Science topics: Mathematical Methods
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We suppose,
i- the starting point is to replace the complex PDE for the complex wave function Ψ (probability amplitude) by a real PDE for Ψ^2.
The PDE for Ψ^2 which is the probability density of finding the quantum particle in the volume element x-t dx dy dz dt is assumed exactly equal to the energy density of the quantum particles.
ii- Consequently, the solution of the Bmatrix chain follows the same procedure for solving the heat diffusion equation explained above in the last question:
How to invert a 2D and 3D Laplacian matrix without using MATLAB iteration or any other conventional mathematical method?
iii-The third and final step is to take the square root of the solution for Ψ^2 as the solution for Ψ itself.
As simple as that!
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Note that particle physics is different from wave mechanics because they both have a different physical nature.
The nature of particles is described or modeled as being small and confined to a point in space, while a particle wave is something that propagates and extends almost into infinite free space. Additionally, particles collide and scatter while matter waves refract, diffract, and interfere in a process called superposition. They add or cancel each other in superpositions.
The question arises how can Bmatrix chains describe the seemingly opposite nature via the same matrix?
The answer lies in the specific definition of the boundary conditions in both cases.
Assuming that the boundary conditions in Bmatrix chains are Dirichlet or similar, then they describe a microscopic or macroscopic particle. On the other hand, assuming that the boundary condition extends to infinity, the chains of the B matrix describe the mechanics of wave particles.
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In at least two of mi papers it appears the name Eduardo Almaraz (in this web) instead my name Elena Almaraz Luengo. The papers are:
- Elena Almaraz Luengo; Antonio Gómez Corral. Number of infections suffered by a focal individual in a two-strain SIS-model with partial cross-immunity. Mathematical Methods in the Applied Sciences. 42 - 12, pp. 4318 - 4330. Wiley, 07/05/2019. https://doi.org/10.1002/mma.5652
- Elena Almaraz Luengo; Antonio Gómez Corral. On SIR-models with Markov-modulated events: length of an outbreak, total size of the epidemic and number of secondary infections. Discrete and Continuous Dynamical Systems Series B. 23 - 6, pp. 2153 - 2176. (Estados Unidos de América): AMER INST MATHEMATICAL SCIENCES-AIMS, 06/2018
How can be corrected this in this webpage?
Yhank you in advance.
Dra. Elena Almaraz Luengo
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See "Another researcher has claimed my publications" in https://help.researchgate.net/hc/en-us/articles/14292798510993 for instructions how to correct this. But unlike this help page suggests, most probably it was not the other author himself who wrongly claimed authorship, but ResearchGate's automatic algorithm wrongly identified him as the author and assigned your publication to his profile. This is a frequent problem in ResearchGate in case of similar names.
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Hello, Dear scientific community,
I want to delineate hydrothermal alteration zones using an RGB Band combination on ASTER data. I've already consulted the literature on this topic and I found that 468 is the most relevant band combination for alteration and lithology discrimination. but I want to know if is there any mathematical method to calculate and select the most appropriate band combination.
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You can apply PCA using the ASTER bands. Also, you can try to calculate feature importance using the raster values that can be extracted from different ASTER bands after a visual inspection of various color composite images (ASTER bands and PC bands). From the analysis of feature importance, you could get an idea of best optimum bands that can be used for your study. Mohammed Jalal Tazi
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I'm working on detection of seismic P-wave so I read about different type of mathematical methods. recently I was working on AR-AIC method but I saw some inconsistent with the main article in results so I am looking for another MATLAB code for evaluate my own code.
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You can use methods based on wavelet transform.
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We assume that there is a complex story deeply hidden behind double and triple integration.
This is the reason why the current definition of double and triple integration is incomplete.
Brief,
Time is part of an inseparable block of space-time and therefore,
geometric space is the other part of the inseparable block of space-time.
In other words, you can perform integration using the x-t space-time unit with wide applicability and excellent speed and accuracy.
On the other hand, the classical mathematical methods of integration using the FDM technique in the geometric Cartesian space alone x can still be applied but only in special cases and it is to be expected that their results are only a limit of success.
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Double and triple integration are mathematical tools used to calculate the area and volume of regions in two and three-dimensional space, respectively. These integrals are extensions of single integration, which is used to calculate the area under a curve.
The calculation of double and triple integrals involves dividing the region of interest into smaller pieces and summing up the contributions from each piece. This process can become very complex, especially for irregularly shaped regions.
However, the use of integration in spacetime is a concept from physics, where time is treated as a fourth dimension in addition to the three spatial dimensions. In this case, integration in spacetime is used to calculate quantities such as the trajectory of a particle or the spacetime interval between two events.
In the curved spacetime of general relativity, integration is over the Riemannian spacetime. The volume element in this curved spacetime is 4-dimensional and, in principle, the general solution requires a quadruple integral (special cases integrate along a contour which is out of the topic). The 4D volume element in the curved Riemannian spacetime necessarily includes the Jacobian determinant which transforms the flat 4D Galilean spacetime coordinates used in special relativity to the curved Riemannian spacetime coordinates. For the above transformation of coordinates, it is proven that the Jacobian is equal to sqrt(-g) where g is the determinant of the spacetime metric. Thus, all integrations include the 4D volume element dOmega multiplied by sqrt(-g) which corrects for curvature by the respective changes in the measurement units (for length and time).
