Science topics: Mathematics

Science topic

# Mathematics - Science topic

Mathematics, Pure and Applied Math

Questions related to Mathematics

Hallo,

there is a new proof of the 3n+1-Problem !

The paper ist available

Perhaps there is a flaw in the proof

What is your opinon?

The Collatz-conjecture (the famous 3n+1-problem):

we construct a sequence of integers starting with integer n = a_0

If a_j is even, the next number ist a_(j+1) = a_j/2.

If a_j is odd, the next number ist a_(j+1) = 3*a_j+1.

Example n = 6:

6, 3, 10, 5, 16, 8, 4, 2, 1

The Collatz-conjecture: the sequence with a every positive starting-integer ends always in the sequence 4,2 1

I want to construct a model for the world COVID-19 data

Matlab based ANN toolbox provides to platform to simulate the following relationship using different algorithms (LM, SCG and so on)

**Y**predicted = function(

**X**i) (1)

Then, a plot of

**Y**predicted to**Y**observed to validate the ANN work.However, is there a way to obtain the mathematical function behind on the above relationship (1)? I know, it has to be highly complex and non-linear function. But is there any specific way to get that function?

I want to correlate real time application to I newly defined Topology that named Tiny Topology.

Dear Sirs,

I think many knows the ideas due to Jules Henri Poincaré that the physics laws can be formally rewriten as a space-time curvature or as new geometry solely without forces. It is because the physics laws and geometry laws only together are verified in the experiment. So we can arbitrary choose the one of them.

Do you know any works, researchers who realized this idea. I understand that it is just fantasy as it is not proved in the experiment for all forces excepting gravitation.

Do you know works where three Newtons laws are rewritten as just space-time curvature or 5D space curvature or the like without FORCES. Kaluzi-Klein theory is only about electricity.

I realized that students do not understand integral conceptually.

We would like to follow the progress in students’ learning through the development of their mathematical skills and are looking thus for an appropriate classification of learners related to their achievements.

Perhaps one of the hardest subjects in distance education applications is mathematics courses. If we dont have an IPAD everthing is very hard. Do you have suggestions for online question solving platforms that I can use in Distance Education Courses?

Dear all :

I

**need to solve the following integral**(attached as an image file)The context is on the calculation of View Factors in Radiation Heat Transfer

I worked out the this expression from the general formula, working out my configuration of two bodies in cylindrical coordinates (for one of the bodies) and using spherical coordinates (for the other body).

But I'm not sure if I ended with a well defined Integral, since I used two different coordinated systems on a same problem.

I used Cylindrical Coordinates for one of the dA and Spherical Coordinates for the other dA, however both dA are part of the same integral.

Hopefully someone out there can give me some help !

Regards and Thank you !

I am interested in collaborating with any researcher working on modelling corona virus using fractional derivatives. If you are a researcher or you have a related project, please feel free to let me know if you need someone to collaborate with you on this research study. If you know someone else working on this research project, please share my collaboration interest with him.her. I would be very happy to collaborate on this research project with other researchers worldwide.

Hi. I'm currently working on my masters' thesis. I will analyse Grade 2 and 3rd (elementary level) maths textbooks and teachers' guides to discover how teaching and learning materials promote students conceptual understanding in mathematics especially the area of number and place value concepts. This will be completely desk-based research.

In order to analyse the materials, Should I use someone's framework or is it okay that I create some kinda criteria on my own to judge. I'd prefer make my own, but I'm not sure I can do that or not.

I would be very appropriated if you could give me an advice.

Distribution dominates policy. Resources are injected at a point and distribute across communities. Can the distribution be almost instantaneous as in the heat equation? Do the resources morph and distribute, drawing in the wave equation? Where is stability (cf. Laplace equation)? These seem basic questions of public policy. Yet, the big three rarely feature in scholarship on public policy. Why?

I would like to fit a curve of my steady-state anisotropy results in Origin, which revealed weak binding between two proteins. I tried quadratic equation but it turned out that it is used for strong interction, so I would like to reevaluate my results. I tried to find information about weak binding fits, but could not find detailed infos.

