JAOMAD Glossary M:
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
M—(upper case)Abbreviation for Mega-, prefix in math for multiple of 106 (=1,000,000); also: in computing, multiple of 220 (=1,048,576) [Megabyte=220 bytes]; also: m(lower case) abbreviation for milli-, prefix in math for submultiple of 10-3 (=0.001); also: formerly meant "Moisture"(Humidity) when used in first alpha character position of ISA instrument function tag, still means "Momentary" as modifier, still means "Middle" or "Intermediate" when in succeeding letters [see ANSI/ISA S5.1-1984 (R1992)]; also: Mouse.
µ—Micro, in math (and often in computer terminology), is abbreviation for 10-6, (0.000001).
µC—Microcontroller; microprocessor with timers, counters, RAM, & ROM included; also: microcomputer, see definitions.
µP—Microprocessor; electronic integrated circuit, typically single-chip package, capable of receiving and executing coded instructions; performs functions of both CPU and ALU, but excludes memory and I/O systems.
M-Business—Mobile Business; m-Business is a subset of e-business; overall term for business based on mobile electronic media and wireless networks; beside traditional e-Business applications m-Business can provide additional value through e.g. location services; main electronic communication standard for m-Business is WAP.
M2M—Machine-to-Machine; communication network technologies between different plant floor equipment & controls, usually in context of Asset Management.
M-Commerce—Mobile Commerce; internet intersection of m-business and e-commerce; m-Commerce is the overall term for all sorts of transactions based on mobile electronic media and wireless networks.
MAC—Media Access Control; see definition; also: Maximum Allowable Concentration; also: Main Automation Contractor, see definition.
MACE—Macintosh Audio Compression/Expansion digital data compression standard developed by Apple and used in Macintosh method of saving digital audio in electronic memory, used for exchanging data between computers in Audio Interchange File Format (AIFF).
Machine Language—Instructions written in binary form that computer can execute directly; also called machine code, object code, and object language.
Machine Vision—Computer perception of visually based sensory output used to produce concise description of an image; devices used for optical non-contact sensing to receive and interpret automatically an image of actual scene in order to obtain information or to control some process.
MACINTOSH—Most Applications Crash; If Not, The Operating System HangsJ.
Macro—A kind of computer shorthand that reduces many programming commands to one, making it easy to activate functions that are used frequently.
MACT—Maximum Achievable Control Technology, usually in reference of response to EPA (U.S.) regulations.
MAF—Mass Air Flow.
Magenta—Color hue which transmits only blue and red light with no green from video screen view; reflects only red and blue light and absorbs green light on paper using 4-color process inks.
Magnetic Medium—Any data storage medium and related technology, such as core, drum, film, tape, and disk, in which different patterns of magnetization represent bit values.
Magnetic Tunneling Junction—Used in computer memory design similar to core memory, but made of sandwitched layers of thin magnetic material separated by layers of insulating material; passing current through wires above junction will cause polarity of junction to change, affecting change in resistance for electrons tunneling through sandwhich and creating 1 or 0 bit; will retain polarity even if power is removed; see MRAM, VRAM, RAM, DRAM, SRAM, Core Memory.
Magnetoresistive (MR)—Changes in electrical resistance in materials composed of metallic elements, or magnetic metals used in memory storage devices.
Magnetostriction—Magnetic field produces small change in physical dimension of ferromagnetic materials on the order of several parts per million in carbon steel and conversely, a physical deformation or stain (torsion) produces change of magnetization in the material.
Magnitude—In digital signal processing (DSP), square root of sum of the squares of real and imaginary parts of a complex signal.
Maillist—In e-mail systems, (usually automated) method allowing message to be sent to only one address, where it is then routed to specific other addresses.
Main Automation Contractor—Used on large projects; concept is to identify all automation activities, develop an execution plan, obtain the best resources, select the best technologies and then let the resources do what they do best.
Mainframe—Large-scale computer system that can house comprehensive software and several peripherals; "opposite" of distributed system; also: currently can mean chassis that mechanically contains boards or modules inserted into a backplane, providing environmental conditioning, vibration, and shock-resistant connections.
Mains—Main power source supplied by power company or central generator of self-sufficient site; British equivalent to what in U.S. is called Line Power.
Make-to Order—Products manufactured to specific customer order configuration and delivery time specifications.
Make-to-Stock—products manufactured to finished-goods storage before customer order arrives.
MAN—Metropolitan Area Network; "stretched" LAN providing digital data communications over distance of about 50 km, generally associated with IEEE 802.6 MAN standard.
Managed Hub— See Smart Hub, Hub.
Managed Security System Provider (MSSP)—Company that offers cyber security resources around the clock to monitor, evaluate, and quickly respond to information gathered from NIDS, HIDS, audit logs, and other sources in a network usually with correlation and analysis engines to process the massive amount of data received daily, such as reducing 5 million events a day to 200 or fewer events that require human evaluation.
Manchester Encoding—Digital encoding technique (specified for IEEE 802.3, Ethernet) in which each bit is divided into two complementary halves; negative-to-positive (voltage) transition in middle of the bit period designates binary "1," while positive-to-negative transition represents "0;" the technique also allows receiving device to recover the transmitted clock from incoming data stream (self clocking).
MANET—Mobile Ad hoc Networks; see definition.
Manipulated Variable (MV)—In process control, quality or condition altered by control action in order to change value of the regulated condition.
Manual Loading Station, Manual Station, Manual Loader—Device or function having manually adjustable output that is used to actuate one or more remote devices; station does not provide switching between manual and automatic modes of control loop (see Controller and Control Station); station may have integral indicators, lights, or other features.
Manual Reset—Adjustment on proportioning controller which shifts proportioning band in relationship to setpoint to eliminate droop or offset errors.
Manual Reset Switch—Switch in limit controller that manually resets controller after limit has been exceeded.
