The document provides an overview of solar resource evaluation methodology. It discusses the need to evaluate solar radiation for energy system studies and compares classical evaluation using measurements to evaluation from satellite images. The procedure involves determining what inputs are needed like location and technology information before choosing a methodology. Measurement-based or satellite-based approaches are outlined. Key aspects of solar radiation like daily and seasonal cycles are summarized. Methods for estimating components like beam and diffuse radiation are presented. The document also reviews instrumentation and databases for measurements.
IrSOLaV is a Spanish company that provides solar resource consulting services and data. It was spun off from CIEMAT by researchers with experience in solar energy and radiation. IrSOLaV provides time series solar radiation data from 1994-2012 for India generated from Meteosat satellites. It also provides solar resource reports, typical meteorological year data, plant performance analyses, and consulting services on measuring and analyzing solar radiation data. IrSOLaV works with several research initiatives and partners in solar energy.
This chapter discusses simple harmonic motion (SHM). SHM is defined as periodic motion where the acceleration is directly proportional to and opposite of the displacement from equilibrium. The key equations of SHM are introduced, including the displacement equation x = A sin(ωt + φ) and equations for velocity, acceleration, kinetic energy, and potential energy using angular frequency ω. Examples of SHM include a simple pendulum and spring oscillations. Exercises are provided to apply the kinematic equations of SHM.
This chapter discusses refraction of light, including:
- The index of refraction, which is the ratio of the speed of light in a vacuum to its speed in a medium.
- Snell's law, which relates the angles of incidence and refraction based on the indices of refraction of the media.
- Total internal reflection, which occurs when light travels from an optically dense medium to a less dense one at an angle greater than the critical angle.
- Wavelength changes when light moves between media due to the index of refraction.
Several example problems are worked through applying these concepts to compute angles, indices of refraction, wavelengths and speeds of light in various materials.
1) The document provides examples of physics problems involving relativity, the photoelectric effect, and waves and particles. It includes 22 sample problems with calculations related to topics such as relativistic time dilation, relativistic length contraction, photon energy, electron kinetic energy, momentum, and de Broglie wavelength.
2) Problem 38-13 calculates the work function and kinetic energy of photoelectrons emitted from a metal surface illuminated by light of a given wavelength. It finds the work function is 1.04 eV and the kinetic energy of the emitted electrons is 2.07 eV.
3) Problem 38-21 determines the de Broglie wavelength of an electron accelerated through a potential difference. It finds the electron's momentum and calculates
The 3D Smith Chart program is a new Java tool for visualizing and designing active and passive microwave circuits. It generalizes the traditional 2D Smith chart onto the surface of a sphere, addressing limitations of the 2D chart. Key features include reading measurement files, plotting reflection coefficients for complex impedances, and aiding oscillator and amplifier design by visualizing infinite mismatch and stability circles. The tool aims to provide a complete graphical solution for microwave circuit measurement and design.
This document contains 33 problems about light and illumination. It covers topics like the electromagnetic spectrum, wavelength and frequency calculations, the speed of light, light rays and shadows, illumination of surfaces, and luminous intensity. Many problems involve calculating unknown values like wavelength, frequency, time, distance, or intensity given other known values in an optics or illumination scenario.
Smith chart:A graphical representation.amitmeghanani
The document discusses the Smith chart, which is a graphical tool used to solve transmission line problems. Some key points:
- The Smith chart was developed in 1939 and allows tedious transmission line calculations to be done graphically.
- It provides a mapping between the normalized impedance plane and the reflection coefficient plane. Circles of constant resistance and reactance are plotted, along with the reflection coefficient.
- Parameters like impedance, admittance, reflection coefficient, VSWR can all be plotted and derived from locations on the chart.
- Examples are given of using the Smith chart to determine input impedance, reflection coefficient, and stub matching of transmission lines with various termination impedances.
This document provides an overview of key concepts in ray optics, including:
1. Refraction is defined as the change in direction and speed of light when passing from one medium to another. Snell's law describes the relationship between angles of incidence and refraction.
2. Total internal reflection occurs when light passes from an optically dense to a rare medium at an angle greater than the critical angle, causing the light to reflect back into the dense medium.
3. Spherical lenses can be either convex or concave. The lens maker's formula and thin lens equation describe the imaging properties and magnification of thin lenses based on the focal length and object and image distances.
IrSOLaV is a Spanish company that provides solar resource consulting services and data. It was spun off from CIEMAT by researchers with experience in solar energy and radiation. IrSOLaV provides time series solar radiation data from 1994-2012 for India generated from Meteosat satellites. It also provides solar resource reports, typical meteorological year data, plant performance analyses, and consulting services on measuring and analyzing solar radiation data. IrSOLaV works with several research initiatives and partners in solar energy.
This chapter discusses simple harmonic motion (SHM). SHM is defined as periodic motion where the acceleration is directly proportional to and opposite of the displacement from equilibrium. The key equations of SHM are introduced, including the displacement equation x = A sin(ωt + φ) and equations for velocity, acceleration, kinetic energy, and potential energy using angular frequency ω. Examples of SHM include a simple pendulum and spring oscillations. Exercises are provided to apply the kinematic equations of SHM.
This chapter discusses refraction of light, including:
- The index of refraction, which is the ratio of the speed of light in a vacuum to its speed in a medium.
- Snell's law, which relates the angles of incidence and refraction based on the indices of refraction of the media.
- Total internal reflection, which occurs when light travels from an optically dense medium to a less dense one at an angle greater than the critical angle.
- Wavelength changes when light moves between media due to the index of refraction.
Several example problems are worked through applying these concepts to compute angles, indices of refraction, wavelengths and speeds of light in various materials.
1) The document provides examples of physics problems involving relativity, the photoelectric effect, and waves and particles. It includes 22 sample problems with calculations related to topics such as relativistic time dilation, relativistic length contraction, photon energy, electron kinetic energy, momentum, and de Broglie wavelength.