Thank you in advance!

Hello, I am a beginner in PARAFAC, and I am following Murphy et al. (2013) and using “drEEM” toolbox to process my data. However, I came up against some questions while dealing with the data and applying the method, and I really hope that I can get some advice from here! Thanks!

- I am running RANDINITANAL to obtain the least-square model, but it seems like there are two components in my dataset often appear together, and PARAFAC don’t always decompose(?) them into separate components. The output of 100-run RANDINITANAL for 6 and 7-component model shows that there is a chance of 69% and 91% that PARAFAC will treat them as individual components. However, the runs that didn’t decompose them nearly always have smaller SSEs, though the relative difference in SSE is only about 1%, and will be chosen as the least-square model. I’ve read about that “There is no way to say, from the decomposition whether component one is rightfully the first, second or fifth component.” from the online PARAFAC tutorial “Interactive introduction to multi-way analysis in MATLAB (Bro, 1998)”. What about the difficulty(?) for PARAFAC to resolve a particular combination of components during the random process? And is it normal for PARAFAC to resolve a combination of components more easily(?) but with higher SSE? Should I just simply use the output “LSmodel” from RANDINITANAL?
- Some low-signal samples are included in my dataset, and the contours of the corrected EEMs, especially those with low signal, seem very fragmental. I think this is the reason why I am getting some abruptly-changing excitation and emission spectra. And I think these abruptly-changing spectra are also making my model extremely difficult to validate in split-half analysis. Since I can’t really distinguish the true fluorescence signal from the noise (blank subtraction is done in FDOMCORRECT), removing faulty parts using ZAP or SUBDATASET might not be suitable. I’ve been thinking about smoothing my dataset, however, the instructions of function EEM_SMOOTH in the R package “staRdom” mentioned that smoothing is not advised in PARAFAC analysis. I’m wondering are there any other options when processing these kind of low-signal samples?
- I’ve read about that the score (concentration) and loadings (spectra) of a component are “only determined up to a scaling (Andersen and Bro, 2003)”, for example, multiplying the excitation spectra by 2 and dividing the emission spectra by 2 at the same time doesn’t change the contribution to the model. What about the relative magnitudes between components? Do the relative magnitudes between components have any mathematical (or physical, or chemical, perhaps?) interpretation? I am asking this because those abruptly-changing spectra mentioned above sometimes feature peaks (or spikes) that have greater value than the spectra of other normal-looking components.

If any further explanation for my questions is needed, please let me know. If any of my questions is too basic, or there is any literature I need to read before continuing, please let me know, too.

Thanks for reading and I really appreciate your time!

is there any criteria for evaluation or content analysis in early childhood's mathematics textbook?

I have been receiving complaints from different universities in Germany that master students from countries like India, Nepal, Pakistan can't cope up with the standard of mathematics and the majority of students struggling to pass such courses. Since the Indian Engineering colleges/ universities are divided into IITs, NITs, Government colleges, Private Engineering colleges and so on..the differences in the quality of education are so high that it is difficult for foreign universities to define the qualification criteria in an admission process. Eg. The grades of such students look pretty good on a marks sheet but students' performance in maths exam at German University/FH is poor. Are there any criteria to decide the potential of students during the admission process? Any recommendations to tackle this problem? How other universities in Germany addressing this issue?

DIfferent Mathematical Techniques are being used for regionalization. For example in different references, the authors regionalize the area across the country under different climates.

I know quantum computers have solved problems that would take an

*exponential*amount of time on classical computers. But have they solved a problem that would take an*infinite*amount of time on a classical computer?If this has happened, did it employ quantum indeterminacy?

If this hasn't happened, is there a proof that it can't happen?

I am working on parental beliefs about mathematics and it teaching and learning and want to investigate, in which ways parents support their children with their mathematics education. Therein I am focusing on early secondary school (11-12 year old students).

