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# System Modeling - Science topic

Explore the latest questions and answers in System Modeling, and find System Modeling experts.

Questions related to System Modeling

User mode and Kernel-mode are two processing statuses of the operating system. Please suggest to me, a very simple example in which you can explain the differences and other functionality such as system calls, interrupt to a novice learner.

Further, just inform how to map the example with subject

^{Disclaimer}_{The discussion targets the perspectives of two types of participants.}

_{Operating System subject's Student: please analyse the functionalities and construct an answer.}_{Computing professionals/teachers: please use your experience and insert answers as advice.}

_{It is warmly welcome the ideas of both the groups as well as interest audience}

1. I have designed a PV system that is expected to generate 1.5MW power but all get is 0.8MW what could be the problem? the model has a buck convert and an MPPT P & O algorithm and a three stage charge controller and how do you determine the arrays measurement filter time?

2. how do you size a buck converter and what should be the constant charge voltage of a 48V battery?

3. what is duty cycle and its relationship to the power, and what should be the MMPT step size of the model?

4. With a model that generates this amount of power how do you decide its system voltage and the switch frequency?

I want to build system model consist of IoT devices, mobile edge computing servers, cloud

and I want to sending multiple random request from IoT devices , and work some algorithm on the mobile, what is the best simulation i can work with it

Hi all,

I'm looking for PFT time series (global scale preferred). I found OSS2015 PFT (PHYSAT) in hermes but I wonder is there any other open database of global PFT to compare with earth system model prediction?

Best,

Hyung-Gyu

How is it doable the implementation of STS(socio technical system) approach based on SSM (soft system methodology)? Or in conjunction with? Since both are definitely separate concepts or approaches!

I want merge them to "design a conceptual system model".

I am referring to prospective REGIONAL (NUTS2 or NUTS3) approaches, using modelling frameworks (TIMES, LEAP, OSEMOSYS, ENERGYPLAN, MESSAGE, etc.), with simulation/optimisation procedure, scenario analysis, 2030-2050 or more, etc.

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.

Dear collegues,

I am doing a system modeling by software and I am not sure how to introduce the system and validate the results of the system.

I would like that somebody could conctact me to solve this doubt.

Thank you so much!!

Dear Colleagues!

If you are interest to develop your knowledge in Environmental and Chemical Engineering Modelling so you are welcome to apply for this distance (100% online) course at Mälardalen University (MDU)/Sweden where you will meet experience teachers in this field. More information about this course can be found on this site:

Best Regards

Yahya

How can we differentiate the terms "prediction" and "forecasting" in system modelling?

I want to improve the driving performance of a track robot such as pacbot...

I want to use IMU to measure directions, control the driving force of the robot to make it work in a straight or curve, and to work without slip.

So I need information about system modeling of a track robot. like (Mq''+cq'+g=F)

Do you have data such as linearized simple models or complex nonlinear models?

I would like to try to use matlab.

If you have any data you have, please be shared?

thank you.

Hi,

I am trying to create a full system state space model for an inverter.

References:

Conference Paper State-space model of an inverter-based micro-grid

Both papers have modelled individual controllers and then combined them to create a full system model.

Both have used the same technique, does anyone have any literature on how they came up with a complete system model, that combines all the state space models into one big one?

Regards,

Sandford

#PSCAD

Does anyone have a readily available IEEE 34 bus distribution system model in PSCAD?

Hello,

please i need help from expert with sliding mode control, actually I am confused a bit between 2 things.

i know that the supertwisting sliding mode control law contains two terms u = uequ + ucorr, the uequ is the one that depends on the system model, and the ucorr is correction control law that does not depend on the system and sometimes we can neglet the uequ term for more robustness. my question is if we neglet the uequ term the sliding mode control will be called model free sliding mode control ? or the model-free sliding mode control is something else ? because i read that the model free sliding mode control depends on the state measurements and on the previous control input (so it seams for me that it differs than just excluding the equivalent term in the supertwisting sliding mode..) and at the same time i read i many article defining the model free smc that it depends only on the state measurements and on control input and not on the system model and so that is why it is called a free model control.. so i am confused now what is the difference between them ?

thank you in advance

According to the nature of temporal data, strategies like k-fold cross validation is not an appropriate idea since we cannot remove the dimension of time. In this discussion we want to explore ideas about testing models for temporal data.

