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diff --git a/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/1-Semiconductor_materials_and_crystal_properties.ipynb b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/1-Semiconductor_materials_and_crystal_properties.ipynb
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@@ -0,0 +1,186 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 1: Semiconductor materials and crystal properties"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.3: Calculate_Density_of_Copper_Crystal.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 1.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"r=1.278;//in Angstrum\n",
+"AtomicWeight=63.5;//constant\n",
+"AvogadroNo=6.023*10^23;//constant\n",
+"//For FCC structure a=4*r/sqrt(2)\n",
+"a=4*r*10^-10/sqrt(2);//in meter\n",
+"V=a^3;//in meter^3\n",
+"//mass of one atom = m\n",
+"m=AtomicWeight/AvogadroNo;//in gm\n",
+"m=m/1000;//in Kg\n",
+"n=4;// no. of atoms per unit cell for FCC structure\n",
+"rho=m*n/V;//in Kg/m^3\n",
+"disp(rho,'Density of crystal in Kg/m^3: ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.4: Obtain_volume_density_of_Si_atoms.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 1.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"n=4;// no. of atoms per unit cell of silicon\n",
+"AtomicWeight=28;//constant\n",
+"AvogadroNo=6.021*10^23;//constant\n",
+"m=AtomicWeight/AvogadroNo;//in gm\n",
+"m=m/1000;//in Kg\n",
+"a=5.3;//lattice constant in Angstrum\n",
+"a=a*10^-10;//in meter\n",
+"V=a^3;//in meter^3\n",
+"rho=m*n/V;//in Kg/m^3\n",
+"disp(rho,'Density of silicon crystal in Kg/m^3: ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.5: Calculate_surface_density_of_atoms.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 1.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"a=4.75;//lattice constant in Angstrum\n",
+"a=a*10^-10;//in meter\n",
+"disp('Surface density in FCC on (111)Plane : dp = 2.31/a^2');\n",
+"dp=2.31/a^2;//in atom/m^2\n",
+"dp=dp/10^6;//in atom/mm^2\n",
+"disp(dp,'Surface density in FCC on (111)Plane in atoms/mm^2: ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.6: Determine_Interplanar_Distance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 1.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"lambda=1.539;//in Angstrum\n",
+"theta=22.5;//in degree\n",
+"n=1;//order unitless\n",
+"d=n*lambda/(2*sin(theta*%pi/180));//in Angstrum\n",
+"disp(d,'Interpolar distance in Angstrum : ')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.7: Determine_Wavelength_of_X_rays.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 1.7\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"\n",
+"theta=16.8/2;//in degree\n",
+"n=2;//order unitless\n",
+"d=0.4;//in nm\n",
+"lambda=(2*d*sin(theta*%pi/180))/n;//in Angstrum\n",
+"disp(lambda,'wavelength of X-rays in Angstrum : ');\n",
+"//Note: Ans in the book is not correct"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/2-Energy_Bands_and_Charge_Carriers_in_Semiconductor.ipynb b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/2-Energy_Bands_and_Charge_Carriers_in_Semiconductor.ipynb
new file mode 100644
index 0000000..ce71960
--- /dev/null
+++ b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/2-Energy_Bands_and_Charge_Carriers_in_Semiconductor.ipynb
@@ -0,0 +1,698 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 2: Energy Bands and Charge Carriers in Semiconductor"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.10: Find_conductivity_of_Si.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.10\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ni=1.5*10^10;//in cm^-3\n",
+"e=1.6*10^-19;//in coulamb\n",
+"MUh=450;//in cm^2/V-s\n",
+"MUe=1300;//in cm^2/V-s\n",
+"SIGMAi=ni*e*(MUe+MUh);//in (ohm-cm)^-1\n",
+"disp(SIGMAi,'Conductivity of silicon(intrinsic) in (ohm-cm)^-1 ');\n",
+"Na=10^18;//in cm^-1\n",
+"SIGMAp=e*Na*MUh;//in (ohm-cm)^-1\n",
+"disp(SIGMAp,'Conductivity of resulting P-type si semiconductor in (ohm-cm)^-1 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.11: Find_conductivity_of_intrinsic_Ge.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.11\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ni=2.5*10^13;//in cm^-3\n",
+"e=1.6*10^-19;//in coulamb\n",
+"MUh=1800;//in cm^2/V-s\n",
+"MUe=3800;//in cm^2/V-s\n",
+"SIGMAi=ni*e*(MUe+MUh);//in (ohm-cm)^-1\n",
+"GeAtoms=4.41*10^22;//in cm^-1\n",
+"DonorImpurity=1/10^7;//in per Ge Atom\n",
+"Nd=4.41*10^22*DonorImpurity;//in cm^-1\n",
+"n=Nd;//in cm^-1\n",
+"p=ni^2/Nd;//in cm^-3\n",
+"SIGMAn=e*Nd*MUe;//in (ohm-cm)^-1\n",
+"disp(SIGMAi,'Conductivity of Ge(intrinsic) in (ohm-cm)^-1 ');\n",
+"disp(SIGMAn,'Conductivity of resulting N-type Ge semiconductor in (ohm-cm)^-1 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.12: Find_drift_velocity_of_electron_and_hole_Conductivity_and_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.12\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"MUh=0.18;//in m^2/V-s\n",
+"MUe=0.38;//in m^2/V-s\n",
+"V=10;//in Volts\n",
+"l=25;//in mm\n",
+"w=4;//in mm\n",
+"t=1.5;//in mm\n",
+"E=V/(l*10^-3);//in\n",
+"//part (i)\n",
+"ve=MUe*E;//in m/s\n",
+"vh=MUh*E;//in m/s\n",
+"disp(ve,'Drift velocity for electrons in m/s : ');\n",
+"disp(vh,'Drift velocity for holes in m/s : ');\n",
+"\n",
+"ni=2.5*10^19;//in m^-3\n",
+"//part (ii)\n",
+"SIGMAi=ni*e*(MUe+MUh);//in (ohm-m)^-1\n",
+"disp(SIGMAi,'Conductivity of Ge(intrinsic) in (ohm-m)^-1 ');\n",
+"//part (iii)\n",
+"I=SIGMAi*E*w*10^-3*t*10^-3;//in Ampere\n",
+"disp(I*10^3,'Total current in mili ampere : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.13: Find_diffusion_coefficient_of_electron_and_hole.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.13\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"T=300;//in Kelvin\n",
+"MUh=1700;//in cm^2/V-s\n",
+"MUe=3600;//in cm^2/V-s\n",
+"k=1.38*10^-23;//in J/K\n",
+"De=MUe*k*T/e;//in cm^2/s\n",
+"Dh=MUh*k*T/e;//in cm^2/s\n",
+"disp(De,'Diffusion constant of electron(in cm^2/s) : ');\n",
+"disp(Dh,'Diffusion constant of hole(in cm^2/s) : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.14: Find_mobility_and_density_of_charge_carriers.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.14\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"resistivity=9*10^-3;//in ohm-m\n",
