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Model selection and modeling using MATLAB
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Health assessment of lithium batteries can be done by modeling the behavior of the battery over time, including its capacity degradation, voltage, and temperature changes. MATLAB is a powerful tool that can be used to model the behavior of lithium batteries and assess their health. Here are some steps you can take to model lithium batteries using MATLAB:
  1. Data collection: Collect data on the behavior of the lithium battery over time, including its capacity degradation, voltage, and temperature changes.
  2. Model selection: Select a suitable model for the behavior of the lithium battery. Some commonly used models include the empirical equivalent circuit model, the physics-based electrochemical model, and the empirical statistical model.
  3. Model implementation: Implement the selected model using MATLAB. This may involve developing code to simulate the behavior of the battery based on the data collected in step 1.
  4. Model validation: Validate the model using experimental data. This can be done by comparing the model's predictions to actual data collected from the battery.
  5. Health assessment: Use the model to assess the health of the lithium battery over time. This can involve tracking changes in capacity, voltage, and temperature, as well as identifying any anomalous behavior that may indicate a problem with the battery.
In order to model lithium batteries using MATLAB, it is important to have a strong understanding of battery behavior and modeling techniques. It may be helpful to consult with an expert in this field to ensure that your model is accurate and effective for health assessment of lithium batteries.
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For Modeling of Visco-Elastic Damper using link element in SAP2000, how can I get visco-elastic behaviour to the element.
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SAP2000 includes a wide variety of link objects that can be employed to model viscoelastic behaviour. For instance you can use “Damper - linear” or “Damper - exponential” that enable the definition of both stiffness and damping, in the model, based on Maxwell damper that consists of a spring and a dashpot damper connected in-series.
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Hello,
Can anyone suggest books/projects understand from basics about the grid following and grid forming inverters control in a microgrid?
I have been following papers, but I want a detailed description of the control and modeling.
Thank you
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Throughout the literature, the Curve Number (CN) has been identified as the most sensitive parameter in hydrological models. However, in my project, when I conducted a sensitivity analysis, the CN number did not show the expected level of sensitivity. What could be the reason for this occurrence? Thank you.
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A DNK is where a researcher makes a comment or asked a question with so many abbreviations that one simply Doesn't Know what s/he is talking about. Best wishes David Booth
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Hello, fellow researchers!
I am currently experiencing an issue while conducting structural equation modelling on Jamovi software. The software is displaying an error message stating that 'this analysis has been terminated, likely due to hitting a resource limit.' I am curious to know if anyone else has encountered this issue before and if so, how they addressed it?
Any insights or suggestions would be greatly appreciated. Thank you in advance for your help.
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Thanks for your valuable response. I'd try Laavan in R.
Warm regards,
Kolade
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I have thickness of nano membrane filter, pour size of membrane filter and initial & final concentration of wastewater.
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Very critical question I ever seen but interesting undoubtedly.
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Kindly suggest the names of the software used for Dynamic wastewater treatment modeling and energy analysis (for research purposes)?
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kLa is a very important design parameter for wastewater aeration. I have studied the energetic optimization and adaptive control of the dissolved oxygen concentration in aerobic fermenters by numerical simulation. The parameters of the usual KLa correlation were estimated on-line and at real-time through the recursive least squares algorithm with forgetting factor, most effectively when a small sinusoidal disturbance was imposed to the manipulated variables (stirring rate and/or air flow). The power dissipated by agitation was accessed by a torque meter (pilot plant). This investigation was reported at (MSc Thesis):
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Respected RG members
What are the pros and cons of modeling dynamics using psuedo- stochastic matrices as the transition matrix units?
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@ Amer Dababneh
Thank you for sharing the link.
Regards
D. Ghosh
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I would like to ask if anyone could write a procedure of the modelling process for a NSM CFRP strip including part type, section assignment, material type to choose, interaction with the epoxy adhesive and the model choices of the epoxy..?
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Hi, I have a small sample panel data consists of T=21 years and N=7 countries, with heterogenous slops and cross section dependence of my y and  most of my x's . I did the unit root test my variables are mixed stationary I(0) and I(1). What is the best modeling method? Thanks for your replies.
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Angelos Alamanos Thank you.
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I am working on the project involving nucleate boiling . I am trying to model the same in the ANSYS Fluent software. Can some one help me with the steps for modeling nucleate boiling in this case.
I would be very happy to have suggestions from you all. Thanks in advance.
Regards.
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Modeling nucleate boiling in ANSYS Fluent requires the following steps:
  1. Define the Problem Geometry: Create a 2D or 3D model of the boiling system you want to analyze, including all relevant physical boundaries and components.
  2. Choose the Appropriate Model: Select the appropriate model for boiling from the Fluent Model Library. For example, the models for boiling include, such as Homogeneous Model, Heterogeneous Model, or Interfacial Area Transport Model (IATM).
  3. Set the Initial and Boundary Conditions: Define the initial conditions, such as the fluid properties, temperature, and velocity, as well as the boundary conditions, such as the wall temperature and heat flux.
  4. Specify the Nucleation Site Density: In ANSYS Fluent, the nucleation site density can be specified using the Heterogeneous Model or the Interfacial Area Transport Model (IATM).