A good number of software available in the market for simulation and modeling of manufacturing systems. Users are lttle bit confusd to use whih software is best,

I have been working on Mathematical modeling, design and Simulations of clarifier systems for wastewater treatment. The clarifiers is envisaged to handle 40000litres capacity of wastewater at a time. Which of Circular or Rectangular clarifier modeling and designs will you recommend to handle Industrial wastewater?

I want to make a Circular Manufacturing System model for an Industry focusing on Resource Conservation, Product's multiple Life cycle, and value recovery options. I want to make a continuous state simulation approach by using Systems Dynamics Principles. Can anyone give some insight that it is possible to incorporate BlockChain Technology by any way in that context?

Thanks in advance. Best regards

Riad

Hi,

i want to classifiy time series of varying length to classify drivers of a bike by the Torque. I was planning on dividing the signal in lengths of lets say 5 rotations so the length of the time series would vary by the velocity of rotation. Do I need to extract features like Mean value and fft or is it enough to simply apply the filtered signal to the classifier?

Thanks in advance

Optimization of hydrocarbon pipeline transportation and allocation using a pipeline network measurement system model

I am doing a project with PV array in Simulink. When I run small section of the total system i do not get an error. But when i integrate full system(my system model`s are completely okay) I get an algebraic error saying

"An error occurred while running the simulation and the simulation was terminated

Caused by:

Simulink cannot solve the algebraic loop containing 'system_approach_first/PV Array/Diode Rsh/Product5' at time 0.0 using the TrustRegion-based algorithm due to one of the following reasons: the model is ill-defined i.e., the system equations do not have a solution; or the nonlinear equation solver failed to converge due to numerical issues."

Can anyone say me the route to solve this irritating problem?

I have made simulation sample time very small but the problem still on. Also i reduced tolerance to a very small amount

I have made a system model which is running well in Matlab/Simulink. When same system is implemented using Typhoon Hil software, it is compiled successfully but, showing NaN value (and value is replaced by zero) while capturing the response. Can you suggest me any solution?

I am trying to model a system which consists of a second order linear part (for example a set of mass spring damper with variable parameters for spring and damper) and a non-linear part which is a cascade of a derivative, a time delay, a static non-linearity (e.g. half-wave rectifier) and a low-pass system. I want to use neural networks for this purpose. I have tried time delay neural networks which were not successful. I am now trying to use RNNs (Recurrent Neural Networks). Since I am relatively new to this subject, I was wondering which network architecture are suitable for this purpose? (I have to use a limited number of parameters)

I am a PhD student interested in stochastic predictive control. As a first approach, I am working in the implementation of this strategy for uncertain linear systems with bounded disturbances. I have read conference and journal articles, but I still have doubts about its classic implementation (system model, cost function, prediction model, constraints, etc). Could any of you please suggest me a "key" reference or references about this topic? I am looking for some documentation as a theoretical foundation. The sort of models I am working with are

X(k+1)=A(gamma)*X(k)+B(gamma)*U(k)+D(gamma)*w

Thank you in advance

Dear All

There is 1-DOF Series Elastic Actuator(the scheme and state equation is given in the image). A=[0 1; -K/m 0] B= [0 -1/m]*F

where K is the stifness constant of the spring, m is the mass of joint, x is the distance, done by spring.

Could you give me the suggestions on how to write the controller, which gives proper value of spring constant(K) according to the desired(reference) distance, which must be passed by spring. It is necessary to highlight that the control input force is constant and distance can be controlled only by modifying the value of spring constant.