2) Problem 38-13 calculates the work function and kinetic energy of photoelectrons emitted from a metal surface illuminated by light of a given wavelength. It finds the work function is 1.04 eV and the kinetic energy of the emitted electrons is 2.07 eV.
3) Problem 38-21 determines the de Broglie wavelength of an electron accelerated through a potential difference. It finds the electron's momentum and calculates
The 3D Smith Chart program is a new Java tool for visualizing and designing active and passive microwave circuits. It generalizes the traditional 2D Smith chart onto the surface of a sphere, addressing limitations of the 2D chart. Key features include reading measurement files, plotting reflection coefficients for complex impedances, and aiding oscillator and amplifier design by visualizing infinite mismatch and stability circles. The tool aims to provide a complete graphical solution for microwave circuit measurement and design.
This document contains 33 problems about light and illumination. It covers topics like the electromagnetic spectrum, wavelength and frequency calculations, the speed of light, light rays and shadows, illumination of surfaces, and luminous intensity. Many problems involve calculating unknown values like wavelength, frequency, time, distance, or intensity given other known values in an optics or illumination scenario.
Smith chart:A graphical representation.amitmeghanani
The document discusses the Smith chart, which is a graphical tool used to solve transmission line problems. Some key points:
- The Smith chart was developed in 1939 and allows tedious transmission line calculations to be done graphically.
- It provides a mapping between the normalized impedance plane and the reflection coefficient plane. Circles of constant resistance and reactance are plotted, along with the reflection coefficient.
- Parameters like impedance, admittance, reflection coefficient, VSWR can all be plotted and derived from locations on the chart.
- Examples are given of using the Smith chart to determine input impedance, reflection coefficient, and stub matching of transmission lines with various termination impedances.
This document provides an overview of key concepts in ray optics, including:
1. Refraction is defined as the change in direction and speed of light when passing from one medium to another. Snell's law describes the relationship between angles of incidence and refraction.
2. Total internal reflection occurs when light passes from an optically dense to a rare medium at an angle greater than the critical angle, causing the light to reflect back into the dense medium.
3. Spherical lenses can be either convex or concave. The lens maker's formula and thin lens equation describe the imaging properties and magnification of thin lenses based on the focal length and object and image distances.
ray optics class 12 ppt part 2 slideshareArpit Meena
1. This document summarizes key concepts in ray optics, including refraction through a prism, dispersion, angular dispersion, refractive index, compound microscopes, astronomical telescopes, and resolving power.
2. Refraction through a prism is described using angles of incidence, emergence, deviation and minimum deviation. Dispersion is explained as different colors refracting at different angles due to their different wavelengths.
3. Compound microscopes use an objective and eyepiece lens to magnify images. Astronomical telescopes form real images at focus or virtual images at infinity, with magnification determined by focal lengths.
This document provides 30 problems related to calculating forces and torques in magnetic fields. It covers topics like calculating torque on loops and coils using the torque formula, determining required currents and magnetic field strengths, and converting galvanometers into voltmeters and ammeters by adding resistances. The problems involve setting up and solving equations for torque, current, resistance, and magnetic field based on given parameters like loop/coil area, number of turns, angle with the magnetic field, and desired deflection or measurement values.
This document describes characteristics of electromagnetic waves and their behavior. It discusses how oscillating charges can generate electromagnetic waves, and how these waves consist of oscillating electric and magnetic fields that propagate perpendicularly. It also covers how electromagnetic waves transfer energy between electric and magnetic fields as they travel at the speed of light.
The document discusses key topics in microwave engineering including:
1. Maxwell's equations which describe the fundamentals of electromagnetics.
2. Explanations of important concepts like electric and magnetic fields, vectors, divergence, curl and boundary conditions.
3. An overview of industries utilizing RF components and analysis of the RF components market including development trends, major companies and factors changing the industry.
The Smith chart is a graphical tool used to analyze high frequency circuits. It represents all possible complex impedances in terms of the reflection coefficient. Circles of constant resistance and arcs of constant reactance intersect on the chart to indicate impedance values. The chart allows users to determine impedances, reflection coefficients, voltage standing wave ratios and other transmission line parameters through graphical techniques. It remains a popular tool decades after its original conception due to providing a clever way to visualize complex impedance functions.
1) A spacecraft measures the redshift of photons emitted from the surface of a star to determine the star's mass M and radius R. As it approaches the star, it measures the velocity needed for resonant absorption of photons by He+ ions.
2) The experimental data gives the velocity needed for resonance at different distances from the star. This data is plotted to determine M and R graphically.
3) In addition to gravitational redshift, the emitted photons will experience a small relativistic frequency shift due to the recoil of the emitting atom. This effect is much smaller than the gravitational redshift.
Plane waves have parallel planar wavefronts that propagate indefinitely, while a laser beam has wavefronts that diverge from an initial waist, transitioning from planar to spherical. A laser produces a coherent, monochromatic beam through stimulated emission within an optical cavity. The Gaussian beam equation describes the amplitude, phase, and beam width of a laser beam as it propagates, accounting for its localized amplitude profile and changing wavefront curvature compared to plane waves.
This document summarizes key concepts from Chapter 24 of a physics textbook on electric fields.
1) It provides examples of calculating electric field intensity (E) given force (F) on a charge (q) or vice versa.
2) It explains how to find the resultant electric field (ER) between two or more charges using vector addition.
3) It introduces Gauss's law and shows how it can be used to calculate E outside a charged sphere or hollow sphere.
Normal Modes Analysis can be used to estimate full 2D velocity vectors from radial CODAR measurements in tidal channels. It models flow as a series of eigenfunctions satisfying the boundary conditions. By fitting the radial radar data to the Normal Modes solutions, coefficients for each mode can be determined via least squares. This allows reconstruction of the full velocity field and visualization of particle trajectories over time, providing insight into tidal flow dynamics. Future work aims to validate the method against direct measurements during flow reversals and determine the optimal number of modes.