Manufacturing Execution System (MES)—Software packages to deliver information enabling optimization of production activities from order to goods by guiding, initiatiating, responding to, and reporting on plant activities; model concept developed by Advanced Manufacturing Research (AMR), Boston, MA, USA in late 1980s with intention to describe system which, rather than focusing on measurements of material usage or process control, “centers on product itself as it moves through plant on way to customer;” intended to bridge real-time information gap between planning (MIS) and controls (PCS) to link operators and managers with current views of all processing resources; counterpart of MOM model developed by GartnerGroup.
Manufacturing Message Specification (MMS)—ISO standard 9506, OSI application-layer protocol for messaging within and between industrial automation systems.
Manufacturing Operations Management (System), MOM(S)—Software packages for such functions as plant management, supervisory control and monitoring, plant engineering, and quality management; model concept developed by GartnerGroup Stamford, CT, USA, intended to bridge real-time information gap between planning (MIS) and controls (PCS) to link operators and managers with current views of all processing resources; counterpart of MES model developed by Advanced Manufacturing Research (AMR).
MAP—Manufacturing Automation Protocol; based on IEEE 802.4; General Motors® originated networking protocol which follows seven layer OSI model [Note: MAP-Compliant means it conforms to specifications AND will talk with other devices over the system; MAP-Compatible means only that it will not interfere (physical & datalink layers only) with "foreign" devices, but only talk with like devices while sharing the timing with those foreign devices]; also: Manifold Absolute Pressure engine sensor.
MAP/EPA—MAP Extended Performance Architecture; dual architecture which supports both full MAP seven layer communication architecture as well as architecture for time critical communication which bypasses layers 3, 4, 5, & 6.
MAPI—Messaging Application Programming Interface; messaging API by Microsoft®; in distributed client/server digital communication environments, MAPI treats client and server components as independent applications; see API, and definition.
MAPI-WF— Messaging Application Programming Interface-Workflow Framework; proprietary messaging Application Programming Interface (API) by Microsoft® as effort to create De Facto standard for workflow engine interoperability on Internet.
Mapping—In digital communication network operations, logical association of one set of values, such as addresses on one network, with quantities or values of another set, such as devices on another network (that is, name-address inter-network route, protocol-to-protocol mapping).
Margins—In typographical composition of video screen displays and printing, white space surrounding text area on a page.
Mark—Presence of some signal; in current communication, such as telegraph, this represents closed condition or current flowing equivalent to binary 1.
Marshaling Cabinet—Cabinet, sometimes located outside control or rack rooms, which houses terminal boards for plant or process field wiring, in which the wiring coming from or going to divergent locations, is re-arranged appropriately to control system I/O requirements, often with signal conditioning equipment, such as needed for various transmitters and sensors; terminology comes from railroad marshaling yards (called switch yards in US).
Mass Flow—Actual content of material in flow, correcting for pressure and temperature changes; volumetric flowrate times density, such as pounds per hour, or kilograms per minute.
Mass Storage—Digital device like disk or magnetic tape that can store large amounts of data readily accessible to central processing unit.
Master Station—See Primary Station.
Material Dispersion—Dispersion resulting from the different velocities of each wavelength in an optical fiber.
Material Requirements Planning (MRP)—(and MRP II or development phase II called Manufacturing Resource Planning); computerized method for planning plant's use of resources, including raw materials, financial, vendors, production equipment, and processes; Push Manufacturing style operations where production is based upon forecast demand; compare: Flow or Pull Manufacturing.
Matrix Control Strategies (MCS)—in process control, strategies which regulate process from several inputs, usually involving unit severities and product compositions; likewise called Multivariable Predictive Control Strategies.
MATS—Material Transport Segment.
MAU—Multistation Access Unit; wiring concentrator used in local area networks; also: Media Attachment Unit, also known as transceiver and not to be confused with Token Ring MAU (Media Access Unit), Ethernet device for transmitting and receiving data that often provides data packet collision detection as well; can either be internal or external feature of network device such as network interface card, repeater, hub, or concentrator; multiport MAU, or transceiver, allows number of computers or workstations to be attached to single connection on Ethernet bus and each port performs standard transceiver functions.
Maximum Elongation—In strain gauges for force or pressure measurements, strain value where deviation of more than ±5% occurs with respect to mean characteristic (resistance change vs. strain).
Maximum Excitation—Maximum value of excitation voltage or current that can be applied to some device at ambient conditions without causing damage or performance degradation beyond specified tolerances.
Maximum Operating Conditions—Maximum environmental conditions in which device or system can operate safely, but may limit life span of that device or system compared to operating in specified normal conditions.
MB—MegaByte, see definition.
Mb—Megabit; 1,048,576 bits.
MBE—ModBus over Ethernet.
MBone—Multicasting Backbone; subset of Internet capable of Multicasting; not a separate backbone, but is address space laid on existing backbones that operate the Internet and Intranets; started as "a wild idea" in 1992 when Allison Mankin, researcher involved with Internet Engineering Task Force (IETF), was too far along in her pregnancy to travel to San Diego for needed meeting, and suggested extending experimental multicasting technology so she and others who could not attend, could still fully participate; see Multicasting.
MBPC—Model Based Predictive Control; see definition.
Mbps, Mb/s—Million Bits Per Second.
MC—Multivariable Control; process control of many variables, generally based upon many inputs; usually the term implies need for some advanced control strategy.
MCA—Micro Channel Architecture; bus design of some PS/2 models.
MCAA—(Measurement and Control Automation Association); source of some automation standards; a trade association of leading companies who manufacture and distribute a wide variety of process controls, field measurement and analysis instrumentation, systems and software used in industrial process control and factory automation around the world; formerly a part of Scientific Apparatus Makers Association (SAMA) but originally founded in the 1940s as Recorder-Controller, Inc
MCAD—Mechanical Computer Aided Design.
