Dislocation avalanches are a phenomenon observed in materials undergoing plastic deformation, particularly in crystalline solids. They refer to sudden and abrupt collective movements of dislocations, which are line defects in the crystal structure of materials. When stress is applied to a material, dislocations can move, leading to plastic deformation. However, under certain conditions, the movement of these dislocations can become unstable and result in a rapid, collective motion, akin to an "avalanche.

A Radiation Portal Monitor (RPM) is a type of security equipment used to detect and identify radioactive materials that may be transported through ports, borders, or other critical locations. These monitors are essential for preventing the illicit transport of nuclear materials and ensuring public safety. **Key Features of Radiation Portal Monitors:** 1. **Detection Capability**: RPMs are designed to detect gamma and neutron radiation emitted by radioactive isotopes.

The distance modulus is a mathematical expression used in astronomy to relate the distance of an object (like a star or a galaxy) to its absolute magnitude and apparent magnitude. It is a key concept in determining how far away celestial objects are based on their brightness.

The Distributed Annotation System (DAS) is a framework designed for the efficient integration and sharing of biological data, particularly annotations related to genomic features. DAS allows for the distribution and retrieval of biological data from multiple sources, enabling researchers to work with various datasets seamlessly. ### Key Components of DAS: 1. **Data Sources**: DAS servers host biological data and provide it through a standardized protocol. These servers can contain various types of data, including gene annotations, sequence information, and protein structures.

In the context of group theory, a **divisible group** is a particular type of abelian group (a group where the group operation is commutative) that satisfies a specific divisibility condition related to its elements.

A bitmap is a type of digital image that is composed of a grid of individual pixels, where each pixel can be set to a specific color. The term "bitmap" comes from the computer programming terminology, where "bit" refers to the smallest unit of data in computing, and "map" refers to a spatial representation of data.

Radical honesty is a concept and practice developed by psychologist Brad Blanton in the 1990s. It advocates for complete honesty in communication and interactions with others, emphasizing the importance of expressing one's true feelings, thoughts, and experiences without filtering or concealing them. The idea is that by being radically honest, individuals can eliminate the emotional burdens of deception, misunderstandings, and societal expectations.

A dodecahedral cupola is a type of geometric solid that is formed by combining two elements: a dodecahedron and a cupola. The dodecahedron is a polyhedron with 12 pentagonal faces, while a cupola is a type of dome shape that typically consists of a polygonal base and a set of triangular faces that converge at a point above the base.

As of my last knowledge update in October 2021, there is no widely recognized public figure or notable person named Donald Kreider. It's possible that he could be a private individual or perhaps someone who has gained prominence after that date.

In the context of semiconductors, a "donor" refers to an atom or impurity that is introduced into a semiconductor material (typically silicon or germanium) to create n-type (negative-type) semiconductor material. When donor atoms, which typically have five valence electrons (such as phosphorus, arsenic, or antimony), are added to the semiconductor lattice, they donate one extra electron that is not needed for bonding with the surrounding silicon atoms.

"Do Not Erase: Mathematicians and their Chalkboards" is a book that explores the relationship between mathematicians and their work environment, particularly focusing on the chalkboards that many of them use to express their ideas and solve problems. The book combines photographs of mathematicians with images of their chalkboards, showcasing the scribbles, diagrams, and equations that reflect their thought processes and the collaborative nature of mathematics.

The double affine braid group is an algebraic structure that arises in the study of braid groups in the context of affine Lie algebras and their representations. More specifically, it is an extension of the classical braid groups introduced by Emil Artin, with additional features that incorporate affine symmetry. ### Definition and Structure The double affine braid group \( \widetilde{B}_n \) can be seen as a generalization of the affine braid group.

The term "doublet state" is often used in the context of quantum mechanics, particularly when discussing the energy levels of systems with certain symmetries, such as electron configurations in atoms or molecules. In general terms, a doublet state refers to a quantum state characterized by two closely spaced energy levels or components.

Douglas Roche refers to a Canadian politician, author, and activist known for his work in disarmament and international relations. He served as a Member of the Parliament for the Progressive Conservative Party of Canada from 1972 to 1979 and held various roles, including that of a United Nations ambassador for disarmament. Roche has written several books and articles on peace, nuclear disarmament, and global security issues. His advocacy often focuses on promoting international cooperation and the importance of addressing nuclear threats.

The Global Drifter Program (GDP) is an international oceanographic initiative aimed at studying and monitoring ocean currents and related environmental conditions. It involves the deployment of drifting buoys, known as drifters, that float on the ocean's surface and are equipped with sensors to collect data on temperature, salinity, atmospheric pressure, and other oceanographic parameters.

Downward causation is a concept in philosophy of science and systems theory that refers to the idea that higher-level structures, properties, or entities can exert causal influence on lower-level ones. In simpler terms, it means that the behavior of a system as a whole can affect the individual components that make up that system. This concept contrasts with the more traditional view of causation, which typically emphasizes upward causation, where lower-level components influence higher-level aggregates.

As of my last knowledge update in October 2021, "Dragon reactor" isn't a widely recognized term in fields such as science, technology, or gaming. However, the term could refer to various things based on the context. In a hypothetical or fictional context, a "dragon reactor" might refer to a fictional power generation device powered by dragons, potentially found in video games, literature, or movies.

Radiochromic film is a type of dosimetric film used for measuring radiation exposure. It is primarily used in medical physics, radiation therapy, and radiation safety because of its ability to visually indicate radiation dose through changes in color. ### Key Characteristics of Radiochromic Film: 1. **Composition**: Radiochromic films are typically made from polymers that contain special dyes that change color when exposed to ionizing radiation.

A radio-controlled (RC) boat is a miniature model of a boat that can be operated from a distance using a remote control device. These boats are typically powered by electric motors, gas engines, or steam propulsion and can come in various sizes and styles, from small racing boats to large-scale replicas of real ships. RC boats operate on the principles of radio communication, where signals are sent from the transmitter (the remote control) to a receiver located within the boat.