This document discusses the principles and types of diffraction, including Fraunhofer and Fresnel diffraction. It explains diffraction at a single slit and double slit, describing how the diffraction patterns are formed and the conditions for maxima and minima. It also discusses the differences between interference and diffraction. Finally, it discusses diffraction gratings and their uses in spectroscopy.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
OMAE2009-79380: Mitigation of Vortex-Induced Motions of a Monocolumn PlatformRodolfo Gonçalves
A great deal of works has been developed on the Spar VIM issue. There are, however, very few published works concerning VIM of monocolumn platforms, partly due to the fact that the concept is fairly recent and the first unit was only installed last year. In this context, the present paper presents a meticulous study on VIM for this type of platform concept. Model test experiments were performed to check the influence of many factors on VIM, such as different headings, wave/current coexistence, different drafts, suppression elements, and the presence of risers. The results of the experiments presented here are inline and cross-flow motion amplitudes, ratios of actual oscillation and natural periods, and motions in the XY plane. This is, therefore, a very extensive and important data set for comparisons and validations of theoretical and numerical models for VIM prediction.
Metallic rectangular-grooves based 2D reflectarray antenna excited by an open...Yong Heui Cho
This document describes a 2D reflectarray antenna composed of multiple metallic rectangular grooves excited by an open-ended parallel-plate waveguide. The scattering solutions for the antenna are obtained using an overlapping T-block method and Stratton-Chu formula. Design formulas for phase matching are proposed to achieve high directivity and beam tilting. Numerical computations of scattering characteristics like gain and focus offset are performed. A prototype antenna was fabricated for testing and measurement.
This document discusses the technique of gravitational microlensing to discover extrasolar planets. Gravitational microlensing occurs when a star or planet bends the light of a more distant star, causing its brightness to appear magnified. For single lenses, the lens equation can describe the system. For multiple lenses like a star-planet system, the lens equation must be solved numerically. Microlensing events are detected by measuring the light curve of a lensed star over time. Parameters like mass ratios and Einstein crossing times can then be estimated by fitting theoretical light curves to the data. While individual lens masses cannot be directly measured, microlensing provides a method to detect planets that is not dependent on the host star's light.
Why are stochastic networks so hard to simulate?Sean Meyn
http://arxiv.org/abs/0906.4514
Strange behavior of simulation of queues and other "skip free" stochastic models, including the R-W Hastings Metropolis algorithm.
Presented at the Workshop on Markov chains and MCMC, in honor of Persi Diaconis
http://http//pages.cs.aueb.gr/users/yiannisk/AWMCMC.html
This document discusses key concepts related to solar radiation geometry. It begins by providing background on the sun and how it generates enormous amounts of energy. It then discusses how solar radiation reaches the Earth's atmosphere and surface. Key angles used in solar radiation analysis are defined, including latitude, declination, hour angle, and others. The timing of solstices and equinoxes is explained by the changing declination angle throughout the year. Factors like direct and diffuse radiation, spectral distribution, and how solar radiation is attenuated in the atmosphere are also summarized.
A presentation by the German Aerospace Center DLR at the IRENA GCC workshop. The workshop took place in June, 2013 and was hosted by the Kuwait Institute for Scientific Research (KISR).
Solar Resource Assessment: Why it MattersAWS Truepower
Characterizing solar resources and local meteorological attributes is an important first-step in the review of any solar energy project. While residential and light commercial projects may require only a cursory assessment, larger distributed generation and utility-scale projects necessitate a more rigorous evaluation.
AWS Truepower’s President and CEO, Bruce Bailey and Director of Solar Services, Marie Schnitzer will cover the importance of using established resource assessment methods to lower project risk and improve project and site characterization. During the webinar they will share lessons-learned from the wind industry and provide insight on best practices in desktop studies, on-site monitoring programs, and field activities.
Este informe técnico analiza los datos de radiación solar medidos en la estación de STATION entre diciembre de 2005 y julio de 2009. Se realiza un análisis de calidad de los datos mediante filtros físicos y comparaciones entre las componentes medidas para verificar su precisión. También se comparan los datos con los de otras 5 estaciones cercanas y con un modelo de cielo despejado para validar la calidad de las mediciones a lo largo de los años.
This document defines various angles used to describe the position of the sun relative to Earth and vertical surfaces. It outlines three angles that describe the Earth's position: latitude, declination, and hour angle. It then defines three sun angles: inclination angle, zenith angle, and solar azimuth angle. Finally, it lists three surface angles: surface azimuth angle, tilt angle or slope, and angle of incidence.
ray optics class 12 ppt part 2 slideshareArpit Meena
1. This document summarizes key concepts in ray optics, including refraction through a prism, dispersion, angular dispersion, refractive index, compound microscopes, astronomical telescopes, and resolving power.
2. Refraction through a prism is described using angles of incidence, emergence, deviation and minimum deviation. Dispersion is explained as different colors refracting at different angles due to their different wavelengths.
3. Compound microscopes use an objective and eyepiece lens to magnify images. Astronomical telescopes form real images at focus or virtual images at infinity, with magnification determined by focal lengths.
This document provides 30 problems related to calculating forces and torques in magnetic fields. It covers topics like calculating torque on loops and coils using the torque formula, determining required currents and magnetic field strengths, and converting galvanometers into voltmeters and ammeters by adding resistances. The problems involve setting up and solving equations for torque, current, resistance, and magnetic field based on given parameters like loop/coil area, number of turns, angle with the magnetic field, and desired deflection or measurement values.
This document describes characteristics of electromagnetic waves and their behavior. It discusses how oscillating charges can generate electromagnetic waves, and how these waves consist of oscillating electric and magnetic fields that propagate perpendicularly. It also covers how electromagnetic waves transfer energy between electric and magnetic fields as they travel at the speed of light.
The document discusses key topics in microwave engineering including:
1. Maxwell's equations which describe the fundamentals of electromagnetics.
2. Explanations of important concepts like electric and magnetic fields, vectors, divergence, curl and boundary conditions.