I am writing a paper assessing unidimensionality of multiple-choice mathematics test items. The scoring of the test was based on right or wrong answers which imply that the set of data are in nominal scale. Some earlier research studies that have consulted used exploratory factor analysis, but with the little experience in data management, I think factor analysis may not work. This unidimensionality is one of the assumptions of dichotomously scored items in IRT. Please sirs/mas, I need professional guidance, if possible the software and the manual.

As applied to physics, the source is a mathematically described process and the target is one without a mathematically described process or without a mathematically described process known to the student. Analogy can suggest a mathematical model to a researcher. Analogy assists the student by demonstrating that knowledge already acquired can help in understanding a new subject. Thus analogy can be an investigative tool and a pedagogical tool. John Holland in his book on Emergence from Chaos to Order attributes the source-target characterization to Maxwell (p. 210) but I have not been able thus far to locate Maxwell’s employment of that characterization. Maxwell spoke about analogy as a useful pedagogical tool in an 1870 address to the Mathematical and Physical Sections of the British Association included in his collective works, volume 2, page 215. At page 219: Analogy `is not only convenient for teaching science in a pleasant and easy manner, but the recognition of the formal analogy between the two systems of ideas leads to a knowledge of both, more profound than could be obtained by studying each system separately.’

Do you know the origin of the source-target analogy?

Dear researchers,

Regarding assumptions of linear regression, can I replace scatter plots with mathematical equations in my article and claim that there is a linear relationship between two variables on the basis of equations. I want to conserve space in my article without presenting scatter plots. Please advise. Thank you.

Review Article in spoecific, Research area Potential Theory

As a founder of making dialectical logic mathematically, author has constructed a mathematical expression for dialectical logic, and proofed the formal logic is only a special case in dialectical logic, see preprint titiled "mathematical foundation for dialectical logic" in my profile, then do you admit author's viewpoints in this field?

I am currently for maths project creating a card game that focusses to improve subitizing for students' age between 6-9 years old. I now want to create the 'best' colors for the game but I am looking for research that shows the effect of colors toward children.

**If you could help me or link me to research I'd highly appreciate it.**

PhotoMath is a new application for solving math problems by capturing their images. Do you think it will be also useful for solving math proofs? What do you think?

Generally QSR is considered as the parameter for location based service. End-to-end delay, number of hops etc. are the parameters for routing. Why combination of routing and location service enhances the performances of the parameters?

a transport model (e.g logit model or ...) is based on statistical data and field works or merely based on mathematical theories or both of them?

If I want to define a model ( e.g. a new model in freight transportation ), what actions should I do? what kinds of data should I gather?

I am trying to justify the use of AT instead of UTAUT for my paper on teacher challenges faced when using technology to teach mathematics...

While many modern causal models do not seem to adhere to Laplace's demon (strict determinism) which treated error factors as merely unknown causes, they do not also always address the issue of freedom and responsibility sufficiently. While it is acknowledged that the human element (as far as intervention) is concerned might involve an exogenous factor (perhaps, "transcendent cause" in neoplatonic terms), posing problem to the equilibrium of an otherwise deterministic system, the models themselves might seem relevant for systems that are independent of human intervention, e.g. artificial intelligence. But, that evokes ethical questions, especially regarding whether formalism of such models can totally ignore the question of responsibility or should they really be resolving them. In more practical terms, can such a machine be constructed based on a causal model that can correctly predict and make right moral decisions for humans?

To me it is mostly a story.

There is, at the outset, a puzzle about some natural phenomena, perhaps encountered by inadvertence.

Then some other process exhibits a similar pattern. The question becomes is there some reason, perhaps based on the thermodynamics of the two systems, that connects them?

This takes the curious inquirer into a conceptual forest, or overgrown garden, path obscured, looking for a common principle. When a principle is discerned, there are more questions.

Does the pattern appear elsewhere?

Is there a more fundamental principle underlying the first principle discerned?

Does a principle, even more fundamental, connect all the different phenomena sharing a kind of pattern? Does the same pattern appear but in subtle ways in other phenomena?

Can the phenomena be modeled? What assumptions are extraneous to arriving a model in common? What is the set of minimal assumptions?

