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System Modeling - Science topic

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Questions related to System Modeling
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My case study has to link existing fashion brands or designers to ’the systems model’ by Howard Gardner. The general idea is that it needs to relate to the impact of The New Economy on brands/designers, but I can’t seem to find a good starting point - any suggestions or resources that you would recommend.
(I understand this description is brief however this is all the information I have been able to coax out of my professors)
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This Model has three critical elements -individual talent, domain knowledge (cultural and technical knowledge) and field influence (brand identity and market relevance) all three are directly related to aspects of fashion design and its publics support and acceptance.
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Effectiveness models of schools, such as Hoy's social system model, Sheerens' integrated model and...
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The effectiveness of a school is directly linked to the implementation of specific guidelines for learning instructions and other activities accepted by educational leadership to improve students' learning outcomes. In 1996, Hallinger and Heck researched school effectiveness and proposed a model that, when consistently followed, enhances learning and promotes effective schools. Their model emphasizes following proper and specific guidelines on learning instructions and other activities accepted by educational leadership to improve student's learning outcomes. Hallinger, Philip, and Heck R.H.(1996) worked on school effectiveness research as Haliger and Merpy proposed a model that when religiously followed will enhance learning and promote effective schools.
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If you are interested in learning system modelling and how it is an important tool for tackling environmental challenges you can join my course here:
last day for registration April 15, 2024.
Regards
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Please i didn't see this on time. I wish to join please.
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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
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A processor in a computer running Windows has two different modes: user mode and kernel mode. The processor switches between the two modes depending on what type of code is running on the processor. Applications run in user mode, and core operating system components run in kernel mode. A simple example to demonstrate the difference between user mode and kernel mode is that of a car driver and a mechanic. The driver is like an application running in user mode, while the mechanic is like an operating system component running in kernel mode .
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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?
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You can take a look at this article for more information
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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
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Hello Fatima Aziz ,
You're welcome! Most of the simulators mentioned can indeed work with offloading algorithms or custom algorithms you write. To integrate your algorithm into the simulator, you may need to create a custom module or modify existing modules to fit your needs.
For instance, in ns-3, you can create custom application modules to implement your offloading algorithm, while in OMNeT++, you can extend existing modules or create new ones to incorporate your algorithm. In iFogSim and EdgeCloudSim, you can implement your offloading algorithm as part of the resource management and scheduling policies.
Regarding Mininet, while it is primarily focused on SDN, you can integrate it with other tools to create an environment that supports mobile edge computing. You might need to explore additional resources, such as ONOS (Open Network Operating System) or OpenDaylight, to create an SDN-based mobile edge computing environment in Mininet.
As you mentioned, exploring the documentation and example scenarios for each simulator will be helpful. Many simulators have active communities and mailing lists where you can ask for help or find resources related to your specific use case.
Good luck with your project.
Best regards!
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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
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Clement Fontana
Thanks Clement! I guess you are referring Global Ocean Colour (Copernicus-GlobColour), Bio-Geo-Chemical, L4 (monthly and interpolated) from Satellite Observations? It looks great!
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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".
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Many of the STS articles which are out there do not follow a prescribed methodology, but rather follow methodological guidance related to whichever field the STS under study resides within. See articles by Frank Geels (2002, 2005, 2007, 2014) for examples. SSM articles, conversely DO follow the prescribed SSM methodology of Checkland (1981).
You could provide an interesting contribution by integrating the two lit streams into one coherent analysis structure.
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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.
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We used MESSAGE on national scale of Syria. Article: Formulating an optimal long-term energy supply.strategy for Syria using MESSAGE model,here in my profle
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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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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!!
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If you want to solve nonlinear differential equations (coupled or uncoupled) you can use 'odeint' function in python language. It uses the RK4 method of numerical integration. To use this function you have to define the nonlinear functions f(x,y), g(x,y) etc from the equations dx/dt=f(x,y) and dy/dt=g(x,y) and then supply these to odeint function as arguments. Along with this, you need to define a time range of integration and initial conditions for x and y.
You can start by solving the differential equation of the simple harmonic oscillator by odeint function in python. The system is defined by two coupled 1st order differential equations: dx/dt=y and dy/dt=-w*w*x. Where w is the frequency of the oscillator. Though it is not nonlinear but you can use this method for nonlinear differential equations also.
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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
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How can we differentiate the terms "prediction" and "forecasting" in system modelling?