3. An overview of industries utilizing RF components and analysis of the RF components market including development trends, major companies and factors changing the industry.
The Smith chart is a graphical tool used to analyze high frequency circuits. It represents all possible complex impedances in terms of the reflection coefficient. Circles of constant resistance and arcs of constant reactance intersect on the chart to indicate impedance values. The chart allows users to determine impedances, reflection coefficients, voltage standing wave ratios and other transmission line parameters through graphical techniques. It remains a popular tool decades after its original conception due to providing a clever way to visualize complex impedance functions.
1) A spacecraft measures the redshift of photons emitted from the surface of a star to determine the star's mass M and radius R. As it approaches the star, it measures the velocity needed for resonant absorption of photons by He+ ions.
2) The experimental data gives the velocity needed for resonance at different distances from the star. This data is plotted to determine M and R graphically.
3) In addition to gravitational redshift, the emitted photons will experience a small relativistic frequency shift due to the recoil of the emitting atom. This effect is much smaller than the gravitational redshift.
Plane waves have parallel planar wavefronts that propagate indefinitely, while a laser beam has wavefronts that diverge from an initial waist, transitioning from planar to spherical. A laser produces a coherent, monochromatic beam through stimulated emission within an optical cavity. The Gaussian beam equation describes the amplitude, phase, and beam width of a laser beam as it propagates, accounting for its localized amplitude profile and changing wavefront curvature compared to plane waves.
This document summarizes key concepts from Chapter 24 of a physics textbook on electric fields.
1) It provides examples of calculating electric field intensity (E) given force (F) on a charge (q) or vice versa.
2) It explains how to find the resultant electric field (ER) between two or more charges using vector addition.
3) It introduces Gauss's law and shows how it can be used to calculate E outside a charged sphere or hollow sphere.
Normal Modes Analysis can be used to estimate full 2D velocity vectors from radial CODAR measurements in tidal channels. It models flow as a series of eigenfunctions satisfying the boundary conditions. By fitting the radial radar data to the Normal Modes solutions, coefficients for each mode can be determined via least squares. This allows reconstruction of the full velocity field and visualization of particle trajectories over time, providing insight into tidal flow dynamics. Future work aims to validate the method against direct measurements during flow reversals and determine the optimal number of modes.
This document discusses the principles and types of diffraction, including Fraunhofer and Fresnel diffraction. It explains diffraction at a single slit and double slit, describing how the diffraction patterns are formed and the conditions for maxima and minima. It also discusses the differences between interference and diffraction. Finally, it discusses diffraction gratings and their uses in spectroscopy.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
OMAE2009-79380: Mitigation of Vortex-Induced Motions of a Monocolumn PlatformRodolfo Gonçalves
A great deal of works has been developed on the Spar VIM issue. There are, however, very few published works concerning VIM of monocolumn platforms, partly due to the fact that the concept is fairly recent and the first unit was only installed last year. In this context, the present paper presents a meticulous study on VIM for this type of platform concept. Model test experiments were performed to check the influence of many factors on VIM, such as different headings, wave/current coexistence, different drafts, suppression elements, and the presence of risers. The results of the experiments presented here are inline and cross-flow motion amplitudes, ratios of actual oscillation and natural periods, and motions in the XY plane. This is, therefore, a very extensive and important data set for comparisons and validations of theoretical and numerical models for VIM prediction.
Metallic rectangular-grooves based 2D reflectarray antenna excited by an open...Yong Heui Cho
This document describes a 2D reflectarray antenna composed of multiple metallic rectangular grooves excited by an open-ended parallel-plate waveguide. The scattering solutions for the antenna are obtained using an overlapping T-block method and Stratton-Chu formula. Design formulas for phase matching are proposed to achieve high directivity and beam tilting. Numerical computations of scattering characteristics like gain and focus offset are performed. A prototype antenna was fabricated for testing and measurement.
This document discusses the technique of gravitational microlensing to discover extrasolar planets. Gravitational microlensing occurs when a star or planet bends the light of a more distant star, causing its brightness to appear magnified. For single lenses, the lens equation can describe the system. For multiple lenses like a star-planet system, the lens equation must be solved numerically. Microlensing events are detected by measuring the light curve of a lensed star over time. Parameters like mass ratios and Einstein crossing times can then be estimated by fitting theoretical light curves to the data. While individual lens masses cannot be directly measured, microlensing provides a method to detect planets that is not dependent on the host star's light.
Why are stochastic networks so hard to simulate?Sean Meyn
http://arxiv.org/abs/0906.4514
Strange behavior of simulation of queues and other "skip free" stochastic models, including the R-W Hastings Metropolis algorithm.
Presented at the Workshop on Markov chains and MCMC, in honor of Persi Diaconis
http://http//pages.cs.aueb.gr/users/yiannisk/AWMCMC.html
This document discusses key concepts related to solar radiation geometry. It begins by providing background on the sun and how it generates enormous amounts of energy. It then discusses how solar radiation reaches the Earth's atmosphere and surface. Key angles used in solar radiation analysis are defined, including latitude, declination, hour angle, and others. The timing of solstices and equinoxes is explained by the changing declination angle throughout the year. Factors like direct and diffuse radiation, spectral distribution, and how solar radiation is attenuated in the atmosphere are also summarized.
A presentation by the German Aerospace Center DLR at the IRENA GCC workshop. The workshop took place in June, 2013 and was hosted by the Kuwait Institute for Scientific Research (KISR).
Solar Resource Assessment: Why it MattersAWS Truepower
Characterizing solar resources and local meteorological attributes is an important first-step in the review of any solar energy project. While residential and light commercial projects may require only a cursory assessment, larger distributed generation and utility-scale projects necessitate a more rigorous evaluation.
AWS Truepower’s President and CEO, Bruce Bailey and Director of Solar Services, Marie Schnitzer will cover the importance of using established resource assessment methods to lower project risk and improve project and site characterization. During the webinar they will share lessons-learned from the wind industry and provide insight on best practices in desktop studies, on-site monitoring programs, and field activities.