+"RH=3.6*10^-4;//in m^3-coulamb^-1\n",
+"SIGMA=1/resistivity;//in (ohm-m)^-1\n",
+"rho=1/RH;//in cooulamb/m^3\n",
+"n=rho/e;//in m^-3\n",
+"disp(n,'Density of charge carriers in m^-3 : ');\n",
+"MU=SIGMA*RH;//in m^2/V-s\n",
+"disp(MU,'Mobility in m^2/V-s : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.15: Determine_current_density.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.15\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"E=100;//in V/m\n",
+"RH=0.0145;//in m^3-coulamb^-1\n",
+"MUn=0.36;//in m^2/V-s\n",
+"J=MUn*E/RH;//in A/m^2\n",
+"disp(J,'Current density in A/m^2 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.16: Calculate_Hall_coefficients.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.16\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"n=2.05*10^22;//in m^-3\n",
+"RH=1/(n*e);//in m^3-coulamb^-1\n",
+"disp(RH,'Hall coefficient in m^3-coulamb^-1 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.17: Find_magnitude_of_hall_voltage.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.17\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"ND=10^17;//in cm^-3\n",
+"Bz=0.1;//in Wb/m^2\n",
+"w=4;//in mm\n",
+"d=4;//in mm\n",
+"Ex=5;//in V/cm\n",
+"MUe=3800;//in cm^2/V-s\n",
+"v=MUe*Ex;//in cm/s\n",
+"v=v*10^-2;//in m/s\n",
+"VH=Bz*v*d;//in mV\n",
+"disp(VH,'Magnitude of hall voltage in mV : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.18: Determine_mobility_of_holes.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.18\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"w=3;//in mm\n",
+"d=3;//in mm\n",
+"rho=200;//in Kohm-cm\n",
+"rho=rho*10^3*10^-2;//in ohm-m\n",
+"VH=50;//in mV\n",
+"VH=VH*10^-3;//in Volts\n",
+"I=10;//in uA\n",
+"I=I*10^-6;//in Ampere\n",
+"Bz=0.1;//in Wb/m^2\n",
+"RH=VH*w*10^-3/(Bz*I)\n",
+"MUh=RH/rho;//in m^2/V-s\n",
+"disp(MUh,'Mobility of holes in p-type Si bar in m^2/V-s : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.19: Determine_Hall_Voltage.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.19\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"ND=10^21;//in m^-3\n",
+"Bz=0.2;//in T\n",
+"d=4;//in mm\n",
+"d=d*10^-3;//in meter\n",
+"J=600;//in A/m^2\n",
+"n=ND;//in m^-3\n",
+"//formula : VH*w/(B*I)=1/(n*e)\n",
+"VH=Bz*J*d/(n*e);//in V\n",
+"disp(VH*10^3,'Magnitude of hall voltage in mV : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.1: Calculate_the_velocity_of_electron_at_fermi_level.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.1\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"E=2.1;//in eV\n",
+"E=E*1.602*10^-19;//in Joule\n",
+"m=9.107*10^-31;//in Kg\n",
+"//Formula : E= (m*v^2)/2\n",
+"v=sqrt(2*E/m);//in m/s\n",
+"disp(v,'Velocity of electron at fermi level in m/s : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.20: Calculate_Hall_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.20\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"e=1.6*10^-19;//in coulamb\n",
+"rho=0.00912;//in ohm-m\n",
+"B=0.48;//in Wb/m^2\n",
+"RH=3.55*10^-4;//in m^3-coulamb^-1\n",
+"SIGMA=1/rho;//in (ohm=m)^-1\n",
+"THETAh=atand(SIGMA*B*RH);//in Degree\n",
+"disp(THETAh,'Hall angle in degree : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.2: Determine_Drift_Velocity_of_Electrons.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"J=2.4;//in A/mm^2\n",
+"J=J*10^6;//in A/m^2\n",
+"n=5*10^28;//electrons/m^3\n",
+"e=1.6*10^-19;//constant\n",
+"//Formula : J=e*n*v\n",
+"v=J/(e*n);//in m/s\n",
+"disp(v*10^3,'Velocity of electron at fermi level in mm/s : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.3: Calculate_magnitude_of_currrent.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"n=10^24;//electrons/m^3\n",
+"e=1.6*10^-19;//constant\n",
+"v=1.5*10^-2;//in m/s\n",
+"A=1;//in cm^2\n",
+"A=1*10^-4;//in m^2\n",
+"I=e*n*v*A;//in Ampere\n",
+"disp(I,'Magnitude of current in Ampere : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.4: Find_electron_and_hole_densities.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ni=2.5*10^13;//in atoms/cm^3\n",
+"rho=0.039;//in ohm-cm\n",
+"SIGMAn=1/rho;//in (ohm-cm)^-1\n",
+"e=1.6*10^-19;//constant\n",
+"MUe=3600;//in cm^2/V-s\n",
+"//formula : SIGMAn=n*e*MUe=Nd*e*MUe\n",
+"Nd=SIGMAn/(e*MUe);//in atoms/cm^3\n",
+"n=Nd;//in atoms/cm^3\n",
+"p=ni^2/n;//in atoms/cm^3\n",
+"disp(n,'Electron density in atoms/cm^3 : ');\n",
+"disp(p,'Hole density in atoms/cm^3 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.5: Calculate_concentrations_in_semiconductor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"DonorImpurity=1/10^6;;//impurity per atom\n",
+"SiAtomCon=5*10^22;//in cm^-3\n",
+"ni=1.45*10^10;//in cm^-3\n",
+"MUe=1300;//in cm^2/V-s\n",
+"e=1.6*10^-19;//constant\n",
+"//part (i)\n",
+"Nd=SiAtomCon*DonorImpurity;//in cm^-3\n",
+"disp(Nd,'Donor atom concentration in cm^-3 : ');\n",
+"//part (ii)\n",
+"n=Nd;//in cm^-3\n",
+"disp(n,'Mobile electron concentration in cm^-3: ');\n",
+"//part (iii)\n",
+"p=ni^2/Nd;//in cm^-3\n",
+"disp(p,'Hole concentration in cm^-3 : ');\n",
+"//part (iv)\n",
+"SIGMA=n*e*MUe;//in (ohm-cm)^-1\n",
+"disp(SIGMA,'Conductivity of doped silicon sample in (ohm-cm)^-1 : ');\n",
+"//part (v)\n",
+"rho=1/SIGMA;//in ohm-cm\n",
+"l=0.5;//in cm\n",
+"A=(50*10^-4)^2;//in cm^2\n",
+"R=rho*l/A;//in ohm\n",
+"disp(rho,'Resistivity in ohm-cm : ');\n",
+"disp(R,'Resistance in ohm : ')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.6: Find_ratio_of_electron_to_hole_concentration.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ni=1.4*10^18;//in atoms/m^3\n",
+"Nd=1.4*10^24;//in atoms/m^3\n",
+"n=Nd;//in atoms/m^3\n",
+"p=ni^2/n;//in atoms/m^3\n",
+"ratio=n/p;//unitless\n",
+"disp(p,'Concentration of holes in per m^3 : ');\n",
+"disp(ratio,'Ratio of electron to hole concentration : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.7: Calculate_relaxation_time_resistivity_and_velocity_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.7\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Ef=5.5;//in eV\n",
+"MUe=7.04*10^-3;//in m^2/V-s\n",
+"n=5.8*10^28;//in m^-3\n",
+"e=1.6*10^-19;//constant\n",
+"m=9.1*10^-31;//in Kg\n",
+"//part (i)\n",
+"tau=MUe*m/e;//in sec\n",
+"disp(tau,'Relaxation time in sec : ');\n",
+"rho=1/(n*e*MUe);//in ohm-m\n",
