T-test and Mann-Whitney U test on groups with different sample sizes and variances?

Hello I have 2 groups with different sample sizes of (experts: 5 to 8) and (Users: 28 to 35) answering 21 questions on a 7 points Likert scale about the importance of some dimensions for...

31 January 2021 3,885 7 View

What are the types of optimization problems that can't be tackled by meta-heuristic and heuristic algorithms?

Any decision-making problem when precisely formulated within the framework of mathematics is posed as an optimization problem. There are so many ways, in fact, I think infinitely many ways one can...

06 September 2020 9,415 14 View

Is it possible to reduce tensile strength and increase compressive strength by adding any admixture to concrete?

Hello, I want to know is it possible that the compressive strength of concrete increase by reducing tensile strength? if yes, how we can explanation and justification this issue?

30 April 2020 4,489 7 View

What are the plans for exams and assessments of universities during corona virus pandemy?

What alternative ways universities use for academic assesment of students?

29 April 2020 3,091 1 View

Is there a specific way to discretize a continuous model to any arbitrary multi DOF system and extract the mode shape matrix in abaqus?

27 April 2020 239 3 View

What is best sampling method for cross sectional studies?

I want to research on liver disease patients behaviours and habits in shiraz city. How can I calculate sample size accurately? Thanks

23 March 2020 9,974 5 View

Anyone in kolkata working of LNCaP prostate cells?

I am working with prostate cancer cells, i want to know who is presently working with PCa cell lines in viro and in vivo in kolkata.any leeds will of great help.

07 March 2020 7,831 1 View

How can I find the IDT point of the following TGA curve which is related to a clay soil?

The attached file shows the TGA curve of a clay soil. Can anyone help me how to recognize the initial decomposition temperature (IDT) from this curve?

06 February 2020 6,944 3 View

How to isolate dorsal root ganglia in rat at lumber region?

For pathological investigation of sensory and motor nerves in lumber region of rat how to isolate and preserve

04 November 2019 8,974 1 View

What's the procedure for validation test of a new design of product (Say Heat Exchanger)?

after 3D design of all components of the Heat Exchanger geometry we do assembly and finalization of the geometry, in CFD analysis we change the boundary conditions and it refers us to the...

27 October 2019 9,095 3 View

Heat exchanger with liquid Nitrogen as coolant?

I want to cool Natural Gas from 195 Kelvin to 138 Klevin in a heat exchanger by using liquid nitrogen as the coolant medium. When entering the heat exchanger, the liquid nitrogen will have a...

01 March 2021 6,450 5 View

Why do a weight decrease for thermal degradation in nitrogen gas condition?

Hi all The question is related to TGA(Thermogravimetric analysis). Thermal degradation easily understood but why do samples weight decrease? altough just binding is broked, the weight of...

26 February 2021 1,100 5 View

Steps to calculate activation energy by coats & redfern method?

I'm a chemistry student and I'm researching the kinetic degradation of mixed plastic waste. I'm having trouble calculating the activation energy by the coats & Redfern method. The data that...

24 February 2021 974 1 View

How to get/count refractive index in gasses?

20 February 2021 8,202 6 View

How much costs direct reduction of nitrogen on farmland in terms of lower crop yield?

Dear research fellows, I wonder if someone knows how much direct reduction of nitrogen on farmland costs in terms of lower crop yield expressed as EUR/kg nitrogen (or similar)? I understand that...

15 February 2021 1,323 3 View

Are there alternatives to the Devarda alloy when estimating nitrogen?

Are there alternatives to the Devarda alloy when estimating nitrogen? devarda alloy is reducing the nitrate to ammonium

15 February 2021 8,838 3 View

What is the optimal method to prepare a controlled porosity osmotic pump (CPOP) tablet for scanning electron microscopy?

In order to assess the shape and size of pores formed by dissolving the pore former in the semipermeable membrane structure, SEM images are needed. Cellulose acetate was used in the coating...

15 February 2021 6,135 3 View

About XRD details of pristine and doped RGO?

Hi Can anyone please help me know the XRD details of reduced graphene oxide, Nitrogen doped reduced graphene oxide, Sulphur doped reduced graphene oxide, Nitrogen and Sulphur co-doped reduced...

08 February 2021 3,033 3 View

How to make Fast Green FCF from powder?

Hi everyone We need Fast Green to electroporate plasmid into mice embryos, therefore we simply need it to see some color in the liquid we are electroporating so that electroporation is more...

07 February 2021 1,671 2 View

Which is the best software for the simulation of tribological properties of materials?

I want to simulate the tribological properties of solids, liquids, and fluids, please suggest good software.

02 February 2021 3,947 3 View