Many more paths and tangles appear.

Can the winding path so obscure at the outset be reduced to a set of logical statements that resemble in their appearance mathematical deduction? Never finally, but at least provisionally?

But first, there is a story.

How do you regard physics?

In the litterature about quantization schemes, people tend to use Weyl ordering a lot.

Altough it enjoys some desirable properties like sending real functions into self-adjoint operators or sending Schwarz functions into trace class operators, we know that these features are not unique of Weyl ordering.

Is there any deep reason (being mathematical of physical) to prefer Weyl ordered quantizers?

Hi,

I'm attempting to create nonlinear metamaterial structures in comsol and I don't know how to measure second harmonic generation.

How do I measure that frequency x goes into structure and generates frequency 2x ?

Thanks for any help.

Why many scientists use the term mathematical model ?

If you have a certain phenomenon and you want to model it, you will describe its, more or less, approximate behaviour by applying to it laws which can be physical, chemical, economical, geometrical and so on, depending on the phenomenon.

Mathematics is only a tool to describe these laws, so you should speak of physical, chemical, economical, geometrical ... models and not of mathematical ones.

Most of the models I encounter in my research are physical models because, to build them up, the laws of physics are used.

Each time I hear the term mathematical model, my nose gets wrinkled.

What is your opinion ?

What is the mathematics behind r.viewshed module in GRASS GIS

I want to conduct a qualitative research about math teaching and learning at pandemic Covid-19 in several specific area in my country. But i don't have any idea to start because i'm not good in qualitative research. It's kindly opened for join research.

Saya ingin melakukan penelitian kualitatif ttg KBM Matematika selama wabah Covid-19 di beberapa daerah di Indonesia. Tapi saya bingung dalam merancangnya krn minim pengalaman dalam penelitian kualitatif. Sangat terbuka untuk penelitian bersama.

Dear sir/madam!

I'm a final semester student in BS Mathematics and my research interest is in Mathematical Biology. Would you like to provide me the best SEIQR ODEs model for stability and optimal control? I want to do stability and optimal control for our province's real data. So, please recommend the paper.

Thank you so much.

Is there any alternative topic/theory/mathematical foundation to compressed sensing (CS) theory?

successive to Nyquist Criterion is CS theory, is there any theory that surpasses the CS theory ?

What does it actually mean to exist? How is it different from non-existence? How can we be sure if something exists or does not exist? I have made a case that these questions are more fundamental than the usually dubbed first question "Why is there something rather than nothing"? Here is a ready link for which I would appreciate your comments.

Please do feel free to share the link with your colleagues and friends who you think might be interested in this topic.

I want to create an animation to insert it in my math presentation (e.g. a ball hitting the wall, deforming and bouncing back: just an example). Is there any free and easy to use software (preferably, for Mac OS X) to do that?

Which one is the best? I know how to create some animations in Matlab and Mathematica, but this is different: I don't want to code the whole scene as functions.

I wish to shift multiple lines or curves (up to 25 lines/curves) so that they are superimposed on one another. This is to enable me see clearly the points or regions where any one of the curves deviate from the others. In this procedure I also want to be able to vary or determine the region or range of superimposition or overlay of the curves. What mathematical function or formulae can enable me do that?

I have a derived block formulae and I want to use it to solve second order system of equations using maple. So, I need a sample of maple code which will serve as guide for me

I couldn't see any options to show complete axes of 3D plot in MATLAB software ?

There is option to tick Box. But it doesn't covers top axes in

Its a book related to biostatistics.

Have any mathematical relation for all kind of materials?

The Riemann zeta function or Euler–Riemann zeta hypothesis is the more challenging and unsolved problem in mathematics. What's the applications in physics and science engineering ? Some research advances to solve it ?

Hi everyone,

I currently use MCS method to analyze effect of some uncertain parameters on electrical power system and run 10,000 simulations to calculate the output which approximately takes around 1 hour.

I recently read some methods which can reduce the MCS scenarios thus, resulting in low computational time.

