Prenex normal formA formula of the predicate calculus is in prenex normal form (PNF) if it is written as a string of quantifiers and bound variables, called the prefix, followed by a quantifier-free part, called the matrix. Together with the normal forms in propositional logic (e.g. disjunctive normal form or conjunctive normal form), it provides a canonical normal form useful in automated theorem proving. Every formula in classical logic is logically equivalent to a formula in prenex normal form.
Impact evaluationImpact evaluation assesses the changes that can be attributed to a particular intervention, such as a project, program or policy, both the intended ones, as well as ideally the unintended ones. In contrast to outcome monitoring, which examines whether targets have been achieved, impact evaluation is structured to answer the question: how would outcomes such as participants' well-being have changed if the intervention had not been undertaken? This involves counterfactual analysis, that is, "a comparison between what actually happened and what would have happened in the absence of the intervention.
Video game artVideo game art is a specialized form of computer art employing video games as the artistic medium. Video game art often involves the use of patched or modified video games or the repurposing of existing games or game structures, however it relies on a broader range of artistic techniques and outcomes than artistic modification and it may also include painting, sculpture, appropriation, in-game intervention and performance, sampling, etc. It may also include the creation of art games either from scratch or by modifying existing games.
Double negationIn propositional logic, double negation is the theorem that states that "If a statement is true, then it is not the case that the statement is not true." This is expressed by saying that a proposition A is logically equivalent to not (not-A), or by the formula A ≡ ~(~A) where the sign ≡ expresses logical equivalence and the sign ~ expresses negation. Like the law of the excluded middle, this principle is considered to be a law of thought in classical logic, but it is disallowed by intuitionistic logic.
Affirmation and negationIn linguistics and grammar, affirmation (abbreviated ) and negation () are ways in which grammar encodes positive and negative polarity into verb phrases, clauses, or other utterances. An affirmative (positive) form is used to express the validity or truth of a basic assertion, while a negative form expresses its falsity. For example, the affirmative sentence "Jane is here" asserts that it is true that Jane is currently located near the speaker.
Conjunctive normal formIn Boolean logic, a formula is in conjunctive normal form (CNF) or clausal normal form if it is a conjunction of one or more clauses, where a clause is a disjunction of literals; otherwise put, it is a product of sums or an AND of ORs. As a canonical normal form, it is useful in automated theorem proving and circuit theory. All conjunctions of literals and all disjunctions of literals are in CNF, as they can be seen as conjunctions of one-literal clauses and conjunctions of a single clause, respectively.
Noun phraseA noun phrase, or nominal (phrase), is a phrase that has a noun or pronoun as its head or performs the same grammatical function as a noun. Noun phrases are very common cross-linguistically, and they may be the most frequently occurring phrase type. Noun phrases often function as verb subjects and objects, as predicative expressions and as the complements of prepositions. Noun phrases can be embedded inside each other; for instance, the noun phrase some of his constituents contains the shorter noun phrase his constituents.
PHPPHP is a general-purpose scripting language geared towards web development. It was originally created by Danish-Canadian programmer Rasmus Lerdorf in 1993 and released in 1995. The PHP reference implementation is now produced by the PHP Group. PHP was originally an abbreviation of Personal Home Page, but it now stands for the recursive initialism PHP: Hypertext Preprocessor. PHP code is usually processed on a web server by a PHP interpreter implemented as a module, a daemon or a Common Gateway Interface (CGI) executable.
NominalizationIn linguistics, nominalization or nominalisation is the use of a word that is not a noun (e.g., a verb, an adjective or an adverb) as a noun, or as the head of a noun phrase. This change in functional category can occur through morphological transformation, but it does not always. Nominalization can refer, for instance, to the process of producing a noun from another part of speech by adding a derivational affix (e.g., the noun legalization from the verb legalize), but it can also refer to the complex noun that is formed as a result.
