Concurrency (computer science)In computer science, concurrency is the ability of different parts or units of a program, algorithm, or problem to be executed out-of-order or in partial order, without affecting the outcome. This allows for parallel execution of the concurrent units, which can significantly improve overall speed of the execution in multi-processor and multi-core systems. In more technical terms, concurrency refers to the decomposability of a program, algorithm, or problem into order-independent or partially-ordered components or units of computation.
Animal sacrificeAnimal sacrifice is the ritual killing and offering of one or more animals, usually as part of a religious ritual or to appease or maintain favour with a deity. Animal sacrifices were common throughout Europe and the Ancient Near East until the spread of Christianity in Late Antiquity, and continue in some cultures or religions today. Human sacrifice, where it existed, was always much rarer. All or only part of a sacrificial animal may be offered; some cultures, like the ancient and modern Greeks, eat most of the edible parts of the sacrifice in a feast, and burnt the rest as an offering.
Sacrifice humainvignette|260px|Enfants de Llullaillaco, Sacrifice humain chez les Incas, Province de Salta (Argentine). Un sacrifice humain est un rite religieux qui a été pratiqué dans la plupart des civilisations, notamment au Néolithique et durant l'Antiquité, le plus souvent pour s'attirer les faveurs des dieux, par exemple pour conjurer la sécheresse, ou pour que les personnages importants tels que les souverains soient accompagnés dans l'au-delà par les sacrifiés.
Situation de compétitionUne situation de compétition (ou situation de concurrence, accès concurrent, concurrence critique, course critique, séquencement critique ; race condition en anglais, littéralement « situation de course »), est une situation caractérisée par un résultat différent selon l'ordre dans lequel agissent les acteurs du système. Le terme est plutôt employé à propos de programmes informatiques et de systèmes électroniques. C'est généralement considéré comme un défaut car source de panne ou de blocage.
Concurrency controlIn information technology and computer science, especially in the fields of computer programming, operating systems, multiprocessors, and databases, concurrency control ensures that correct results for concurrent operations are generated, while getting those results as quickly as possible. Computer systems, both software and hardware, consist of modules, or components. Each component is designed to operate correctly, i.e., to obey or to meet certain consistency rules.
Arbre binaire de rechercheEn informatique, un arbre binaire de recherche ou ABR (en anglais, binary search tree ou BST) est une structure de données représentant un ensemble ou un tableau associatif dont les clés appartiennent à un ensemble totalement ordonné. Un arbre binaire de recherche permet des opérations rapides pour rechercher une clé, insérer ou supprimer une clé.
Portable media playerA portable media player (PMP) (also including the related digital audio player (DAP)) is a portable consumer electronics device capable of storing and playing digital media such as audio, images, and video files. The data is typically stored on a compact disc (CD), Digital Versatile Disc (DVD), Blu-ray Disc (BD), flash memory, microdrive, SD cards or hard drive; most earlier PMPs used physical media, but modern players mostly use flash memory.
