"The Darkest Hour" is a 2011 science fiction thriller film directed by Chris Gorak. The movie is set in Moscow, where a group of young American tourists find themselves stranded in the city after a mysterious alien invasion. These extraterrestrial beings are invisible and can kill humans with a touch, creating a tense and suspenseful atmosphere throughout the film.

As of my last knowledge update in October 2021, there isn't any widely recognized figure or topic specifically known as "Rajesh Maingi." He may be a private individual, or his relevance could have emerged after that date. If you have additional context or details about who he is or the area you are referring to (e.g.

The André plane, also known as the André–Tamagawa plane, is a concept in algebraic geometry that arises in the context of p-adic geometry and the study of rational points on algebraic varieties. It was introduced by the mathematician Yves André as part of his work on the geometry of numbers and the theory of motives.

The Darcy number (\(Da\)) is a dimensionless number used in the study of fluid flow through porous media. It quantifies the ratio of the permeability of the porous medium to the square of the characteristic length scale, which is often related to the size of the pores.

The Eckert number (Ec) is a dimensionless quantity used in fluid mechanics and heat transfer to characterize the relative importance of thermal energy storage to the convective heat transfer in a flowing fluid. It is defined as the ratio of kinetic energy to thermal energy associated with the temperature changes in the fluid.

The Ekman number (Ek) is a dimensionless quantity in fluid dynamics that characterizes the relative importance of the viscous forces to the Coriolis forces in a rotating fluid system.

In the context of aircraft navigation and aerodynamics, the term "F-plane" refers to a specific type of reference plane used in flight dynamics and control theory. It is typically part of the formulation of aircraft equations of motion. The F-plane is aligned with the flight path of the aircraft and is used to analyze how the aircraft responds to various forces and moments during flight.

Flow meter error refers to the discrepancy between the measured flow rate as indicated by a flow meter and the actual flow rate of a fluid passing through the meter. This error can arise from various factors, including: 1. **Calibration Error**: If the flow meter is not properly calibrated, it may provide inaccurate readings. Regular calibration is necessary to ensure accuracy. 2. **Installation Effects**: Poor installation can lead to errors.

Free molecular flow refers to a regime of gas flow where the mean free path of gas molecules is much larger than the characteristic dimensions of the system through which the gas is flowing. In this condition, gas molecules travel between collisions without interacting with other molecules, often behaving as if they are in a vacuum. ### Key Characteristics of Free Molecular Flow: 1. **Mean Free Path**: This is the average distance a molecule travels between successive collisions.

The Haynes similitude principle, often referred to simply as "similitude," is a concept used primarily in fluid dynamics and related fields. It is a method that allows engineers and scientists to predict the behavior of one fluid system based on the behavior of another fluid system that is similar in certain respects. The principle is based on the idea that certain dimensionless parameters can be used to create relationships between different systems.

Rana X. Adhikari is a physicist known for his work in the fields of gravitational physics and astrophysics. He has contributed to research on gravitational waves, the study of black holes, and the dynamics of complex systems in astrophysics. Adhikari is also associated with institutions focusing on experimental physics, including work related to the Laser Interferometer Gravitational-Wave Observatory (LIGO).

The Marker-and-Cell (MAC) method is a numerical technique used to solve fluid dynamics problems, particularly for simulating incompressible flows. It was developed in the early 1970s and is widely applied in computational fluid dynamics (CFD) due to its effectiveness in handling complex boundary conditions.

The Okubo–Weiss parameter is a measure used in fluid dynamics, particularly in the study of turbulent flows, to analyze the stability and behavior of vortical structures in fluid motion. It helps to distinguish between different types of fluid flow by quantifying the balance between strain and rotation in the flow field.

Patch dynamics is a concept that arises in various fields, including physics, ecology, and systems biology. In the context of physics, it often pertains to the study of dynamic systems that can be modeled as composed of distinct "patches" or regions, each of which can have different properties or behaviors while interacting with one another.

Preferential concentration refers to a phenomenon in fluid dynamics and particle dynamics, particularly in suspensions and aerosols, where particles are not uniformly distributed throughout a flow. Instead, they tend to cluster or align preferentially in certain regions of the flow field, often in areas of low vorticity or high shear. This clustering can occur due to a variety of factors, including the interplay between the particles' inertial effects and the flow field's characteristics.

Standard sea-level conditions, often referred to as standard atmospheric conditions or International Standard Atmosphere (ISA), are a set of idealized atmospheric conditions defined for the purpose of measurement and comparison. The conditions are typically specified at sea level and are assumed to be: - **Temperature:** 15 degrees Celsius (59 degrees Fahrenheit) - **Pressure:** 1013.25 hPa (hectopascals), or 1013.25 millibars, or 29.

Transition modeling is a statistical and computational approach used to represent and analyze the changes (or transitions) between different states or conditions in a system over time. This concept is widely applied in various fields, such as economics, ecology, engineering, social sciences, and health sciences, to model dynamic processes. Here are some key aspects of transition modeling: 1. **State Space**: A transition model typically defines a finite or infinite set of states that a system can occupy.

Vortex stretching is a phenomenon in fluid dynamics that occurs in turbulent flows. It refers to the process by which a vortex line, or a thin filament of vorticity, is stretched as the surrounding fluid moves. This stretching leads to an increase in the strength and intensity of the vortex, ultimately resulting in the formation of smaller vortices and a more complex flow structure.