So, can our fellow researchers elaborate more on this topic or suggest me any other techniques which has the potential to significantly reduce the computational time of MCS (say around 5 minutes for my work) with reasonable accuracy?

Cheers

Sam

Can someone explain and give me a precise mathematical definition of what "variance" means in terms of principal component analysis (PCA)?

I have been looking at different types of inductive teaching for mathematics. These include inquiry-based, discovery, problem-based, project-based, case-based, just-in-time, and a hybrid of project and problem-based.

Is there an inductive teaching approach or curriculum that uses everyday topics and students learn the mathematics needed to understand different pieces of it? For example, a class is discussing gardening. So the students learn how to calculate area of their garden. Then they look at mixture problems (fertilizer and soil). Then they see how Fibonacci plays into petals and seed patterns.

It doesn't quite fit one of the inductive teachings exactly. I think it is a combination of several.

Who has done research on this? Who/what should I be looking for?

I need a book, chapter or something like that which discusses PV inverters.

It explains

**Mathematical relationships**and finally**Simulates**it.**Call for Papers & Submissions**

The 9th International Eurasian Conference on Mathematical Sciences and Applications (IECMSA-2020) will be held on

**August 25-28, 2020 in Skopje, North Macedonia**. IECMSA-2020 will be organized in cooperation with International Balkan University.The annual International Eurasian Conference on Mathematical Sciences and Applications (IECMSA) series aim to promote, encourage, and bring together researchers in the different fields of Mathematics by providing a forum for the academic exchange of ideas and recent research works, The previous conferences were held as follows: IECMSA-2012, Prishtine, Kosovo, IECMSA-2013, Sarajevo, Bosnia and Herzegovina, IECMSA-2014, Vienna, Austria, IECMSA-2015, Athens, Greece, IECMSA-2016, Belgrade, Serbia, IECMSA-2017, Budapest, Hungary, IECMSA-2018, Kyiv, Ukraine, and IECMSA-2019, Baku, Azerbaijan.

Website: www.iecmsa.org

**IMPORTANT DATES**

Deadline for Early Registration: May 22, 2020

Deadline for Hotel Reservation: May 22, 2020

Deadline for Registration: July 17, 2020

Deadline for Abstract Submission: July 17, 2020

How can I get an endorsement for my mathematical archive in the arXiv website?

how can i contact sir wayne w. Welch? I want to ask permission if i can use and guide how to use the Mathematics attitude inventory?

Hello,

I'm currently working on a Structural Health monitoring approach for the foundations of an offshore wind turbine based on its resonance frequencies. On the basis of a large dataset that recovers measurements of several independent variables , I have already established a linear model in order to predict the target (here, the resonance frequency). I performed a Dominance analysis, Regressions, Features selection etc., in order to evaluate which features influences my target the most. However, I would like to improve the accuracy of my linear model by adding more features to my dataset (and then select the best features to build the most suitable model.), i.e. identify underlying mathematical expression (non-linear) between the independent variables and the target. I already performed Genetic Programming (GP) with symbolic regression (SymbolicRegressor) but didn't get consistent results. Is there a method by which I could get these underlying (non-linear) mathematical relationships ?

Thanks a lot,

Lolo_jr

Can you help me interpret the result of of the ATMI different factors..how can i interpret it as how low, moderate, or very high the result is of the factors.

Dear ResaerchGate Members,

I would like to check the observability and controlability of a system that has 200 states. When I use the conventional method ofobservability based rank, the Matrix of A^(n-1) (A^199 , where A has 200x200 arrays) will have the array of infinity.

I would be thankful to have your recommendations?

Best regards, Reza

#Observability ; #Controlability ; #Control

My institution(where I work), Accra Institute of Technology(AIT) is switching to Open-Book Exams Questions for our mid-sem exams. A little challenge is with the applied mathematics courses and how the students will submit their responses in MS Word format. Hence this inquiry. Attached is a sample question.

Movement in musical scores does not have an equation of motion or a calculus of variations.

Is there any other kind of harmonic motion that does not obey Newtonian law?