For more details, you can read the last section of my preprint named "Metric density and metric determinant and why they are important".
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As H.-J. Bunge defined, crystallographic orientation refers to how the crystallites in a volume of crystal (crystal coordinate system) are positioned relative to a fixed reference (specimen coordinate system) . There is a trending pattern in the orientations that are present and a propensity for the occurrence of certain orientations. This crystallographic orientation of the crystallites with the polycrystalline aggregate is known as preferred orientation, more concise texture[1].
If all possible orientations of crystallite occur with equal frequency, the orientationdependence will disappear on average. As W. A. Dollase defined, the axially symmetric flat-plate sample can be composed of effective rod- or disk-shaped crystallites. This shaping effect is also named as preferred orientation[2].
[1] Bunge, H.J. Texture Analysis in Material Science. In Mathematical Methods; Butterworth & Co.: Oxford, UK, 1982; pp. 1–5.
[2] Dollase,W.A. Correction of Intensities for Preferred Orientation in Powder Diffractometry: Application of the March Model. J. Appl. Crystallogr. 1986, 19, 267.
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The preferred orientation could be interpreted in two ways (in my understanding). One what thermo-mechanical properties favor and what we intend to have in the material as a requirement favoring intended properties. For example in ferritic stainless steels the preferred cast texture is {hkl}<001>. Similarly, in FSS, during thermo-mechanical processing recovery precedes re-crystallization and results in texture {001}<110> and 001}<110>.
In Ferritic stainless steels for better formability properties {111}//ND texture is intended; hence the thermo-mechanical processing is optimized to instill recrystallization to increase the volume of {111}//ND orientations than the cube or Goss orientations. In this case all the orientations are preferred orientations depending upon the processing of the material. This intended preferred orientation would change on the application of the material.
Coming to the Texture, all the major orientations in the material could be defined as Texture.
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Calculates the optical gap.
Please, is there a mathematical method to calculate the optical gap directly from the transmittance without going to the graph method (the slope)?
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I want to learn more.
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I came across this question (attached below). I tried to solve it but got stuck in the portion where we need to calculate the inverse tranform. I found a solution of this question (also attached below) but there, in the encircled portion, I couldn't get how they took a 2x factor out and change the limits from (-∞, +∞) to [0,+∞ ). I know that we can do this changing of limits only if it's an even function and can take the limiting points [0,+∞ ) iff the function is of the form y = ax2 . But here the term inside the exponential function is of the form y = ax2 + bx + cix, where i =complex number, and accordingly the limit should change to some random [m,+∞ ) in place of [0,+∞ ). Also, the 2x factor would not be there because the limiting point is changing from [0,+∞ ) to [m,+∞ ) and the graph will not be symmetrical across X=0 Axis.
I will be highly grateful if you can kindly clarify my doubt or let me know where I am making a mistake in understanding the question.
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I love your equations. Please keep us in the loop.
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There are many methods based on the stochastic arithmetic and also floating point arithmetic. What is advantage and disadvantage of the mathematical methods based on stochastic arithmetic?
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Dear Prof. Dr Imtiaz Husain
Thank you for your answer. I have some papers about the applications of the stochastic arithmetic. But I need to know more and real applications.
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Scientists and engineers solve physical and mathematical models containing tens and hundreds of SI variables, and take into account a larger number of potential effects of interaction between them, using super-powerful computers and developed advanced mathematical methods. But this requires significant time and financial resources. In addition, with the current rapid development of science, the situation with the identification of truly revolutionary discoveries is complicated by the complexity of their identification (the idea of ​​incommensurability of scientific theories): supporters of each paradigm see the world in their own way because of their scientific training and previous experience. They use a different conceptual framework and different ideas about scientific standards.
Is there a limit to our knowledge?
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Your remark : " A tool is only as good as the person using it."
For me it is difficult not agree with you.
At the same time, I would like to put your attention once more on ONE point:
Person (scientist, engineer, observer, he or she) formulates his vision of the physical pnenomena basing on his knowledge, life experience and intuition - one can say - phylosophical opinion.
As a physical-mathematical tool for formulating a model, he uses different variables from any system of units (SI, SGS, Plank system and so on.). There is no other way.
My problem (and I try to convince scientific society) is:
If any system of units consists of the finite number of variables (read my articles) and a model includes the finite amount information (read Del Santo, F., & Gisin, N. (2019) Physics without determinism: Alternative interpretations of classical physics. Phys. Rev. A, 100, 1–9.
there is the initial inevitable blurring of the object that is being studied by the observer.
This explains the impracticability of achieving infinite precision!
Do you agree with this ???
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Hi all,
I attached an image file of excel data in which the problem is to predict the value of u by using any mathematical method.so, please share me the procedure or method to be followed to solve the problem.thank you in advance.