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Weather is a good illustration of this difference. We forecast the weather by running a detailed computer model based on physics and meteorology starting at the present and extending out into the future with some assumptions about the boundary conditions. We predict the price of gas (or Twitter stock) next week based on the previous six weeks and a few assumptions (shape of the curve). I have done a lot of work with hydrological parameters, working as an applied mathematician with geologists and hydrologists. In that case I had to infer these parameters (which we can't directly measure) given data that we were able to measure. That was an exercise in nonlinear constrained optimization.
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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.
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s. J Kim A robot control system, in short, manages commands, directs or regulates the movement and functions of various parts of the robot, and executes a specific set of forces and motions.
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Hi,
I am trying to create a full system state space model for an inverter.
References:
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
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Dear Sandford:
You may benefit from these articles about your topic:
1- "System Modeling and Reliability Assessment of Microgrids: A Review"
2- "Control Strategy of Microgrid Inverter Based on H∞ State Feedback Repeated Deadbeat Control"
3- "State Space Modelling and Control of the Modular Multilevel Converter".
.. The pdf file.
I hope it will be helpful...
Best wishes...
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#PSCAD
Does anyone have a readily available IEEE 34 bus distribution system model in PSCAD?
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google it please
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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,
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i think incremental model
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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
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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?
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Try 'AQUASIM'. A trial pack of the same is available with official website.
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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
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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
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It is depend on the size of input vector, type and size of your data. if the size of data is small, you need features extraction. Remember you need meaningful features!
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Optimization of hydrocarbon pipeline transportation and allocation using a pipeline network measurement system model
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You could look for articles with the same topics that you're working on in any database. Then, you could identify the journals where those articles were published, and compile a list of related journals. As Princewill Ikpeka recommended, you could use the SCOPUS database, or even the Google Scholar site (some tips here: https://www.youtube.com/watch?v=dc-vKk205c8). However, you always should make a further review of the identified journals, to validate their scientific quality and credentials.
Best regards!
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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
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Dear Zarzisur Rahman Rony, it should be enough to add a "memory" block (you can find it in Simulink's Discrete toolbox) where algebraic loop occurs (e.g. after "system_approach_first/PV Array/Diode Rsh/Product5") then try with/without setting "inherit sample time" option. This allows breaking algebraic loop and it should work.
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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?
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You may want to check the flags used when compiling the code. When the compiler optimize the code there is the possibility it changes instructions, which can lead to NaN computations. Also change the inputs to the problem to see if the NaNs disappear.
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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)
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The multi-layer perceptron, the radial basis function network and the functional-link network
For more information:
Neural networks for nonlinear dynamic system modelling and identification
S. CHEN &S. A. BILLINGS
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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
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1- Stochastic Model Predictive Control: An Overview and Perspectives for Future Research
DOI: 10.1109/MCS.2016.2602087
2- Stochastic model predictive control — how does it work?
By: panelTor Aksel N.HeirungJoel A.Paulson
3- Stochastic Nonlinear Model Predictive Control with Probabilistic Constraints Ali Mesbah1 , Stefan Streif , Rolf Findeisen , and Richard D. Braatz
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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.
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I agree with Mohamed-Mourad Lafifi
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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
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LEDS-EEP City Energy Planning Toolkit By:
Judit Bálint, Eduardas Kazakevicius, Thor Morante Brigneti
City Energy Planning Toolkit
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I need transfer function for the mathematical model of solute and fluid transport in human kidney for the simulation purpose.
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Mathematical Modeling of Kidney Transport
By: Anita T. Layton
Modeling transport in the kidney: investigating function and dysfunction
By: Aurélie Edwards
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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!
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Relationship between state-space and input-output models via observer Markov parameters
By: M.Q. Phan, R. W. Longman
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Autonomous System modelling
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Intelligent Autonomous Systems, Proceedings of the 15th International Conference IAS-15
Analysis of the autonomous system network topology
  • Authors: Damien Magoni ,Jean Jacques Pansiot
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I am trying to model a MIMO system with several variables. In this, how can identify significant variables to avoid complex system model?
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Identifying the Most Important Independent Variables in Regression Models
By Jim Frost
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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.
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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.
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I am looking at a topic related to transportation modeling
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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.
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In this article, you will find a new in the learning algorithms for the T-S fuzzy models:
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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    
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Matlab (with Simulink) and or SciLab would be useful
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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) ?
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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.
