • asked a question related to Modelisation
Question
1 answer
I am using MIDAS GTS NX to simulate an urban tunnel excavation with NATM method, the tunnel wizard option in the program allows to simulate the rockbolts but it does not allow to model the pre-reinforcement of the umbrella pipes.
should i create it manually or simualte it by inclined rockbolts !
has anyone done this model before ?
Relevant answer
Answer
I recommend you to model the umbrella pipes in a cad software, and then import it into MIDAS GTS-NX. It's easier than you think.
There's a video about this in MIDAS' YouTube channel: https://www.youtube.com/watch?v=ZHi_A6aJM88
Hope this helps you.
Bye, Felipe.
  • asked a question related to Modelisation
Question
4 answers
Hello researchers,
I am a PHD student , working on shape memory alloys modelisation using Ansys softwar.
I need to know and to understand the theorical part of ansys in dealing with SMA, wich equations did it uses? please share documentation if you have.
Thank you
Relevant answer
Answer
In Abaqus we can define our own material models so that new materials could also be simulated. Abaqus also provides a good collection of multiphysics capabilities, such as coupled acoustic-structural, piezoelectric, and structural-pore capabilities. So it is used for multi field/department materials. Abaqus was initially designed to address non-linear physical behavior; as a result, the package has an extensive range of material models such as elastomeric and hyperelastic material capabilities. But ACP is intuitive and easy, So try on ACP first then go for Abaqus.
  • asked a question related to Modelisation
Question
6 answers
Dear colleagues, do you have any idea about the advances on phytochemistry especially the use of informatics for chemical studies, and biological activities molecular interactions modelisations, and is there any other applications of informatics on this field. Thank you
Relevant answer
Answer
Informatics study on natural products chemistry is possible but you should know about phytochemicals , then individual separation .Then apply the informatics to study the bioactivity.
  • asked a question related to Modelisation
Question
4 answers
i have a mathematical model of the controller placement problem and i want to write a program using C as a language of programming,
this program he can find the optimal number of controllers that must installed in a Software Defined Network (SDN) and i don't know how to model the of switcher and the set of controllers in this program.
Relevant answer
Answer
This paper may help you:
  • asked a question related to Modelisation
Question
3 answers
I'm working on earthquakes energy modelizations around faults under Windows 10.
Here's the problem: I need Coulomb to modelize shear / normal / coulomb stress, but it isn't (correctly) working on Octave (which's a free and open source equivalent of MATLAB, and that I've downloaded on my personnal computer at home; we only have MATLAB in the uni room).
Does anyone know a way to make Coulomb work properly on Octave, for a home-work situation? Or know an equivalent to Coulomb which would work well on Octave?
Or do I have to buy a MATLAB student license?
I thought of mailing my university to ask for a MATLAB student license, but the situation is administratively already quite complicated because of the COVID-19, so I tried to fend for myself and I couldn't find anything for the moment.
Thank you all!
Relevant answer
Answer
Please visit the following link below:
  • asked a question related to Modelisation
Question
5 answers
my researches are about assasing impacts os xénobiotic on Daphnia magna but I would like to use modelesation and learning more about, can you help me to clarify or provide somme data about modelisation using daphnia as a model
Relevant answer
Answer
Zhiquan Liu exactly yes that's it
  • asked a question related to Modelisation
Question
7 answers
Hello, i look for an example to model an energy management system for a building microgrid with hybrid renewable sources in matlab simulink or other software. I would be grateful to receive your proposal at: ouassima.boqtob@usmba.ac.ma.
Thank you.
Relevant answer
Answer
  • asked a question related to Modelisation
Question
5 answers
Hello,
Is someone know if it's possible from a crystallized protein modelisation to know the distance between X and Y amino acid? Which softwares/ websites to consider?
Thanks a lot in advance.
Alice
Relevant answer
Answer
Thank you very much for your answers! I will try the different approaches and will get back to you.
  • asked a question related to Modelisation
Question
2 answers
Actually, I didn't know how to modelise the behavior of this hyperelastic layer when I'm simulating , the hyperelastic layer is incompressible I want to know how can I add a dynamic relaxation?
Thank u
Hniya
Relevant answer
Answer
No I haven't done any diagram why shold I do it ?
  • asked a question related to Modelisation
Question
1 answer
i want a precise description of BHA equipement and tools in oil and gas industry to find a way to modelise them in a databse .
already checked some articles and WITSML data description but couldn't figure out the necessary attribute in this industry.
thank's in advence
Relevant answer
Answer
¿Can you explain with more detail your problem?