MCAE—Mechanical Computer-Aided Engineering.
MCC—Model Correction Coefficient; method of measuring process control loop tuning effectiveness; also: Motor Control Center.
MCGA—Multi-Color Graphics Array (or Adapter); created specifically for PS/2® models 25 & 30; does not work with EGA software.
MCI—Media Control Interface.
MCL—Maximum Contaminant Level.
MCR—Maximum Continuous Rating.
MCS—Matrix Control Strategies; in process control, strategies which regulate process from several inputs, usually involving unit severities and product compositions; likewise called Multivariable Predictive Control Strategies.
MCT—Multi-Cable Transit; see definition.
MCU—MicroController Unit, see Microcontroller.
MD—MiniDisc; optical memory media which uses digital audio compression method (ATRAC) for quality similar to CD, but with less "data."
MDA—Monochrome Display Adapter; video standard introduced by IBM® in 1982 for IBM®PC, PC/XT™ & AT™ computers and compatibles which handled only textual data and eventually replaced by a card; also: Methylenedianiline.
MDI—Multiple Document Interface; also: Medium-Dependent Interface, in data communications, mechanical and electrical interface between network segment and Media Attachment Unit (MAU).
MDR—Magnetic Disk Recorder.
MDRAM—Multibank Dynamic Random Access Memory;; relatively new memory technology developed by MoSys Inc. which uses small banks of DRAM (32 KB each) in an array, where each bank has its own I/O port that feeds into a common internal bus, thus data can be read or written to multiple banks simultaneously, which makes it much faster than conventional DRAM; because memory can be configured in smaller increments, this can reduce cost of some components.
MDS—Microprocessor Development System.
MDSI—Multiple Double Short Time Integration; semiconductor technology that directs low-power laser pulses on object to be measured, resulting reflected light is detected by CMOS image converter with very short integration times; large number of laser pulses are then added up on image converter chip where analysis of light run/travel time, using single CMOS chip, simultaneously measures distance to 1,000 different object points with resolution of about 1 cm. in only one thousandth of second to detect entire 3D image.
Mean—Average of maximum and minimum values at (process) equilibrium.
Measurand—Physical quantity, property, or condition which is measured.
Measure—In typographical composition of screen displays and printing, the width of type, usually expressed in picas.
Measured Variable (MV)—in process control, that variable of process which is monitored by sensor to provide signal to controller, sometimes called Process Variable (PV).
Measurement—Determination of existence or magnitude of a variable.
Measuring Junction—That thermocouple junction referred to as the hot junction which is used to measure as unknown temperature.
Mechanic's Knife—Used to open and slice through the contents of cardboard cartons delivered to your front door; works particularly well on contents such as seats, vinyl records, liquids in plastic bottles, collector magazines, refund checks, and rubber or plastic parts; especially useful for slicing work clothes, but only while in use. J
Mechanical Event Simulation (MES)—Combines kinematic, rigid, and flexible-body dynamics, and nonlinear stress analysis.
Media Access Control (MAC)—Networking layer that determines which node can access physical media; media specific access-control protocol within IEEE 802 specifications (lower sublayer of layer 2 of ISO model) which includes variations for token ring, token bus, and CSMA/CD; checksum that is computed using algorithm based on DES or AES ciphers, which use secret key rather than private key, gets sent with message which is compared at receiver to confirm integrity.
Media Attachment Unit (MAU)—Also known as transceiver and not to be confused with Token Ring MAU (Media Access Unit), Ethernet device for transmitting and receiving data that often provides data packet collision detection as well; can either be internal or external feature of network device such as network interface card, repeater, hub, or concentrator; multiport MAU, or transceiver, allows number of computers or workstations to be attached to single connection on Ethernet bus and each port performs standard transceiver functions.
Media Management—Ability to manage (process of managing) different media used in same network, such as coaxial cable, twisted pair cable, and fiber optic cable; involves cable performance monitoring, cable break detection, planning for cable routes, etc.
Material Requirements Planning (MRP)—(and MRP II or development phase II called Manufacturing Resource Planning); computerized method for planning plant's use of resources, including raw materials, financial, vendors, production equipment, and processes; Push Manufacturing style operations where production is based upon forecast demand; compare: Flow or Pull Manufacturing.
Median—Middle value in sample of rank-ordered data or measurements; there are as many values in this sample larger in a median as there are smaller.
Medium—Any material substance used for propagation or transmission of signals, usually in form of electrons, light, modulated radio, or acoustic waves; such as optical fiber, metal wire, dielectric slab, air, water, free space, etc.
Medium-Dependant Interface (MDI)—In data communications, mechanical and electrical interface between network segment and Media Attachment Unit (MAU).
Megabyte—Mbyte, Meg, MB; 1,048,576 bytes; 1024 kilobytes (220 bytes); basic unit of measurement of mass storage; also: used in describing data transfer rates (primarily parallel) as function of time (Mbps).
Megacycle—103 Bicycles. J
MegaFLOPS—One Million Floating Point Operations Per Second; expression of computing power of processor.
Megahertz (MHz)—Unit of measurement equaling one million cycles per second.
MELF—Metal Electrode Face; discrete leadless component.
Memory—In computing, device into which data can be entered, in which it can be held, and from which it can be later retrieved; usually considered kept electronically, as on chips (in RAM or ROM), rather than magnetically or optically on disks (stored media, usually referred to as storage); also: of all computer components, it is the most generous in terms of variety, and skimpiest in terms of quantity. J
Memory Card (Flash Card)—Electronic flash memory data storage device used for storing digital information, commonly used in many electronic devices; they are small, re-recordable, and able to retain data without power; a popular physical medium for transferring files, and have become increasingly smaller in size as technology advances; see also FlashMemory.