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You search data imputation in internet there are many tools to predict the missing values.
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Most MCDM problems use subjective weights mainly obtained from AHP.
These weights are developed by preferences, qualified using a dubious table (as is the opinion of many researchers), and criticized since decades ago.
They are also obtained under the aggravating circumstance that the DM works only with criteria without considering the different projects, WHICH THEY MUST EVALUATE, according to AHP hierarchy.
That is, in comparing, say environment and disposable income, the DM decides, by intuition, that the first is more important than the second, and assigns a numerical value to that preference, using values of the above-mentioned table.
Then, this assumed weight, for it is not a weight, but a trade-off value, is used to select alternatives. On what grounds? None given.
Consequently, the DM decides that said preference is valid for everything in life, since he does not have any reference, other that a single objective, where this preference will be used.
Not too much thinking is needed to conclude that this process is invalid, because that preference may apply well to a certain project but not in others, or even in comparing alternatives within a scenario.
Now, the DM, using mathematical methods (The Eigen Value method, or the Geometrical Mean), determines priorities for each criterion - after his estimates are subject to the verdict of a formula - because the method demands that his estimates MUST fulfill, with a 10 % of tolerance, that they are consistent, or that meet transitivity.
That is that if criterion A = 3 times more important than criterion B, or 3B, and B =2C, then A=6C.
Now, one wonders why his estimates must be transitive?
Nobody knows, but what is worse, is that the AHP method assumes that said transitivity MUST also be satisfied by the real-world problem, not considering that in general, the world is intransitive.
And now the question:
On what ground, on what theory, on what relationship is it assumed that those preferences from a DM or from a group of DMs, are valid for the real world?
As a matter of fact, a very well-known theorem, the ‘Arrow’s Impossibility Theorem’, says the opposite.
I have posted several times this question. Is there anybody that can give a RATIONAL answer?
Your response and discussion will be greatly appreciated.
Thank you
Nolberto Munier
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Hello Dear Professor @Nolberto Munier
I will meet you after a long time with a challenging discussion!
Contrary to previous discussions in late 2020, I feel that your critical theory is significant and close to reality!
I love AHP and especially ANP, especially the fuzzy version of them!
But the fact is that you are right, these methods have a logical flaw!
A kind of imposition and transmission of opinion!
Good luck
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What mathematical methods are helpful to correlate the values of laboratory and Production results of extrusion ?
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Thankyou for guiding. I will do it and based on the outliers, I will decide what correlation coefficients or MAE is to be used Andrey Davydenko
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Gaussian noise and speckle noise are the examples of linear noise whereas salt-and-pepper noise and uniform impulse noise are nonlinear noise. Gaussian noise can be expressed in the form of its mean and variance values while speckle noise can be modeled by random values multiplied by pixel values. In a nonlinear group, salt-and-pepper noise corrupts the image’s pixels randomly and sparsely that makes some pixel changing to bright or dark.Uniform impulse noise is characterized by replacing a portion of some image pixel values with random values. The switching bilateral filter (SBF) is one of the most effective filters that is proposed for the mixed noise removal in images. The performance of the SBF is controlled by two parameters, the values of the radiometric weight (sR) and the spatial weight (sS). The proportional values of these parameters depend on three important factors which are level of noise, the type of noise and the type of image. Generally, the most of noise removal techniques can be used to perform noise reduction when the image is contaminated with only one type of noise [6]. Nevertheless, currently, the images may corrupt by more than one types of noise. Then, former image noise removal techniques cannot remove the noises efficiently.
Papers:
Y. He, Y. Zheng, Y. Zhao, Y. Ren, J. Lian and J. Gee, “Retinal Image Denoising via Bilateral Filter with a Spatial Kernel of Optimally Oriented Line Spread Function”, Journal of Computational and Mathematical Methods in Medicine, Vol. 2017, Feb 2017.
K. Langampol, W Lee, and V. Patanavijit, “ The switching bilateral denoising performance influence of spatial and radiometric variance” , ECTI-CON 2016, Jul 2016.
M. K. Raijada, D. Patel and P. Prajapati. “A review paper on image quality assessment metrics”, JETIR, Vol. 2, Jan 2015.
W. Phummara, K. Langampol, W Lee, and V. Patanavijit, “An optimal performance investigation for bilateral filter under four different image types” , SITIS-2015, pp. 34-41, 2015.