  5. Define the Material Properties: Define the material properties, such as density, viscosity, thermal conductivity, and surface tension, that are required for boiling simulation.
  6. Solve the Problem: Run the simulation in ANSYS Fluent and monitor the results, including the temperature profile, pressure, and velocity. You can also visualize the boiling process and analyze the results to understand the behavior of the system.
  7. Validate the Results: Validate the results against experimental data or theoretical predictions to ensure that the model is accurate and the simulation results are meaningful.
Note: The exact steps may vary depending on the specific requirements of your project, but the above steps should give you a good starting point for modeling nucleate boiling in ANSYS Fluent.
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Hi everyone,
I'd like to hear from anyone having advice on how to choose priors when modeling doing Bayesian stats using MCMCglmm or similar.
Any help would be great appreciated.
Thanks,
–PJ
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Do you mean which distribution to select? Or, how do I derive numbers to fill in for the parameters of my prior distribution? For the latter one the article below might be of help:
A search through literature might obtain values that can be used as prior information. Preferably people would give their estimations (point and interval), which harldy happens. If I fit i.e., y~B0+B1X1, I try to find figures, numbers or descriptive information from literature from which I can extract information on the parameters. Otherwise I also use personal data on the topic that floats somewhere around in my dropbox or github.
Best,
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Climate scientists have for over 20 years focused on emissions in their modeling of future scenarios of the global climate. These models, are based entirely on the level of greenhouse gases, particularly CO2, and include also the simulation of other factors such as El Nino and La Nina, the Great Conveyor belt, and ocean temperatures and the CO2 absorption by the oceans in the most advanced cases. Nevertheless, the modeling of future events is purely statistical.
However, the globe is undergoing dramatic changes in its core, and magnetosphere. First of all, the magnetic North Pole is drifting very fast away from the Canadian region and over to the Siberian region. It crossed recently the geological North Pole some years ago, and it is moving at an alarming speed of 8 meters pr day on its path. At the same time, the southern part of Africa is generating a massive anomaly on the magnetosphere which started exactly 160 years ago, coincidentally with the advent of the Industrial revolution and beginning of the massive emissions of CO2 from industry (1). At the same time, the Earth has started to spin faster around its axis, in fact so much faster that the clocks may have to be adjusted of some milliseconds. This is an increase in rotation speed of massive scale, considering the size of the planet, and it is attributed to the activity of the core of the planet (2).
40.000 years ago a similar dramatic event took place, where the climate changed very fast, and it may be connected to the arise of Homo Sapiens, and death of Neanderthals, by the rapid change in climate, the ability of the emerging Homo Sapiens to adapt to it, and perhaps, the effects the new climate had on the biological fitness of the new species to adapt to it.
In context with the multitude of changes that are occurring in the magnetosphere now in this period, and started to do so at the beginning of the increase in global CO2 emission, and the fact that we know it happened before, and generated changes in the atmosphere and also changes in climate gas composition, how is it possible that climatologists are solely basing their models on everything but the most widespread force of the planet, and also how is it possible that they don't include spin-effect of the globe on weather patterns (3)?
At the same time, there are very few studies on these aspects of the climate, and it seems they are also not popular in the realm of sources that are harvested by climatologists when they make their grim predictions.
Is the climatological field driven by bias and ignoring important physical phenomena on climate change?
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Hi Ross, this is a great question and I do not know the answer. Hopefully, someone here can answer this.
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Hello everybody, I am interested in catchment modelling and starting to read the research articles. However, I find it hard to conduct an experiment with GLUE estimate uncertainty in catchment modelling. Does anyone have a specific example that can help me with?
Thank you!
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Mohamed-Mourad Lafifi . Thank you for you answer, I am reading your suggestion!
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How to select bed material along with flow during the modeling of local scour around the bridge pier in ANSYS FLUENT?? Please provide some sources to tackle this issue.
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Thank you so much
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i have a problem with reaction modeling by Ansys Fluent. when i change the Arrenius parameters, nothing change and it makes me confuse. can anybody help me?
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n ANSYS Fluent, "Finite Rate" and "Eddy Rate" are two different models that can be used to model chemical reactions. The main difference between the two is the way they calculate the reaction rates.
Finite Rate: The finite rate model calculates the reaction rate based on the actual chemical reactions taking place in the fluid. It considers the chemical kinetics of the reactions and the local thermodynamic conditions. This model is more accurate but requires more computational resources and detailed information about the chemical reactions.
Eddy Rate: The eddy rate model calculates the reaction rate based on the mixing of the fluid. It assumes that the reactions are controlled by the mixing of the fluid and not by the actual chemical kinetics. This model is less accurate but requires less computational resources and detailed information about the chemical reactions.
Another difference between the two is that the finite rate model is more suited for high-temperature reactions, whereas the eddy rate model is more suited for low-temperature reactions.
In practice, the choice of which model to use depends on the specific situation. The finite rate model is generally used when more accurate results are needed, while the eddy rate model is used when computational resources are limited.
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I'm modeling a 4-point beam in ABAQUS, and I am wondering what the best way is to connect the reference points to supports (As shown in the picture below) is it a Rigid body (pin) or coupling?