Este informe técnico analiza los datos de radiación solar medidos en la estación de STATION entre diciembre de 2005 y julio de 2009. Se realiza un análisis de calidad de los datos mediante filtros físicos y comparaciones entre las componentes medidas para verificar su precisión. También se comparan los datos con los de otras 5 estaciones cercanas y con un modelo de cielo despejado para validar la calidad de las mediciones a lo largo de los años.
This document defines various angles used to describe the position of the sun relative to Earth and vertical surfaces. It outlines three angles that describe the Earth's position: latitude, declination, and hour angle. It then defines three sun angles: inclination angle, zenith angle, and solar azimuth angle. Finally, it lists three surface angles: surface azimuth angle, tilt angle or slope, and angle of incidence.
The document defines sunshine as direct sunlight of at least 120 w/m2 measured on the ground. It provides details on the sun's composition and radiation, including that 53.12% of its energy is in the infrared region. It also discusses how the Earth reflects 1/3 of sunlight and is inclined at 23.5 degrees on its axis. Finally, it describes various instruments used to measure solar radiation, including pyranometers and pyrheliometers, and concepts like beam radiation, diffuse radiation, and solar declination.
This document discusses different instruments used to measure solar radiation. It describes a pyranometer, which measures broadband solar irradiance on a planar surface using a thermopile sensor and glass dome. A pyrheliometer specifically measures direct solar irradiance and requires solar tracking to keep it aimed at the sun. Both instruments adhere to ISO and WMO standards and are used in meteorology, climatology and solar energy studies. A sunshine recorder measures the amount of sunshine at a location using either the sun or a clock as a timescale.
- Solar power involves converting sunlight into electricity through photovoltaic cells or concentrated solar power.
- Pakistan receives high solar radiation throughout the year, especially in remote areas not connected to the national power grid, making solar power feasible.
- Advantages of solar power in Pakistan include a free power source, no pollution, and suitability for remote areas, while disadvantages are high initial costs and reliance on sunlight.
- Several solar power plants currently operate in Pakistan and the government is promoting expansion through land allocation projects.
Solar energy is energy from the sun that can be converted into thermal or electric energy. Thermal energy from the sun is used for heating while electric energy uses photovoltaic cells to produce electricity. The document discusses the history of solar energy development and provides examples of practical solar energy applications today such as solar panels, vehicles, street lights, and water pumps. It also outlines the advantages of solar energy being renewable, sustainable, and reducing environmental impacts compared to fossil fuels. The high upfront costs of solar energy systems and dependence on sunlight availability are mentioned as disadvantages.
The document discusses moments (torques) of forces, moments of couples, and equivalent force-couple systems. It provides:
1) Definitions of the moment of a force as the tendency for rotation about a point, and the moment of a couple as two parallel forces with equal magnitude acting in opposite directions separated by a perpendicular distance.
2) Examples calculating moments of forces about a point using scalar analysis and resolving forces into components.
3) Discussion of replacing multiple forces and couples with an equivalent single force and couple moment at a point, in order to more easily understand their overall effect.
This document provides an overview of key concepts in wave optics, including:
- Electromagnetic waves and their properties like wavelength and frequency
- Wavefronts and how they are used to describe light propagation
- Huygens' principle which describes how each point on a wavefront acts as a secondary light source
- The laws of reflection and refraction based on Huygens' principle
- How wavefronts behave when interacting with mirrors, lenses, and prisms
- Conditions for coherent and interfering waves
- Young's double slit experiment and the patterns of light and dark fringes it produces
- How thin film interference can produce the colors seen in phenomena like rainbows
This document discusses various topics related to antenna fundamentals including:
1. It defines key antenna terminology such as radiation patterns, beamwidth, directivity, gain, polarization, and more.
2. It describes different categories of antenna types including loops, dipoles, slots, reflectors, patches, and more.
3. It covers antenna parameters and concepts such as radiation patterns, beam efficiency, radiation intensity, effective aperture, polarization, near and far field zones, and more.
Quantum Nanomagnetism and related phenomena
Professor Javier Tejada presented on topics related to quantum nanomagnetism including: (1) exchange and anisotropy energies that determine magnetic behavior on small scales; (2) single domain particles whose magnetic moments behave collectively; (3) molecular magnets that exhibit quantum tunneling of magnetization and resonant spin tunneling; and (4) phenomena such as quantum magnetic deflagration and potential evidence of superradiance observed in molecular magnet experiments using pulsed magnetic fields. Future directions may explore stabilizing molecular magnets above liquid nitrogen temperatures and their potential applications in memory and quantum computing.
Dynamics of Machines - Forced Vibration - Problems.pdfgowthamdeva9598
1. Vibrations from rotating or reciprocating parts in machines need to be isolated to prevent transmission to other structures. Various materials like rubber, felt, cork, and springs can provide isolation.
2. Force and motion transmissibility measure the effectiveness of isolation. Force transmissibility is the ratio of transmitted to applied force. It depends on damping ratio and frequency ratio.
3. With increased damping or decreased natural frequency, isolation is more effective as transmissibility is lower. Proper selection of isolating material stiffness and damping can optimize vibration isolation.
Physics Marking scheme| Class 12 session 2023-2024korish949
This document provides the marking scheme for CBSE Sample Question Paper for Class XII Physics session 2022-2023. It lists the questions from sections A, B, C and D along with the marks allocated to each question. Section A contains multiple choice questions with one mark each. Section B contains short answer type questions with half mark each. Section C contains questions based on derivations and explanations with varying marks. Section D contains numerical type questions with full or half marks. The document provides the answers or solutions expected for each question.
This document analyzes a circular cylindrical dipole antenna using Fourier transforms and mode matching. It presents:
1) A rigorous solution for the input impedance and current distribution of a finite circular cylindrical dipole antenna in rapidly convergent series.
2) Numerical results showing good agreement between the presented solution and experimental data for input admittance and current distribution.