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Dear Eduard Babulak , Please refer to this link, you may find some answers: https://urlz.fr/c3XF
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I am trying to design a caching strategy for ICN-based IoT which will use the popularity for caching the content. if someone kindly tell me what is a good way to measure popularity. a link to a research article or any reference to a mathematical method will be highly appreciated.
thanks in advance
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Right now I dont have any, but you will find few, please search at google scholar
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In the author's interpretation we consider concepts and methods of science, such as science, knowledge, model, gnosticism and agnosticism, the principle of Ashby, facts, empirical regularity, empirical law, scientific law, and others. We have formulated the main problem of the science, concluding that cognitive abilities of a human are limited and do not provide effective knowledge in a very large volume of data. The solution to this problem is to look at ways of automation of scientific research. Traditionally, we use information-measuring systems and automated systems research (ASNI) for this. However, the mathematical methods used in these systems, impose strict impracticable requirements to the source data, which dramatically reduces the effectiveness and applicability of these systems in practice. Instead of having to submit to the source data impracticable requirements (like the normality of the distribution, absolute accuracy and complete replications of all combinations of values of factors and their full independence and additivity) automated system-cognitive analysis (ASC-analysis) offers (without any pre-processing) to understand the data and thereby convert them into information and then convert this information to knowledge by its application to achieve targets (i.e. for controlling) and for solution for problems of classification, decision support and meaningful empirical research of the modeled subject area. ASC-analysis is a systematic analysis, considered as a method of scientific cognition. This is a highly automated method of scientific knowledge that has its own developed and constantly improving software tool – an intellectual system called "Eidos". The system of "Eidos" has been developed in a generic setting, independent of any domain and can be applied in all subject areas, in which people apply their natural intelligence. The "Eidos" system is a tool of cognition, which greatly increases the possibility of natural intelligence, just like microscopes and telescopes multiply the possibilities of vision (but in this case only if you have this possibility). The study proposes a new view of the models: phenomenological meaningful model, which is currently represented only by systemic cognitive models, and which is currently in the middle between empirical and theoretical knowledge. The system called "Eidos" is considered as a tool of automation of the learning process, providing meaningful synthesis of phenomenological models directly on the basis of empirical data
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Hi.,
Cognitive automation is based on software bringing intelligence to information-intensive processes. It is commonly associated with Robotic Process Automation (RPA) as the conjunction between Artificial Intelligence (AI) and Cognitive Computing.
Intelligent automation empowers humans with advanced smart technologies and agile processes for faster, more intelligent decisions. The key benefits of IA in business include: Increasing process efficiency. Improving customer experience.
For More info:
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Scope
Biomedical imaging has emerged as a major technological platform for disease diagnosis, clinical research, drug development and other related domains due to being non-invasive and producing multi-dimensional data. An abundance of imaging data is collected, but this wealth of information has not been utilized to full extent. Therefore, there is a need for introduction of biomedical image analysis techniques that are accurate, reproducible and generalizable to large scale datasets. Identification of imaging patterns in an anatomical site or an organ at the macroscopic or microscopic scale may guide characterization of abnormalities and estimation of disease risk, analysis of large scale clinical datasets, and assessment of intervention therapy techniques.
This special track solicits original and good-quality papers for delineating, identifying and characterizing novel biomedical imaging patterns. These methods may aim for segmentation, identification and quantification of anatomies, characterization of their properties, and classification of disease. These approaches may be applied to radiological imaging such as CT, MRI and ultrasound, or imaging at the cellular scale such as microscopy and digital pathology techniques.
Topics
Topics of interest include, but are not limited, to the following areas:
Machine/Deep Learning for Computer-aided Diagnosis and Prognosis
Biomedical Image Segmentation and Registration
Radiomics, Immunotherapies, Digital Pathology
Cell Segmentation and Tracking
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It's a great topic.
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  • let say if there are X1, X2, X3, X4,....................Xn factors and each factors depends on i (i=1,2,3,4...........) factors and N=25 factors of manufacturing performance.
if let us say
  • X1= f (X2, X3, X4, X5............Xn) (i=n)
  • X2= f(X1, X3, X4, X5............Xn) (i=n)
  • X3 = f(X1, X2, X5, X6............Xn) (i=14)
  • and so on.
  • I want to know the level of dependence of each factor on other factor. eg what is the dependence level of factor X1 is on factor X2 and how much is the level of dependence of X2 on X1. Level of dependence of factor X1 to X2 and X2 to X1 are different. how such a model can be analyzed using statistical methods. please refer to the figure for further clarity.
  • Please suggest some statistical/Mathematical Method or technique. this problem is related with the factors influencing the manufacturing performance but these factors are also influenced by each other to a large extent. so basically if one parameter changes it automatically affects all other performance parameter.
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Dear Abdul Gani,
In this situation you can use structural equation modeling (SEM).
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What is the suitable method to forecast solar irradiance? What is the advantages to use ANN method compare with another statistical method?
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you may check the following interesting paper
Review of solar irradiance forecasting methods and a proposition for small-scale insular grids
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Mathematical and computational methods are expected to play a major role in nanoscience and nanoengineering. Mathematics and computation can provide effective theory and simulations for analysis and interpretation of experimental results, model-based prediction of nanoscale phenomena, and design and control of nanoscale systems.
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Reminds me of: 'In theory, theory and practice agree. In practice they do not'
I would always believe one well-conducted experiment over one paper with more Greek letters than an Athens post-office.....
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When talking about the transmittance, scholars mostly use the transmittance at 550 nm to represent the sample's transmittance. Why is that? In UV-visible absorption spectroscopy, is it scientific and reasonable to choose the transmittance at 550 nm to represent it? Or is it necessary to calculate the overall transmittance of the sample by integral or other mathematical methods?