My previous idea was to apply adaptive MPC controller(with Kalman Filter or System Identification).

But the problem is that the value of stiffness constant, is located in "A" matrix, and it must be treated as "INPUT" variable, and not as variable with disturbance or nonlinear one.

P.S. It also didn't work with Linear Function.

Thank You in advance.

In the last years, I have been observing a growing trend of publications on long-term city/urban energy planning based on energy scenario assessment and making use of simulation and/or optimisation modelling tools such as LEAP, MARKAL/TIMES, or even ad hoc created energy models to evaluate different visions of the sectors and specific technology penetrations. In Europe, for instance, results from the FP7-INSMART project seem very interesting (https://cordis.europa.eu/project/rcn/186975/en).

Opinions? Ideas? Approaches?

Regards

I need transfer function for the mathematical model of solute and fluid transport in human kidney for the simulation purpose.

Hello, Dear Researchers,

I work on data-driven control algorithm design. So, in this case, we do not have any information about system model, but we have input-ouput (I/O) data collected. Based on I/O data we want to get estimated value for system matrices, in case we will obtain the estimated values of the matrices, should they be almost close to the system matrices of a known model (i.e. system matrices are found from model-based case)? Your answers will be valuable for me. Thanks!

Autonomous System modelling

I am trying to model a MIMO system with several variables. In this, how can identify significant variables to avoid complex system model?

Dear colleagues,

I've been researching on the application of machine learning techniques to improve the performance of complex communications systems. The main reason of using machine learning in those systems is because it is difficult to find a closed-form function that models their behavior and, therefore, optimize them.

However, in the past days I've been thinking about whether there would be a way to learn the transfer function of a system (even if it is non-linear) from the data of its inputs and outputs. Any thoughts regarding this idea?

Thanks in advance for your interesting and helpful comments.

We are going to design a path tracking controller with switched model discretization methods in MPC frame. To address this problem, short time steps t1 are used initially to accurately model vehicle stability and longer time steps t2 are used later in the prediction horizon to efficiently extend the preview length.
However, it shown "

**Output returned by S-function ‘MPC_11’ in ‘Controller/S-Function’ during flag=3 call must be a real vector of length 10**" when use Matlab to make a simulation.I initially think that it is caused by the negative infinity of the prediction matrix. But I do not know how solve it.

I am looking at a topic related to transportation modeling

What's new in the learning algorithms for the T-S fuzzy models?

when you build a T-S fuzzy model, you need to develop new learning algorithms for updating the parameters of the model. the updating term must be stable. Suggest to me new algorithms for the learning process.

I am working on a project where we are going to develop controller for batch fed biomass boiler.We have done some experiments in our lab setup and those experiments are time consuming.I want to know whether

there are software packages which we can model and simulate the biomass combustion and as well as the control system modelling.

I want know about both commercial and opensource software packages

In

**Sugeno Fuzzy Inference System Model**Output membership function is either linear or constant in the following form z = ax + by + c

Here a, b and c are different for each rule ( as per my understanding)

Now how to find the

**a, b, c values**for each rule, manually or with any algorithm ( not from Matlab) ?How to calculate the sum and the subtraction of many random variables that follow exponential distributions and have different parameters ?

(The value of Lambda is different for all or some variables).

example :

L(t) = f(t) + g(t) - h(t)

with

f(t) = a.expo(-a.t)

g(t) = b.expo(-b.t)

h(t) = c.expo(-c.t)

st:

a = Lambda_1

b = Lambda_2

c = Lambda_3.

Hi, I am working on a PV system model with battery and I need your expertise on an issue. When I check the power value of my pv panel with constant irradiance and battery, the power values for both of them are fluctuating. I check the output from the charging and discharging terminal, it seems that it is charging and discharging at the same time, would this be the cause for power flucuation? Would the PWM generator cause the PV panel's power output to fluctuate?

