Cardinal directionThe four cardinal directions, or cardinal points, are the four main compass directions: north, south, east, and west, commonly denoted by their initials N, S, E, and W respectively. Relative to north, the directions east, south, and west are at 90 degree intervals in the clockwise direction. The ordinal directions (also called the intercardinal directions) are northeast (NE), southeast (SE), southwest (SW), and northwest (NW). The intermediate direction of every set of intercardinal and cardinal direction is called a secondary intercardinal direction.
Role-based access controlIn computer systems security, role-based access control (RBAC) or role-based security is an approach to restricting system access to authorized users, and to implementing mandatory access control (MAC) or discretionary access control (DAC). Role-based access control is a policy-neutral access control mechanism defined around roles and privileges. The components of RBAC such as role-permissions, user-role and role-role relationships make it simple to perform user assignments.
Radio navigationRadio navigation or radionavigation is the application of radio frequencies to determine a position of an object on the Earth, either the vessel or an obstruction. Like radiolocation, it is a type of radiodetermination. The basic principles are measurements from/to electric beacons, especially Angular directions, e.g. by bearing, radio phases or interferometry, Distances, e.g. ranging by measurement of time of flight between one transmitter and multiple receivers or vice versa, Distance differences by measurement of times of arrival of signals from one transmitter to multiple receivers or vice versa Partly also velocity, e.
ReadingReading is the process of taking in the sense or meaning of letters, symbols, etc., especially by sight or touch. For educators and researchers, reading is a multifaceted process involving such areas as word recognition, orthography (spelling), alphabetics, phonics, phonemic awareness, vocabulary, comprehension, fluency, and motivation. Other types of reading and writing, such as pictograms (e.g., a hazard symbol and an emoji), are not based on speech-based writing systems.
Air navigationThe basic principles of air navigation are identical to general navigation, which includes the process of planning, recording, and controlling the movement of a craft from one place to another. Successful air navigation involves piloting an aircraft from place to place without getting lost, not breaking the laws applying to aircraft, or endangering the safety of those on board or on the ground. Air navigation differs from the navigation of surface craft in several ways; Aircraft travel at relatively high speeds, leaving less time to calculate their position en route.
High-frequency direction findingHigh-frequency direction finding, usually known by its abbreviation HF/DF or nickname huff-duff, is a type of radio direction finder (RDF) introduced in World War II. High frequency (HF) refers to a radio band that can effectively communicate over long distances; for example, between U-boats and their land-based headquarters. HF/DF was primarily used to catch enemy radios while they transmitted, although it was also used to locate friendly aircraft as a navigation aid.
PhonicsPhonics is a method for teaching people how to read and write an alphabetic language (such as English or Russian). It is done by demonstrating the relationship between the sounds of the spoken language (phonemes), and the letters or groups of letters (graphemes) or syllables of the written language. In English, this is also known as the alphabetic principle or the alphabetic code. While the principles of phonics generally apply regardless of the language or region, the examples in this article are from General American English pronunciation.
Far-left politicsFar-left politics, also known as the radical left or extreme left, are politics further to the left on the left–right political spectrum than the standard political left. The term does not have a single, coherent definition; some scholars consider it to represent the left of social democracy, while others limit it to the left of communist parties. In certain instances—especially in the news media—far left has been associated with some forms of authoritarianism, anarchism, communism, and Marxism, or are characterized as groups that advocate for revolutionary socialism and related communist ideologies, or anti-capitalism and anti-globalization.
Inertial navigation systemAn inertial navigation system (INS) is a navigation device that uses motion sensors (accelerometers), rotation sensors (gyroscopes) and a computer to continuously calculate by dead reckoning the position, the orientation, and the velocity (direction and speed of movement) of a moving object without the need for external references. Often the inertial sensors are supplemented by a barometric altimeter and sometimes by magnetic sensors (magnetometers) and/or speed measuring devices.