Memory Mapping—Duplication of all or part of data in one memory location to memory in another location or device.
Memory Stick—Flash memory card from Sony designed for digital storage on cameras, camcorders and other handheld devices. Introduced in 1998 with 4 and 8MB capacities, storage has increased to 1GB with the Memory Stick PRO format; see USB Flash Drive.
Memristor —Passive circuit element that relates flux to charge in the same way that resistors relate voltage to current, capacitors relate voltage to charge, and inductors relate flux to current; invented in 1971, but practical fabrication is just becoming possible in 2008; one application is to use it in resistive RAMs to create ultra-dense memory cells.
MEMS—Micro-Electro-Mechanical Systems; see definition.
Menu—Method on workstation screens to select alternative functions displayed as a list and chosen through mouse, key, sequence of keys, touchscreen hotspots, etc. rather than command language of computer program.
MES—Manufacturing Execution System; see definition; also: Mechanical Event Simulation, see definition.
MESA—(Manufacturing Execution System Association); Pittsburgh, PA, USA based not-for-profit consortium of 25 suppliers of MES software, services, and related technologies; has goal to educate potential users about benefits of MES and to act as resource for media and public.
MESFET—Metalized Semiconductor Field Effect Transistor; FET where Schottky barrier is used for gate.
Message—In object oriented software, interaction of objects, through which an object may call a method in another object; see Method.
Message Box—In workstation screen views, special dialog box within application window which displays information needed at some appropriate point of activity within that application; may alert the user when information is needed, or to display diagnostics when some error has occurred.
Message Switching—Method of handling messages over communications networks where entire message is transmitted to intermediate point (such as switching computer), stored for period of time (may be very short period), then transmitted towards its destination (each destination indicated by an address integral to the message); see also Circuit Switching and Packet Switching.
Messaging—In Object Oriented Programming (OOP), objects communicating according to defined rules.
Messaging Application Programming Interface— System built into Microsoft Windows enabling different e-mail applications to work together for mail distribution; as long as both applications are MAPI-enabled, they can share mail messages with each other; MAPI confusion occurs because of two very different kinds: First, MAPI of Microsoft Mail (MS-Mail) which was C-language API allowing programmable access to those features, now called "Simple MAPI"; "new MAPI" is COM/OLE-based set of complex interfaces, sometimes called "Extended MAPI" or XMAPI, which includes Simple MAPI for compatibility with older software and includes OLE Messaging, which is set of OLE Automation interfaces to messaging, for use in Visual Basic, etc.
Metadata—Data about data; may describe an individual datum, or content item, or a collection of data including multiple content items and used to facilitate the understanding, use and management of data; varies with the type of data and context of use, such as a library where data is content of the titles stocked, metadata about a title would typically include a description of the content, the author, the publication date and the physical location.
Metcalfe's Law—Suggested by Robert Metcalfe, originator of Ethernet and founder of 3COM which says that value of network is proportional to square of number of nodes; so, as network grows, value of being connected to it grows exponentially, while cost per user remains same or even reduces; see also Gilder’s Law & Moore’s Law.
Methods—In object oriented software, set of software procedures used to produce some desired output; can include a calculation, or signal manipulating some device; similar to Function.
MFAC—Model Free Adaptive Controller; see definition.
MFC—Microsoft® Foundation Class; common computer software function libraries; also: MultiFunction Controller; term used by several process control systems vendors for controller which contains software algorithms for loop, logic, and sequential process control within the same module.
MFD—Mode Field Diameter; diameter of optical energy in single mode optical fiber; because it is greater than core diameter, MFD replaces core diameter as practical parameter.
MFLOPS—Million Floating Point Operations Per Second [megaflops]; expression of computing power of processor.
MFP—MultiFunction Printer; printer which will also scan, fax, and copy.
MFT—Main Fuel Trip; terminology which originated with power generation industry.
MGA—Monochrome Graphics Adapter; also: Murky Gray Area; reference by wags to the lack of definitive line of responsibility between Business Planning Software and Process Control Software when these two operations are actually connected; serious concern of ISA SP95 effort to define Enterprise/Process functions.K
MHCS—Material Handling Control System software.
MHD—Moving Head Disk.
MHL—Microprocessor Host Loader.
Mho—In Conductivity measurement, unit of conductance of solution, now called Siemens (S); and is reciprocal of its resistance in Ohms.
MHS- Message Handling System standard defined by ISO and CCITT; also: Message Handling Service defined as something of a standard by Action Technologies Inc., licensed and distributed by Novell®.
MHSB—Monitored Hot StandBy.
MHz—MegaHertz;unit of measurement equaling one million cycles per second.
MICC—Main Instrument & Controls Contractor; subset of the role of Engineering, Procuring, and Construction company which designs and builds process plant, usually done by the controls supplier.
Microcomputer, µC—Based on microprocessor, computer which is physically small, usually fits on small printed circuit board and works with data word of 4, 8, or 16 bits, but now often with all the power formerly found in minicomputers; also called personal computer.
Microcontroller, µC—Microprocessor with timers, counters, RAM, & ROM included; see COC.
Micro-Electro-Mechanical Systems (MEMS)—Micromachined integrated systems, usually on silicon chips and measured in micrometers; perform some intelligent sensing function along with micro-moving sensing diaphragms and beams, actuating devices such as valves, motors, linear motors, cantilevers, switches and gear trains; used to make pressure, temperature, chemical and vibration sensors, light reflectors and switches as well as accelerometers for airbags, vehicle control, pacemakers, games, ink jet print heads, microactuators for read/write heads and all-optical switches that reflect light beams to appropriate output ports.
