JAOMAD Glossary N:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Intro
N—Thermocouple type for Omegalloy™(Nicrosil-Nisil); also: n(lowercase) in math is abbreviation "nano-" for 10-9, once called milli-micron (mµ).
N-ISDN—Narrowband Integrated Services Digital Network.
NA—Numerical Aperture; light gathering ability of a fiber, defining maximum angle to fiber axis at which light will be accepted and propagated through that fiber; also: describes angular spread of light from central axis, as in exiting fiber, emitting from source, or entering detector; also: North America; also: Not Applicable.
NA Mismatch Loss—In fiber optics, loss of power at joint that occurs when transmitting half has NA greater than that of receiving half, as when coupling light from source to fiber, from fiber to fiber, or from fiber to detector.
NAC—Network Access Control; umbrella term for managing access to a network; governs user authentication and user permissions as well as security measures (firewalls, anti-spyware, antivirus, etc.).
NACCB—(National Accreditation Council for Certification Bodies).
NACE—(National Association of Corrosion Engineers).
NAI—Normally Attended Installations (such as offshore).
NAK—Negative AcKnowledgement; indicates that previous transmission block was in error and that receiver is ready to accept retransmission of the erroneous block; also: the "not ready" reply to station selection in multipoint operation, or to initialization sequence in point-to-point operation.
NAMUR—(Norman Ausschultz für Messung Und Regelung); committee founded in 1949 by several large chemical companies from Germany, The Netherlands, and Switzerland to standardize industrial practices in process measurement and control; subcommittee published set of guidelines for structured batch control in 1986, accepted throughout European chemical industry with strong influence worldwide; looks at batch automation from process activity viewpoint, and views activities as charge, mix, heat/cool, etc. as repeatable across many processes and industries, so then presents hierarchy of structures, terminology, and definitions for classifying production facilities, processing equipment, recipe structure, as well as batch operational sequences and phases.
NAND—Not AND, an inverted AND gate.
Nanometer (nm)—Unit in which wavelengths of light are expressed; one nanometer is one-billionth of one meter.
Nanosecond—One billionth of one second.
Nanotechnology—Science of developing materials at atomic and molecular level in order to imbue them with special electrical and chemical properties; deals with devices typically less than 100 nanometers in size, is expected to make significant contribution to fields of computer storage, semiconductors, biotechnology, manufacturing and energy; a nanometer is one billionth of a meter; a human hair is roughly 100,000 nanometers wide.
Narrowband Channels—Sub-voice grade communication channels characterized by a speed range 0f 100 to 200 bps.
Narrowcasting—terms multicast and narrowcast are often used interchangeably, although narrowcast usually refers to the business model whereas multicast refers to the actual technology used to transmit the data; see Multicasting.
NAS—Network Attached Storage; see definition.
NAT—Network Address Translation; ability to show one Internet IP address to the world while concealing IP addresses of the computers on the network; often used by small system routers to protect protocol-level attacks on Windows systems because outsiders see only router itself, which doesn't run Windows; unlike serious firewalls, won't protect you against many sophisticated network attacks.
Natural Language—Any naturally evolved human language; usually in comparison to a programming language.
NBR—Nitrile Butadiene-acrylonitrile Rubber.
NBS—(National Bureau of Standards); now NIST.
NC—Normally Closed (usually switch or relay condition), allows flow until energized; also: in Numeric Control, technique of operating machine tools or similar equipment in which motion is generated in response to numerically ordered commands, typically from computer devices; also: Network Computer, very inexpensive PC-like which is for link to networks and contains minimum resident software, no hard drives, but downloads whatever applications needed for task at hand only for as long as needed, contrasting with PCs which must have everything resident within to function.
NCAICM—(National Center for Advanced Information Components Manufacturing); formed to develop considerably improved, high resolution, flat panel displays and advanced information components; participants include Los Alamos and Livermore Labs, 39 industrial partners, and eight universities.
NCAP—Network-Capable Applications Processor; provides “translation” of smart-transmitter data to/from network by STIM and TEDS, as defined by IEEE-P1451; see STIM, TEDS, IEEE-P1451.
NCB—National Certification Body (USA); tests electrical equipment for safety standards to meet compliance requirements relevant to International Electrotechnical Committee IEC standard; there are 34 certification bodies in 29 countries worldwide, five of which are in U.S.; reciprocal certification among various countries reduce delays waiting for duplicate testing in each country before product release there; see also CB.
NCGA—(National Computer Graphics Association).