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(continued)
In case of more terms (all with different means m_j>0, j=1,2,...,n) the formulas are as follows (ti replaced by -s)
ch.f.(X_1+X_2+...+X_n)(t) = 1/ [ (1+m_1 s) (1 + m_2 s) ... (1 + m_n s)]
= \sum_{j=1}^n A_j / (1+m_j s),
where A_j = \prod_{k\ne j} [ 1 - m_k / m_j]^{-1}
Therefore, in such cases the density of the sum is equal to
\sum_{j=1}^n A_j / m_j \exp( - x/m_j ), for x>0.
If X_j in the sum is preceded by sign -, then the first two formulas remain valid after replacing m_j by - m_j. The last requires replacing the exponential density for positive variable by the opposite one.
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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?
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I interested
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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
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Hi Bhaskar,
You should check the SoftRobotic Toolkit, I believe it is a very good starting point:
Good luck!
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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...
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This signal can be cleaned from the high frequency noise superimposed on it by an average filtering. You need to sample this signal with the proper sampling frequency and then you can apply the sample on a sliding average filter. Such filter tool kit is associated with the mat lab.
You can use also analog low pass filter to filter out the high frequency ripples. You can use Butter worth filter. You can vary the cut off frequency and the order of the filter till you clean this signal.
With the signal processing tool kit in the mat lab there is no problem with with such type of noise.
I would like also that you see the attached paper in the link:
Best wishes
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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 !
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Hi I am Professor Soheil Sayed Hosseini See my post on satellite control article nmce is availebel
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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
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Dear Muhammad,
The more promising and externally challenging future for robotics in nuclear power plant (NPP). The key rationale of robotics application has always been to avoid human exposure to hazardous environments and tasks ranging from scrutiny and general maintenance to decontamination and post accidental activities. To execute these activities, robots need to incorporate artificial intelligence, improved sensors capability, enhanced data fusion and compliant human like leg and hand structures for efficient motions. Next generation robotic systems in NPPs are expected to work in full autonomous mode in contrast to the current semi-autonomous scenarios. Far future systems could deploy humanoid robots as well. This paper presents state-of-the-art of robotics developed for NPPs, associated challenges and finally comments on future directions.
Key challenges and future:
The primary challenge of robots in NPPs is to ensure safety with precision, reliability and repeatability for any kind of operation in any state at any time under any circumstances. This challenge is due to technological limitations in terms of on-board processing speed, power requirements and unavailability of integrated sensors and actuators, initial robotic systems were highly task specific with little intelligence. The robots were almost unable to cope with any other scenario for which they were not designed. The robotic units were designed with stationary bases and with specific and limited work space. To make use of nuclear power for the benefit of human being in a risk-free and undisruptive manner is another challenge. To achieve this status, in addition to development of superior state-of-art technology, we need to devise better plans and systems to cater for cataclysmic circumstances. Reactor with cooling towers is the most sensitive part of a NPP. Radiation danger in these parts imposes special attentions for all kind of operations in this region and thus this is probably the most desired area of deployment and use of intelligent robotic systems. The challenges in this particular region are coped using various existing branches of robotic units such as mobile robots, stationary industrial arm manipulators or hybrid robots.
System Model:
Simulators and computer modeling techniques are strongly recommended by the International Atomic Energy Agency (IAEA).Here the scopes are dynamic model study of sensitive region reactor with cooling tower. Re-designed robot model efficiency studies with an addition of an extendable arm studies using appropriate payload capacity, environmental hardening, sealed mechanisms and wide range of tools.
Hope it help you out. You would like my explanation.
Ashish
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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.
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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 ?
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Dear Arun,
System modelling and simulation are based on mathematical and logical principles and concepts. It starts with a physical model of the system and then mathematically describing this system by a system of equations normally differential and algebraic equations. To determine the system performance parameters one needs to solve these equations. So, may be one of the best simulators is to use mathematical solving tool which may be from my point of view is the matlab/simulink. This environment in addition contains many specialized model libraries such as Filter design, digital digital signal processing
tool box, logic design tool box, communication tool box ....etc.
This wide utilization is because of easy use script language and the existing aid by the library of models of components, subsystems and subsystem.
There are also associated with it powerful compilers to covert the matlab code to a C-code or a VHDL code.The C-code can be implemented directly on the digital signal processors. The VHDL can be implemented on FPGAs or ASICs chips.
There are tool suits for FPGA design and for ASIC design that acceptsthe VHDL issued by the matlab as an input.
