Why is the matrix P positive definite?

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How to make overlapping p-h diagram in EES?

I want to draw ph diagram using Engineering equation solver EES for refrigerant R134a and R1234fy and some other. I don't know how to draw the multiple ph diagram on same dome or overlapping to...

30 July 2024 647 7 View

What binder would be the best choice to modify glassy carbon electrode with a 2D Material like Graphene or MXene?

I am trying to drop cast 2D Materials on Glassy Carbon Electrode for Cyclic voltametry and EIS purpose. What would be best binders to use?

23 July 2024 5,776 2 View

How to display grain boundaries in RVE model?

Many literatures have shown that the RVE model shows the grain boundaries between different grains. How can this be achieved using DAMASK+paraview?

21 July 2024 9,224 1 View

Abnormal data in in-vitro drug release study?

I'm doing in-vitro drug release study using dialysis bag method and collecting samples from the external medium at several time points, subjecting to UV-Vis spectrophotometry. But my absorbance...

14 July 2024 6,829 2 View

Are my cells contaminated with mycoplasma?

I suspect my cells are contaminated with mycoplasma. I fixed the cells with 4% PFA and stained them with DAPI. Below is the image I obtained. I don't observe the typical small, rounded DAPI foci...

11 July 2024 7,786 3 View

Black dots like contamination in my cell cultures. What are they?

There are black dots that seem like contamination in my corneal endothelial cell cultures. Some of the cells appear unhealthy and are enlarged. The black dots are more prevalent around these...

11 July 2024 4,829 0 View

What is the most simple language and character in the world?

Dear colleagues, As well known, we can deliver messages in different languages and characters, including Chinese, English, Latin, binary and decimal codes (if with a converter) and many other...

08 July 2024 5,422 13 View

Trouble shooting on mediation with survival regression and linear regression?

I did linear regression of X (independent variable) to M (Mediator) then I used survival regression to fit X to Y (dependent variable) With these questions: a. HOW to correctly do a mediation...

17 June 2024 1,478 6 View

Potato handbook crop of the future--PDF?

Whoever has an electronic version of this book, sell it to me，《potato handbook crop of the future》Thanks

15 June 2024 4,404 0 View

Why is the blue and white spot screen negative for all white spots?

The protein was expressed using the insect cell system, and the recombinant plasmid was successfully constructed as verified by sequencing, and the recombinant plasmid was transformed into DH10...

13 June 2024 2,590 4 View

How to define an anisotropic material with asymmetric elastic compliance/stiffness matrix in ANSYS APDL?

I need to model an anisotropic material in which the Poisson's ratio ν_12 ≠ ν_21 and so on. Therefore, the elastic compliance matrix wouldn't be a symmetric one. In ANSYS APDL, for TB,ANEL...

09 August 2024 5,048 2 View

Is it true that $\det(V(A))$ may be only $\pm 1$, depending on $n$, for the last symmetric tridiagonal matrix $A$?

One can try to generalize the Vandermonde determinant in the following direction: Let $A$ be any symmetric $n$-order square matrix. Consider its powers' diagonal elements $(A^k)_{ii}$ and...

08 August 2024 6,690 1 View

Usage of internal standards in LC-MS/MS analysis?

Have you ever seen a LC-MS/MS method uses both internal standards and external standards (in matrix matching purpose) but the concentrations of internal standards are outside the calibration curve...

05 August 2024 3,084 6 View

Request a single Lecture notes for math as detailed as this that I can find in one place?

- The Existence/Uniqueness of Solutions to Higher Order Linear Differential Equations - Higher Order Homogenous Differential Equations - Wronskian Determinants of $n$ Functions - Wronskian...

03 August 2024 2,366 0 View

Tissue homogenization in mouse with FastPrep-24™ 5G - is the D matrix system useful?

I need to lyse and homogenise mouse tissues. So far I have experimented with liver and lung tissue, using matrix D. The liver was completely lysed with 6 repetitions of the standard program, but...

31 July 2024 9,186 0 View

Is it true that science is leaving the era of mathematics and entering the era of matrix mechanics?

We assume this to be true. Science leaves the era of mathematics and enters the era of matrix mechanics and the turning point is the discovery of numerical statistical theory called Cairo...

31 July 2024 3,900 2 View

Help on understanding the implementation of Mori Tanaka method on MATLAB?

I am new to Micromechanics and having similar problem with understanding the implementation of the formula's. I would appreciate if anyone can guide me on how to go about getting a scalar value...

30 July 2024 969 0 View

How Can I Apply Hashin Damage Properties to Solid Elements in Abaqus Without Using VUMAT?

Sure, here is the translation: I have a 3D orthogonal woven composite structure where warp, weft, and binder yarns are oriented in three directions. After modeling these yarns and the matrix in...

28 July 2024 8,169 0 View

Can we find a statistical matrix mechanics equivalent to the Schrödinger equation?

We assume that we can find a statistical matrix mechanics equivalent to Schrödinger's PDE in two consecutive steps: i-Transform the Schrödinger PDE describing the wave function Ψ into its square...

27 July 2024 3,959 4 View

Can biogeographical regions work as a character in a character matrix for a phylogenetic analysis?

Basically I'm helping with the matrix using a cosmolitan group, could one of the characters used for be biogeographical regions (Neartic, Neotropical, etc)? Most of the data in this matrix refers...

25 July 2024 9,753 2 View