NCMS—(National Center for Manufacturing Sciences) in USA.
NCS—Network Control System; see definition.
NCSD—National Cyber Security Division of Department of Homeland Security (DHS), [USA]
NDIS—Network Driver Interface Specification; standard created by Microsoft® for writing hardware independent drivers for third party Ethernet adapters.
nDt—Refractive index of substance using sodium light at specific temperature.
Electrical Code (USA) of regulations for construction and installation of
electrical wiring and apparatus, established by the NFPA, suitable for mandatory
application by wide range of state and local authorities; classifications
Class I—Hazardous vapors,
Class II—Combustible dust,
Class III—Combustible fibers & particulated,
Division 1—Flammable/combustible atmosphere generally present,
Division 2—Flammable/combustible atmosphere present under abnormal conditions,
Group C—Ethylene, ether, other,
Group D—Hydrocarbons (e.g. gasoline, natural gas),
Group E—Electrically conductive dust (e.g. magnesium),
Group F—Coal or coke dust,
Group G—Agricultural dust.
NECQ—National Electronics Component Qualification System (US).
Negative Letterspacing—In typographical composition of screen displays and printing, the subtraction of space between characters individually or en masse; see Kerning.
Negative Temperature Coefficient—Decrease in resistance with an increase in temperature.
NEK—(Norsk Elektroteknisk Komite); Norwegian member of IEC.
Electrical Manufactures Association); US trade association of electrical
equipment manufactures which develops many manufacturing specifications,
included are cabinet ratings such as:
NEMA 1—Dust resistant general purpose,
NEMA 2—Drip tight,
NEMA 3—Splash proof (weather resistant),
NEMA 4—High pressure hose proof,
NEMA 5—Dust tight,
NEMA 7—Hazardous indoor (NEC Class I Groups A,B,C,D),
NEMA 8—Hazardous indoor/outdoor (NEC Class I Groups A,B,C,D),
NEMA 9—Hazardous indoor/outdoor (NEC Class II Groups E,F,G),
NEMA 10—MSHA 30 CFR part 18,
NEMA 11—General purpose drip & corrosion resistant from liquids & gases,
NEMA 12—General purpose indoor use drip/dust/rust resistant,
NEMA 13—General purpose resistant to dust/rust & spraying of water/oil/noncorrosive liquids.
IEC enclosure classes equivalent to NEMA ratings: IP10 = NEMA 1, IP11 = NEMA 2, IP14/54 = NEMA 3/13, IP52 = NEMA 5/12, IP56 = NEMA 4, IP67 = NEMA 7.
NEMKO—(Norges Elektriske Materiellkontroll); Norwegian certification and testing laboratory for testing equipment of different vendors to some common standard.
NEPSI—(National Supervision and Inspection Centre for Explosion Protection and Safety of Instrumentation); Chinese certification and testing laboratory for testing equipment of different vendors to some common standard.
NERC—(North American Electric Reliability Corporation); self-regulatory organization that relies on the diverse and collective expertise of industry participants to improve the reliability and security of the bulk power system in North America.
NeSSI—New Sampling/Sensor Initiative; collaborative open industry-wide initiative, with most of the work being done by industrial companies in chemical and petrochemical fields (both vendors and end-users), aimed at developing and promoting a new technology for how process analyzers and sample conditioning systems are designed, constructed, and used within Industry; heart of the technology is standardized modular surface-mount architecture.
Nesting—To embed programming subroutine or data block in larger routine or data block; organization of data in hierarchical structures for greater efficiency in storing and processing repetitive elements, thereby identical elements need be represented only once in data base.
NetBEUI—NetBIOS Extended User Interface; primary protocol used by Windows for Workgroups, supported in all of Microsoft’s network products.
NetBIOS—Network Basic Input/Output System; high level session-layer interface used by applications as communications interface to PC-DOS applications.
NetPC—Network PC; which is more like compact PC rather than network computer (NC), and contains minimum resident software, no hard drive, can download whatever applications needed for task at hand only for as long as needed, contrasting with PCs which must have everything resident within itself to function.
Net Present Value—Calculation of time value of money over extended periods.