Good evening all,

I have started working with pneumatic muscles very recently. I do not have much knowledge in this area for which I need your expert opinion and guidance. Please suggest me the way out to start from the beginning towards controlling the actuation and developing the mathematical model of the actuator.

With regards,

Bhaskar Ghosh

HI, Just moved and set our extracellular field recording rig in a different (older) building. My goodness, I have so much noise! I have attached grounding wires to all components (chamber bath, interface chamber, each headstage) and the noise is beyond terrible. I am using new chemicals, same type of medical grade 95% O2/5% CO2 that I used in my old building, same faraday cage, same headstages and electronics...

I'm wondering if I really have not "grounded" my devices properly? I was always taught to install a metal screw into my anti-vibration table base and attached ground wires there. Should it be something else? That is what I did at my old building and even though we sometimes had noise issues, it's nothing like this.

I've attached a picture of what my experiment looked like.

For reference: Using Axon CNS 1440A Digidata, AM-Systems 1800 Amplifiers and headstages, AM Systems model 2200 Stimulus Isolators, Formvar-coated Nichrome wires for stimulating electrodes...

Hi guys !

I have a fundamental question regarding the fitness criterion when performing a model estimation for system identification. This far, I have obtained a good model for a driving simulator identification task. In this post, I want to discuss the SISO vertical model. The training data has been obtained by an acceleration sensor which delivers the vertical acceleration signal. Measurements have been performed in a frequency range of 0.2-20Hz. It is obvious that for small frequencies the sensor noise is considerable.

After estimating the (nonlinear) system models, I have calculated the goodnessOfFit using the NRMSE and NMSE focus. I have found that the NMSE yields significantly better fit results compared to the NRMSE. I have understood that the NRMSE is the better choice for describing a 1:1 fit, either the model fits perfectly or it doesn't. However, the NMSE seems to punish outliners less harsh than the NRMSE does.

Thus, I want to argument that my model is good based upon a NMSE measure. The reason being is that for the lower frequency parts the identified model is robust against noise and does not model it. Therefore, it is obvious that the model will not represent the noise in the training signal and is better described by a NMSE criterion than a NRMSE one.

The bigger plot (lolimot_noise_training.jpg) shows what i mean. Training was done using a local linear model approach with a concatenation of single sines as training data. The model was cross-validated using sweep and noise test signals.

The original training signal (unzoomed) can be found in the second plot (copy.jpg).

To put the plot in numbers:

Fit using NRMSE for the training signal : 87%

Fit using NMSE for the training signal : 98%

Similar values for the test/cross-validation signals.

So my final question is: What do you think of this argumentation. From the plot it is clear that the obtained model is sufficient and good enough to fully represent the system dynamics. I would like to pursue my argumentation using the NMSE as a measure of fit instead using the NRMSE. Though, I have found that in most literature the NRMSE was used most often, however being performed on more 'clinical' training data without too much of a noise.

Thank you very much !

I am looking forward to work on System Modeling and Control theory in Power generation, Aerospace or in Robotics. This is a completely new field for me and i need to do a lot to build the foundation stronger to carry out innovative research. Currently, i am reading books to understand relevant concepts as well as i am reading latest research papers to be familiar with new research in the field. Unfortunately, i am still clueless about this new field.

I need some expert advises from experts in this field that how can i master the concepts and bring the concepts into something which is called innovation.

Looking forward to get the brief answers from you guys.

Thanks

Hallo,

I am trying to simulate a fuel cell vehicle in Simulink, however i am confused about the controlling of Fuel cell with dcdc convertor. If anyone can help , I will be grateful. My problem is i am not understanding how to use the control loop or closed loop control system in the model.

What would be the best tool to model an integrated circuit system. There exists several methods like Matlab/Simulink, Verilog A/AMS, cppsim/vppsim and maybe more. Which tool is preferred and why. How is the integration with the exisiting tools ensured. How better data be transferred between environments ?