Of course, frequency is velocity-like but I do not see this in the literature.

I understand that the force field may be uniform so dF = 0, but is it not true there must be a force if movement occurs.

It is the requirement of one project of location of the dams and rivers in the country.

It is required in the designing of instrument.

basically scholar is having maths and statistics background but he is doing research in fluid mechanics. he is interested but difficulty is finding problem and doing paper publications.

so we need some suggestions. how to develop knowledge on this research area being a mathematics scholar.

when using this [peaksnr,snr]=psnr(watermarked_rgb,host); value is 44.13 and 38.39 but when using
MSE=mse(watermarked_rgb,host); value is 0.2456,0.2146 and 0.2691 respectively. If you use the mathematical equation PSNR = 10log10(255*255/MSE) values came 54.So which one is correct.

I am looking for simple text book references to understand the mathematics used by Ashtekar in papers like Asymptotic with positive cosmological constant. I understands GTR so far as Einstein equation and its solution like Schwartzchild solution, kerr etc. There is a great bandgap in mathematics used by these two scenarios.

Study the history of mathematics. Likely, it will start at Mesopotamia 3000 BC. Now, it is undisputed H. sapiens trace back to Africa, perhaps earlier than 200 millennia ago. So, didn’t the early humans think about themselves and the environment around them? Of course they did. And they used tools of mathematics. Nearly 60 years ago, that mathematics was discovered in Ishango, the border between Uganda and the DRC. So, why does mathematics ignore Ishango?

Would you like to read (look through) this book?

Research Proposal MATHEMATICAL NOTES ON THE NATURE OF THINGS

By the way, book publishing shy away from such a proposal, so along the way I wanted to ask our community for advice.

List of journals pure and applied mathematics

Impact factor in Scopus or Thomson. Only journals requesting author reviewers

In the literature, fractal derivatives provide many physical insights and geometrical interpretations, but I am wondering where we can apply this particular derivative appropriately. Please refer me to references or examples because I am very interested to learn more about new derivatives and their applications!! I greatly appreciate all the brilliant efforts in this discussion!!

How the imaginary part of the refractive index or the extinction co-efficient glycerol or ethanol changes with the glycerol or ethanol concentration in an aqueous solution?

Is there any mathematical expression to calculate the change in the imaginary part of the refractive index of glycerol or ethanol with its concentration ?

The

**the amount of data received by the user in a unit of time. How can I write this in a mathematical equation?***Throughput is*The paper titled by "Closed-form formula of Riemann zeta function and eta function for all non-zero given complex numbers via sums of powers of complex functions to disprove Riemann hypothesis" disproves the well known unsolved mathematics problem, Riemann hypothesis. Thank you for your time and consideration. The full paper is available here:

The substrate is in a rectangular shape, the length is 7,6 cm and width is 2.86 cm.

The particle density is 1.2, the volume of the particles is 50nm and the PH value is 2 and the amount of the particles in volume used to coat is 1000 microliters.

Hello dear friends

For my thesis work, I need to first grade students in mathematics achievement test.

Please, any of you can help with this.

Thank you forever for your kindness

While most governments try to hide the facts and manipulate statistics about COVOD-19 due to political/economical/stupidity reasons, many physicians and scientists are currently working on finding cures for COVOD-19. I am curious whether there is any center/platform to use experts from different areas of research in this fight.

To be clearer, let me ask this:

I work in biomedical engineering department. I, my colleagues and our students are familiar with optimization, data analysis, artificial intelligence, time-series analysis, modeling, control and …

I hope there might be a center which can provide some data, plus some tasks, so we can do some real and useful research and have a share in this fight.

Just a saying: maybe a proper deep neural network can suggest best combination of drugs according to the available history.

-----------------------

P.S.

My question is about the direct fight. I don’t mean helping in e.g. producing masks, cloths and …

How to validate mathematical equations which govern a process/ phenomenon?

I have few mathematical models which govern a mechanical phenomenon..Experimentation is not possible..hence I want to do the validation.