+"disp(rho,'Resistivity of conductor in ohm-m : ')\n",
+"vF=sqrt(2*Ef*1.6*10^-19/m);\n",
+"disp(vF,'velocity of electron with fermi energy in m/s : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.8: Find_conductivity_and_resistivity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.8\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ni=2.5*10^13;//in cm^-3\n",
+"e=1.6*10^-19;//in coulamb\n",
+"MUh=1800;//in cm^2/V-s\n",
+"MUe=3800;//in cm^2/V-s\n",
+"SIGMAi=ni*e*(MUe+MUh);//in (ohm-cm)^-1\n",
+"RHOi=1/SIGMAi;//in ohm-cm\n",
+"disp(SIGMAi,'Intrinsic conductivity in (ohm-cm)^-1 : ');\n",
+"disp(RHOi,'Intrinsic resistivity in ohm-cm : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.9: Calculate_density_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 2.9\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"SIGMAi=2.12766;//in S/m\n",
+"RHOi=0.47;//in ohm-m\n",
+"MUh=0.19;//in m^2/V-s\n",
+"MUe=0.39;//in m^2/V-s\n",
+"e=1.6*10^-19;//in coulamb\n",
+"//Formula : SIGMAi=ni*e*(MUe+MUh)\n",
+"ni=SIGMAi/(e*(MUe+MUh));//in m^-3\n",
+"E=10^4;//in V/m\n",
+"vn=MUe*E;//in m/s\n",
+"vh=MUh*E;//in m/s\n",
+"disp(ni,'Density of electron in intrinsic material in m^-3 : ');\n",
+"disp(vn,'Drift velocity for electrons in m/s : ');\n",
+"disp(vh,'Drift velocity for holes in m/s : ');"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/3-Excess_Carriers_in_Semiconductors.ipynb b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/3-Excess_Carriers_in_Semiconductors.ipynb
new file mode 100644
index 0000000..873ac2c
--- /dev/null
+++ b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/3-Excess_Carriers_in_Semiconductors.ipynb
@@ -0,0 +1,251 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 3: Excess Carriers in Semiconductors"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.2: Find_minimum_Energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 3.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"lambda=6000;//in Angstrum\n",
+"h=6.6*10^(-34);//Planks constant\n",
+"c=3*10^8;//speed of light in m/s\n",
+"e=1.602*10^(-19);//Constant\n",
+"phi=c*h/(e*lambda*10^(-10));\n",
+"disp(phi,'Minimum required energy in eV is :');\n",
+"//Note : Ans in the book is n ot correct"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.3: Calculate_work_function.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 3.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Emax=2.5;//maximum energy of emitted electrons in eV \n",
+"lambda=2537;//in Angstrum\n",
+"EeV=12400/lambda;//in eV\n",
+"disp(EeV,'The eV equivalent of the energy of incident photon : ');\n",
+"phi=EeV-Emax;//in eV\n",
+"disp(phi,'Work function of the cathode material is ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.4: Determine_power_absorbed_and_rate_of_excess_thermal_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 3.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"t=0.46*10^-6;//in meters\n",
+"hf=2;//in ev\n",
+"Pin=10;//in mW\n",
+"alpha=50000;// in per cm\n",
+"e=1.6*10^-19;//constant\n",
+"Io=10^-2;//in mW\n",
+"It=Io*e^(-alpha*t);//in mW\n",
+"//Part (i)\n",
+"disp('Thus power absorbed = 10-1 = 9 mW or 0.009 J/s');\n",
+"disp((2-1.43)/2,'The fraction of each photon energy unit which is converted into heat');\n",
+"//Part (ii)\n",
+"disp(((2-1.43)/2)*0.009,'Energy converted into heat in J/s:');\n",
+"//Part (iii)\n",
+"disp(0.009/(e*2),'Number of photons per second given off from recombination events :');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.5: Determine_electron_transit_time_and_photoconductor_gain.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 3.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"L=100;//in uM\n",
+"A=10&-7;//in cm^2\n",
+"th=10^-6;//in sec\n",
+"V=12;//in Volts\n",
+"ue=0.13;//in m^2/V-s\n",
+"uh=0.05;//in m^2/V-s\n",
+"E=V/(L*10^-6);//in V/m\n",
+"tn=(L*10^-6)/(ue*E);\n",
+"disp(tn,'Electron transit time in sec is ');\n",
+"Gain=(1+uh/ue)*(th/tn);\n",
+"disp(Gain,'Photoconductor gain is ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.6: Determine_current_through_diode.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 3.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given datex\n",
+"Io=0.15;//in uA\n",
+"V=0.12;//in mVolt\n",
+"Vt=26;//in mVolt\n",
+"I=Io*10^-6*(exp(V/(Vt*10^-3))-1);//in A\n",
+"disp(I*10^6,'Current flowing through diode in uA is ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.7: Find_forward_voltage.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 3.7\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Io=2.5;//in uA\n",
+"I=10;//in mA\n",
+"Vt=26;//in mVolt\n",
+"n=2;//for silicon\n",
+"V=n*Vt*10^-3*log((I*10^-3)/(Io*10^-6))\n",
+"disp(V,'Forward voltage in volts is ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.8: Find_reverse_saturation_current_density.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 3.8\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ND=10^21;//in m^-3\n",
+"NA=10^22;//in m^-3\n",
+"De=3.4*10^-3;//in m^2-s^-1\n",
+"Dh=1.2*10^-3;//in m^2-s^-1\n",
+"Le=7.1*10^-4;//in meters\n",
+"Lh=3.5*10^-4;//in meters\n",
+"ni=1.6*10^16;//in m^-3\n",
+"e=1.602*10^-19;//constant\n",
+"IoA=e*ni^2*(Dh/(Lh*ND)+De/(Le*NA));\n",
+"disp(IoA*10^6,'Reverse saturation current density in uA/m2 is ')"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/4-Junction_Properties.ipynb b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/4-Junction_Properties.ipynb
new file mode 100644
index 0000000..5f242b0
--- /dev/null
+++ b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/4-Junction_Properties.ipynb
@@ -0,0 +1,660 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 4: Junction Properties"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.10: Determine_voltage_VA_in_the_circuit.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.10\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//In given circuit :\n",
+"V=15;//in volts\n",
+"Vo=0.7;//in Volts\n",
+"R=7;//in Kohm\n",
+"I=(V-2*Vo)/R\n",
+"disp('Since diode is silicon one, and the barrier potential for Si diode is 0.7 volt, Vo = 0.7 volts ');\n",
+"disp('This barrier potential acts in opposite direction to the applied voltage. The diode forward resistance is being assumed to be zero.');\n",