Thanks for your answers. Are there any suggestions for relevant literature?
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If we look at the sun radiation spectrum, it is obvious that 550 nm is near the wavelength which has the maximum power can get from the sun. So for making a standard wavelength to compare T and A with others, it seems that 550 nm is a good choice!
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If another mathematical method(s) is/are used to solve the resulting equations of zeroth order, first order, second order,..., especially for providing solutions to PDE, can we then regard homotopy perturbation, regular perturbation and singular perturbation methods as stand-alone approximate analytical methods ?
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While using these approximate methods surely you will get the linear systems if possible you can get the exact solutions of these system otherwise you can compute the solution with the help of any approximate method. Usually the purpose of these methods are to linearize the problems and then find the solutions exactly like, eigen function, separation of variable, Laplace transform, Fourier, Greens function or many other where applicable. Symmetries are also useful if workable.
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Je sui en train de travailler sur l'Ouvroir de litterature potentielle, le group de litterature francaise qui comprend Queneau, Perec, Calvino etc. Mon bout est de trouver une production contemporaine qui s'inspire de leur method mathematique
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Je connais l'oueuvre de certains auteurs passionnés des jeux mathématiques comme Luisa Valenzuela, Marius Serra, Guillermo Cabrera Infante -"Exorcismos de esti(l)o" y Jorge Luis Borges -"El libro de arena"-. Vous pouvez consulter sur Borges l'excellent BORGES Y LA MATEMÁTICA, de Guillermo Martínez.
Je vous conseille aussi la thèse doctorale de Pablo Martín Sánchez EL ARTE DE COMBINAR FRAGMENTOS (Universidad de Granada, dans l'URL
et les travaux de Lidia Morales Benito, que présentera sa thèse sur ce thème par rapport à Guillermo Cabrera Infante.
Cordialement.
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Any idea about equations and mathematical methods that can be derived to develop predictive models that will allow scaling up results from membrane bench scale experiments to large scale applications?
Many thanks
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Can anyone suggest me any book or paper for indication of developing faults using IEC 61850-9-2 based current and voltage values?.
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The main aim is to evaluate the kinematic disorders in multiple sclerosis patients by using an intelligent mathematical method.
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Dear Ramona ,
Thank you for your answer but the paper not available to download. Can you send it to me please!
Regards
Amr
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In my question here is to seek and to know if there is any paper discussed Borel summability for non analytic divergent power series but smooth ( Smooth for real valued function) , I assume that the power divergent series convergent only at origine x=0 , and one can get a formel power series in that case .
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Thanks so much for your answer
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Most Engineer use nonlinear system than linear system, but the mathematical methods is difficult for nonlinear.
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Hi Nasser,
Nonlinear systems are complicated because of the high dependency of the system variables on each others. I have to tell you that Most of the Engineers are using linear systems in their analysis. Before start solving any Engineering problem we try do linearization to get a linearized model. That is because, the nonlinear problems are difficult to solve and are so expensive. However, linear problems give very close solution to the nonlinear ones with less cost, time and effort.
I can list you many different examples of solving nonlinear problems with a linearzied model if you want. But I think it might be enough to mention simply why we are perform linearzation to solve nonlinear problems.
Best regards
Mohamed
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We are interested in applying mathematical methods from optimization, machine learning and experiment design to enable scientific discovery and new industrial applications of SEM/TEM and related imaging techniques.
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This is the 2000th Fibonacci number :
4224696333392304878706725602341482782579852840250681098010280137314308584370130707224123599639141511088446087538909603607640194711643596029271983312598737326253555802606991585915229492453904998722256795316982874482472992263901833716778060607011615497886719879858311468870876264597369086722884023654422295243347964480139515349562972087652656069529806499841977448720155612802665404554171717881930324025204312082516817125
Regards
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To measure the activity of dehydrogenase, the amount of formazan TPF (mg) is used to determine the specific weight of the soil for a certain time.
In different studies data are given for 1 minute, 1 hour, 24 hours. Weights also differ 1 g or 10 g. Is it possible to bring these results into a single species for comparison? by translating one or using some mathematical methods?
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Dear Mariia Polzyk
U could very well convert the expressed values to the required one.
If your value is mg TPF/10 g soil dw/24 h, u can convert it to mg TPF/ g dw/ 24 h by dividing your value with 10. Similarly other reported values also can be converted to the expressed value for comparison.
Hope this answer helped you !
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Hello everyone! We're currently working on a research about improving pharmaceutical supply chains using lean tools. In this work, we've encountered a problem that should be solved before we proceed. The problem/question is: is there any (mathematical) method or any other tools to determine the relationship between variable lead time and waste reduction (or the effect of variable lead time on waste reduction)? How to find one? Any advice and thoughts would be appreciated!
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Perhaps you could have a look at the Kingman equation (or VUT equation).
If you examine the definition of the utilization variable you find the link to waste. Even if the equation does not fit your situation exactly (it assumes G/G/1) it provides a startingpoint.