Network—Interconnected group of nodes; series of points, nodes, or stations connected by communications channels; assembly of equipment through which connections are made between data stations; in electrical pneumatic or hydraulic circuit, any combination of circuit elements; also: in configuration standards, interconnected set of IEC 61131-3 programming language elements; also: in microprocessing, electronic means of allowing more than one person at a time to corrupt, trash, and otherwise cause permanent damage to useful information. J
Network Attached Storage (NAS)—Hard disk storage that is set up with its own network address rather than being attached to a central computer that is serving applications to a network's workstation users; this way both application programming and files can be served faster because they are not competing for the same processor resources; attached to a local area network (typically, an Ethernet network) and assigned an IP address.
Network Architecture—Set of design principles, including organization of functions and description of data formats and procedures, used as basis for design and implementation of network (ISO).
Network Control System (NCS)—Called by some “Hybrid Control System;” autonomous controllers connected via internet communication (generally isolated) to each other peer-to-peer with a commercial-off-the-shelf PC as a workstation.
Network Interface Card (NIC)—Network adapter to control transmission and receiving of data at the data link level (layers 1 and 2 of the OSI model); plugs into bus of both user machines (clients) and servers in a local area network (LAN) and wired to a network hub, switch or router, typically using twisted wire pair cables, although optical fibers may be used for very fast connections.
Network Intrusion Detection Sensor (NIDS)—Cyber security device that sits on network and evaluates data traveling over it; typically connects to Switched Port Analyzer (Roving Analysis Port) on switches, so a single sensor can evaluate all or most of the traffic on a subnet to match up data related to a hacking exploit called a signature, and may have more than 1,000 signatures, but each new exploit typically requires the development of a new signature.
Network Layer—In digital communication, layer three in OSI model; the logical network entity that services transport layer; responsible for ensuring that data passed to it from transport layer is routed and delivered through the network.
Network Management (NM)—In FOUNDATION Fieldbus technology, permits FOUNDATION Network Manager (NMgr) entities to conduct management operations over network by using Network Management Agents (NMAs); each Network Management Agent (NMA) is responsible for managing communications within a device; NMgr and NMA communicate through use of Fieldbus Messaging Specification (FMS) and Virtual Communications Relationship (VCR).
Network Time Protocol (NTP)—TCP/IP protocol used to synchronize realtime clock in computers, network devices and other electronic equipment that is time sensitive; used as well to maintain correct time in NTP-based wall and desk clocks; Universal Time Coordinated (UTC) can be obtained over the Internet, which contains numerous primary and secondary time servers, or it can be acquired from stand-alone devices that receive atomic clock signals from the GPS system [visit www.ntp.org.]; See UTC.
Network Topology—Physical and logical relationship of nodes in a network; schematic arrangement of links and nodes of a network; networks are typically star, ring, tree, or bus topology, or some combination.
Neural Computing—Adapts to repeated examples in order to recognize patterns; not based on algorithms; mathematical mapping between repeatable cause and effect is learned through pattern recognition; cannot handle constraints and cannot optimize.
Neural Network Computer—Has no CPU, no memory, a learning algorithm, not necessarily a state machine, each element (a neuron) is a system with transfer function using filter with weight for each input.
Neural Network—Processing architecture derived from models of neuron interconnections of the brain; unlike typical computers, neural networks incorporate form of learning, rather than programming, and function parallel rather than sequential processing.
Neutral Zone—Increment through which input signal to device or system is varied before action is detected; expressed as percentage of input span; see Differential.
Newsgroups—Somewhat like BBS, these are discussion groups on the Internet on global scale.
NFC—Norwegian Fieldbus Consortium; also: French standards organization.
NFM—NearField Monitor; one of several small audio monitors mounted in close proximity to listener(s) so ratio of direct sound waves to waves reflected from surfaces in room are quite high, meaning that sound is relatively unaffected by room acoustics.
NFPA—(National Fire Protection Association); also: (National Fluid Power Association).
NFS—Network File Server; TCP/IP extension allowing files on remote nodes of network to appear locally connected.
Nibble—In digital computer communications, one half of a byte, four bits.
NIC—Network Interface Card; see definition.
NiCad—Nickel Cadmium; usually plating on brass screws.
NIC—Network Interface Card.
Nicrosil/nisil—Nickel chrome/nickel silicone thermal alloy used to measure high temperatures.
NIDS—Network intrusion detection sensor; see definition.
NIMBY—Not In My Backyard; principle that almost everyone wants new technology, services, etc. without any inconvenience; such as instant, unfettered communications over fat pipes, but want associated transmission towers to be located only on the moon, or at least in someone else's backyard where they're out of sight but not out of range.
NIOSH—(National Institute for Occupational Safety and Health); independent U.S. federal agency charged with performing research on occupational disease and injury.