3) Analysis of the effect of cylinder radius on the angular radiation pattern, which varies less than 1dB for most angles as radius increases.
A parallel-polarized uniform plane wave is incident obliquely on a lo.pdfaroraenterprisesmbd
A parallel-polarized uniform plane wave is incident obliquely on a lossless dielectric slab that is
embedded in a free-space medium, as shown in Figure P5-17. Derive expressions for the total
reflection and transmission coefficients in terms of the electrical constitutive parameters,
thickness of the slab, and angle of incidence.
Solution
In this section we look at the power or energy transmitted and reflected at an interface between
two insulators. To do so, we must evaluate the time-averaged power in the incident, reflected,
and transmitted waves which is done by calculating the Poynting vector. The energy current
density toward or away from the interface is then given by the component of the Poynting vector
in the direction normal to the interface. In the second medium, where there is just a single
(refracted) wave, the normal component of S is unambiguously the transmitted power per unit
area. But in the first medium, the total electromagnetic field is the sum of the fields of the
incident and reflected waves. In evaluating E × H, one finds three kinds of terms. There is one
which is the cross-product of the fields in the incident wave, and its normal component gives the
incident power per unit area. A second is the cross-product of the fields in the reflected wave,
giving the reflected power. But there are also two cross-terms involving the electric field of one
of the plane waves and the magnetic field of the other one. It turns out that the time-average of
the normal component of these terms is zero, so that they may be ignored in the present context.
Bearing this in mind, we have the following quantities of interest: The time-averaged incident
power per unit area:
P =< S > ·n = c 8 s ² µ |E0| 2 k · n k
The time-averaged transmitted power per unit area:
P 0 =< S 0 > ·n = c 8 s ² 0 µ0 |E 0 0 | 2k 0 · n k 0 d
The reflection coefficient R and the transmission coefficient T are defined as the ratios of the
reflected and transmitted power to the incident power. We may calculate the reflection and
transmission coefficients for the cases of polarization perpendicular and parallel to the plane of
incidence by using the Fresnel equations. If an incident wave has general polarization so that its
fields are linear combinations of these two special cases, then there is once again the possibility
of cross terms in the power involving an electric field with one type of polarization and a
magnetic field with the other type. Fortunately, these turn out to vanish, so that one may treat the
two polarizations individually. For the case of polarization perpendicular to the plane of
incidence, we use the Fresnel equations (52) and (54) for the reflected and transmitted
amplitudes and have
T = q ² 0 µ0 4n 2 cos2 i cos r (n cos i+(µ/µ0) n02n2 sin2 i) 2 q ² µ cosi
Making use of the relations n = ²µ, n 0 = ² 0µ0 , sin r = (n/n0 )sin i, and cosi = 1 sin2 i,
T = 4n(µ/µ0 ) cosi n02 n2 sin2 i [n cosi + (µ/µ0 ) n02 n2 sin2 i] 2 .
By similar means one can write the .
The document discusses electromagnetic waves, including their propagation, energy, intensity, and polarization. It defines that electromagnetic waves have oscillating electric and magnetic fields that change in sync as the waves propagate. The energy of electromagnetic waves comes equally from the electric and magnetic fields. Intensity is defined as power per unit area. Polarization is the direction of oscillation of the electric field and can be linear, circular, or unpolarized. Linear polarizers only transmit electric field components parallel to the transmission axis.
1. Light behaves as a wave and can interfere with itself when it takes multiple paths. Huygens' principle states that each point on a wavefront is a source of secondary wavelets which combine to form the new wavefront.
2. Interference occurs when two waves superimpose, with constructive and destructive interference occurring depending on the path difference between the waves. Young's double slit experiment demonstrated interference and bright and dark fringes formed on the screen.
3. Thin films can produce interference and appear colored due to the path differences between light rays reflecting and refracting within the film, with different colors seen for different path differences satisfying the interference conditions.
1) The document discusses the propagation of waves, including plane waves, cylindrical waves, and spherical waves. It describes how the amplitude of each type of wave decreases with distance from the source.
2) Huygens' principle is introduced, which models light propagation as secondary spherical wavelets emerging from each point on a propagating wavefront.
3) When light travels from one medium to another, it results in reflected and refracted waves at the interface between the media. Snell's law relates the angles of incidence and refraction.
1) Circular dichroism arises from the differential absorption of left and right circularly polarized light by chiral molecules.
2) CD spectra are more sensitive to conformational changes in proteins and nucleic acids than absorption spectra.
3) CD spectra can provide information about secondary structure in proteins.
This document discusses solar thermal power and provides an overview of solar radiation topics including:
1. The sun is an abundant source of energy that can be harnessed using solar thermal technologies.
2. It describes the solar resource and measurements of solar radiation, including quality control of data and methods to estimate radiation values.
3. It lists typical contents like the solar spectrum, relationships between the sun and earth, and databases/tools for working with solar radiation data.
This document discusses armature reaction in electrical machines. It begins by defining armature reaction as the effect of armature flux on the main field flux produced by the DC field excitation. It then analyzes armature reaction for different load types:
- With a pure resistive load, the armature flux leads the main flux by 90 degrees, causing a cross-magnetizing or distorting effect.
- With a pure inductive load, the armature flux opposes the main flux, resulting in a demagnetizing effect that reduces the air gap flux and terminal voltage.
- With a pure capacitive load, the armature flux augments the main flux, causing a magnetizing effect that increases the air
RADAR - RAdio Detection And Ranging
This is the Part 1 of 2 of RADAR Introduction.
For comments please contact me at solo.hermelin@gmail.com.
For more presentation on different subjects visit my website at http://www.solohermelin.com.
Part of the Figures were not properly downloaded. I recommend viewing the presentation on my website under RADAR Folder.
4 radio wave propagation over the earthSolo Hermelin
Describes the Electromagnetic Wave Propagation over the Earth Surface. Please send comments to solo.hermelin@gmail.com.