Microfiche—[pronounced: micro-feesh]; 4x6" sheet of film that holds several hundred miniaturized document pages, see micrographics; also: 10-6 fish. J
Micrographics—Production, handling and use of microfilm and microfiche where images are created by cameras or by COM units that accept computer output directly; documents are magnified for human viewing by readers, some of which can automatically locate page using indexing techniques; continual economical alternative for high-volume data and picture storage; although optical disks have superseded fiche and film for most archival storage, film is still the only medium that can survive continual upgrading of electronic technologies (which generally remain compatible with only one or two generations of media).
Micromachine – Same as MicroElectroMechanical Systems; see definition.Micron—One millionth of a meter (10-6).
Micron Rating—Arbitrary value assigned to filters or media; although "micron" is a length, "micron rating" is not actually a measured value; micron rating for a filter quotes particle size without establishing filter's efficiency at removing that size of particles.
Microprocessor, µP—Electronic integrated circuit, typically single-chip package, capable of receiving and executing coded instructions; performs functions of both CPU and ALU, but excludes memory and I/O systems.
Middleware—Loosely defined as software to interconnect application software from separate vendors which are for different plant functions; also: in object oriented software, procedure followed when an object request requires information from another object, such as when object A calls a method in object B, where object B must first obtain an interim data value form object C (object B is the middleware).
MIDI—Musical Instrument Digital Interface; industry standard connection for computer control of musical instruments and devices; also: what Mickey Mouse calls his girlfriend when he has a cold.J
MIF—Minimum Networking Functionality; general principle within OSI that calls for minimum LAN station complexity when interconnecting with resources outside the LAN.
Milestones—Identified events to indicate progression of project.
MIL-STD—(USA) Military Standard.
MIMD—[pronounced: mimdee] Multiple Instruction Multiple Data computing where at every instant each processor applies its own unique set of instructions on the data in its own local memory; see SIMD.
MIME—Multipurpose Internet Mail Extensions; Internet digital communication standard protocol which allows message to contain textual, binary or arbitrarily formatted data, such as sounds, cinema, and images.
MIMO—Multiple Input Multiple Output; systems requiring complex control methods; see SISO, MISO, TITO.
MIMOSA—(Machinery Information Management Open Systems Alliance); not-for-profit trade association dedicated to developing and encouraging the adoption of open information standards for Operations and Maintenance in manufacturing, fleet, and facility environments; provide open standards enable collaborative asset lifecycle management in both commercial and military applications.
Mini-MAP—Mini-Manufacturing Automation Protocol; version of MAP consisting of only physical, link, and application layers, intended for lower process control networks; using Mini-MAP, device with token can request response from an address device, and unlike standard MAP protocol, addressed device need not wait for token to respond.
Minicomputer—Class of computer that has its CPU constructed of number of discrete components and integrated circuits, rather than being comprised of single integrated circuit, as in microprocessor; mini is larger than microcomputer, and has typical word length of 16 or 32 bits; it is small, programmable, general purpose computer typically used for dedicated applications.
Minus Leading—In typographical composition of screen displays and printing, leading in which baseline space is less than point size (or less than solid leading).
MIP—Middleware Integration Platform; provides capability to connect multiple control systems to multiple manufacturing &/or business applications; integration functionality includes event handling, messaging, workflow transactions, systems management, dynamic configuration, some form of database management, etc.
MIPS—Million Instructions Per Second; unit for expressing speed of processor execution of machine code instructions (rough measure of processing power).
MIR—Micropower Impulse Radar; inexpensive, small, sensor useful for motion detectors as well as flow and level sensors; works by its rapid-fire sampler, which enables it to analyze radio pulses that are extremely shorter than conventional radar, giving it tremendous accuracy at low power; also: Maturity Index of Reliability; system developed at Eindhoven University in the Netherlands, used to meet requirements of IEC61508 for organization safety; also: Moisture Insulation Resistance.
Mirroring—In workstation screen displays, display or creation of some graphic that portrays image in exact reverse orientation it originally had by flipping that graphic on its x-axis or y-axis.
MIS—Management Information System; computer network which allows managers to track performance of plant at close to real-time without excessive need for paper based systems; primarily used for planning and scheduling of resources; also: Metal Insulator Silicon.
Misalignment Loss—In fiber optics, loss of power resulting from angular misalignment, lateral displacement, and end separation.
MISFET, MIST—Metal Insulated Silicon Field effect Transistor; alternative name for MESFET.
MISO—Multiple Input Single Output; systems requiring advanced control methods, such as fuzzy logic & neural networks; see SISO, MIMO, TITO.
MITI—(Ministry of International Trade and Industry) of Japan.
MKS—Meter-Kilogram-Second; system of absolute units for length, mass, time; now the basis of SI units.
MLA—Microprocessor Language Assembler.
MLCC—MultiLayer Chip Capacitor.
MLE—Microprocessor Language Editor.
MMC—Maximum Material Condition.
MMCD—MultiMedia Compact Disk made by Sony®/Phillips®; now called DVD; see DVD.
MMFS—[pronounced: Memphis] Manufacturing Message Format Standard; MAP layer 7 for numeric control, PLCs, robot control; replaced by MMS.
MMG—(Multibus Manufacturers Group)
MMI—Man Machine Interface; increasing (preferred) use of term HMI (human machine interface) is being seen; also: Manufacturing Management Information; a term promoted by Wonderware for their more expanded vision of the operator’s function.
MMIC—Monolithic Microwave Integrated Circuits.
MMS—Manufacturing Message Specification (part of MAP 3,0 Layer 7); ISO standard 9506, OSI application-layer protocol for messaging within and between industrial automation systems; also: Maintenance Management System.
MMU—Memory Management Unit.
MMXTM—MultiMedia eXtension; performance boosting technology incorporated 57 multimedia-centric instructions into Pentium processors by Intel®, to achieve 10-20% improvement on standard CPU benchmarks, and up to 60% performance when running software specifically designed for technology of audio, video and graphics; involves processing trick known as “single instruction, multiple data,” enabling MMX chip to package and process many pieces of information as one value, rather than one-at-a-time sequence that could cause bottlenecks.