+"I=(V-2*Vo)/R;//in mAmpere\n",
+"disp('Barrier potential of Si diode, Vo = 0.7 Volts');\n",
+"disp('Potential VA = Voltage drop across 7 Kohm resistor');\n",
+"VA=I*R;//in Volts\n",
+"disp(VA,'Voltagee VA in volts : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.12: Determine_temperature_coefficients.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.12\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Vz=5;//in volts\n",
+"to=25;//in degree centigrade\n",
+"t=100;//in degree centigrade\n",
+"Vdrop=4.8;//in Volts\n",
+"delVz=Vdrop-Vz;//in Volts\n",
+"delt=t-to;//in degree centigrade\n",
+"TempCoeff=delVz*100/(Vz*delt);\n",
+"disp(TempCoeff,'Temperature coefficient f zener diode in %  : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.13: Find_output_voltage_and_current_through_Zener_diode.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.13\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Vz=8;//in volts\n",
+"VS=12;//in volts\n",
+"Vout=8;//in volts\n",
+"RL=10;//in Kohm\n",
+"Rs=5;//in Kohm\n",
+"//part (a)\n",
+"disp('Output voltage will be equal to Vz i.e '+string(Vz)+' Volts');\n",
+"//part (b)\n",
+"Vrs=VS-Vout;//in volts\n",
+"disp(Vrs,'Voltage across Rs in volts : ');\n",
+"IL=Vout/RL;//in mAmpere\n",
+"Is=(VS-Vout)/Rs;//in mAmpere\n",
+"Iz=Is-IL;//in mAmpere\n",
+"disp(Iz,'Current through zener diode in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.14: Find_maximum_and_minimum_values_of_zener_diode_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.14\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Vz=50;//in volts\n",
+"VSmax=120;//in volts\n",
+"VSmin=80;//in volts\n",
+"RL=10;//in Kohm\n",
+"Rs=5;//in Kohm\n",
+"Vout=Vz;//in Volts\n",
+"disp('Output voltage will be equal to Vz i.e '+string(Vz)+' Volts');\n",
+"IL=Vout/RL;//in mAmpere\n",
+"disp('The zener current will be maximum when input voltage is maximum i.e. 120V.');\n",
+"ISmax=(VSmax-Vout)/Rs;//in mAmpere\n",
+"Izmax=ISmax-IL;//in mA\n",
+"disp(Izmax,'Maximum zener diode current in mA : ');\n",
+"disp('The zener current will be minimum when input voltage is minimum i.e. 80V.');\n",
+"Ismin=(VSmin-Vout)/Rs;//in mAmpere\n",
+"Izmin=Ismin-IL;//in mA\n",
+"disp(Izmin,'Minimum zener diode current in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.15: Design_a_regulator.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.15\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Vz=15;//in volts\n",
+"Izk=6;//in mA\n",
+"Vout=15;//in Volts\n",
+"Vs=20;//in Volts\n",
+"ILmin=10;//in mA\n",
+"ILmax=20;//in mA\n",
+"disp('the zener current will be minimum i.e. Izk = 6mA when load current is maximum i.e. ILmax = 20mA');\n",
+"RS=(Vs-Vout)/(Izk+ILmax);//in ohm\n",
+"disp('when the load current will decrease and become 10 mA, the zener current will increase and become 6+10 i.e. 16 mA. Thus the current through series resistance Rs will remain unchanged at 6+20 i.e. 26 mA. Thus voltage drop in series resistance Rs will remain constant. Consequently, the output voltage will also remain constant. ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.16: Determine_VL_IZ_and_PZ.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.16\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Vs=16;//in volts\n",
+"RL=1.2;//in Kohm\n",
+"Rs=1;//in Kohm\n",
+"//If zener open circuited\n",
+"VL=Vs*RL/(Rs+RL);//in Volts\n",
+"disp(VL,'When zener open circuited Voltage across load in volts : ');\n",
+"disp('Since voltage across load VL is less than breakdown voltage of zener diode i.e. VL < Vz. The zener diode will not conduct and VL = 8.73 Volt');\n",
+"Iz=0;//in mA\n",
+"disp(Iz,'Zener current in mA : ');\n",
+"Pz=VL*Iz;//in watts\n",
+"disp(Pz,'Power in watts : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.17: Comment_on_operation_of_circuit.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.17\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Vin=20;//in volts\n",
+"Rs=220;//in Kohm\n",
+"Vz=10;//in volts\n",
+"// part (i) RL=50;//in Kohm\n",
+"disp('For RL=50ohm :');\n",
+"RL=50;//in Kohm\n",
+"VL=Vin*RL/(RL+Rs)\n",
+"disp('Since voltage across load, VL is less than breakdown voltage of zener diode. Zener will not conduct.')\n",
+"IR=Vin/(Rs+RL);//in mA\n",
+"IL=IR;//in mA\n",
+"IZ=0;//in mA\n",
+"disp(VL,'VL in volt : ');\n",
+"disp(IL*1000,'IL in mA :');\n",
+"disp(IZ,'Iz in mA: ');\n",
+"disp(IR*1000,'IR in mA :');\n",
+"\n",
+"// part (ii) RL=200;//in Kohm\n",
+"disp('For RL=200ohm : ')\n",
+"RL=200;//in Kohm\n",
+"VL=Vin*RL/(RL+Rs)\n",
+"disp('voltage across load, if zener diode is open circuited.')\n",
+"IR=Vin/(Rs+RL);//in mA\n",
+"IL=IR;//in mA\n",
+"IZ=0;//in mA\n",
+"disp(VL,'VL in volt : ');\n",
+"disp(IL*1000,'IL in mA :');\n",
+"disp(IZ,'Iz in mA: ');\n",
+"disp(IR*1000,'IR in mA :');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.18: Find_voltage_drop_across_the_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.18\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"RL=10;//in Kohm\n",
+"Rs=5;//in Kohm\n",
+"Vin=100;//in Volts\n",
+"disp('Removing the zener diode from the circuit, We have : V = Vin*RL/(RL+Rs)');\n",
+"V=Vin*RL/(RL+Rs);//in Volt\n",
+"disp(V,'Voltage V in volts = ');\n",
+"disp('V > Vz So zener diode is in ON stste.');\n",
+"VZ=50;//in Volts\n",
+"VL=VZ;//in volts\n",
+"//Apply KVL\n",
+"VR=100-50;//in Volts\n",
+"VR=50;//in Volts\n",
+"disp(VR,'Hence the voltage dropp across the 5 Kohm resistor in Volts is : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.19: Find_Ri_so_that_VL_remain_12V.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.19\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"RL=120;//in ohm\n",
+"Izmin=20;//in mA\n",
+"Izmax=200;//in mA\n",
+"VL=12;//in Volts\n",
+"VDCmin=15;//in Volts\n",
+"VDCmax=19.5;//in Volts\n",
+"Vz=12;//in Volts\n",
+"IL=VL/RL;//in Ampere\n",
+"IL=IL*1000;//in mAmpere\n",
+"//For VDCmin = 15 volts\n",
+"VSmin=VDCmin-Vz;//in Volts\n",
+"//For VDCmax = 19.5 volts\n",
+"VSmax=VDCmax-Vz;//in Volts\n",
+"ISmin=Izmin+IL;//in mA\n",
+"Ri=VSmin/ISmin;//in Kohm\n",
+"Ri=Ri*10^3;//in ohm\n",
+"disp(Ri,'The resistance Ri in ohm : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.20: Determine_range_of_RL_and_IL.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.20\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"VRL=10;//in Volts\n",
