Selecting particular columns from large datasets (csv) using R Studio?

So I have large number of csv files (100+) in a directory with same structure and column names. The data is in time series and there are approx 30 columns/file. However i only want to aggregate...

08 February 2021 245 5 View

How can solve the second order linear homogeneous partial differential equation with variable coefficients?

can someone help me with reduced the partial differential equation du/dt = - f(x) d^2 u/ dx^2 - g(x) du/dx --- (1) to become: du/dt = - p(x) d^2 u/ dx^2...

21 January 2021 3,296 1 View

IHC-paraffin experiment: how do you approach shopping for an antibody?

Hello everyone! I am shopping for an arginase 1 antibody to use for IHC-paraffin experiments with rat tissue. So far what I have understood is that if an antibody says it is reactive with rat,...

16 January 2021 794 3 View

How much pre-PCR dilution of mixed-template DNA extracted from pollen (honey) is appropriate for Metabarcoding?

I'm working on pollen DNA metabarcoding to identify the floral composition of honey. How much pre-PCR dilution of mixed-template DNA extracted from pollen (honey) is appropriate for the...

28 December 2020 9,132 1 View

How to add two vertical and parallel Fresnel reflection coefficients to retrieve overall reflection coefficient for a right hand circular wave?

I have a problem in which a right hand circular polarized wave (GPS wave) encounters an ideal smooth plane obliquely, and then is reflected off that. To solve this kind of problems, the wave is...

28 December 2020 2,271 3 View

Which is better to focus on teaching or research for a good academic life and Why?

Which is better to focus on teaching or research for For a good academic life and Why?

26 December 2020 5,737 9 View

Is ag paste suitable for back contact on silicon wafer? or i should deposit al on the back surface using pvd or plasma sputtering?

Fabricating silicon solar cell

22 December 2020 4,906 7 View

Which renewable source is the best ?

wind hydro solar etc.

21 December 2020 6,360 16 View

Why is light pure energy?

light is pure because the light is the simplest electromagnetic construct but the energy of any object is also of the same kind.

20 December 2020 207 4 View

How to explain insignificant independent variable which is significant with interacting (Moderation) variable?

10 December 2020 3,037 1 View

After a reference from Int J Body Compos Res, can any body help?

Hi, I am after the reference below, my library says it cannot obtain a copy either locally or internationally, any help appreciated! Chris Wang ZM, Heshka S, Wielopolski L, Pi-Sunyer FX, Pierson...

03 March 2021 6,193 1 View

Irradiation data for JAPAN?

Hi, Could you help me to get the latest (2019, 2020) solar resource data for a particular site in JAPAN? PV GIS and NSRDB data are not in reach to JAPAN, I'm looking for some other database for...

03 March 2021 961 3 View

I need to image mesoporous silica nanoparticles that are in ~100 nm size and do high resolution TEM to look at mesopores. what grids should I use?

Need to image mesoporous silica nanoparticles using the TEM. Also, need high resolution TEM images to see the mesoporous structure. Kindly suggest what kind of grids to use. Thanks, Shatadru

02 March 2021 1,787 2 View

Why are the velocities so high in my Boussinesq approximation Fluent simulation?

Hello, I have a mechanism where air rises due to convective flows. In this simulation, nothing is driving the air except this. I understand that the Boussinesq approximation only works for small...

02 March 2021 4,910 3 View

Help request in CST microwave?

im working now on TPV solar cells and metamaterials and i realy need our help in CST microwave i have a tpv cell simulation and i want to extract particullarly the absorbtion of only the active...

02 March 2021 2,246 2 View

Anyone found any research papers on solar furnace design calculations (for solar concentration)?

I am thinking about working on solar furnace with heliostats that concentrate sunlight and heat molten salt, but currently no luck with research. Not a lot of papers based on the subject. (check...

01 March 2021 5,023 5 View

How to size battery banks?

I am designing a small grid connected solar PV power-plant. As the battery's capacity is specified in Ah and demand in kWh. What is the best way to size the battery bank? I have battery price in...

28 February 2021 1,638 3 View

How to design a boost converter for a mppt controller?

I have a doubt on how to select the inductor and capacitor value when I want to implement MPPT controller. This is because we always take a maximum output voltage and current but in this case, we...

28 February 2021 3,637 2 View

How to calculate Ligand-active site distance in a ligand-protein complex from MD simulation?

I have run a MD simulation of a ligand-protein complex in GROMACS using CHARMM forcefield. Reviewer has asked me to calculate Ligand-activesite distance and binding free energy of ligand with...

27 February 2021 4,703 1 View

High aspect ratio hexahedral mesh optimization solver?

I am interested in evaluating mesh optimization solvers that converge to high aspect ratio unstructured hexahedral grids. In other words, I am interested in a solver that optimizes warpage,...

26 February 2021 7,279 2 View