I am trying to model systems with hydrogen bonding interactions of heavy in which the acceptor is an ion like chloride or bromide. Which level of theory, among B3LYP-D3 and MP2, will be better for modelling the interactions, especially in terms of

**geometry and energetics**? You may also suggest levels of theories which takes comparable time, but yields a better result.

**P.S.:**Although chemical systems are modelled the best using CCSD(T) - the gold standard, but due to large system, the CCSD(T) will be too costly for me.Does anybody have a strong experience of multi-vector energy systems modeling using existing tools?

Suggestions on modeling tools that can do transport, power and heating system modeling in an integrated and dynamic manner while allowing renewable integration and optimisation would be much appreciated.

Hi,

Recently, a lot of data are available to use with NN, especially system modeling. Are you working anything according with robot models, focused in kinematics model?

Best regards.

Something on LEAP would be much appreciated.

I have a physical model for a wall climbing robotic system. I would like to know the procedure to obtain the mass spring damper model for the same. Kindly help.

Do you see any value in the use of SysML for modelling software intensive systems?

SysML is good for building electro-mechanical systems with embedded software components but if you are building a Command and Control software or any other complex software application, it seems SysML is ineffective and does not produce real value (my opinion). I would like to know your opinion and experience on the use of SysML in software intensive systems excluding platform applications such as automobiles or aircrafts.

Thanks a lot.

Alper Akarsu

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.

We all know for a control system, the quality of information (e.g. state info, context info) could have significant impacts on control performance like stability and convergence rate, etc. To theoretically explore such impacts, it is important to adopt suitable system model and corresponding theory. for example, multi-agent system and theory to model coordination control problems and analyze the impact of information flow. In context of cloud computing and IoT more information could be available for a typical control system like traffic control, I just wonder what popular theory framework can apply to such applications? Is there any related surveys to read? thanks a lot.

I have found the spiral dynamics value systems model (Beck & Cowan 2005) an interesting heuristic model but I was struggling to find scientific evidence for its validity. [e.g. The Inglehart-Welzel model (Inglehart & Wezel 2010) from traditional to secular/rational societies seems to correlate the blue to orange value system shift in spiral dynamics but no formal connection has been establised.]

Would you know studies which would back the spiral dynamics model?

If not, would you know better models of human value systems and how they evolve?

I would like to implement IMC (tune the PID parameters) considering a third order integrator system. Most of the existing papers discuss first or second order systems or simplify the system model.

We are looking for methods combining between Partial Order Reduction Technique with Symbolic approaches using BDDs for reducing state space. Could you give us in comments a brief description of such methods you know ?

In quantum physics Gleason’s theorem is generally referred to as an basic property of quantum systems modeled in a separable Hilbert space framework. For instance, John Bell uses this property to prove his theorem. Is the validity of Gleason’s theorem for a system’s model necessary and sufficient for it to be a quantum system model? Are there any publications that discuss and support the answer to this question?

Dear friends,

Can anyone tell me why is there variation in forces for a SDOF system w.r.t. damping when I do linear time-history analysis (direct integration) using SAP2000 for below inputs-

1) Ground acceleration time series excitation, and

2) Ground displacement time series excitation.

I have made a SDOF model on SAP2000 and analysed it for different constant modal damping ratios (0%, 5%, 10%, 20% & 40%) for both type of ground excitation as mentioned above.

For each damping ratio, ABSOLUTE SUPPORT DISPLACEMENT is coming same due to both type of ground excitation.

But the variation in BASE SHEAR is increasing w.r.t. to damping ratio, i.e. for 0% damping, base shear is also same for both type of ground excitation but as I increase the damping ratio, the difference in base shear for the two types of ground excitation is also increasing.

If anyone knows the reason for it, please do reply.

For your further reference, I have also attached a pdf file consisting different graphs for SDOF system models with different damping ratio.