NIRD—Near InfraRed Device, such as spectrophotometer analyzer.
NIST—(National Institute of Science and Technology); formerly NBS, U.S. government agency that provides standard reference materials and calibration services; NIST certified instruments are calibrated at NIST, whereas NIST traceable instruments are factory calibrated against NIST certified standards.
NM—Network Management; see definition.
nm—Nanometer, one billionth of a meter.
NMOS—N-channel Metal Oxide Semiconductor.
NMR(R)—Normal Mode Rejection Ratio, see definition.
NN—Neural Network; see definition.
NNC—Neural Network Computer; has no CPU, no memory, has learning algorithm, is not necessarily a state machine, each element (neuron) is a system with transfer function using filter with weight for each input.
NNI—(Nederlands Normalisatie-Instituut); standards group in The Netherlands and member of IEC.
NO—Normally Open (usually in reference to switch or relay condition); does not allow flow unless energized.
Node—Point of interconnection to some network; normally point at which a number of terminals or tail circuits attach to network.
Noise—In electrical signals, the RMS, a peak-to-peak alternating current component of dc signal in absence of measurand; in general, any unwanted electrical interference or other disturbances superimposed on signal wires which will obscure information content; noise comes from the very soul of the universe and occurs across the entire spectrum of electromagnetic communications; any piece of electronics introduced into a circuit will introduce noise, but usually "active" powered devices such as transistors, diodes, and integrated circuits are the noticeable offenders; see Electrical Noise.
NOM—Natural Organic Materials; monitored in water supplies, especially for their reaction to disinfectant, which can cause damaging byproducts; also: (Normas Oficiales Mexicanas) mark for products that are certified to the Mexican standard for electrical products.
Non-impact Printer—Electronic device like copier, laser or inkjet printer that creates images on (usually paper) surface without contacting it.
Non-isolated Transmitters―Type 2 or type 3 analog (4-20mA) transmitters used in an ungrounded circuit
Non-linear—In video development, ability to edit scenes together in any order and make changes to previous edit decisions (compare with Linear).
Non-modal—Not mode oriented; a non-modal operation moves from one situation to another without apparent mode switching; compare Modal.
Non-modal Window—In computer programming, a pop-up window within a program which does not cause that program to pause or stop while it is opened; compare with Modal Window.
Non-procedural Programming Language—Computer programming language used to express parameters of problem rather than steps in solution, for example, report writer or sort specification languages; see Procedural Programming Language.
Non-switched Line—Communications link which is permanently installed between two points; also called leased line or private line.
Non-tracking—Insulating material with dielectric characteristics sufficient to resist carbonizing or deterioration when subject to rated voltage and design conditions in electrical power (or signal) lines.
Non-transparent Mode—Transmission of characters in defined character format, such as ASCII or EBCDIC, in which all defined control characters and control character sequences are recognized and treated as such.
Normal Mode Rejection Ratio—Ability of instrument to reject interference, usually of the line frequency (50-60 Hz), across its input terminals (vs. Common Mode).
NOR—Not OR, an inverted OR gate.
NOR Flash—Acts like a NOR gate and continues to be the technology of choice for embedded applications requiring a discrete non-volatile memory device to allow for both direct code execution and data storage in a single memory product.
NOS—Network Operating System.
Notch Filter—In digital signal processing (DSP), filter that attenuates signals in certain frequency band and passes all others.
NOx—Nitrogen Oxides, a consideration in EPA (U.S.) regulations; compounds formed by oxidation of atmospheric nitrogen under high energy conditions, released primarily from burning fossil fuels.
NPDES—National Pollutant Discharge Elimination System; U.S. federal permitting program for discharging effluent to surface waters, required under Clean Water Act; over 15,000 municipal and 48,000 industrial facilities report monthly on amount and content of discharge.
NPE—Normalized Prediction Error method of measuring process control loop tuning effectiveness.
NPL—National Priorities List of hazardous waste sites in U.S. which will be addressed by the Comprehensive Environmental Response, Compensation and Liability Act.
NPO—Negative-Positive-0 (zero) drift capacitor which makes it very stable; has negative temperature coefficient causing little capacitance change over temperature as bias.
NPT—National Pipe Taper (pipe thread specification); also: Network Planning Terminal; also: Planning Tool; also: Plated Through (hole; printed circuit board, PCB); also: Non Punch Through (type of Insulated Gate Bipolar Transistor); also: Normal Pressure and Temperature; also: (Norwegian Post and Telecommunications Authority); also: Power Turbine Speed.