MNCS—Multipoint Network Control System.
Mnemonic—technique used to aid human memory such as word or code (letters, symbols, etc.) for programming that are easy to remember, or suggest correct response.
MNOS—Metal Nitride Oxide Semiconductor.
MNPT—Male National Pipe Thread.
MO—Model Output; signal in the Model Correction Coefficient method of measuring process control loop tuning effectiveness; also: Magneto-Optical, technology which uses laser to heat magnetic spot to 200°C within magnetic field to change data; allows millions of rewrites.
Mobile Ad hoc Networks (MANET)—Can provide efficient mobile network architecture using the ability to distinguish trusted peers, and tolerate the ingress/egress of nodes on an unscheduled basis with a molecular biology model such as DNA evolution which can provide a basis for a proprietary security architecture that achieves high degrees of diffusion and confusion, and resistance to cryptanalysis.
MOC—Management Of Change.
MOCVD—Metal-Organic Chemical Vapor Deposition.
Modal—Mode oriented; a modal operation switches from one mode to another; Contrast with Non-modal.
Modal Bandwidth—Capacity of optical fiber measured in MHz-km (megahertz over one kilometer); One MHz-km equals approximately 0.7 to 0.8 Mbps, so 100 MHz-km fiber can carry about 70 to 80 Mbps of data.
Modal Dispersion—Dispersion resulting from different transit lengths of different propagating modes in multimode optical fiber.
Modal Window—In computer programming, a pop-up window within a program which causes that program to pause or stop while it is opened; compare with Non-modal Window.
Modbus RTU—Popular Modicon® master/slave protocol, owned by AEG Schneider Automation; used by PLCs and specialty instrumentation such as analyzers, chromatographs, weigh scales, operator interfaces, RTUs as well as DCSs.
Modbus Plus—Popular Modicon® master/slave protocol, owned by AEG Schneider Automation; inherently multidrop, has communication rate of 1 Mbps.
Mode—Method or condition of operation; also: in fiber optics (& guided wave propagation), distribution of electromagnetic energy that satisfies Maxwell’s equation and boundary conditions; loosely, a possible path followed by light rays; also: in SPC, most frequently occurring value in a sample; also: in controls, output form or type of action, see Control Mode.
Modeling—Recreation of event or object in controlled environment to predict results from that event or object.
Model Based Predictive Control—In process control, similar to our own learning experience, method of process control for use beyond abilities of traditional PID type; uses correlation of training [or operating image (internal model)], target [or reference trajectory], action [computation of structured manipulated variable], and comparison of actual vs. expected [modeling error compensator]; MBPC eliminates many of manual tasks involved with readjusting process as required by comparing desired process results (model) with actual process data and readjusts process settings to maintain the process within specified limits; using data history, MBPC is able to adjust process settings accordingly to minimize variability in the overall process.
Model Free Adaptive Controller (MFAC)—In process control, controller that provides small interactive control strategies in lieu of a specific feedforward design, and adapts to changes in operating conditions; a 2x2 or 3x3 matrix is typical; compare with Model Reference Adaptive Control.
Model Predictive Control—See Model Based Predictive Control.
Model Reference Adaptive Control—Method of self-adaptive control comparing real process parameters with reference model; compare with Model Free Adaptive Control.
Modeling—Mathematically characterizing process so that variables may be manipulated to determine their behavior in different situations.
MODEM—MODulator/DEModulator; interface device for data processing equipment to convert data to form acceptable for sending and receiving on transmission facilities, most commonly telephone lines.
MODICON—MOdular DIgital CONtroller; claimed as first PLC, designed on New Year’s Day, 1968 (see Cyclelog); model 084 developed by Dick Morely, though he gives credit to Michael Greenberg for design of the 184, which really took off commercially with help of Lee Rousseau; name was used in forming the Modicon Company, later bought by Schneider.
MODULA-2—MODUlar LAnguage-2; computer language designed by Niklaus Wirth to enhance Pascal; multiprocessing language with co-routines that may be executed simultaneously.
Modulating Control—To vary output signal based upon some variation of input (vs. ON/OFF control).
Modulation—Process by which characteristic of one wave (the carrier) is modified by another wave (the signal), such as AM, FM, and PCM.
Module—Separate and distinct unit of hardware and/or software; usually card or subassembly of larger device, or component of larger system; software segment (such as function block, subroutines) within larger software program (or operation).
Modulo—Mathematical function that yields remainder of division; number x evaluated modulo n gives integer remainder of x/n, for example 200 modulo 47 equals remainder of 200/47, or 12.
MOEMS—Micro-Opto-Electro-Mechanical System; When optical components are included in a MEMS device; see Micro-Electro-Mechanical Systems.
MOLAP—Multi-dimensional On-Line Analytical Processing, see OLAP.
MOM(S)—Manufacturing Operations Management (System); see definition.
Monitor—As noun, general term for instrument or instrument system used to measure or sense status or magnitude of one or more variables for purpose of deriving useful information; term is very unspecific, sometimes meaning analyzer, indicator, alarm, or CRT.
Monitor Light—See Pilot Light.
Moore's Law—Suggested by Gordon Moore of Intel in early 1970's which says that processing power of a microchip doubles every 18 months; corollary, computers become faster and price of given level of computing power halves every 18 months; ("Law" is a misnomer; it's a "conjecture") all "technology modes" tend to follow an S-curve of growth (usually exponential) up to a "utility plateau" at which point they get replaced by the next technology; see also Gilder’s Law & Metcalf’s Law.
MOS—Metal Oxide Semiconductor; uses silicon dioxide layer as insulator and are special case of MIS transistors.