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you can try to compare it and see the behavior after that. both are working well
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I am trying to assess the quantitative impact of climate change on hydrological regime of a semi-arid subbain; and I can not select among different customary models.
please help me based on your knowlege and experience in water resources modeling.
SWAT? SWAT+? WEAP? HEC-HMS? IHACRES? or something else?
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You can also check this page, brief description of different software and their abilities might help.
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I would like to get your opinion about which open source tool is more reliable for battery aging simulation and performance evaluation? There are various open source tools such as PyBaMM or OpenFOAM. I would like to get advice upon your experience.
Thank you in advance!
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Hi,
You also have BLAST and, for this, the Battery Software Open Source Landscape, BOLD, GT-AUTOLION...
For more information about this subject, I suggest you see the links on the topic.
Best regards
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there are six reactions that they are not linear or Arrhenius, so i need use some txt program to insert in app, but i don't know how? can anybody help me?
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Mohsen Najafi Non-Arrhenius reactions may be modeled in ANSYS Fluent by utilizing the "Reaction Rates and Temperature Dependence" model in the Reaction panel of the Species Model tab. Using a polynomial or a user-defined function, you may provide a temperature-dependent rate coefficient for your response.
Follow these steps to create a non-Arrhenius reaction in Fluent:
1. Select the "Reaction Rates and Temperature Dependence" option in the Reaction panel from the Species Model tab.
2. Enter the temperature-dependent rate coefficient for your reaction. A polynomial or a user-defined function can be used.
3. Indicate the temperature range in which the rate coefficient is valid.
4. Assign the proper reaction sequence and pre-exponential factor.
5. Set up the relevant reactant and product terms if your reaction includes several species.
6. Solve the issue normally, and the non-Arrhenius reaction will be accounted for in the calculations.
I hope this was helpful! Please let me know if you have any more queries.
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hello everyone I am modeling an impact problem via Abaqus. and my model consists of an impactor and a solid ball. The impactor impacts the ball through three different forces. and I extracted energy plots for all of these forces but I think they are not true because internal energy and kinetic energy didn't show an ending at the end of the plots. does anyone know if these plots are true or not and what should I do to have a better plot?
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Elahe Soheil Sarv It is conceivable that your model's internal and kinetic energy are not completely dispersed at the end of the simulation. This might be due to a variety of reasons, including the material qualities of the ball and the impactor, the model's boundary conditions, and the simulation's length.
You might attempt the following to increase the accuracy of your energy plots:
1. Check that the ball and impactor material characteristics are appropriately modeled in your simulation.
2. Examine the model's boundary conditions to check that they are properly defined and do not introduce any mistakes.
3. Increase the simulation time to allow for more thorough energy dissipation.
4. Consider using a more advanced modeling technique, such as explicit dynamic analysis, which can better capture high-energy impacts and accurately predict the resulting energy dissipation.
I hope this helps! Let me know if you have any further questions.
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In structured equation modeling, we use latent variables.
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Yes, we can. You are not required to model every variable as latent in an SEM. You can also include manifest (observed) variables such as age, gender, and income into the model (i.e., variables for which you do not have multiple indicators and/or for which you can safely assume that they are free or nearly free of measurement error).
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Hi
I am modeling the compression of a plate in honeycombs on abaqus, but I find problems concerning the latter, my objective is to compare the results found experimentally and numerically, for the experiment takes place in a duration of 150S, but this period is very long for modeling and I couldn't manage to use all of this period in the step part!
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I can help you
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Hi
I am trying to model a poro-hyperelastic material, but the problem is, this kind of physics is not present in any of the FEM software including COMSOL or ABAQUS,the comsol have a module only for poro-linear elasticity, but there are few papers on its modelling and they are using subroutine for that.
please help
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i finally did it in comsol using pde modules and i've used paper of selvadurai for the equations, and the convergence issue was tackled using changing the discretisation order and through hit and trial.
during porohyperelastic make sure u are defining correct value of the stress tensor matrix
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I am an undergraduate student doing a thesis regarding slope stability analysis using PLAXIS 2D. My study area is at Kajang, Malaysia. I only assumed the phreatic water level because I don't have any borehole data. I have already done the model but I have questions regarding my model:
1. Is the water level that I have marked and assumed logical? (40 m above flat land)
2. What does the legend on the right represent, and is it the FOS? (The FOS that I obtained from the model is 1.780 as shown in the picture below)
3. Is the part that I have marked in the picture the critical slip surface (Picture 3)?
Thank you in advance for your help.
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1. Im not sure if its logical, but as it is doesnt effect the stability slope much. If you predict it higher and repeat calculation, you could get much different results (less stable slope). So if you dont have any data and you want to play it safe, take into account higher level of water.
Questions 2 and 3 were already answered by others.
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I'm trying to solve a set of equations of motion of a system by ode45 in Matlab.
My phyisical memory is 24 GB. Matlab can use up to 100% of the memory but it only uses less than 50% of it and surprisingly I face an 'Out of memory' error!
What do you suggest as the cause of this problem?
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Thanks for your response.
It's already on the maximum limit.
