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104 [a] The Rockwell B-1 Lancer [b] is a supersonic variable-sweep wing, heavy bomber used by the United States Air Force. It has been nicknamed the "Bone" (from "B-One"). [2] [3] It is one of the Air Force's three strategic bombers, along with the B-2 Spirit and the B-52 Stratofortress, as of 2024. Its 75,000-pound (34,000 kg) payload is the ...
- 23 December 1974; 48 years ago
- 1973–1974, 1983–1988
Trinity was the code name of the first detonation of a nuclear weapon, conducted by the United States Army at 5:29 a.m. MWT[a] (11:29:21 GMT) on July 16, 1945, as part of the Manhattan Project. The test was of an implosion-design plutonium bomb, nicknamed the "gadget", of the same design as the Fat Man bomb later detonated over Nagasaki, Japan ...
- July 16, 1945, (78 years ago)
- Trinity Site, New Mexico
Quantum mechanics. Quantum entanglement is the phenomenon of a group of particles being generated, interacting, or sharing spatial proximity in such a way that the quantum state of each particle of the group cannot be described independently of the state of the others, including when the particles are separated by a large distance.
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A sigmoid function is a bounded, differentiable, real function that is defined for all real input values and has a non-negative derivative at each point and exactly one inflection point. A sigmoid "function" and a sigmoid "curve" refer to the same object.
In general, a sigmoid function is monotonic, and has a first derivative which is bell shaped. Conversely, the integral of any continuous, non-negative, bell-shaped function (with one local maximum and no local minimum, unless degenerate) will be sigmoidal. Thus the cumulative distribution functions for many common probability distributions are sigm...
Many natural processes, such as those of complex system learning curves, exhibit a progression from small beginnings that accelerates and approaches a climax over time. When a specific mathematical model is lacking, a sigmoid function is often used. The van Genuchten–Gupta model is based on an inverted S-curve and applied to the response of crop yi...
Mitchell, Tom M. (1997). Machine Learning. WCB McGraw–Hill. ISBN 978-0-07-042807-2.. (NB. In particular see "Chapter 4: Artificial Neural Networks" (in particular pp. 96–97) where Mitchell uses the...Humphrys, Mark. "Continuous output, the sigmoid function". Archived from the original on 2022-07-14. Retrieved 2022-07-14.(NB. Properties of the sigmoid, including how it can shift along axes and h..."Fitting of logistic S-curves (sigmoids) to data using SegRegA". Archivedfrom the original on 2022-07-14.
Young's modulus is defined as the ratio of the stress (force per unit area) applied to the object and the resulting axial strain (displacement or deformation) in the linear elastic region of the material. Although Young's modulus is named after the 19th-century British scientist Thomas Young, the concept was developed in 1727 by Leonhard Euler.
The moment of inertia, otherwise known as the mass moment of inertia, angular/rotational mass, second moment of mass, or most accurately, rotational inertia, of a rigid body is a quantity that determines the torque needed for a desired angular acceleration about a rotational axis, akin to how mass determines the force needed for a desired accele...
On 17 October 2022, a Russian Su-34 fighter-bomber crashed into the courtyard of a residential apartment complex in the Russian city of Yeysk during a training flight, setting two blocks on fire. 15 people were killed and 19 were treated in hospital. A school was evacuated.