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Partial discharge in gas  has some symptoms such as chemical reaction, sonic and electromagnetic emissions. Which numerical software is proper for these kind of simulations that can address all of physical effect due to partial discharge?
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@khalil , aspentech is more likely a process control tool for supply chain ! are you sure it address myultiphysics?
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To determine the mean river Width in sections, there are different methods. As you know, rivers shape isn't an unique shape and I can't calculate it by mathematical methods that usually we used in numeral shapes. I can calculate the area that covered by channel (A) and the length of flow (L) in study section, can I use this typical equation "A/L=w"?
Regards.
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Have a look at this R solution. It calculates the channel width locally for any given river shape. https://github.com/AntoniusGolly/cmgo
It does this by first calculating a centerline and then transects. You can later set the spacing of the transects.
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Hello, I am looking for a mathematically method to qualification range of some indicators. i mean when i have some quantify indicators, how can i understand are that low, high or moderate? can you help me?
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Dear Maryam,
Decision-Making Trial and Evaluation Laboratory (DEMATEL) method can also be used as mathematical approach for quantification of performance indicators. 
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Let A generate a strongly continuous semigroup T(t) on. X, B from U to X_{-1} be an admissible control operator for T(t), C X_1 to Y be an admissible observation opertator for T(t),  Let K from X to U be a linear operator. The statte feedback control law
u(t)=Kx(t)+v(t).
under what condition for K, the closed loop is well posed.
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Baed on the property of the state feedback control law, I gave an definition about admissible state feedback operator K.
Definition
A operator K X_1 to U is said to be an admissible state feedback operator for (A, B) if
(A, B, K)  and (A+BK, B, K)  are   L^p well posed..
This defition can remain the v(t)=-BK x(t)+u(t) also is a  state feedback control.
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What is the best mathematical method to smooth and calculate the acceleration of soccer players from 2D positional data (i.e. [x,y]) ?
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I am new in data analysis and trying to identify and delete outliers from original data when doing T-squares analysis.
I have 150 data in a vector(150 rows and 1 col) which have 10 outliers
I would like to remove the outliers from these data in order to prepare that
for ANN learning,
So, I analyze this data by T-squares method and plot of this method show outliers in the normalized data obviously,
but I would like to have a way to mathematically delete these detected outliers from original data (not normalized data)
any suggestion or ideas to aid me in doing that is greatly appreciated.
Thanks in advance for your help.
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The attached paper may be helpful. The psi functions in this paper could be replaced by the bisquare as Hassan suggests. To use the program with your data simply use a regression model that only has a constant term in it.  For the analysis using R, see the link below. Best wishes, David
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Dear Researchers
I am solving a set of non-linear equations both numerically and mathematically. The numerical method is based on 4th order Runge-Kutta. Under some conditions (Chaos and bifurcations), the mathematical method results in multiple solutions, however, the numerical method only converges to one of the solutions. what is the way of controlling numerical method to extract all possible solutions?
Appreciating your time, looking forward for your answers.
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@Saeed
If, the right-hand side of your non-linear ODE of first order does not depend explicitely on time and, in particular, does not contain a periodic driving force term, why you described your problem to Professor Rath as analog to the Huang Su Chen paper? (This paper deals with periodically driven problems for which all solutions depend nontrivially on time).
In the framework which you now suggest the word 'response' makes no sense, since there is no stimulus.
Does 'want to solve the diffferential equations again' mean that you vary the initial conditions of your Runge-Kutta integration? If yes, according to which plan?
I understand that you refrain from reproducing the ugly numbers from your funcC.m file. But it should be possible with limited effort to make clear on which variables the right-hand side of your ODE depends. In particular: does time come in in any other form than X_i(t), i=1,...6 ? E.g. as f_0(t) ?
Given that Andrew pointed out that finding steady-state solutions is not a differential equations problem at all, and that I indicated that 'steady-state solution' may here used in a meaning different from Andrew's interpretation, I would have expected clear words from you what your definition of steady-state solution is.
There is still a bit of hope on my side that the whole discussion may make sense in the end.
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You need to read first definitions 1-9, and then realize whether or not Lemma 1 is correct. I think I've found a counterexample, with five objects and two attributes, but maybe I got wrong the definitions.
The example is:
o1(0, 0) in class 1
o2(0, 0) in class 2
o3(0, 1) in class 3
o4(0, 1) in class 4
o5(1, 0) in class 5
For that case the sets of reducts with the usual decision, and with the generalized decision (using definition 8, i.e. REDpos) are not the same to me, so contradicting Lemma 1.
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Sir sorry I will leave that information for you to figure out seems as though, you maybe on to something perhaps. Go for it Sir! Good day! (RSR) Rough Set Reducts! I know nothing about sorry Sir good luck!