In the new run of my code, I got these numbers for memory usage:
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Hello everyone, I'm trying to understand the nondimensionalization of the study "Modelling cholera transmission dynamics in the presence of limited resources" by Farai Nyabadza, Jennifer Mawunyo Aduamah1 and Josiah Mushanyu. I just wanna know how the substitutions were derived in order for them to nondimensionalize the model. Please see the pictures for your reference. Thank you in advance.
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Nondimensionalization is the partial or complete removal of physical dimensions from an equation involving physical quantities by a suitable substitution of variables. The paper you're referring to talks about the population movement in different classes with different dimensions concerning the total population. To make it simpler, the authors proportionalized the population into different classes with respect to the total population N. If you see the B, k, and b also depend on the infected population I and, therefore, need to be done.
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Hello everyone.
I have data with three outcomes (two is binary and one is continous with poisson distribution) and around 10 independent variables. My objective is search for factors predicting one main outcome and two secondary outcomes. I came across structural equation modeling (SEM) and it has very interesting concept. I want to ask that putting all variable to fit correlation in one SEM (with all three outcomes) equation is more suitable than separately putting variables in each regression equation (totally three equations)? (Actually, I have tried to analyze accordingly and found that some significant variables in logistic/ linear regression turned to non-significant in SEM.) I want to ask your opinion that technically and scientifically using only one model should be more suitable than three models especially in single study?
Thank you.
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You could examine all three outcome variables in a single model using path analysis. Having a single model (rather than a separate model for each outcome) is often preferable. You just need to make sure that you properly account for the scale level/distributions of your dependent variables. Some (but not all) programs for path analysis and SEM (e.g., Mplus) allow you to run path analysis for non-metrical (e.g., binary, ordinal, count etc.) variables.
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Dear all,
I am modeling PCM in heat transfer solids and fluids using COMSOL 5.6, but I am facing some problems with the solution in the initial time steps (within 20 seconds).
The domain temperature goes below the initial temperature of the domain.
I am using a time-dependent PARDISO solver and time-stepping BDF. I am attaching an image for your reference.
Your answer will be highly obliged.
Thanking you all
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These are what I would try:
1. Check your mesh size, change it and see if you still see the issue.
2. Use a higher order discretization for temperature (quadratic, etc).
3. In your results, look for the regions that are below the initial temperature. They are usually at the singular points (i.e. corners). If this is the case, try to refine the mesh in those regions.
4. Sometimes, the time step that the software selects automatically is not small enough. Try to set it manually and see if the issue is resolved.
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Historical data feed
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Thank you for answering @Omidali Najafi. In support of your answer, can you please refer any relevant literature, plzzz?
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Hello,
I'm undergraduate student in my final year. I'm stuck with my thesis on how to get pareto formula because in journal only have the final function not how to get it. I used Journal from EMEL KIZILOK KARA (A Study on Modeling of Lifetime with Right-Truncated Composite LognormalPareto Distribution: Actuarial Premium Calculations). Attached are my work so far. Sorry if my english is bad. Please help me to solve this.
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you can read this paper, I hope it will help you.
Deng, Min, Mostafa Aminzadeh, and Min Ji. 2021. Bayesian Predictive Analysis of Natural Disaster Losses. Risks 9: 12. https://doi.org/10.3390/risks9010012
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In rainfall-runoff modeling, it is often not possible to find the unique best parameter set, different parameter sets may be given similar good results during calibration. To reduce uncertainty and to define the optimum parameter set, it is a fundamental analysis of model parameters.
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Remote sensing, mapping, modeling, Disaster
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Nishu and others, thank you for your information.
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Hello everyone,
I need your help for the modeling of the alternator coil. i use lumped paramter model and distributed parameters model.
I would like to know how, t is what you do for the calculation of the different parameters; because I did it, I can't find results that agree with the laboratory tests.
Please can you help to have the good values of parameters?
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I would like to simulate a k-tier Hetnet or Self organized network (SON). Let’s say if k = 2, then we would have macro cells and small cells. UEs may connect to macro or small cells per certain mobility load balancing conditions. How can this be simulated in NetSim or in some other network simulator? Are there any good reference papers?
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NetSim computes the interferences as the sum of the received signal power from all interferers. That is from all BSs except the serving BS that operate in the same frequency as the serving BS. The received signal power would be transmitted power less pathloss. All BSs means in the same tier as well as in the other tiers, operating in the same frequency band.
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I am modeling an underground structure with fixed support conditions around the exterior walls. I would like to apply different ground acceleration time history data into specific nodes (joints) of the structure. Is this possible in SAP 2000? I would appreciate any guidelines. Thank you very much!
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Hi Woongchan,
Yes, it is possible!
However, you need to convert the acceleration records into displacement records using SAP or any other seismic software. Then you define load pattern for each loading record and assign a unital displacement load on that node using the defined load pattern. Finally, define time history load case for using load pattern not acceleration. You may check Appendix B in my thesis on how to conduct multi-support excitation time history analysis using SAP2000.
Best,
Bashar
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Can Big Data Analytics technology be helpful in forecasting complex multi-faceted climate, natural, social, economic, pandemic, etc. processes?
Industry 4.0 technologies, including Big Data Analytics technology, are used in multi-criteria processing, analyzing large data sets. The technological advances taking place in the field of ICT information technology make it possible to apply analytics carried out on large sets of data on various aspects of the activities of companies, enterprises and institutions operating in different sectors and branches of the economy.