NPV—Net Present Value, see definition.
NRE—Non Recurring Engineering.
NREN—National Research & Education Network (U.S.).
NREP—(National Registry of Environmental Professionals); U.S. organization designed to implement programs for recognition of quality and certification of environmental professionals.
NRFT—Not Right First Time; mathematical inverse of Right first Time (RFT), an error rate measuring technique of effectiveness for QA/QC.
NRTL—(Nationally Recognized Testing Laboratory); program which is part of OSHA’s Directorate of Technical Support to recognize private sector testing laboratories, designating that those laboratories have met necessary qualifications specified in regulations for that program; leads to NRTLs from different international organizations to accept common standards with same testing regimen.
NRZ—Non Return to Zero; pulses in alternating directions for successive 1 bits; no change from existing bias for 0 bits.
NRZI—Non Return to Zero Inverted.
NSAI—(National Standards Authority of Ireland).
NSAP—Network Service Access Point.
NSAPI - NetScape API; computer programming interface on Netscape's Web Server which has function calls so that web pages can invoke programs on server, typically to access data in a database as alternative to using CGI scripts on Netscape web servers
NSF—(National Sanitation Foundation), non-government U.S. agency focused on health related standards for products and services, approval indicates product is suited for applications such as food handling; also: (Norges Standardiseringsforbund), standards group in Norway.
NSM—Network of Systems Management
NSP—Native Signal Processing; Intel® processor initiative for text-to-speech conversion.
NT—New Technology; used for Microsoft® computing platform.
NTC—Negative Temperature Coefficient, such as in NTC resistor (thermistor) which will make large, abrupt change in resistance when undercurrent or low temperature cools it below some specific point, thereby effectively "switching OFF," or in reality, acting like solid state fuse.
NTE—Windows Embedded NT computer operating systm from Microsoft®.
NTL—Non Threshold Logic.
NTP—Network Time Protocol; see definition.
NTSC—(National Television System Committee) sets video standards in United States; 525 lines, 60 Hz, 110 Volts, 30 frames per second in an interlaced analog signal; world's first compatible color television service, started in 1953; became the standard for much of North America; sometimes referred to as "Never Twice the Same Color" J; see also SECAM, PAL, PAL-M; NTSC standard is incompatible with most computer video standards, which generally use RGB video signals, special video adapters will convert NTSC signals into computer video signals and vice versa.
NTW—N(ext) T(echnology) Workstation; Microsoft® WindowsNT workstation operating system.
NuBus—Bus used in the Macintosh™ computer by Apple®.
NUI—Normally Unattended Installations (such as offshore).
Null Modem—Communication device which interfaces between some local peripheral that normally requires a modem, and computer near it that expects to drive a modem to interface to that device; an imitation modem in both directions.
Null—Condition, such as balance, which results in minimum absolute value of signal.
Numeric Control—Category of automated machine tools, such as drills & lathes, that operate from instructions in a program for use in automated in manufacturing tasks, such as milling, turning, punching and drilling; term ios from 1950s when instructions to tools were numeric codes, but like computer industry, symbolic languages were soon developed, nevertheless original term remained.
NURBS—Non Uniform Rational B-Splines; B-splines for ensuring continuity among objects;
NVLAP—(National Voluntary Laboratory Accreditation Program); part of the Standards Services Division within NIST's Technology Services; provides third-party accreditation to testing and calibration laboratories whose programs are established in response to Congressional mandates or administrative actions by the U.S. Federal Government or from requests by private-sector organizations; administered by NIST to accredit labs in field of computer communications software; use of these accredited labs is required by the U.S. GOSIP Testing program.
NVP—Nominal Velocity Propagation (of signals within cables).
NVRAM—Non-Volatile Random Access Memory; type of memory that retains its contents when power is turned off; one type is SRAM that is made non-volatile by connecting it to constant power source such as battery; another type uses EEPROM chips to save its contents when power is turned off, which is composed of a combination of SRAM and EEPROM chips
NVT—Network Virtual Terminal.
Nyquist Theorem—Law of sampling theory stating that data sampling frequency should be at least twice that of highest frequency variations in signal of interest; must be observed to preserve patterns in data and to not introduct artifical, lower frequency patterns.
Nyquist Rate—In digital signal processing (DSP), lowest sampling rate necessary to completely reconstruct signal without distortion due to aliasing; equal to twice highest frequency component of signal.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Intro
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