+"Vi=50;//in Volts\n",
+"R=1;//in Kohm\n",
+"Vz=10;//in Volts\n",
+"VL=Vz;//in Volts\n",
+"Izm=32;//in mA\n",
+"IR=(Vi-VL)/R;//in mA\n",
+"disp('Load current IL will be maximum when Iz = 0 ');\n",
+"Izmin=0;//in mA\n",
+"ILmax=IR-Izmin;//in mA\n",
+"disp(ILmax,'Maximum load current in mA : ');\n",
+"RLmin=VL/ILmax;//in Ohm\n",
+"disp('Load current IL will be minimum when Iz = maximum i.e. 32 mA ');\n",
+"Izmax=32;//in mA\n",
+"ILmin=IR-Izmax;//in mA\n",
+"disp(ILmin,'Minimum load current in mA : ');\n",
+"VL=Vz;//in Volts\n",
+"RLmax=VL/ILmin;//in Ohm\n",
+"disp('Hence range of RL and IL are as follows :');\n",
+"disp('Range of RL in Kohm : From '+string(RLmin)+' to '+string(RLmax));\n",
+"disp('Range of IL in mA : From '+string(ILmin)+' to '+string(ILmax));"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.2: Calculate_electron_and_hole_concentration_at_thermal_equilibrium.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"T=300;//in Kelvin\n",
+"ND=10^16;//in cm^-3\n",
+"NA=0;//in cm^-3\n",
+"ni=1.5*10^10;//in cm^-3\n",
+"no=ND/2+sqrt((ND/2)^2+ni^2);//in cm^-3\n",
+"po=ni^2/no;//in cm^-3\n",
+"disp(no,'Majority carrier electron concentration in cm^-3 : ');\n",
+"disp(po,'Minority carrier hole concentration in cm^-3 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.3: Calculate_electron_and_hole_concentration_at_thermal_equilibrium.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"T=300;//in Kelvin\n",
+"ND=3*10^15;//in cm^-3\n",
+"NA=10^16;//in cm^-3\n",
+"ni=1.6*10^10;//in cm^-3\n",
+"po=(NA-ND)/2+sqrt(((NA-ND)/2)^2+ni^2);//in cm^-3\n",
+"no=ni^2/po;//in cm^-3\n",
+"disp(po,'Majority carrier hole concentration in cm^-3 : ');\n",
+"disp(no,'Minority carrier electron concentration in cm^-3 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.4: determine_built_in_potential_barrier.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"T=300;//in Kelvin\n",
+"ND=10^15;//in cm^-3\n",
+"NA=10^18;//in cm^-3\n",
+"ni=1.5*10^10;//in cm^-3\n",
+"VT=T/11600;//in Volts\n",
+"Vbi=VT*log(NA*ND/ni^2);//in Volts\n",
+"disp(Vbi,'Built in potential barrier in volts : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.5: Obtain_value_of_contact_potential.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"T=300;//in Kelvin\n",
+"ND=10^21;//in m^-3\n",
+"NA=10^21;//in m^-3\n",
+"ni=1.5*10^16;//in m^-3\n",
+"VT=T/11600;//in Volts\n",
+"Vo=VT*log(NA*ND/ni^2);//in Volts\n",
+"disp(Vo,'Contact p;otential in volts : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.6: Determine_space_charge_width_and_electric_field.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"T=300;//in Kelvin\n",
+"ND=10^15;//in cm^-3\n",
+"NA=10^16;//in cm^-3\n",
+"ni=1.5*10^10;//in cm^-3\n",
+"VT=T/11600;//in Volts\n",
+"e=1.6*10^-19;//in Coulamb\n",
+"epsilon=11.7*8.854*10^-14;//constant\n",
+"Vbi=VT*log(NA*ND/ni^2);//in Volts\n",
+"SCW=sqrt((2*epsilon*Vbi/e)*(NA+ND)/(NA*ND));//in cm\n",
+"SCW=SCW*10^4;//in uMeter\n",
+"disp(SCW,'Space charge width in uMeters : ');\n",
+"xn=0.864;//in uM\n",
+"xp=0.086;//in uM\n",
+"Emax=-e*ND*xn/epsilon;//in V/cm\n",
+"disp(Emax,'At metallurgical junction, i.e for x=0 the electric field is peak i.e. Emax in volts : ');\n",
+"//Note : Ans in the book is wrong"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.7: Obtain_value_of_contact_potential.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.7\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"T=300;//in Kelvin\n",
+"ND=10^21;//in m^-3\n",
+"NA=10^21;//in m^-3\n",
+"ni=1.5*10^16;//in m^-3\n",
+"VT=T/11600;//in Volts\n",
+"Vo=VT*log(NA*ND/ni^2);//in Volts\n",
+"disp(Vo,'Contact potential in volts : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.8: Calculate_height_of_potential_barrier.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.8\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"T=300;//in Kelvin\n",
+"ND=8*10^14;//in cm^-3\n",
+"NA=8*10^14;//in cm^-3\n",
+"ni=2*10^13;//in cm^-3\n",
+"k=8.61*10^-5;//in eV/K\n",
+"Vo=k*T*log(NA*ND/ni^2);//in Volts\n",
+"disp(Vo,'Contact potential in volts : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.9: Find_current_in_the_circuit.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa4.9\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//In given circuit :\n",
+"V=5;//in volts\n",
+"Vo=0.7;//in Volts\n",
+"R=100;//in Kohm\n",
+"disp('Since diode is silicon one, and the barrier potential for Si diode is 0.7 volt, Vo = 0.7 volts ');\n",
+"disp('This barrier potential acts in opposite direction to the applied voltage. The diode forward resistance is being assumed to be zero.');\n",
+"I=(V-Vo)/R;//in Ampere\n",
+"disp(I*1000,'Current flowing through the circuit in Amperes :')"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/5-Junction_Properties_Continued.ipynb b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/5-Junction_Properties_Continued.ipynb
new file mode 100644
index 0000000..151d2cc
--- /dev/null
+++ b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/5-Junction_Properties_Continued.ipynb
@@ -0,0 +1,204 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 5: Junction Properties Continued"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.1: Estimate_junction_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 5.1\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ND=10^17;//in atoms/cm^3\n",
+"NA=0.5*10^16;//in atoms/cm^3\n",
+"Vo=0.7;//in Volts\n",
+"V=-10;//in Volts\n",
+"ND=ND*10^6;//in atoms/m^3\n",
+"NA=NA*10^6;//in atoms/m^3\n",
+"epsilon=8.85*10^-11;//in F/m\n",
+"e=1.6*10^-19;//coulamb\n",
+"//part (i)\n",
+"disp('When no external voltage is applied i.e. V=0');\n",
+"disp('VB = 0.7 volts');\n",
+"VB=0.7;//in Volts\n",
+"W=sqrt(2*epsilon*VB*(1/NA+1/ND)/e);//in m\n",
+"disp(W,'When no external voltage is applied, Junction width in meter : ');\n",
+"//part (ii)\n",
+"disp('When external voltage of -10 volt is applied');\n",
+"disp('VB = Vo-V volts');\n",
+"VB=Vo-V;//in Volts\n",
+"W=sqrt(2*epsilon*VB*(1/NA+1/ND)/e);//in m\n",
+"disp(W,'When external voltage of -10 Volt is applied, Junction width in meter : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.3: Find_new_position_of_fermi_level.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 5.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"Ecf=0.3;//in Volts\n",