In addition to the matlab there is the ADS that can be a complement for the matlab for the analog system simulation.
Best wishes
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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.
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You add the expression
empiricaldispersion=gd3
In the input file to to represent
B3LYP-D3 method
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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.
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Dear Mohammad, I developed many multi-carrier energy system models in MATLAB environment, if you are good in programming you may follow this way. Here you can find an example of my work on the topic (it is the only one published to date):
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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.
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Dear S.Toquica, in our project we are not using kinematics models for robot control. I do think it would be very interesting and useful for real-world applications.
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Something on LEAP would be much appreciated.
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a few years back, we did some work on biomass using energy systems model. Project details can be found under https://www.psi.ch/en/eem/projects/chp-plant-swarm
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biomedical system modelling
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get the mechanism and bulid the model by ode, then use data to get the accurate parameters
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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.
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You can go through this article it might be helpful:
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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
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The Systems Model (or User Model) needs a Metamodel to ensure consistency between 9 SysML diagrams.
This is terrible a very bad modeling expereince for software intensive systems.
I would suggest you try the Structure-Behavior Coalescence (SBC) Process Algebra (PA) for the software modeling.
The SBC-PA is a metamodel as well as a systems model for software intensive systems.
-----------------------------------------------
Introduction of SBC-PA can be found in the paper
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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.
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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
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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.
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I believe that good starting point is
@ARTICLE{Sar:85,
author = {G.N. Saridis},
title = {An integrated theory of
intelligent machines by expressing the control performance as entropy},
journal = {Control Th.\ \& Advanced Technology},
year = {1985},
pages = {125-138},
number = {2},
}
and I hope that this paper is cited by its successors ... MK
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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?
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Hi Nicolas,
There is a book that in my view backs up the spiral dynamics model, but maybe not in a strictly empirical way (if that's what you are looking for) by 'proving' that the model is historically accurate and that evolution 'in fact' happened this way. (The assumption of an 'objective truth' that could be discovered by empirical evidence is itself problematic.) The book is :
Chapman, Kelly (2015). Complexity and Creative Capacity. Rethinking knowledge transfer, adaptive management and wicked environmental problems. New York – London: Routledge.
It shows in general terms that the current global system evolves towards a higher (emergent) level of complexity and that we reach a point in which all previous (more stable, linear) systems are converging into a planetary interconnected complex (non-linear) flow of subsystems, leading to a new, specifically global dynamics.
In terms of system dynamics this may be the same as stating that the first tier systems converge and we enter a phase of 'second tier' dynamics. Chapman describes the process ontology and cocreative epistemology that will allow us to deal with complex challenges (incorporating e.g. 'indigenous knowledge'). The book does not literally refer to system dynamics, but as a reader I found it useful to link both approaches and explore similarities.
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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.
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You have an output regulation problem and you need to use Internal Model Principle (IMP). Assuming that your output is the first state and the reference to be track is a sinus, you have two options:
1- Use a dynamic controller: the dynamics of your controller should contain a 1-copy of the internal model of the reference signal. If you have p outputs in general, you need p-copy of the internal model. Then, the controller signal is a feedback from its internal state (the controller is dynamics so it has an internal state) and the state (or the output) of your system. This approach is robust.
2- Use a feedforward approach: Design a stabilizing controller for your system assuming that the reference is zero. Then, solve the output regulation equation to obtain the feedforward part. The controller is a sum of these two by some small modifications. Note that this method is not robust if you have uncertainty in the system.
A handy book on this topic is `` Nonlinear Output Regulation: Theory and Applications", by Jie Huang.
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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 ?
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Maybe you could have a look at Sigma DDs:
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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?
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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
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I believe should say more about your problem. What is SAP2000, etc.
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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
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Dear Adel
Did you fixed your problem?
I have an idea
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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
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The procedure of the evaluation of and acceptance of SCI or SCIE is essentially the same. However, it exists a simple difference concerning since tCD/DVD format is used by SCI and online format is used by SCIE. In the following, you see some examples :
SCI journals
  • FUZZY SETS AND SYSTEMS, ISSN: 0165-0114 , ELSEVIER SCIENCE
  • IEEE TRANSACTIONS ON FUZZY SYSTEMS, ISSN: 1063-6706 IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC,
SCIE journals
  • INTERNATIONAL JOURNAL OF FUZZY SYSTEMS, ISSN: 1562-2479 SPRINGER
  • JOURNAL OF INTELLIGENT & FUZZY SYSTEMS, ISSN: 1064-1246 IOS PRESS,
  • IRANIAN JOURNAL OF FUZZY SYSTEMS, ISSN: 1735-0654 UNIV SISTAN & BALUCHESTAN
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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!