Before the development of ICT information technologies, IT tools, personal computers, etc. in the second half of the 20th century as part of the 3rd technological revolution, computerized, partially automated processing of large data sets was very difficult or impossible. As a result, building multi-criteria, multi-article, big data and information models of complex structures, simulation models, forecasting models was limited or impossible. However, the technological advances made in the current fourth technological revolution and the development of Industry 4.0 technology have changed a lot in this regard. More and more companies and enterprises are building computerized systems that allow the creation of multi-criteria simulation models within the framework of so-called digital twins, which can present, for example, computerized models that present the operation of economic processes, production processes, which are counterparts of the real processes taking place in the enterprise. An additional advantage of this type of solution is the ability to create simulations and study the changes of processes fictitiously realized in the model after the application of certain impact factors and/or activation, materialization of certain categories of risks. When large sets of historical quantitative data presenting changes in specific factors over time are added to the built multi-criteria simulation models within the framework of digital twins, it is possible to create complex multi-criteria forecasting models presenting potential scenarios for the development of specific processes in the future. Complex multi-criteria processes for which such forecasting models based on computerized digital twins can be built include climatic, natural, social, economic, pandemic, etc. processes, which can be analyzed as the environment of operating specific companies, enterprises and institutions.
In view of the above, I address the following question to the esteemed community of researchers and scientists:
In forecasting complex multi-faceted climate, natural, social, economic, pandemic, etc. processes, can Big Data Analytics technology be helpful?
What is your opinion on this issue?
Please answer,
I invite everyone to join the discussion,
Thank you very much,
Best wishes,
Dariusz Prokopowicz
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Dear Dariusz
The simple answer is YES!
The problem, however, is that the analytics are imperfect...
It is necessary to understand how human intuition (expert intuition) works... I am convinced that understanding the mechanisms of intuition holds great potential for improving analytics and forecasting...
My own research shows that nature has found genius ways to deal with radical uncertainty with limited resources...
Yurii
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Dear All
I am trying to simulate the bond behavior between concrete beam and CFRP using ABAQUS.
I tried different ways to do so, but no one works. I got the following errors as in the attached pictures.
Thanks
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The soil properties such as soil pH, moisture, temperature, NPK, Carbon content, texture, etc forms important parameters for the growth and distribution of a plant. And for distribution modelling of a species, the raster dataset is required. How can I acquire that?
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in the flexural 3PB test, a concentrated displacement load would be applied to the top middle point of a beam. For modeling one-half of the beam using symmetry, which nodes or edges do you think should the roller and load point be assigned to avoid coincident of the BCs and errors relating to stress concentration in a nodal load point (after meshing, image attached)? is it not a better idea to assign the displacement load directly to the whole side edge using these BCs ( U1=0, U2=Value, U3=0, UR1=0, UR2=0, UR3=0)?
any idea would be appreciated.
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dear
Claudio Pedrazzi
thank you for your answer,
all these tricks are done for simplifying the model and to keep the number of surface contacts as low as possible (there are plenty in my case), also the exact E-Modules of the roller of the machine is not available.
As you said, applying the symmetry conditions to the side edge and the load to the top node may work.
your answer helped...
I will be following other ideas on this issue
God bless
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Dear Researchers,
As you know, it is possible to generate the code of modeling in SpaceClaim and FE analysis in Ansys. However, I do not know how can I connect the codes of these sections.
I Ansys Apdl, it can be generated completely but I do not know how can I do it in Ansys workbench.
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Thank you for spending time and responding to my question. I will read and watch your references. That would be helpful for keeping on my research.
Regards
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In majority of current literatures, the two words are used interchangeably. Although some works distinguish the semantic difference between them (Tumeo, Mark. 1994. “The Meaning of Stochasticity, Randomness and Uncertainty in Environmental Modeling.” In , 10/4:33–38.), the difference in the detailed modeling techniques is still unclear.
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Various technical (mathematical) modeling methods (techniques - if you wish) do not really follow semantic differences in "uncertainty vs. stochasticity", that is, it should be better to dig-in into the specific modeling approaches (techniques) on a case -by-case basis.
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Is alphafold able to incorporarte ptm data ?
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Thank you
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How can we calculate the number of dimensions in a discrete space if we only have a complete scheme of all its points and possible transitions between them (or data about the adjacency of points)? Such a scheme can be very confusing and far from the clear two- or three-dimensional space we know. We can observe it, but it is stochastic and there are no regularities, fractals or the like in its organization. We only have access to an array of points and transitions between them.
Such computations can be resource-intensive, so I am especially looking for algorithms that can quickly approximate the dimensionality of the space based on the available data about the points of the space and their adjacencies.
I would be glad if you could help me navigate in dimensions of spaces in my computer model :-)
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Anil Kumar Jain The description of discrete spaces is found in physical works, e.g. "Discrete spacetime, quantum walks and relativistic wave equations" by Leonard Mlodinow and Todd A. Brun, https://arxiv.org/abs/1802.03910. But I have not seen any attempt to quantify the dimensionality of such spaces. This is exactly what I am looking for.