For more presentations on different subjects pleade visit my website at http://www,solohermelin.com.
This presentation is in the Radar folder.
1) Magnets have north and south poles that attract or repel each other depending on their orientation, similar to electric charges. The magnetic force follows a law analogous to Newton's law of gravity and Coulomb's law for electricity.
2) If a magnet is broken in half, each new piece becomes a smaller magnet with its own north and south poles, rather than separating the original poles.
3) Passing an electric current through a coil of wire or loop creates a magnetic field. The direction and strength of the magnetic field can be determined using the right hand rule.
This document discusses Maxwell's equations and electromagnetic waves through conceptual problems and examples.
Some key points:
1) Maxwell's equations apply to both time-independent and time-dependent electric and magnetic fields. The electromagnetic wave equation can be derived from Maxwell's equations.
2) Electromagnetic waves are transverse waves where the electric and magnetic fields oscillate perpendicular to the direction of propagation.
3) The momentum of an electromagnetic wave depends on its intensity, so waves of equal intensity have equal momentum regardless of frequency.
4) Radiation pressure from sunlight was determined to be causing changes to the orbit of one of the first U.S. satellites, something not accounted for in its design. Estimates
This document provides information about AC waveforms including:
- Formulas for instantaneous voltage of a sine wave in terms of peak voltage and angle.
- Conversions between peak, RMS, and average voltages.
- Relationships between frequency and period.
- Calculations of power in resistive AC circuits using RMS voltages and currents.
- Examples of calculations including instantaneous voltage, peak voltage, frequency, and power dissipation.
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Solar resource assessment luis martin
1. Luis Martín Pomares
IrSOLaV
Calle Santiago Grisolia nº2, 28760 Tres Cantos (Madrid)
luis.martin@irsolav.com
www.irsolav.com / www.solarexplorer.info
2. Introduction
Solar resources evaluation is a necessary first step for the
study of any energy system.
The objective is the determination of the solar radiation
collected in a specific site, for its use in a specific solar
technology.
As inputs, it is necessary to have information related to the
source and to the technology.
The methodologies can be classified as: classical evaluation
(from measurements), and evaluation from satellite images.
3. Procedure proposed
Time series
Hourly, monthly
What do I need? Global, DNI
Maps
For what: Report, modeling
No
Satellite information Measurements?
Any other approach
Yes
Ok?
Solar resource knowledge
4. Solar radiation characteristics
Solar energy reaches the earth in
a discontinuous form, showing
cycles or periods:
Daily cycle: accounts for 50% of
the total availability of daily hours.
Another effect of the daily cycle is
the modulation of the received
energy throughout the day.
Seasonal cycle: modulation of the
received energy throughout the
year.
5. Solar constant and solar geometry
Is the amount of solar energy
incident in 1 m2 of surface
perpendicularly exposed to
the solar rays and placed at 1
AU of distance.
Changes slightly with time, but
can be considered as constant
Ion = 1367 W/m2.(WRC).
Solar geometry is well known
We can estimate with high accuracy the solar irradiation at the top
of the atmosphere at every moment and every place
6. Interaction of solar radiation with
the atmosphere
Radiation at the top of atmosphere
Absorption (ca. 1%)
Ozone.……….…....
Rayleigh scattering and absorption (ca. 15%)
Air molecules..……
Scatter and Absorption (ca. 15%, max. 100%)
Aerosol…….………..…...……
Clouds………….……….. Reflection, Scatter, Absorption (max. 100%)
Water Vapor…….……...……… Absorption (ca. 15%)
Direct normal irradiance at ground
7. Solar Geometry
The position of the Sun can be calculated suing
the following trigonometric equations:
ZENITH
Cenital angle (θz) or its
SOL
TRAYECTORIA SOLAR
complementary solar angle (α)
(+) MAÑANA W 1
(-) ESTE
θz z z cos sin sin cos cos cos
-ψ α
ψ
S N
0
+ψ
Azimutal angle (ψ):
PROYECCION DE LA
1
TRAYECTORIA SOLAR sin cos sin / sin z
E
8. Solar radiation components
RADIATION REFLECTED BY CLOUDS
GROUND ALBEDO
ABSORPTION
SCATTERING
DIRECT NORMAL RADIATION
DIFUSE RADIATION
9. Ley of Beer
In I 0 e( k L)
I 0 e( m)
I0 T
In In d I 0 e( k L)
d ISC e m
Clear sky models or transmitance models
Bn I CS (TRToTgTwTa 0.013) Yang
C
Bn ICS exp[ 0.8662 TLAM 2 mp R ] ESRA
10. The concept of optical mass
Aproximation to plane-
parallel
1
m
cos
Karsten equation
1.253 1
m (sin 0.15( 3.885) )
11. Air mass: variability
35
30
25
Masa relativa de aire
20
15
10
5
0
4 6 8 10 12 14 16 18 20
12. Sensibility of ESRA model to TL
Influence of TLINKE and altitude above sea level on DNI for clear sky
Dia juliano=200, z=500, Lat=37º N Long=-2º E TL=4, dia juliano=200, Lat=37º N Long=-2º E
1200 1000
TL=2 z=0 m
TL=4 900 z=500 m
1000 TL=6 z=1000 m
800
700
800
DNI (Wh m-2)
600
DNI (Wh m-2)
600 500
400
400
300
200
200
100
0 0
0 2 4 6 8 10 12 14 16 18 20 22 24 0 5 10 15 20 25
Hora Hora
13. Components and non-dimensioanl indexes
Components of solar radiation in horizontal surface
IG IB cos ID
Clear sky or transparency index
IG
kt
I0
Difuse radiation fraction
ID
kd
IG
Beam radiation transmitance
IB
kb
I0
14. Estimation of beam solar radaition
Correlations to estimate difuse radiation fraction
G (1 kd )
Ib 1.0 0.09kt kt 0.22
sen( ) kd 0.9511 1.1604kt
0.165 kt 0.8
4.388kt 2 16.638kt 3 12.336kt 4 0.22 kt 0.8
Correlations to estimate beam transmitance
Ib kb I o kb 0.002 0.059kt 0.994kt 2 5.205kt 3 15.307kt 4 10.627kt 5
15. Measuring Solar Radiation:
Pyrheliometers EKO MS-54
Measures direct beam irradiance
Typically used for calibration transfers Middleton DN5
Normally defined with an opening angle of 5
If used in conjunction with pyranometers, the optical
flat protecting entrance should match the optical
material of the pyranometer domes
Relatively easy to characterize
4 major manufacturers:
EKO Instruments (Japan)
Eppley Instruments (USA)
Kipp & Zonen (Netherlands)
Middleton Solar [Carter Scott Design] (Australia)
Normally mounted on passive or active solar
tracking systems
16. Measuring Solar Radiation: Pyranometers
Tilted Irradiance
Most pyranometers use a thermopile as means of converting solar irradiance into
an electrical signal.