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During the last quarter of the twentieth century, the electromagnetic force binding atoms and molecules and the weak nuclear force governing the decay of radioactive matter were merged into a single theory asserting them to be different manifestations of one and the same force-the "electroweak" force. Crucial parts of this theory have been confirmed at the world's most powerful accelerators at CERN and Fermi Lab, and concerted efforts are now under way to extend this unified theory to include the strong nuclear force that binds elementary particles within nuclei. Furthermore, although scientists are unsure at this time how, in turn, to incorporate into this comprehensive theory the fourth known force (gravity), we have reason to suspect that Einstein's dream is nearing-to understand all the forces of Nature as different aspects of a single, fundamental force.
In this article, according to the experimental observations, the Maxwell equations of electromagnetism is generalized to the gravitational field.
The strong interaction or strong force is today understood to represent the interactions between quarks and gluons as detailed by the theory of quantum chromodynamics (QCD). The strong force is the fundamental force mediated by gluons, acting upon quarks, antiquarks, and the gluons themselves.
This article shows how homonymous charge particles absorb each other in very small distance. Generally, two homonymous charged particles produce binding energy, in small distance. This looking where based on CPH theory and it is continuing of Graviton and virtual photons.
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hi
Some comments after reading this article:
Graviton and virtual photons by Hossein Javadi
Part of his conclusion:
Attention to photon structure and using new definitions for graviton, charged and exchange particles, will change our perspective on modern physics. It also provides us with a new tool to be able to overcome physics problems in a better way. This approach will show us how particles are formed.
In the introduction, he writes: If we continue to believe that in the Standard Model, elementary particles are point particles and unstructured, we cannot resolve ambiguities in modern physics.  
Looking at the effect of light on gravitational forces, points out in the same direction. See Further Experiments Demonstrating the Effect of Light on Gravitation
Louis Rancourt, Philip J. Tattersall
If we look at the electrons and nuclei as very complex systems made of maybe as much as 1030 parts, then we cannot look at them as point particles with no internal structure. When light meets what makes the gravitational force at 90 degrees, it interacts with it and the amount of force of gravity changes after that. An object under the light beam looses weight and an object above the beam gains weight. Nothing predicts an increase of gravity like that.
To explain this interaction, one does not need to give a property of mass or charge or any other property to what makes that beam of light or what makes gravity.
If all elementary particle are complex systems, their parts are always moving at the speed of light in relation to free space. The internal speed plus the speed of the system is always c.
When gravity acts on the system. it does not give energy to the system but becomes part of the system and the total direction of the system changes. Thus gravity does not have to have mass because what makes that gravity is the same as what makes light, no mass, no charge just a being moving at speed c. To visualize what happens, it is important to always look a an object as something moving in space and not static. There is nothing in the universe that has no movement.
Hope these comments will help to better understand matter.
Louis
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I am modelling an Organic FET. By making some empirical adjustments in conventional siMOSFET current equations I got a good fit in the linear regime of output characteristics ,but, when it goes to saturation regime the slope of the cure becomes discontinues. I am looking for a mathematical method to solve this problem, your suggestions would be appreciated, Thanks in advance . 
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I suggest look at at unsaturated soil mechanics text books and papers. Probably you find some equations for desaturation  or saturation impact on slope stability.
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I am new and don't know exactly,what to do other than rheometer determination?
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Hi. you can design an appropriate  test specimen out of your material, that is capable to perform a free decay test (means: you impose some impulse loading and observe the free decay of the oscillation. take care to excite only one mode...). From the measured free decay response (time series of displacement)  you can determine the logarithmic decrement as a measure of energy dissipation. the logarithmic decrement can be related to a loss angle or other damping measures under some assumptions. But you get the material properties only for one (or few other) excited natural frequencies; for a more complete characterisation of material properties (e.g. for polymeric materials)  dma-tests (dynamic-mechanical analysis) might be more promising...
Regarding FFT based damping identification see following technical review for some ideas. regards
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Hello everyone, 
I need fast mathematical methods to calculate (or estimate) eigenvalues/vectors for large scale matrices (just above 100000 dimensions). Would you please introduce some state-of-the-art references for this issue?
I want to thank you in advance for your kind support.
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Rational Canonical Form (RCF) can be useful for this problem. After diagonal matrix obtain by the method, eigenvalues can be found easily.
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I am interested to work about a shock wave phenomena in supersonic flows.
Is there any mathematical method by which a shock wave can be detected in such flows? 
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Shock waves have been studied for a long time, but still there are numerous questions that need answering in the field, even very basic ones. I suggest you start reading books on gas dynamics, such as the one by Liepmann and Roshko, to familiarize yourself with the field. You can study shock waves using analytical, experimental and computational methods. If you are interested in the analytical (mathematical) side of it, please start with Method of Characteristics.
All the best.
- Chintoo.
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I want to interpolate velocity field in seismic fault zone, which physical/crustal model could I combine with? Except mathematical method like KRIGING.
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Hello again Yu Jiang. I am sorry I didn't catch that you weren't in geophysics, geomecanics is great, by the way!. I am not sure how you could do what you want except from a strong geostatistical analysis (Krigin and multidirectional variograms) but I have seem some thesis that take the end result from GPS data and input them into complex mechanical models. Some thing like a 3D finite elements model where plates simulate an strike slip fault. Good luck with your work!  