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Applying mathematical knowledge in research models: This question has been in my mind for a long time. Can advance mathematics and applied mathematics solve all the problems in modeling research? Especially the formula derivation in the theoretical model part, can the analysis conclusion be obtained through multiple derivations or other methods? You have also read some mathematics-related publications yourself, and you have to admire the mystery of mathematics.
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Nobel Laureate Eugene Wigner once said
"The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve."
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I am having difficulty in modeling interface in VASP so that I can relax it.
I could not find an example of inputs for modeling interface.
If anybody can check my inputs in the attachments or guide me in any other way, I would appreciate it.
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Hi,
Two things:
1. you need make a common unit cell with equal lattice parameters. In your case you have 3.98 for Pt and 4.15 for Ag. So, you either have to compress Ag until cell to 3.98 or you expand Pt unit cell to 4.15, this way you can put both the Pt and Ag in one common unit cell.
2. After you create individual cells, you can put them back on top of each other using VESTA software.
I think this explanation is bit Raw, you will a bit more details. You can look into this video on Youtube, link below:
I hope this helps!
Thanks,
Khagesh
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Which of the following is the best for estimating phonon contribution: a non-magnetic analogue or Debye-Einstein model?
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I think Debye-Einstien model is good for estimation.
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Hi!, I'm currently on a investigation project that consist in production of charcoal by slow pyrolysis of wood. As we know, the products of this process is char, syngas and tar. The thing is that we want to minimize this tar production because its complicated usage. For what we saw, the tar can be degraded to volatile non-condensable gases and avoid that liquid phase. The temperature we are modeling the process is about 400-450 ºC,. My question is: is this enough to only have coal and syngas at the end of te process?. If not, how can we avoid the tar production and only have syngas as byproduct? I hope I have explained myself well.
Thanks!
📷
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You will always make "tars", i.e. condensable organics, from biomass pyrolysis. Either burn the raw syngas for heat, which is the easiest option. if you want to turn the tars to syngas, do not use catalysts - you need to use superheated steam or superheated steam and a little O2 to reduce the tars to syngas. 800°C to yield a pretty clean syngas. Did this 17 years ago. Then you can pass the hot products over an Ni catalyst bed (preheated) to remove trace organic compounds from the gas.
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I am working on modeling of Direct Contact Membrane Distillation system with COMSOL Multiphysics software. I have some problems with the mass transfer part of the simulation because I don't know which boundary condition is appropriate for boundaries between membrane-cold and membrane-hot channels. Is anybody knows how I can solve this problem?
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When modelling the softening behavior of quasi-brittle materials as concrete, mesh sensitivity is very important unless we use a regularization technique. In tension there are many available in the literature, but what are the techniques available for compression?
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Not quite, but thank you for your answer
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I have a query :
I had written a paper few months ago and its prepreint is floating online.
Query: I want to add more additional results along with modeling in that paper and submit it to some other journal. Can I do the same because a preprint is already floating online? Won't it count in the plagiarism count by the detector? I mean I know preprint is also my earlier version of the same paper but software dont.
Kindly help me with this.
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Dear Prof. Amit Das,
Preprints are defined as an author’s version of a research manuscript prior to formal peer review at a journal, which is deposited on a public server. ResearchGate (RG) said about "Preprints": "early-stage research" and "Draft paper before peer review".
On the other side, RG is not a publisher and, in turn, uploaded unpublished text is not regarded as a publication. Hence, a preprint is an author's own original or draft version of their paper before any peer review has taken place and before it is published. As soon as it's posted, a preprint becomes a permanent part of the scientific record and, in turn, it can be citable with its own unique DOI.
Now, before answering this valuable question of Prof. Aijaz Panhwar, please let me give my own opinion about the preprint dilemma (مُعضلة ما قبل الطباعة):
I have a different perspective on uploading any preprint anywhere before it has been published. Why do you let others know about your insights and methodologies before publication? You should avoid telling the other researchers about the details of any one of your papers until it has been published and seeing your name by yourself. You may say that I am somewhat old-fashioned, but I have a different perspective on uploading any preprint anywhere before it has been published by your name. My advice is not to put your research anywhere until it is published. It is a security issue:
  • Your manuscript may be copied and then published by others before you can do that. This stealing of your paper might be happening. So, you must wait until the paper is accepted and then published in that journal. Then, upload that research item on any platform you wish.
  • You should avoid telling the other researchers about the details of any one of your papers until it has been published and you are seeing your name by yourself.
  • A journal may have automated plagiarism software to check the paper before admitting it to the reviewing process. There are chances that your paper can get a rejection at any point. Thus, to avoid this problem. Publish the preprint after you got the paper as "ACCEPTED".
  • There may be a "cold war" between the professors of a given department. They do not like to discuss ideas as others will "steal" them and publish an article on them without giving credit to the one from whom they got the idea. My suggestion is to keep your work "private" and share it only with those who are really interested.
  • Academic publishing remains a competitive process. If someone else has recently published a paper very similar to mine, mine is less likely to be accepted. So although I may share my topic, I prefer to keep my methodology, findings, and discussion private, until published in a peer-reviewed journal. So, there is a high chance that someone may claim your idea as theirs!