Silicon cell pyranometers are also available, but are not recommended by WMO.
Advantage of the thermopile is that it is spectrally neutral across the entire solar
spectrum (domes may have spectral dependencies).
Disadvantage is that the output is temperature dependent and the instruments
must ‘create’ a cold junction.
17. Measuring Solar Radiation: Silicon Pyranometers
Instrument’s spectral response is non-linear and does not match solar spectrum.
General calibrations are through comparison with pyranometers, therefore there
are spectral mismatch problems.
LiCor is the primary instrument manufacturer and recognizes these problems:
“The spectral response of the LI-200 does not include the entire solar
spectrum, so it must be used in the same lighting conditions as those under which
it was calibrated.”
–Pyranometer sensors are calibrated
against an Eppley Precision Spectral
Pyranometer (PSP) under natural daylight
conditions. Typical error under these
conditions is ±5%. (LiCor)
–Similar problems arise when using
sensors calibrated in one climate regime
and used in a different regime.
18. Rotating Shadowband Radiometer RSR2
LI-COR Terrestrial Radiation Sensors
Irradiance Inc. (www.irradiance.com)
LI-200 Pyranometer is a silicon photodiode
calibrated from LI-COR ±5%
RSR2 Head unit includes a moving shadowband
that momentarily casts a shadow over a LI-200
pyranometer
Motor controller contains circuit to control the
exact movement of shadowband LI-200 Pyranometer
Correction provided by Algorithm
Measurement:
Global Horizontal Irradiance
Diffuse Horizontal Irradiance
Calculation:
Direct Normal Irradiance
RSR2 Headunit RSR2 Motor Controller
20. Measurement recomendations
• Know exactly what temporal reference of the masurements
you are using (TSV, GMT, Local etc)
• Register with enough temporal resolution, almost 10 minutes
to register the dinamic of cloud transients.
• Follow BSRN recomendation for maintenance of instruments.
Cleaning every day radiometers, calibrate once per year each
instrument,…
• Secure the relation G=B cos θ + D. Some solar trackers have
embeded this filter in its program to activetes realtime alarms
when measurement is worng.
22. Satellite classification
According to the type of orbit :
Polar satellites: placed in polar
orbits, modifying its perspective
and distance to the earth. The
resolutions of these satellites are
around 1m to 1km.
Geostationary satellites: placed in the geostationary orbit that is, the place in the
space where the earth's attraction force is null. It is an unique circumference
where all the geostationary satellites are situated in order to cover the whole
earth's surface. The resolutions of these satellites are higher in the sub
satellite point on the equator, and go decreasing in all directions.
23. Meteosat Satellite coverage
Meteosat Prime Meteosat East
Spatial resolution 2.5 km at sub satellite, eg. About 3x4 km in Europe
Temporal resolution 1h.
Current Coverage: Meteosat Prime up to 1991-2005,
Meteosat East 1999 - 2006
24. Solar radiation derived from satellite images
Satellite to irradiance: general procedure
Meteosat – Goes - Mtsat
60’, 30’ or 15’ images in the visible
position assessement geometric
corrections – pixels averaging model to
obtain global irradiance
25. AOD (Aerosol Optical Depth estimations)
Estimations from MODIS (Moderate Resolution Imaging
spectroradiometer) on NASA’s Terra satellite
http://earthobservatory.nasa.gov/
AOD and water vapor vertical content estimations from satellite
27. Radiometric Databases
• Baseline Surface Radiation Network (BSRN)
• World radiation data centre (WRDC)
• Meteonorm
28. SSE
Radiometric Databases: SSE from NASA
http://eosweb.larc.nasa.gov/sse /
• Surface Meteorology and
• Solar Energy (SSE) Datasets
• And Web interface
• Monthly data
• Free upon
registration
Growing over the last 7 years to nearly 14,000 • 1ºx1º (120x120
users, nearly 6.4 million hits and 1.25 million
data downloads km) resolution
29. Solar radiation derived from satellite images
SWERA Project
The SWERA project provides easy access to high quality renewable energy resource information
and data to users all around the world. Its goal is to help facilitate renewable energy policy and
investment by making high quality information freely available to key user groups. SWERA
products include Geographic Information Systems (GIS) and time series data
30. Comercial data from satellite
• Irsolav
• Solemi (DLR)
• 3Tier
• Solargis
• ….
34. IrSOLaV activities
Ciemat promoted a spin-off company for solar resource
characterization services (www.irsolav.com). Thus IrSOLaV
interacts with the industry needs and supply data and
consulting services on solar resource and also collaborates
with Ciemat in R&D.
IrSOLaV and Ciemat develops R&D programs in the solar
resource field and collaborates with international scientific
groups (DLR, NREL, NASA, JRC, CENER, Universities…)
through European projects (COST project) or other initiatives
(Task 46 SHC/IEA)
Within Spain IrSOLaV and CIEMAT collaborates with
universities (UAL, UJA, UPN) and support the industry through
agreements for doing specific research on solar resource
knowledge (forecasting, model improvements, atmospheric
physics, etc)