+"T=27+273;//in Kelvin\n",
+"delT=55;//in degree centigrade\n",
+"//formula : Ecf=Ec-Ef=K*T*log(nc/ND)\n",
+"//let K*log(nc/ND)=y\n",
+"//Ecf=Ec-Ef=T*y\n",
+"y=Ecf/T;//assumed\n",
+"Tnew=273+55;//in Kelvin\n",
+"EcfNEW=y*Tnew;//in Volts\n",
+"disp(EcfNEW,'New position of fermi level is(eV) : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.4: Calculate_height_of_potential_barrier.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 5.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ND=8*10^14;//in cm^-3\n",
+"NA=8*10^14;//in cm^-3\n",
+"ni=2*10^13;//in cm^-3\n",
+"T=300;//in Kelvin\n",
+"k=8.61*10^-5;//in eV/K\n",
+"e=1.6*10^-19;//coulamb\n",
+"Vo=k*T*log(ND*NA/ni^2);//in Volts\n",
+"disp(Vo,'Potential barrier in volts : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.5: Find_electron_and_hole_concentration.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 5.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ND=2*10^16;//in cm^-3\n",
+"NA=5*10^15;//in cm^-3\n",
+"Ao=4.83*10^21;//constant\n",
+"T=300;//in Kelvin\n",
+"EG=1.1;//in eV\n",
+"kT=0.026;//in eV\n",
+"ni=Ao*T^(3/2)*exp(-EG/(2*kT));//in m^-3\n",
+"ni=ni*10^-6;//in cm^-3\n",
+"p=(ni^2)/ND;//in cm^-3\n",
+"n=(ni^2)/NA;//in cm^-3\n",
+"disp(p,'Hole concentration in cm^-3 : ');\n",
+"disp(n,'electron concentration in cm^-3 : ');\n",
+"disp('Since elctron concentration is mote than hole concentration, the given Si is of N-type.');\n",
+"//Note : Ans in the book is wrong. Mistake in value putting. "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.6: Determine_junction_capacitance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 5.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"CTzero=50;//in pF\n",
+"VR=8;//in Volt\n",
+"VK=0.7;//in Volt\n",
+"n=1/3;//for Si\n",
+"CT=CTzero/((1+VR/VK)^n);//in pF\n",
+"disp(CT,'Junction capacitance in pF : ');"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/6-Bipolar_Junction_Transistors.ipynb b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/6-Bipolar_Junction_Transistors.ipynb
new file mode 100644
index 0000000..7772c85
--- /dev/null
+++ b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/6-Bipolar_Junction_Transistors.ipynb
@@ -0,0 +1,578 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 6: Bipolar Junction Transistors"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.10: Determine_collector_emitter_voltage_and_base_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.10\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"VCC=10;//in volt\n",
+"RL=800;//in ohm\n",
+"VL=0.8;//in volt\n",
+"alfa=0.96;//unitless\n",
+"//VR=IC*RL\n",
+"VCE=VCC-VL;//in Volt\n",
+"disp(VCE,'Collector-emitter Voltage in volts : ');\n",
+"IC=VL*1000/RL;//in mA\n",
+"Beta=alfa/(1-alfa);//unitless\n",
+"IB=IC/Beta;//in mA\n",
+"disp(IB*1000,'Base current in uA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.11: Determine_collector_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.11\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"alfao=0.98;//unitless\n",
+"ICO=10;//in uA\n",
+"ICO=ICO*10^-3;//in mA\n",
+"IB=0.22;//in mA\n",
+"IC=(alfao*IB+ICO)/(1-alfao);//in mA\n",
+"disp(IC,'Collector current in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.12: Calculate_dynamic_input_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.12\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"delVEB=250;//in mVolts\n",
+"delIE=1;//in mA\n",
+"rin=delVEB/delIE;//in ohm\n",
+"disp(rin,'Dynamic input resistance in ohm : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.13: Calculate_dynamic_output_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.13\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"delVCE=10-5;//in Volts\n",
+"delIC=5.8-5;//in mA\n",
+"rin=delVCE/delIC;//in Kohm\n",
+"disp(rin,'Dynamic output resistance in Kohm : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.14: Determine_operating_point.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.14\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"VCC=10;//in volt\n",
+"RC=8;//in Kohm\n",
+"Beta=40;//unitless\n",
+"IB=15;//in uA\n",
+"IB=IB*10^-3;//in mA\n",
+"// For VCE = 0 Volts\n",
+"IC=VCC/RC;//in mA\n",
+"disp(IC,'VCE=0V and IC in mA = ');\n",
+"disp('This gives a point on loasd line.');\n",
+"//For IC=0 VCE=VCC=10V :\n",
+"disp('For IC=0, VCE=VCC=10V :')\n",
+"disp('This gives another point on load line.');\n",
+"IC=Beta*IB;//in mA\n",
+"VCE=VCC-IC*RC;//in Volts\n",
+"disp('Operating point Q is ('+string(VCE)+'V,'+string(IC)+'mA)');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.15: Find_VCE_at_cut_off_point.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.15\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"VCC=20;//in Volt\n",
+"RC=3.3*10^3;//in ohm\n",
+"disp('Applying Kirchoffs Voltage Law : ');\n",
+"disp('VCC=IC*RC+VCE');\n",
+"disp('For cut-off point, IC=0');\n",
+"disp('Therefore, VCC=VCE');\n",
+"VCE=VCC;//in volt\n",
+"disp(VCE,'VCE at cut-off point : ');\n",
+"disp('For Saturation point, VCE = 0');\n",
+"VCE=0;//in volts\n",
+"IC=VCC/RC;//in A\n",
+"disp(IC,'IC at saturation point in mA ; ');\n",
+"disp('Therefore Load line coordinates are given as : ');\n",
+"disp('('+string(20)+'V,'+string(0)+'mA)');\n",
+"disp('('+string(VCE)+'V,'+string(IC*1000)+'mA)');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.16: Determine_VC_and_VB.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.16\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"Beta=45;//Unitless\n",
+"VBE=0.7;//in Volt\n",
+"VCC=0;//in Volt\n",
+"RB=10^5;//in ohm\n",
+"RC=1.2*10^3;//in ohm\n",
+"VEE=-9;//in Volt\n",
+"disp('Applying Kirchoffs Voltage Law in input loop we have : ');\n",
+"disp('IB*RB+VBE+VEE=0');\n",
+"IB=-(VBE+VEE)/RB;//in mA\n",
+"IC=Beta*IB;//in mA\n",
+"VC=VCC-IC*RC;//in Volts\n",
+"VB=VBE+VEE;//in Volts\n",
+"disp(VC,'VC in volts : ');\n",
+"disp(VB,'VB in volts : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.17: Find_IB_and_IC.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.17\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"Beta=100;//Unitless\n",
+"hfe=Beta;//Unitless\n",
+"VBB=5;//in Volt\n",
+"VBE=0.8;//in Volt\n",
+"RB=50*10^3;//in ohm\n",
+"RE=2*10^3;//in ohm\n",