  • Preprint gives a false feeling of security. Personally, I would always wait until the paper is accepted by the editor of a journal. After that, I can post it as a regular research item on any platform you wish.
  • A reminder for all respected researchers: Don't put any research, including preprint, anywhere until you are certain that it is published and tagged with your name. The information presented in the preprint is potentially available to be stolen and republished. There is also a chance that someone may plagiarize your paper!
Finally, for the coming future, do not upload any paper anywhere until it is published with your name. Even if it is a "preprint"! For the time being, If you had done something like that as a "preprint", for instance, I advise you to delete the preprint from any elsewhere and wait for two months before sending the paper to any journal.
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Actually I am new in this field. Also this research topic is readily new. So, I need a preferable software to work with this topic. I can't progress my work without any reliable software
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You can also use SCAPS software for modelling.
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Hello, I am looking for documentation related to the WinITDB model for tsunami simulation, I have not been able to find results on the web. I hope to have your help, thank you.
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Hello,
Here are more links that might help you to figure out with WinITDB model:
- http://tsun.sscc.ru/PDM.htm (this contains some useful information)
Good luck!
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I am working on modeling coronal discharge formation and electric breakdown in a non-uniform electric field with air as an increasing velocity medium. I can find plenty of tutorials and articles about electric breakdown in air, and transformer oil, but none of them are moving. I am using COMSOL.
Modeling how coronal discharge onset and breakdown voltages change as a function of air velocity moving through the cylinder between electrodes is the question. To be honest, it seems more straightforward and useful to set up the experiment and get empirical data since we need to know this for the next steps of research. However, worth asking.
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How do I scale and translate the model, OR how can I adjust the dynamic range to accommodate my model size. I have this problem when trying to simulate an antenna in CST in micros. Anyone, to assist?
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Use metres instead om mm, so the numbers are not so big (scale), or move the model to near the origin so that the numbers are as small as possible (translate), or both.
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Agent-based modelling (ABM) is a widely used modelling approach in different areas.
By allowing the simulation of several heterogeneous "agents" and their interactions, the ABM approach has been used in a lot of research.
In this question, I am trying to conclude the application of ABM in different disciplines, and conclude why these researchers use it.
I ask the same question in Zhihu(知乎)
多主体建模(ABM)可以用在什么课题的研究上? - 知乎 https://www.zhihu.com/question/551001659
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I was involved in developing agent based models used to test possible management strategies for controlling the impact of human activities and use in regional ecosystems. Testing such management models in real life is difficult since actual trials are likely to perturb "the base-line" required for meaningful comparison.
These sorts of models are especially important in systems which involve vulnerable populations exposed to biased risks (such as "trophy fishing") that impinge on reproductive capacity.
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Hi,
I am looking at the three-way interaction of a latent variable (F) with ordered-categorical indicators (mostly likert scales) and two observed variables (M1, M2), using Mplus. The two following issues arise:
1. How do I account for the ordered structure of the indicators? Do they need to be defined as categorical?
2. What does this mean for the standardization of the latent construct (F)? Standardizing the indicators does not seem appropriate!
Any advice or guidance is greatly appreciated. Thank you in advance!
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Joanna, Mplus now provides the option to use cat-LMS. Therefore, you just have to define the indicator variables as being categorical, and then the usual syntax of LMS can be used.
HTH, Karin
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Is there is any differences between modeling using Mplus and HLM
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Hello Asma,
HLM (hierarchical linear models), otherwise known as multi-level models, represent one kind of model which Mplus can be used to analyze. The program is capable of much more than that, however, including SEM, IRT, and more. There are many other software packages capable of handling multi-level models, several of which are free, such as:
It's sort of like asking, is correlation different than SAS / SPSS / Stata / Jamovi? These (SAS et al.) are software packages which offer correlation analysis, along with a host of other analytic options.
Good luck with your work.
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Hello:),
for the above inquiry which software is most accurate/easy to implement?
Thanks:)
Joel 💡
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I checked your file using Pymol, see the attachment, please.
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If I have a protein sequence without any structural information. Can I determine the oligomer forming capacity of the molecule after modelling? Are there any tools or calculations to determine this as well?
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Experimentally, you would check for oligomerization by comparing the theoretical size of your protein derived from the sequence to the apparent molecular weight of the protein determined by gel filtration and light scattering. If you are dealing with an enzyme or receptor, the Hill coefficient can indicate cooperatively between the ligand or substrate binding sites https://en.wikipedia.org/wiki/Hill_equation_(biochemistry)
Check what is already known and published about your protein and its orthologs in other species. Consult the information for your protein on UniProt https://www.uniprot.org for a summary.
Then search for the closest homologs in the PDB database https://www.rcsb.org - what is their oligomerization state? This is an integral part of modelling the structure of your protein. Do a template search on SwissModel https://swissmodel.expasy.org - This will give you a list of related proteins and potential templates with links to their info on the PDB and Uniprot records
Comparison of the structures of related oligomeric proteins to the sequence conservation between the orthologs of your protein in different species may help to determine whether oligomer interface residues are more conserved than surface residues outside the interface, suggesting that the structural interaction is conserved.