Mosaic—In computer networks, user interface software for navigating, browsing, and accessing files across network (now used with Internet); developed at National Center for Supercomputing Applications (NCSA) at University of Illinois.
MOSFET, MOST—Metal Oxide Semiconductor Field Effect Transistor; alternative name for MESFET.
Motherboard—Printed circuit board of computer that contains bus lines and edge connectors to accommodate other boards in the system; in microcomputer, motherboard often contains microprocessor and expansion boards.
Motif—Graphical user interface defined by OSF based largely upon DEC® and others.
Motion Control—Application of moving parts in industrial settings including sequencing, speed control, point-to-point control, and incremental motion; control options include timers and counters, chip level and board level computers, programmable logic controllers, and pneumatic sequencers; combination of motors to control robotic action in unison for specific combined motion.
Motion JPEG—In video development, any of several proprietary implementations of motion video compression based on JPEG standard which produces outstanding quality video when degree or amount of compression is not overdone.
MOTIS—Message Oriented Text Interchange System; ISO 10021.
MOU—Memoranda Of Understanding.
Mouse—Hand-held device developed by Doug Englebart in 1964 that is moved along flat surface to drive and place cursor on workstation screen to direct views or operator inputs; also: any of various small rodents with pointed snout, slender body, pointed tail, and made to seem harmless by numerous cartoonists. J
MOV—Metal Oxide Varistor; device whose impedance changes appreciably in response to applied voltage; used to limit maximum voltage across output device and protect vulnerable circuit components against transients by clamping circuit to safe levels; also: Motor Operated Valves.
µP—MicroProcessor; see definition.
MPC—Model Predictive Control; see Model Based Predictive Control; also called Multivariable Predictive Control, in process control, strategies which regulate process from several inputs, usually involving unit severities and product compositions; likewise called Matrix Control Strategies; also: Multimedia Personal Computer, which uses wave-table (FM) synthesis to generate complex frequencies, such as found in music; also: (Multimedia PC Council) standards group.
MPCS—Manufacturing Planning & Control System; also: Manufacturing Planning & Control Software).
MPEG—(Motion Picture Experts Group); standards committee under auspices of ISO working on algorithm standards that will allow digital compression, storage, and transmission of moving image information such as motion video; CD quality audio and control data at CD-ROM bandwidth; MPEG algorithm provides interframe compression of video images and can have an effective compression rate of 100:1 to 200:1.
MPEG 2—Proposed standard for ISO adaptation that allows for higher resolution motion video compression than MPEG standard.
MPI—Metallized Particle Interconnect; component connection technology which consists of proprietary polymer material embedded with metallized particles and formed into tiny micro-columns 0.025” diameter, 1 mm high; when mechanically compressed by frame holding microprocessor, metallized particles within compressed columns are joined to form conductive path between contacts.
MPII—MAP in Process Industries Initiative.
MPLS—MultiProtocol Label Switching; see definition; once called MultiProtocol Lambda Switching.
MPP—Massively Parallel Processing; type of computer architecture using matrix of separate CPUs, each of which controls its own block of main memory and linked some way to communicate very quickly with each other.
MPR—Maximum Power Rating; maximum power in Watts at which device can safely operate.
MPS—Meters Per Second; also: Master Production Schedule.
MPU—MicroProcessor Unit, see Microprocessor.
MR—MagnetoResistive; see definition.
MRA—Mutual Recognition Agreement.
MRAC—Model Reference Adaptive Control; see definition.
MRAM—Magnetic Random Access Memory; MagnetoResistive Access Memory; combines non-volatility of flash memory with speed of SRAM and high density of DRAM which allow “instant-on” and replae hard drive;several design approaches used including use of magnetic tunneling junction and VRAM; see RAM, DRAM, SRAM, VRAM, Core Memory, MagneticTunneling Junction.
MRB—Management Request Broker; associated with Distributed Computing Environment by OSF.
MRO—Maintenance, Repair, and Operations.
MRP— Media Redundancy Protocol; see definition.; also: Material Requirements Planning (and MRP II or development phase II called Manufacturing Resource Planning); see definition.
M/S—Meters Per Second (MPS).
MS—Manual Station; provides process control signal directly to final element; also: (lower case) millisecond; also: used by some to mean Microsoft®.
MS-DOS®—Microsoft Disk Operating System; developed for IBM® PC and has become a de facto standard; sometimes called PC-DOS designed to control and manage I/O devices and memory for personal computers (PCs); see PC-DOS.
MS/TP—Master-Slave/Token-Passing; data link protocol of BACnet which provides same services to network layer that ISO 8802-2 (IEEE 802.2) LLC does.
MSB—Most Significant Bit.
MSD—Most Significant Digit; digit representing greatest value; also: MusculoSkeletal Disorders; OSHA defines MSD as injury or disorder of muscles, tendons, joints, spinal discs, nerves, ligaments, or cartilage; OSHA does not define MSDs to include slips, trips, and falls, being struck by objects or other similar accidents; OSHA cites carpal tunnel syndrome, herniated spinal discs, tendinitis, trigger finger, and lower back pain as examples of MSDs.
MSDS—Material Safety Data Sheets; carry information about what to do in emergencies when handling various specific, usually hazardous, materials.
MSHA—(Mine Safety and Health Administration); U.S. agency.
MSI—Medium Scale Integration; multifunction semiconductor, such as microprocessor, with between 12 and 1000 equivalent gates.
MSN—Manhattan Street Network; refers to mesh architecture using wavelength division multiplexing in digital communication.
MSPC—Multivariable Stasticial Parocsss Control; term used in context of automation strategies at plant level.
MSPS—Mega Samples Per Second
MSSP—Managed Security System Provider; see definition.
MSZH—Hungarian Office for Standardization.
MTA—Message Transfer Agent.