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I hope at least with my stereo picture of the "Standard Model" that it is possible to show that what can be done by a very long Lagrange-Formula can also be constructed especially with the new media to get an instant overview direct for the eyes, what's sure better for everyman. The secret-mongering of the Philosopher gets only lost.
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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.
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MP2 is great, but MP2 gradients are expensive and I am not sure about how large your systems are.
If you can afford to use MP2, then you can probably afford to use better DFT functionals than B3LYP - I would look into a good benchmark study, for example;
And pick one of the recommended functionals from there. They even have a breakdown of performance in terms of different chemical properties.
I would probably go with something like PW6B95-D3 and then perform singlepoints with a double-hybrid functional to get the MP2 correlation if nescessary.
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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
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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?
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The necessary power balance condition also requires instantaneous matching between the generation and the load for proper and reliable operating.
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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!
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Please follow this
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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?
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Dear Behzad Minaei,
I think you should take a look at the language Modelica for describing dynamical systems. There are also good open source implementations like JModelica, see http://www.jmodelica.org
You find good teaching material here https://www.xogeny.com/about/
and Mark Tiller has also written a couple of books and one recent book is an e-book for free. http://book.xogeny.com
I have myself used this software to develop applications in biotechnology during the last 5-6 years. Can take some questions if you need.
Best wishes
Jan Peter Axelsson
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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.
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Assuming you have actual rock samples to work with, I agree with Jorge Costa-de-Moura. Benthic foraminifera will give you the best estimates for paleo water depth in shallow water environments, but nanno fossils are much better indicators for deepwater environments. Keep in mind that using micro-fossils is not an absolute answer, but rather a very good indicator. Storms, ocean bottom currents and debris flows can misplace micro-fossils from their original location of deposition. You may have to widen your research area in order to get a more accurate picture.
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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.
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Dear Diego García-Gusano,
here are some literature with methods and tools for Smart City Energy Planning. Some of these may be interesting for you.
Best regards
Anatol Badach
Smart City Energy Planning: Integrating Data and Tools
A new way for Smart Energy Planning in cities: the INSMART solution
Study on City Energy Plan and Control
Extensible Energy Planning Framework for Preemptive Tasks
Methods and tools for community energy planning: A review
GIS-based urban energy systems models and tools: Introducing a model for the optimisation of flexibilisation technologies in urban areas
A review of urban energy system models: Approaches, challenges and opportunities
An Integrated Planning Framework for the Development of Sustainable and Resilient Cities – The Case of the InSMART Project
Research in city energy planning and it's development strategy
Developing a city energy modelling tool and approach
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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.
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Gracias Néstor por tu pronta respuesta, ocurre que no logro entender la diferencia desde el punto de vista gerencial , es decir para toma de decisiones, en construir un SDEA o un DEA , si al final solo tendré un ranking de eficiencia técnica .
En un modelo probabilístico como SDEA debería poder , luego de llegar a un resultado con sus medias y varianzas en un entorno con valores , errores e ineficiencias,contestar algunas preguntas de sensibilidades , como " que. probabilidades tengo de lograr tal eficiencia", si la función de producción para esa firma toma tal valor o si tal recurso o tal producto toman tal valor.
He trabajado con MATLAB y lo he construido según los trabajos de Aigner y Lovell (hay un artículo muy bueno de estimación de eficiencias).
Antes me había zambullido en Tim Coelli y DEAP pero es muy rígido y no me permite modelar sobre otra función que no sea Cobb Douglas porque Translog no me anduvo.
Si estás en este tema quisiera
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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.
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You can see the paper "State and parameter estimation: a nonlinear Luenberger approach"
in which an observer is used to estimate both state and parameters of a linear model.
If your goal is only to find the matrices A,B,C,D you can use least-square minimisation technique based
on your data 'y' and 'u'.
For this, you can fix the order of your model and use one of the controlable or observable canonical forms to represent it.
After that, solve the optimization problem (by using, e.g., fmincon function of Matlab) to find the entries of the matrices
Ac,Bc,Cc,Dc corresponding to one of the canonical forms.
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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.