The mean operation, often referred to as the "average," is a statistical measure used to summarize a set of numbers by finding their central point. Specifically, it is calculated by adding together all the values in a dataset and then dividing that sum by the total number of values.

Leigh Canham is a researcher and academic known for his work in the field of nanotechnology, particularly in the study of silicon and its properties at the nanoscale. He has contributed to understanding how nanoscale materials can be integrated into various applications, including electronics and biomedical devices. Canham's research often focuses on the optical and electronic properties of silicon nanocrystals and their potential uses.

Lateral earth pressure refers to the pressure exerted by soil upon a structure or retaining wall that is vertical or sloped. This pressure arises from the weight of the soil and is influenced by factors such as soil properties, wall friction, and whether the wall is moving or stationary. Understanding lateral earth pressure is essential in civil engineering, especially in designing retaining walls, basements, and other structures that interact with soil.

Mathcounts is a nationwide middle school mathematics competition in the United States aimed at enhancing students' mathematics skills and fostering a love for the subject. Founded in 1983, Mathcounts provides a platform for students in grades 6 through 8 to participate in individual and team competitions. The competition format typically includes: 1. **Chapter Competitions**: Schools hold local competitions, and the top students advance to chapter-level contests.

Kangeq is a former settlement located in Greenland. It is situated in the southern part of the country, near the capital city of Nuuk. Kangeq is notable for its historical significance and its proximity to the Nuuk Fjord. The settlement was established in the mid-20th century and was primarily inhabited by fishing and hunting communities. Over time, as populations shifted and urban areas developed, Kangeq saw a decline in its population and was eventually abandoned.

The Rayleigh dissipation function is a concept used in classical mechanics, particularly in the analysis of systems that experience non-conservative forces, such as friction or air resistance. It is a mathematical tool that helps to describe the energy lost in a system due to these non-conservative forces. In Lagrangian mechanics, the equations of motion for a system can be derived using the Lagrangian function, which is defined as the difference between the kinetic and potential energies of the system.

The number 140 is a positive integer that follows 139 and precedes 141. It can be represented in various forms in mathematics: 1. **Numeric Form**: 140 2. **Roman Numerals**: CXL (C for 100, X for 10, and L for 50) 3. **Binary**: 10001100 4. **Hexadecimal**: 8C 5.

Landslide classification refers to the categorization of landslides based on various characteristics such as their mechanism of movement, material type, rate of movement, and other geological or environmental factors. Proper classification is essential for understanding landslide behavior, risk assessment, and developing mitigation strategies. The main categories of landslides include: 1. **Type of Movement**: - **Falls**: Sudden detachment of rock or soil from a steep slope, leading to free fall.

155 mm artillery refers to a category of large-caliber artillery systems that fire projectiles with a diameter of 155 millimeters (approximately 6.1 inches). This caliber is widely used by many military forces around the world for its balance of range, explosive power, and accuracy. 155 mm artillery includes both towed and self-propelled howitzers, as well as mortars.