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Ratios, in addition to frontier analysis, is one of the statistical/mathematical methods used for measuring efficiency.
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Hi Ariel,
In my studied sample of hospitals, sometimes the extreme values of the indicators ALOS, BTO and BOR may be caused by reasons that do relate to efficiency, like unnecessary long stays for example, or unnecessary admissions. and such problems, when diagnosed, can be modified to improve efficiency, this is what I am proposing in my research.
Do you have any recommendations for an efficiency measure that is as simple as Pabon Lasso and doesn't need too much data? because I'm a little bit restricted to the limitation of data availability in the hospitals of my sample.
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In many isolated communities there may be plenty of choice and limited availability of energy resources. If you want to plan the rational use of this resource in a possible energization of the community, it is necessary to do tranves of mathematical methods. There are many mathematical methods applicable to isolated rural context.
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Dear Lazaro
this is a good question as the mathematical complexity depends on the type of energy streams you supply to the rural community and if you want to manage energy supply and demand based on microgrid or smart microgrid principles.
we were looking at a layered approach in one of our publications
the intermittent nature of renewable energy resources complicates the problem in an isolated microgrid since you will need forecasting techniques in your mathematical modeling. 
Trust this helps
Gerro
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I have some morphometric measurments (carapace width, carapace length, weight etc.) of about 1100 adult crabs. I would like to know if there is any method to calculate age structure of these crabs? Any mathematical methods? Have you got any publication on this topic
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There is no good method for aging crustaceans. However, two techniques have been used. One is measuring lipofuschin in the nerves of crabs and lobsters. Do a search on Matt Sheehy for his papers on the subject. This one is an early review: http://link.springer.com/article/10.1007/BF01313426. The other method is more recent and uses age bands or molt bands. http://www.nrcresearchpress.com/doi/abs/10.1139/cjfas-2012-0254.
You will likely not be able to age your crabs based on morphometric measurements, unless you have done tagging studies and even those can be difficult. 
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I've modeled the OFDM technique, so can involve the appropriate advanced mathematical methods at any stage, to get the best detection.
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thier are many methods described in literature. The performance of such detectors depend mainly upon the kind of channels the ofdm signals are experiencing.  low complexity detection of OFDM signals over time-varying channels can be done by (MMSE) based block equalizers. The performance of these receivers has been
further enhanced through iterative detection and interference cancellation algorithms.
data detection over highly time-varying channels and propose a new demodulation
technique called partial FFT demodulation.
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I am Looking for the latest advanced mathematical methods  to use  in the OFDM system, especially in detection process.
I've modeled the OFDM system, that it can involve data at any stage I want.
Is there an advanced mathematical model to serve this  technology?
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It seems that he/she is interested to know the math fields  used for OFDM based systems especially for evaluating the detection. I would say that Fourier transform and series, probability theory and linear algebra are mostly employed.        
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See above.
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Self consistency deals with a coupled solution of Schrodinger and Poisson equation.
Charge distribution is calculated from the wave functions calculated using Schrodinger equation. Next this charge distribution is put into Poisson eqn to predict the potential distribution which is again used in Sch eqn. This process is repeated with iteration and ultimately stopped when the solution converges.
It gives the actual charge as well as potential distribution inside the  structure under consideration.
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Just as that we make use of the Gaussian function for infinite dimensionals.
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This is misleading. There is all the difference in the world between the heat equation and the Schrodinger equations, since one is dissipative, the other is oscillatory.
Formally, one can replace the real time variable t by it, and this can be justified in some settings as "Wick rotation". Moreover, the variable which you are regarding as "time", in the theta function, is the modular parameter, which takes its values in the upper half of the complex plane. It can be purely imaginary, but it cannot be real.
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The dynamical fundamental equations (Newton, Lagrangian and Hamiltonian mechanics, Maxwell's equations, Schrodinger equation) are the energy conservation equations, and correspond to the first law of thermodynamics. Time reversal invariant is the basic symmetry of these equations, it is usually considered as a criterion for reversibility: T-symmetry means reversible.
However, the first law of thermodynamics is also time reversal invariant, and irreversibility is the conclusion of the second law, not that of the first law, such that T-symmetry of the first law cannot be a criterion for irreversibility of the second law.
Similar to that we cannot derive irreversibility from the first law of thermodynamics, in my opinion, “the fundamental structure of theoretical physics might be divided into the two main lines according to different laws, one being the first law physics, the other one being the second law physics”[1]. The conservation equations (CPT-symmetry) correspond to the first law physics, and irreversibility corresponds to the second law physics. T-symmetry of the conservation equations (the first law physics) cannot be considered as a criterion for irreversibility of the second law (physics). It is the symmetry of the equations, we are not sure if it is also the symmetry of the dynamic phenomena themselves.
Then how do we prove the conclusion that the fundamental dynamic processes are reversible?
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Dear Charles, Thanks very much.
"I speak of perfection, but I understand that man maybe not capable of that state."