P-completeIn computational complexity theory, a decision problem is P-complete (complete for the complexity class P) if it is in P and every problem in P can be reduced to it by an appropriate reduction. The notion of P-complete decision problems is useful in the analysis of: which problems are difficult to parallelize effectively, which problems are difficult to solve in limited space. specifically when stronger notions of reducibility than polytime-reducibility are considered.
Chemical reactionA chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive elements where both electronic and nuclear changes can occur.
Windows UpdateWindows Update is a Microsoft service for the Windows 9x and Windows NT families of the Microsoft Windows operating system, which automates downloading and installing Microsoft Windows software updates over the Internet. The service delivers software updates for Windows, as well as the various Microsoft antivirus products, including Windows Defender and Microsoft Security Essentials. Since its inception, Microsoft has introduced two extensions of the service: Microsoft Update and Windows Update for Business.
Windows 11Windows 11 is the latest major release of Microsoft's Windows NT operating system, released on October 5, 2021. It was a free upgrade to its predecessor, Windows 10 (2015), and is available for any Windows 10 devices that meet the new Windows 11 system requirements, but can also be installed on unsupported devices by bypassing the restrictions of system requirements.
Reaction rateThe reaction rate or rate of reaction is the speed at which a chemical reaction takes place, defined as proportional to the increase in the concentration of a product per unit time and to the decrease in the concentration of a reactant per unit time. Reaction rates can vary dramatically. For example, the oxidative rusting of iron under Earth's atmosphere is a slow reaction that can take many years, but the combustion of cellulose in a fire is a reaction that takes place in fractions of a second.
ButtressA buttress is an architectural structure built against or projecting from a wall which serves to support or reinforce the wall. Buttresses are fairly common on more ancient buildings, as a means of providing support to act against the lateral (sideways) forces arising out of inadequately braced roof structures. The term counterfort can be synonymous with buttress and is often used when referring to dams, retaining walls and other structures holding back earth.
Romanesque architectureRomanesque architecture is an architectural style of medieval Europe characterized by semi-circular arches. There is no consensus for the beginning date of the Romanesque style, with proposals ranging from the 6th to the 11th century, this later date being the most commonly held. In the 12th century it developed into the Gothic style, marked by pointed arches. Examples of Romanesque architecture can be found across the continent, making it the first pan-European architectural style since Imperial Roman architecture.
Arc flashAn arc flash is the light and heat produced as part of an arc fault, a type of electrical explosion or discharge that results from a connection through air to ground or another voltage phase in an electrical system. Arc flash is distinctly different from the arc blast, which is the supersonic shockwave produced when the uncontrolled arc vaporizes the metal conductors. Both are part of the same arc fault, and are often referred to as simply an arc flash, but from a safety standpoint they are often treated separately.
Perpendicular GothicPerpendicular Gothic (also Perpendicular, Rectilinear, or Third Pointed) architecture was the third and final style of English Gothic architecture developed in the Kingdom of England during the Late Middle Ages, typified by large windows, four-centred arches, straight vertical and horizontal lines in the tracery, and regular arch-topped rectangular panelling. Perpendicular was the prevailing style of Late Gothic architecture in England from the 14th century to the 17th century.
TraceryTracery is an architectural device by which windows (or screens, panels, and vaults) are divided into sections of various proportions by stone bars or ribs of moulding. Most commonly, it refers to the stonework elements that support the glass in a window. The purpose of the device is practical as well as decorative, because the increasingly large windows of Gothic buildings needed maximum support against the wind. The term probably derives from the tracing floors on which the complex patterns of windows were laid out in late Gothic architecture.
Electric arcAn electric arc (or arc discharge) is an electrical breakdown of a gas that produces a prolonged electrical discharge. The current through a normally nonconductive medium such as air produces a plasma, which may produce visible light. An arc discharge is initiated either by thermionic emission or by field emission. After initiation, the arc relies on thermionic emission of electrons from the electrodes supporting the arc. An arc discharge is characterized by a lower voltage than a glow discharge.