If you have found that related proteins in the pdb are oligomers, you can use these as templates to build the oligomer of your protein. Without such information, you can use symmetry docking to explore potential interactions: http://bioinfo3d.cs.tau.ac.il/SymmDock/
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I want to model a plate spring model in comsol , a type of model attached with this discussion.
How can I model this type of geometry ?
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Sorry , this is out of my faield
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Hello dear all,
We want to set-up a CFD -Discrete Particle Modelling case for a bubble column where liquid is eulerian and gas bubbles and solid particles are discrete phases (three-phases total holdup <10 %) as given in attached diagram. In this case only gas bubbles are flowing with velocity UG <1 cm/s while liquid and solid particles have no initial velocity (means batch mode). Boundary condition (DPM) for gas phase at outlet is pretty straight forward "escape" but we want to retain second discrete phase "particles" with in column volume. However, Boundary condition panel in Ansys Fluent do not show "escape" or "wall" or "reflect" for an individual DPM (injection) phase but one for all DPMs.
We want to model the effect of gas bubble induced flow behavior (in one-way coupling) on liquid and solid phases, so we need to keep liquid in batch mode and solid phase (one-time injection). Any suggestion on how to set-up DPM-BC for two discrete phases (two different injections) separately in Ansys Fluent?
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Hello Tyagi,
I am not sure it is possible to use DPM in a three phase flow situation with Fluent but I am not an expert in DPM. Meanwhile, I suggest to simulation the gas-liquid flow with the Euler-Euler model and the particles with the DPM, I hope it should work better when gas hold-up is greater than 5%.
Best regards
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When I was a Student, I used to find the modelings of mechanical systems unclear. The problem of students is that they can't find easilly the suitable modellings for their studies.
Hence, I am inviting mechanical engineering Professors to be volunteers in a New Project that gathers very simple and clear modelings of all the mechanical systems that students may encounter in their high Studies. The Project will obviously need endorsers of mechanical engineering in order to make the gathered works available even in Arxiv community.
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Hello,
I am working on growth in an avian species. The model that fits the best on my data is the Morgan-Mercer-Flodin (MMF) model. I am surprised to note that this model is compared with others so rarely in the majority of the studies, rather than Gompertz, Logistic, Richards or Von Bertalanffy models. I tried to understand why but I was unable to find a reason.
Would someone have an idea about this issue?
Thanks a lot.
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Hi, I don't know if you still need an answer, but you made me curious about this model. Could you share some real data, so I can implement it in my software and experiment with it? Of course I'll inform you about my findings.
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Hello,
I have credit risk/default data for probability of default modeling. Indeed I need to give credit score each costumer. As I know, initially I should model scores and then calibrate it into PDs.
Can you share me some materials/literature about how to estimate/calculate credit scores?
Thanks
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Chapter 1 of this book
<Löffler, Gunter, and Peter N. Posch. Credit risk modeling using Excel and VBA. John Wiley & Sons, 2011>
gives a useful description of how to deploy logistic regression for scoring scoring.
If you want the full picture have a look at
<Anderson, Raymond. The credit scoring toolkit: theory and practice for retail credit risk management and decision automation. Oxford University Press, 2007>
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Hello everyone,
I am modeling an RC bridge pier under constant axial and cyclic load in ABAQUS software. The concrete is modeled with the CDP model. The step analysis is used as Dynamic implicit Quasi-static.
The result of the hysteresis curve is different from the experimental result as shown in the figure. I tried several methods but could not get the desired result.
Any recommendation on why the results are not matching?
Thank you.
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Hello
That is an interesting observation. I work in theoretical aspects of mechanics, since don't work directly on concrete or Abaqus, my reply will me more fundamental (may not be helpful to you at all:
I can observe the following from the image:
1) Initial modulus of the exp is less than the numerical (issue of material constants)
2) More interesting observation is where all the loops of numerical are fairly regular (just scaled up size), the loops of exp are tilting clockwise. This meas the material is becoming softer cycle after cycles. One possibility is the real sample has some homogeneity (such as voids) which are growing with evey cylce and making the response softer.
3) Lastly, the numerical plots are flatter at higher strains, which happens when the chosen constitutive relation reaches saturation (slope=0, or perfectly plastic). Since the real sample doesn't show any evidence of that, you may need to check the yield criteria and post yield constitutive law
I know I haven't given the direct answer to your question. I hope above helps you to reach the solution faster
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I was trying to model a system with several chlorophyll molecules and carotenoids. For adding hydrogens, I used chimera which is working perfectly well for carotenoids. However, the chlorophyll molecules are not getting pronated in the desired manner. There are discrepancies in the number of hydrogen atoms. Sometimes, these packages fails to identify the valencies correctly. The results were even worse when Pymol is used. Previously, I used HAAD for this purpose. Unfortunately, HAAD is not giving any outputs this time (only getting 0 KB files). I need to add hydrogens to these molecules before setting up a system in GROMACS. How can I model these chlorophyll molecules accurately?
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Hello
For adding hydrogen you can use [Avogadro] advanced molecule editor https://avogadro.cc
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I'm studying about this issue and would like to modelling it in Econometrics moreover modelling it with various Energy Modeling.
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You need to take enough data (time period) before and after tax cuts. A good econometric model based on time series or panel data will suffice.
You can have a look at gravity model of trade.