  • asked a question related to Modelisation
Question
2 answers
je cherche la modélisation de systéme biomasse ( gazification ) en MATLAB/SIMULINK , spécifiquemen simulink model of the gasifier et le Block diagram of the gasifier control system
Relevant answer
Answer
je vous remercie Mohamed-Mourad Lafifi
  • asked a question related to Modelisation
Question
4 answers
Hi All,
I have 8 samples of Input/Output from which i should create a model of the system to control its output. Using the transfer function makes no sense for me because my data is stationary, the output depends only of the values of the input. How should I proceed in this case and what kind of modelisation fits the best?
Thank you in advance.
Relevant answer
Answer
I used the quick start in Sys. Identification, it gave me a discrete time state space model that fits 100%, but in simulation i get very wrong values of the ouput..i dont understand why..please some help would be very appreciated
  • asked a question related to Modelisation
Question
9 answers
complex systems / complex adaptive systems
Relevant answer
Answer
After a large study of different complex systems based methods I'm considering to use graph theory and network theory to analyze urban street patterns (based on toplogical indicators).
Among these software tools ArcGIS and NetworkX which do you recommand to use?, what are your suggestions beyond this set ?
  • asked a question related to Modelisation
Question
4 answers
I wonder which of, calculation and computation, data analysis or modelisation is the more efficient for individual housing neighborhood under land shortage and profit based renewal unbalancing social infrastructure along with housing typology, engendering a significant gentrification.
Relevant answer
Answer
Federico Zanfi (Politechnico die Milano) presented Italian traditions in single-family housing and an analysis of three case studies. The presentation was prepared in cooperation with Chiara Merlini. In Italy, freestanding small houses are not necessarily inhabited by a single core family, but by an extended, multigenerational family with different household structures. Therefore, the number of two-family houses is high compared to other countries. Zanfi referred to three case studies from different Italian regions (Lombardy, Marche and Puglia) to illustrate the phenomenon of “diffuse urbanisation” and arising challenges: SFH in industrial zones, SFH in tourist area and self-built low-cost houses in areas of endogenous growth in small suburban centres. In Japan after 30 years the value of a house deceases towards zero (from point of finance), while the lot retains its value. Murayama described urban shrinkage as a complex process of transformation. As a provisional conclusion, we emphasize the need – at least in a country like Italy, which includes extremely different territorial frameworks – to study family-houses framing them into specific dynamics of social and economic transformation. We proposed to look at this building type at least through three of its main inflections: First, the family-house that embodies the endogenous growth of small centres, and the simultaneous escape from the main metropolitan areas in the richest (and more congested) region of the country; Second, the family-house nested in “peripheral” industrial district economies, which are now experiencing profound reorganization; Finally, the family-house that is the outcome of a self-organized tourist sector now suffering from competition with other Mediterranean countries. In perspective, it would be interesting – within the transformation parables that we have briefly sketched – to investigate family-house considering it not only as a burden that is not easy to manage, or else a source of conflict between generations. A pragmatic reflection in a moment of crisis and insecurity on future welfare provisions may suggest to look at these houses as potential resources – often the only resource available – and therefore it would be urgent to understand at which conditions – which tenure innovations, which performance improvements, which typological adjustments – we can assume to go on using them.
  • asked a question related to Modelisation
Question
2 answers
I have a problem in the calculation of equivalent circuit of an FSS ring structure, it can be modelised by using an LC circuit, to calculate LC i use the hypothise of the mutual inductance between two parallel wire but it's not working according to the resonance frequency that i get by simulation (f0=1/2*pi*L*C).
Relevant answer
Answer
Thank you Dwivedi.
  • asked a question related to Modelisation
Question
5 answers
Hello Guys,
i have a little experience in star ccm+ modelisation.
So now i have to modelize Panning hull in star ccm, to determine the drag,pression and trim....
My problem is to design a good "mesh" so i can have results that can be good enough.
Here, i saw a lot of publications about that, but i can't find none explicite about how to chose a suitable high of cells....
Another question is the type of cells: What is the best between the polyhedral and the trimmed mesh? (i often use the Trimmed mesh).
Thank in advance for your answers.
Relevant answer
Answer
KCS model is in Tutorial Guide in motion you can see find that.
for validate a prism layer you can validation with empirical results or Y+ range or VOF scheme. for total thickness, use the bondary layer formolation is better.
