Watershed Hydrology: Geomorphological Snowmelt-Runoff Modeling (SRM Mechanics)

 In high-altitude alpine catchments, seasonal snowmelt dominates streamflow regimes. The Snowmelt-Runoff Model (SRM) quantifies daily runoff $(Q_{n+1})$ generated from snow cover depletion and liquid precipitation using a degree-day approach: $Q_{n+1} = \left[ c_{Sn} \cdot a_n \cdot (T_n + \Delta T_n) \cdot S_n + c_{Rn} \cdot P_n \right] \cdot \frac{A \cdot 10000}{86400} \cdot (1 - k_{n+1}) + Q_n \cdot k_{n+1}$ ​Where: ​$c_{Sn}, c_{Rn}:$ Runoff coefficients for snow cover and rain. ​$a_n:$ Degree-day factor $(\text{cm/}^\circ\text{C}\cdot\text{day}).$ ​$T_n:$ Adjusted daily mean temperature $(^\circ\text{C}).$ ​$S_n:$ Snow cover area fraction derived from remote sensing. ​$P_n:$ Measured precipitation $(\text{cm}).$ ​$A:$ Catchment zone area $(\text{km}^2).$ ​$k_{n+1}:$ Recession coefficient $(k = Q_{n+1} / Q_n).$ ​Run-of-the-river hydroelectric stations operating across Himalayan river basins (such as the Chenab, Sutlej, and Bhagirathi) rely heavily on snowmelt and glacier runoff ...
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Strength of materials...one liners...

Strength of materials

 One liners............

  1. Ratio of change in dimension to original dimension know as strain.
  2. Strain has no dimension and it is fundamental behaviour of materials.
  3. Strain is fundamental quantity because it is measured in the laboratory.
  4. Strain at right angle to the direction of the applied load called lateral strain.
  5. S.I. unit of force is Newton (N).
  6. Volumetric strain is three times linear strain.
  7. Deformation progressively with time called creep.
  8. The property by which the body returns to its original position after removing load is known as ELASTICITY.
  9. Property by which the body can be beaten or rolled into thin plates called Malleability.
  10. Hooke's Law valid within elastic limit, Hence called elasticity law also.
  11.  Same optical properties like permittivity, permeability in all direction called isotropic.
  12. same elastic properties in all direction called Homogeneous material.
  13. Plastic does not regain its original position after removing load.
  14.  After elastic limit tensile strain increases more rapidly.
  15. The hyper elastic materials are derived from a strain energy density function.
  16. Modulus of elasticity measures object’s resistance to being deformed elastically.
  17. Ratio of stress to strain is elastic modulus.
  18. Hook’s Law states stress proportional to the strain within elastic limit .
  19. For isotropic, homogeneous and elastic material obeying Hooke's law, the numbers of independent elastic constant is 3. (E,G,K)
  20. Ultimate stress to permissible stress called factor of Safety (FOS).
  21. Hooke’s law for 1D is for normal stress and strain.
  22. Limit off proportionality not depends on material/Loading type, It's depend on area of cross section. 
  23. Steel, Aluminium, Copper are hookean materials.
  24. Highest value of stress for which Hooke's Law valid called proportional limit.
  25. Slop of stress-strain curve or flow curve in the elastic deformation region is elastic modulus.
  26. At lower yield point plastic deformation begin.
  27. Area between ultimate point and rupture point is necking region.
  28. The property by which material can be drawn into thin wires is ductility, because ductile materials can withstand large deformation.
  29. Malleability is the property by which material can be made into thin sheet.
  30. Ductile materials can resist large deformation before absolute failure by rupture.
  31. Creep is gradual increase of plastic strain with the time at constant load.
  32. Orthotropic materials has different elastic properties in perpendicular direction.
  33. E=2G(1+¶)=3K(1-2¶)  where, E=elastic modulus, G=shear modulus, K=bulk modulus, ¶=poison’s ratio.
  34. The points on flow curve comes in given order,
    1. Proportionality limit
    2. Elastic limit
    3. Upper yield point
    4. Lower yield point
    5. Yield plateau
    6. Ultimate point
    7. Breaking point 
  35. True stress strain curve or flow curve is based on the instantaneous dimensions of specimen.

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