Thanks

Yash Goyal

E-mail- goyal.yash@iitgn.ac.in

Hi...

I know that to evaluate an FIS model i need to write a code similar to the one below:

output= evalfis(input,fismat)

This is easy when my inputs are numbers, but when my inputs are images, what should I do?

And how do I work so that my outputs will also be an image?

Please answer me....

Thanks in advance

please help me to submit my paper in the international journal with SCI/SCIE indexing. The paper focus on Fuzzy Inference system and its application and the title is Study of Mamdani Fuzzy Inference System Model for Flood Event Forecasting in Indonesia. Thank you

If the standard model has been calculated so exactly, then it is surely possible to get that also in a real system model not only in a box of bricks -even with the QCD problem!

I am trying to model systems with hydrogen bonding interactions of heavy in which the acceptor is an ion like chloride or bromide. Which level of theory, among B3LYP-D3 and MP2, will be better for modelling the interactions, especially in terms of

**geometry and energetics**? You may also suggest levels of theories which takes comparable time, but yields a better result.

**P.S.:**Although chemical systems are modelled the best using CCSD(T) - the gold standard, but due to large system, the CCSD(T) will be too costly for me.Hi,

I'm looking for a global scale stem area index data in order to test a new model development which improves stem area index representation in earth system models. Here the stem area index represent for any above ground biomass that does not assimilate carbon- thus, branches, stems and dead leaves are all included. Thanks a lot.

Ming

I was studying islanded Microgrid system model and noticed that all the system models are of closed loop. Is there any open loop Microgrid system? Does any open loop Microgrid system exist?

I am doing analysis with RC Frame System modeled with solid element with embedded Rebars. I proceeded with the step: Linear Perturbation--> Buckle, and used subspace for EigenSolver. However, I encountered an error: "Negative Eigen Values".

How to sort this out in Abaqus? I guess the problem should rise because of inadequacy in constraints or if the model is unstable, however, I don't think I have left any efforts to make it stable and properly constraint. I will appreciate the help. Thanks!

There are many software for system modeling such as MATLAB/Simulink, AMESim, Dymola, Easy-5 etc. They are comparable in terms of functionality. Some are decent for combinations of different type of modelings; for example AnyLogic allows you to combine SD with ABM.

Is there any in which combining SD with DES is possible?

I am working on a thesis titled "Evaluation of Hydrocarbon Potential of Assam basin using petroleum system modelling" for which I need Paleo water depths of different ages as boundary condition.I have different depositionl environments for different lithologies such as Deltaic, Fluvial, estuarine, shallow marine , etc.How can I estimate paleo water depths of Assam basin from these environments.

I'm checking some modelling frameworks (LEAP? TIMES? MESSAGE? EnergyPlan?) to perform the validity of several types of measures regarding city planning, smart measures, etc.

Thank you in advance.

I am studying the production frontier of farm efficiency industry in silvopasture system modeling it as a translog function with Stochastic DEA technique.

I got the estimate efficiency ranking of all the farm households , sigma u , sigma v and Beta k, where k are the inputs used.

system,model ,model equations, estimate A,B,C,D,X from system,

any book,video or practical example that generate data and estimate states it is linear time invariant system thanks.

The optimization of these systems is generally a problem of combinatorial nature, the search for optimum faces a wide field of exploration that could prove costly. For these problems said difficult, many approximation algorithms, probabilistic, heuristic and meta-heuristic.

Its a general question.

For example, I want to design a controller for a nonlinear system to cope with certain periodic disturbance. In order to get a linearized state space model, I linearize the system about certain operating region and state space linear model has no information of this periodic disturbance. how to remove or minimize it. One solution is to use model predictive control where a real system posed to this periodic disturbance is tracking a reference system model (this reference model doesn't included this disturbance into account). I would appreciate if you can suggest a solution other than this.

(Edited)