+"VCE=0.2;//in Volt\n",
+"disp('Applying Kirchoffs Voltage Law in input loop we have : ');\n",
+"disp('VBB=IB*RB+VBE+IE*RE=IB*RB+VBE+(1+Beta)*IB*RE');\n",
+"disp('IB=(VBB-VBE)/(RB+(1+Beta)*RE)');\n",
+"IB=(VBB-VBE)/(RB+(1+Beta)*RE);//in A\n",
+"disp(IB*1000,'IB in mA : ');\n",
+"disp('Applying Kirchoffs Voltage Law in output loop we have : ');\n",
+"disp('10-IC(3*10^3)-VCE-IE(2*10^3)=0');\n",
+"IC=(10-0.2)/(5*10^3);//in A\n",
+"disp(IC*1000,'IC in mA : ');\n",
+"disp(Beta*IB,'Beta*Ib in mA = ');\n",
+"disp(IC,'IC = ');\n",
+"disp('IC > Beta*IB. Hence the transistor is in saturation with the values of IB = 0.0166 mA and IC = 1.96 mA.')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.1: Determine_emitter_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.1\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"IC=20;//in mA\n",
+"Beta=50;//Unitless\n",
+"IB=IC/Beta;//in mA\n",
+"IE=IC+IB;//in mA\n",
+"disp(IE,'Emitter current in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.2: Determine_emitter_current_amplification_factor_and_gain_factor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"IC=0.98;//in mA\n",
+"IB=20;//in uA\n",
+"IB=IB*10^-3;//in mA\n",
+"//part (i)\n",
+"IE=IB+IC;//in mA\n",
+"disp(IE,'Emitter current in mA :');\n",
+"//part (ii)\n",
+"alfa=IC/IE;//unitless\n",
+"disp(alfa,'Current amplification factor : ');\n",
+"//part (iii)\n",
+"Beta=IC/IB;//unitless\n",
+"disp(Beta,'Current gain factor : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.3: Determine_emitter_current_and_collector_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"alfaDC=0.98;//unitless\n",
+"ICBO=4;//in uA\n",
+"ICBO=ICBO*10^-3;//in mA\n",
+"IB=50;//in uA\n",
+"IB=IB*10^-3;//in mA\n",
+"//Formula : IC=alfaDC*(IB+IC)+ICBO\n",
+"IC=alfaDC*IB/(1-alfaDC)+ICBO/(1-alfaDC);//in mA\n",
+"IE=IC+IB;//in mA\n",
+"disp(IE,'Emitter current in mA : ');\n",
+"disp(IC,'Collector current in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.4: Determine_collector_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"IB=10;//in uA\n",
+"IB=IB*10^-3;//in mA\n",
+"Beta=99;//Unitless\n",
+"ICO=1;//in uA\n",
+"ICO=ICO*10^-3;//in mA\n",
+"//Formula : IC=alfa*(IB+IC)+ICO\n",
+"IC=Beta*IB+(1+Beta)*ICO;//in mA\n",
+"disp(IC,'Collector current in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.5: Calculate_dynamic_input_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"delVEB=200;//in Volts\n",
+"delIE=5;//in mA\n",
+"rin=delVEB/delIE;//in ohm\n",
+"disp(rin,'Dynamic input resistance in ohm : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.6: Determine_base_and_collector_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"alfao=0.98;//unitless\n",
+"ICO=10;//in uA\n",
+"ICO=ICO*10^-3;//in mA\n",
+"IE=2;//in mA\n",
+"IC=alfao*IE+ICO;//in mA\n",
+"IB=IE-IC;//in mA\n",
+"disp(IC,'Collector current in mA : ');\n",
+"disp(IB*1000,'Base current in uA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.7: Determine_current_gain_and_base_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.7\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"ICBO=12.5;//in uA\n",
+"ICBO=ICBO*10^-3;//in mA\n",
+"IE=2;//in mA\n",
+"IC=1.97;//in mA\n",
+"alfa=(IC-ICBO)/IE;//unitless\n",
+"IB=IE-IC;//in mA\n",
+"disp(alfa,'Current gain : ');\n",
+"disp(IB,'Base current in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.8: Determine_base_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.8\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"RL=4;//in Kohm\n",
+"VL=3;//in volt\n",
+"alfa=0.96;//unitless\n",
+"IC=VL/RL;//in mA\n",
+"IE=IC/alfa;//in mA\n",
+"IB=IE-IC;//in mA\n",
+"disp(IB,'Base current in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.9: Determine_base_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 6.9\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data\n",
+"RL=1;//in Kohm\n",
+"VL=1.2;//in volt\n",
+"Beta=60;//unitless\n",
+"IC=VL/RL;//in mA\n",
+"IB=IC/Beta;//in mA\n",
+"disp(IB*1000,'Base current in uA : ');"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/7-Field_Effect_Transistors.ipynb b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/7-Field_Effect_Transistors.ipynb
new file mode 100644
index 0000000..95a55d1
--- /dev/null
+++ b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/7-Field_Effect_Transistors.ipynb
@@ -0,0 +1,335 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 7: Field Effect Transistors"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.10: Determine_Drain_current.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.10\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"ID_on=5;//in mA\n",
+"VGS=6;//in Volt\n",
+"VGS_on=8;//in Volt\n",
+"VGST=4;//in Volt\n",
+"K=ID_on/(VGS_on-VGST)^2;//in mA/V^2\n",
+"ID=K*(VGS-VGST)^2;//in mA\n",
+"disp(ID,'When VGS=6V the drain current in mA : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.1: Determine_resistance_between_gate_and_source.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.1\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"VGS=10;//in Volt\n",
+"IG=0.001;//in uA\n",
+"IG=IG*10^-6;//in A\n",
+"RGS=VGS/IG;//in ohm\n",
+"disp(RGS/10^6,'Resistance between gate and source in Mohm ; ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.2: Calculate_AC_drain_resistance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"delVDS=1.5;//in Volt\n",
+"delID=120;//in uA\n",
+"delID=120*10^-6;//in A\n",
+"rd=delVDS/delID;//in Ohm\n",
+"disp(rd*10^-3,'AC drain resistance of JFET in Kohm : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.3: Determine_Transconductance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"VP=-4.5;//in Volt\n",
+"IDSS=10;//in mA\n",
+"IDS=2.5;//in mA\n",
+"disp('From shockleys equation, drain source current, IDS=IDSS*(1-VGS/VP)^2 ');\n",
+"VGS=VP*(1-sqrt(IDS/IDSS));//in Volt\n",
+"gm=(-2*IDSS/VP)*(1-VGS/VP);//in mA/Volt\n",
+"disp(gm,'Transconductance in mA/Volt : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.4: Calculate_VGS.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"gm=10;//in mS\n",
+"IDSS=10;//in uA\n",
+"IDSS=IDSS-10^-6;//in Ampere\n",
+"disp('VGS(OFF) : VGS=VP');\n",
+"disp('gm=gmo=-2*IDSS/VP=-2*IDSS/VGS(OFF)');\n",
+"VGS_OFF=-2*IDSS/gm\n",
