Gravity-gradient stabilization (a.k.a. "tidal stabilization") is a method of stabilizing artificial satellites or space tethers in a fixed orientation using only the orbited body's mass distribution and gravitational field. The main advantage over using active stabilization with propellants, gyroscopes or reaction wheels is the low use of power and resources. It can also reduce or prevent the risk of propellant contamination of sensitive components. The idea is to use the Earth's gravitational field and tidal forces to keep the spacecraft aligned in the desired orientation. The gravity of the Earth decreases according to the inverse-square law, and by extending the long axis perpendicular to the orbit, the "lower" part of the orbiting structure will be more attracted to the Earth. The effect is that the satellite will tend to align its axis of minimum moment of inertia vertically. The first experimental attempt to use the technique on a human spaceflight was performed on September 13, 1966, on the US Gemini 11 mission, by attaching the Gemini spacecraft to its Agena target vehicle by a 100-foot (30 m) tether. The attempt was a failure, as insufficient gradient was produced to keep the tether taut. The technique was first successfully used in a near-geosynchronous orbit on the Department of Defense Gravity Experiment (DODGE) satellite in July 1967. It was first used for low Earth orbit and tested unsuccessfully for geosynchronous orbit in the Applications Technology Satellites ATS-2, ATS-4 and from 1966 until 1969. The lunar orbiter Explorer 49 launched in 1973 was gravity gradient oriented (Z axis parallel to local vertical). Long Duration Exposure Facility (LDEF) used this method for 3-axis stabilization; yaw about the vertical axis was stabilized. An example of gravity-gradient stabilization was attempted during NASA's TSS-1 mission in July 1992. The project failed because of tether deployment problems. In 1996 another mission, TSS-1R, was attempted but failed when the tether broke. Just prior to tether separation, the tension on the tether was about 65 N (14.6 lbs). (Wikipedia).
Applied ML 2020 - 08 - Gradient Boosting
Materials at https://www.cs.columbia.edu/~amueller/comsw4995s20/schedule/
From playlist Applied Machine Learning 2020
This video explains what information the gradient provides about a given function. http://mathispower4u.wordpress.com/
From playlist Functions of Several Variables - Calculus
Introduction to Gradient Descent
An introduction to gradient descent. See also https://youtu.be/W2pSn_t0KYs
From playlist gradient_descent
This video follows on from the discussion on linear regression as a shallow learner ( https://www.youtube.com/watch?v=cnnCrijAVlc ) and the video on derivatives in deep learning ( https://www.youtube.com/watch?v=wiiPVB9tkBY ). This is a deeper dive into gradient descent and the use of th
From playlist Introduction to deep learning for everyone
Physics - Mechanics: Gravity (5 of 20) The Effect of Earth's Rotation on Gravity
Visit http://ilectureonline.com for more math and science lectures! In this video I will calculate the effects of Earth's rotation on gravity.
From playlist PHYSICS 18 GRAVITY
The Gradient Operator in Vector Calculus: Directions of Fastest Change & the Directional Derivative
This video introduces the gradient operator from vector calculus, which takes a scalar field (like the temperature distribution in a room) and returns a vector field with the direction of fastest change in the temperature at every point. The gradient is a fundamental building block in vec
From playlist Engineering Math: Vector Calculus and Partial Differential Equations
Lecture 15 | Introduction to Robotics
Lecture by Professor Oussama Khatib for Introduction to Robotics (CS223A) in the Stanford Computer Science Department. Professor Khatib shows a short video about On the Run: The Leg Laboratory, then continues to lecture on Control. CS223A is an introduction to robotics which covers topi
From playlist Lecture Collection | Introduction to Robotics
Waves, Instabilities and Transport in Protoplanetary Disks by Heloise Meheut
DISCUSSION MEETING WAVES, INSTABILITIES AND MIXING IN ROTATING AND STRATIFIED FLOWS (ONLINE) ORGANIZERS: Thierry Dauxois (CNRS & ENS de Lyon, France), Sylvain Joubaud (ENS de Lyon, France), Manikandan Mathur (IIT Madras, India), Philippe Odier (ENS de Lyon, France) and Anubhab Roy (IIT M
From playlist Waves, Instabilities and Mixing in Rotating and Stratified Flows (ONLINE)
MATH2018 Lecture 2.3 Gradient and Directional Derivative
We introduce the concepts of the gradient and directional derivative, which tell us how a scalar field varies in space.