Best Regards
  • asked a question related to Modelisation
Question
5 answers
In the ENVI-met models what type of soil should we put under the buildings????
Relevant answer
Answer
As far as I know, Yes. For more information, ask your question on the software forum.
  • asked a question related to Modelisation
Question
3 answers
Hello,
I took example over the example of GaAs junction in matlab to try to modelise my own laser. However i got the following error:
"Unknown function or operator. - Name: n_interp"
and i don't know what i could do to solve it.
Thank in advance.
Matthias
Relevant answer
Answer
When you installed the software, it's possible that library files have not correctly carried out. Also, check your license via COMSOL portal.
  • asked a question related to Modelisation
Question
3 answers
I downloaded French language paper Modelisation de la rupture et de la reformation des films lubrifiants dans les contacts elastohydrodynamiques but my French isn't good enough to be able to understand tecnical data
Relevant answer
Answer
Hi! I recommend deepl. It's the best online translator by far.
  • asked a question related to Modelisation
Question
5 answers
The likelihood ratio test of comparing reduced model with full model differs by fixed factor result to chi-square distribution of zero degree of freedom.
/* reduced model */
proc mixed method = ml;
class block gen;
model rtwt = /ddfm = kr;
random block gen;
run;
/* full model*/
proc mixed method = ml;
class block gen;
model rtwt = prop_hav/ddfm = kr;
random block gen;
run;
There are 3 degree of freedom from reduced model - block variance, genotype variance, and residual variance. The same degree of freedom for full model with includes prop_hav as covariate. The difference in their -2 loglikelihood has zero degree of freedom under chi-distribution. Please could anyone guide me on how to compare these model to ascertain if the full modelis significantly different from reduced model.
Relevant answer
Answer
LRT only works when one model is a simplification of another. You can’t take out terms and add in with one go, do it in two stages.
the models to be compared must be nested
  • asked a question related to Modelisation
Question
2 answers
Salut communauté,
c'est ma première participation, et mon premier travail de recherche,
J'ai besoin d'aides pour appliquer la méthode Pushover sur un barrage poids via le logiciel Sap 2000, surtout comment introduire les zones non linaires (joint de reprise).
une réponse généreuse détaillant les étapes à suivre pour modéliser un barrage poids est très souhaitable.
Je vous remercie d'avance.
Relevant answer
Answer
thank your Mr MIGUEL
  • asked a question related to Modelisation
Question
7 answers
What is the method do you used for the modelisation ?
Relevant answer
Answer
I'm using finite difference method using Fortran.
  • asked a question related to Modelisation
Question
2 answers
Hi,
I modelise a three point bending test on a a beam on ABAQUS. I used a linear displacement applied on a central edge on the top surface of the beam. In the viewing results, a sinking appears at the edge place. Is it correct to modelise a three-point bending load with a linear displacement ?
Thanks,
Yann 
Relevant answer
Answer
Dear Yann,
A 3 point bending is a bending around 3 points, where one point is in the middle on one side, and the two other points are on the other side.
It is used in LEFM to study CTOD.
Then, often a sinking appears at the crack tip, because apparantly  for e.g. steel, the Poisson's ratio is more towards 0.5(instead of 0.3), or how to express it, at that location where the crack propagates, preceeded by plasticity in a very small region.
Did you apply additional displacement? 
Kind regards 
  • asked a question related to Modelisation
Question
1 answer
The result is simply an algebraic equation (exponential form).
Relevant answer
Answer
The question is badly posed. When asking questions, please pose them as clearly as possible! And posing a question the right way is already the beginning of a good answer.
  • asked a question related to Modelisation
Question
2 answers
I did modelisation of an ultrasonic wave with FDTD 2D (Water-Bone).
I put a ponctuel source (velocity or stress) and I tried to capture the L wave or the S wave in another point of my simulation domain.
Relevant answer
Answer
The energy velocity of a wave is the ratio between the power flux (Poynting vector in electromagnetism) and the stored energy density and this should work for sound waves as well. 
  • asked a question related to Modelisation
Question
4 answers
I have a coil tube (in which circulates a heating fluid at high temperature) embedded in a solid material bed at room temperature. Apart from heat transfer coefficients, which other parameters are relevant to describe heat and mass transfer?
Relevant answer
Answer
Samnaw2001@yahoo.fr mail de achour sami