+"disp(round(VGS_OFF),'VGS(OFF) in mV :');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.5: Determine_minimum_value_of_VDS.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.5\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"VP=-4;//in Volt\n",
+"IDSS=10;//in mA\n",
+"IDSS=IDSS*10^-3;//in Ampere\n",
+"VGS=-2;//in Volt\n",
+"ID=IDSS*(1-VGS/VP)^2;//in mA\n",
+"disp(ID*1000,'Drain current in mA : ');\n",
+"disp('The minimum value of VDS for pinch-OFF region is equal to VP. Thus the minimum value of VDS : ');\n",
+"disp(VP,'VDS(min) in volt : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.6: Findd_values_of_ID_gmo_and_gm.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.6\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"VP=-3;//in Volt\n",
+"IDSS=8.7;//in mA\n",
+"IDSS=IDSS*10^-3;//in mA\n",
+"VGS=-1;//in Volt\n",
+"ID=IDSS*(1-VGS/VP)^2;//in Ampere\n",
+"disp(ID*1000,'ID in mA : ')\n",
+"gmo=-2*IDSS/VP;//in mS\n",
+"disp(gmo*1000,'gmo in mS : ');\n",
+"gm=gmo*(1-VGS/VP);//in mS\n",
+"disp(gm*1000,'gm in mS : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.7: Findd_values_of_ID_and_gm.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.7\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"VP=-3;//in Volt\n",
+"IDSS=8.4;//in mA\n",
+"VGS=-1.5;//in Volt\n",
+"ID=IDSS*(1-VGS/VP)^2;//in mA\n",
+"disp(ID,'Drain current in mA : ');\n",
+"gmo=-2*IDSS/VP;//in mS\n",
+"gm=gmo*(1-VGS/VP);//in mS\n",
+"disp(gm,'gm in mS : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.8: Find_value_of_VGS_and_gm.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.8\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"VP=-4.5;//in Volt\n",
+"IDSS=9;//in mA\n",
+"IDSS=IDSS*10^-3;//in Ampere\n",
+"IDS=3;//in mA\n",
+"IDS=IDS*10^-3;//in Ampere\n",
+"VGS=VP*(1-sqrt(IDS/IDSS));//in Volt\n",
+"disp(VGS,'IDS = 3 mA when VGS(in Volt) is :  ');\n",
+"gm=(-2*IDSS/VP)*(1-VGS/VP);//in mS\n",
+"disp(gm*1000,'IDS = 3 mA when gm(in mS) is :  ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.9: Sketch_the_transfer_Characteristics.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 7.9\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"VP=-4;//in Volt\n",
+"IDSS=10;//in mA\n",
+"VGS=[0 1 -1 -2 -4];\n",
+"ID=zeros(1,5);\n",
+"for i=1:5\n",
+"    ID(i)=IDSS*(1-VGS(i)/VP)^2;//in mA    \n",
+"end\n",
+"plot2d(VGS,ID);"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/8-Photonic_Devices.ipynb b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/8-Photonic_Devices.ipynb
new file mode 100644
index 0000000..592fea1
--- /dev/null
+++ b/Fundamentals_Of_Electronic_Devices_by_J_B_Gupta/8-Photonic_Devices.ipynb
@@ -0,0 +1,192 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 8: Photonic Devices"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.1: Determine_steady_state_photo_current_density.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 8.1\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"NA=10^22;//in atoms/m^3\n",
+"ND=10^22;//in atoms/m^3\n",
+"De=25*10^-4;//in m^2/s\n",
+"Dh=10^-3;//in m^2/s\n",
+"TAUeo=500;//in ns\n",
+"TAUho=100;//in ns\n",
+"ni=1.5*10^16;//in atoms/m^3\n",
+"VR=-10;//in Volt\n",
+"epsilon=11.6*8.854*10^-12;//in F/m\n",
+"e=1.6*10^-19;//in Coulamb\n",
+"VT=26;//in mV\n",
+"GL=10^27;//in m^-3 s^-1\n",
+"\n",
+"Le=sqrt(De*TAUeo*10^-9);//in um\n",
+"Le=Le*10^6;//in um\n",
+"Lh=sqrt(Dh*TAUho*10^-9);//in um\n",
+"Lh=Lh*10^6;//in um\n",
+"Vbi=VT*10^-3*log(NA*ND/ni^2);//in Volt\n",
+"Vo=Vbi;//in Volt\n",
+"VB=Vo-VR;//in Volt\n",
+"W=sqrt((2*epsilon*VB/e)*(1/NA+1/ND));//in um\n",
+"W=W*10^6;//in um\n",
+"JL=e*(W+Le+Lh)*10^-6*GL;//in A/cm^2\n",
+"disp(JL/10^4,'Steady state photocurrent density in A/cm^2 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.2: Determine_photo_current_density.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 8.2\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"W=25;//in um\n",
+"PhotonFlux=10^21;//in m^2s^-1\n",
+"alfa=10^5;//in m^-1\n",
+"e=1.6*10^-19;//in Coulambs\n",
+"GL1=alfa*PhotonFlux;//in m^-3s^-1\n",
+"GL2=alfa*PhotonFlux*exp(-alfa*W*10^-6);//in m^-3s^-1\n",
+"JL=e*PhotonFlux*(1-exp(-alfa*W*10^-6));//in mA/cm^2\n",
+"disp(JL/10,'Steady state photocurrent density in mA/cm^2 : ');"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.3: Determine_open_circuit_voltage.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 8.3\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"NA=7.5*10^24;//in atoms/m^3\n",
+"ND=1.5*10^22;//in atoms/m^3\n",
+"De=25*10^-4;//in m^2/s\n",
+"Dh=10^-3;//in m^2/s\n",
+"TAUeo=500;//in ns\n",
+"TAUho=100;//in ns\n",
+"ni=1.5*10^16;//in atoms/m^3\n",
+"VR=-10;//in Volt\n",
+"epsilon=11.6*8.854*10^-12;//in F/m\n",
+"e=1.6*10^-19;//in Coulamb\n",
+"VT=26;//in mV\n",
+"GL=10^27;//in m^-3 s^-1\n",
+"\n",
+"Le=sqrt(De*TAUeo*10^-9);//in um\n",
+"Le=Le*10^6;//in um\n",
+"Lh=sqrt(Dh*TAUho*10^-9);//in um\n",
+"Lh=Lh*10^6;//in um\n",
+"JS=e*(ni^2)*(De/(Le*10^-6*NA)+De/(Lh*10^-6*ND));//in A/cm^2\n",
+"JL=12.5;//in mA/cm^2\n",
+"VOC=VT*log(1+JL/JS);//in Volt\n",
+"disp(VOC,'Open circuit voltage in Volt : ');\n",
+"//Note : Answer in the book is wrong."
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.4: Determine_approximate_no_of_solar_cell_required.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"//Exa 8.4\n",
+"clc;\n",
+"clear;\n",
+"close;\n",
+"//given data :\n",
+"\n",
+"disp('Each cell supplies 50 mA at 0.45V. Allowing for the voltage drop across the rectifier and series resistor, a maximum output voltage of approximately 28V is required. Thus,  ');\n",
+"disp('n = Vout/Vcell');\n",
+"Vout=28;//in Volts\n",
+"Vcell=0.45;//in Volt\n",
+"n=Vout/Vcell;//Unitless\n",
+"disp(n,'No. of series connected- cells = ');\n",
+"disp('the charge taken from the batteries over a period of 24 hour is 24*0.5 =  12 Ah. thus, the charge delivered by the solar cells must be 12 ampere Hours');\n",
+"disp('Since the solar cells are illuminated only 12 hours a day, the necessary charging current from the solar cell is 12Ah/12h i.e. 1 A');\n",
+"Iout=1;//in A\n",
+"Icell=50;//in mA\n",
+"m=Iout/(Icell*10^-3);//unitless\n",
+"disp(m,'Hence total no. of group of cells in parallel, m ');\n",
+"disp(round(m*n),'The total no. of cells required : ');\n",
+"//Note : Answer in the book is wrong."
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}