From playlist MATH2018 Engineering Mathematics 2D
Waves, Resonances and Instabilities in Stratified Rotating Flows (Lecture 1) by Patrice Le Gal
DISCUSSION MEETING WAVES, INSTABILITIES AND MIXING IN ROTATING AND STRATIFIED FLOWS (ONLINE) ORGANIZERS: Thierry Dauxois (CNRS & ENS de Lyon, France), Sylvain Joubaud (ENS de Lyon, France), Manikandan Mathur (IIT Madras, India), Philippe Odier (ENS de Lyon, France) and Anubhab Roy (IIT M
From playlist Waves, Instabilities and Mixing in Rotating and Stratified Flows (ONLINE)
Thomas Dubos: High performance climate modelling : mimetic finite differences, and beyond ?
Abstract: Climate models simulate atmospheric flows interacting with many physical processes. Because they address long time scales, from centuries to millennia, they need to be efficient, but not at the expense of certain desirable properties, especially conservation of total mass and ene
From playlist Numerical Analysis and Scientific Computing
Buoyancy Instabilities in Weakly Collisional Magnetized Plasmas by Prateek Sharma
GdR Dynamo 2015 PROGRAM LINK: www.icts.res.in/program/GDR2015 DATES : 01 Jun, 2015 - 12 Jun, 2015 VENUE : ICTS-TIFR, IISc campus, Bangalore DESCRIPTION : Dynamo or self-induced magnetic field generation in nature and laboratory is a very important area of research in physics, astrop
From playlist GdR Dynamo 2015
See also https://youtu.be/BYTi0RWp494 and https://youtu.be/vV_vIFL3LKU
From playlist gradient_descent
Self-similar gravitational collapse - Juhi Jang
Workshop on Recent developments in incompressible fluid dynamics Topic: Self-similar gravitational collapse Speaker: Juhi Jang Affiliation: University of Southern California Date: April 07, 2022 We discuss recent mathematical constructions of self-similar gravitational collapse for Newto
From playlist Mathematics
Download the free PDF http://tinyurl.com/EngMathYT A basic tutorial on the gradient field of a function. We show how to compute the gradient; its geometric significance; and how it is used when computing the directional derivative. The gradient is a basic property of vector calculus. NOT
From playlist Engineering Mathematics
Interface dynamics, incompressible fluids: Splash/Splat singularities – D. Córdoba – ICM2018
Partial Differential Equations Invited Lecture 10.16 Interface dynamics for incompressible fluids: Splash and Splat singularities Diego Córdoba Abstract: In this survey I report on recent progress in the study of the dynamics of the interface in between two incompressible fluids with dif
From playlist Partial Differential Equations
The Bizarre Paths of Groundwater Around Structures
Some unexpected issues for engineers who design subsurface structures... Worksafe BC video: https://youtu.be/kluzvEPuAug Next time you see a dam, retaining wall, caisson, or any other subsurface construction, there’s a good chance that engineers have had to consider how groundwater will
From playlist Civil Engineering
Buoyancy effects in dilute astrophysical plasmas by Prateek Sharma
Summer school and Discussion Meeting on Buoyancy-driven flows DATE: 12 June 2017 to 20 June 2017 VENUE: Ramanujan Lecture Hall, ICTS, Bengaluru Buoyancy plays a major role in the dynamics of atmosphere and interiors of planets and stars, as well as in engineering applications. This field
From playlist Summer school and Discussion Meeting on Buoyancy-driven flows
Olivier Soulard: Pourquoi l'eau tombe-t-elle d'un verre qu'on retourne
Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Mathematics Library: http://library.cirm-math.fr. And discover all its functionalities: - Chapter markers and keywords to watch the parts of your choice in the video - Videos enriched with abstracts, b
From playlist Mathematical Physics
Gravitation (4 of 17) Calculating Acceleration Due to Gravity (g)
Shows how to calculate the acceleration due to gravity. The equation is derived from Newton's second law and Newton's Law of universal gravitation. The acceleration due to gravity is the acceleration on an object caused by the force of gravitation. All bodies accelerate in a gravitati
From playlist Gravitation: Orbital Velocity, Orbital Period, Potential Energy, Kinetic Energy, Mass and Weight