MTBA—Mean Time Between Assist.
MTBF—Mean Time Between Failures (since 1962) and calculated to be MTTF+MTTR; Mean Time Before Failure (prior to 1962 MIL spec. definition); stated or published period of time for which user may expect device or system to operate before failure occurs (a computed arithmetic mean of the time, not a tested value).
MTC—MIDDI Time Code.
MTD—Mass Tape Duplicator/verifier; also: in PCMCIA technology, Media Technology Drivers, which provide effective method for making upper software layers independent of card technology; intention that every PCMCIA have associated MTD to contain programming algorithms for various devices on that card.
MTF—Modulation Transfer Function; video focus test to measure contrast of adjacent single-pixel-wide black and white lines.
MTO—Make to Order.
MTS—Message Transfer Service.
MTTA—Mean Time To Assist
MTTF—Mean Time To Failure; used since 1962 as calculated measure of overall reliability (a computed arithmetic mean of the time, not a tested value).
MTTFD—Mean Time To Failure (to) Dangerous condition.
MTTFS—Mean Time To Failure (to) Safe condition.
MTTR—Mean Time To Repair; average time required to perform corrective maintenance on failed device or system.
MTU—Master Termination Unit; typically located in control room, these devices are designed to gather and disperse signals to Remote Termination Units (RTUs) which operate over some (often extreme) distance from the actual processing of control and operations; usually associated with SCADA systems for power transmission & distribution, water, oil & gas pipelines where RTUs must be capable of operating unattended for periods of time with no communication with balance of system.
Muffle—Insulated enclosure of a furnace.
MUG—(Manufacturing Users Group); sponsored by ARC Advisory Group market research firm; charter of MUG is to assist end users in development of strategies for optimum use of automation, supply chain, and e-business technologies for plant management; MUG membership is restricted to end-users only.
Multi-cable Transits (MCT)—Used for building/deck penetrations for multiple cables; consist primarily of a frame (typically rectangular) and insert blocks that fill the space within the frame and provide the cable penetrations through sides of vessels, walls, etc.
Multicasting—In networking, a distinctions are made among unicasting, broadcasting, and multicasting: Unicast sends message strings to many stations one at a time, cosuming significant bandwidth (like web & FTP servers); Broadcasting sends an unacknowledged message to everyone on the network simultaneously (one to many), whereas Multicasting sends an unacknowledged message simultaneously (one to many) to specific list of recipients (selected for need to know the content); this can be entirely interactive, carrying audio, video, and "white board" feature which enables participants to share text, images, and sketches; see Mbone; the 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; in a Distributed Control System, multicast capabilities permit multiple controllers to share input data and peer-to-peer interlocking data for greater performance and reduced programming requirements; see Unicast.
Multidimensional Database Management System—Database management system (DBMS) organized around groups of records that share a common field value; often generated from relational databases; whereas relational databases make it easy to work with individual records, multidimensional databases are designed for analyzing large groups of records; the term OLAP (On-Line Analytical Processing) has become almost synonymous with multidimensional databases, whereas OLTP (On-Line Transaction Processing) generally refers to relational DBMSs; compare: Flat File Database; Relational Database.
Multidrop—In fieldbus, connection of multiple field devices to one pair of wires, usually "tee-connected."
Multi-Functional Controller Platforms—Used to connect production floor operations with business systems; has multi-domain functionality, including logic, motion, HMI, and process control on a single platform; will allow users & OEMs to deploy multiple control applications on a single platform; has common development platform for the design and integration of multi-domain automated systems; will facilitate open, modular control architectures that enable highly distributed automated factory environments; employ de-facto standards for network interfaces, languages, etc., allowing data exchange as part of networked multi-vendor systems; called by some Enterprise Control Systems (ECS).
Multimedia—Describes any application that uses multiple media (graphics, text, animations, audio, video); in computer systems, primarily thought of as any application that uses high-bandwidth media (audio and video) and is most often delivered on CD-ROM; does not describe the purpose of the application, such as game, presentation, or computer-based training, nor does describe delivery media, such as CD-ROM, only the nature of media used in the application; computer and web-based training may also be considered multimedia applications if they incorporate multiple media to meet instructional objectives.
Multimode—Essentially, optical fiber designed to carry multiple signals, distinguished by frequency or phase, at the same time.
Multiplex—To interleave or simultaneously transmit two or more messages on single channel.
Multiplexor—Device used for division of transmission facility into two or more subchannels, either by splitting frequency into narrow bands (frequency division), or by allotting common channel to several different transmitting devices, one at a time (time division).
Multipoint (Multidrop) Line—Single communications line or circuit interconnecting several stations; usually requires some kind of polling mechanism to address each connected terminal with unique address code.
Multiprocessing—Where operating system allocates different programs and tasks to different processors without intervention by operator, to save considerable time.
Multiprogramming—Ability to run multiple copies of application program on single computer.
MultiProtocol Label Switching (MPLS)—Standard from IETF for including routing information in the packets of an IP network. MPLS is used to ensure that all packets in a particular flow take the same route over a backbone; deployed by many telephone companies and service providers, MPLS can deliver quality of service (QoS) required to support real time voice and video as well as service level agreements (SLAs) that guarantee bandwidth. Large enterprises may also use MPLS in their national networks; once called MultiProtocol Lambda Switching, the earlier name for GMPS; MPLS router attaches labels (tags) containing forwarding information to outgoing IP packets. These "label edge routers" (LERs) sit at the edge of the network and perform the complex packet analysis and classification before the packet enters the core of the network. The routers within the core, known as "label switch routers" (LSRs), quickly examine the label and forward the packet per its directions without having to look up data in tables and compute the forwarding path each time. The edge routers at the receiving end remove the labels.
MultiRead—Specification for CD-ROM and compact disc players that enables them to read discs created by CD-RW drives; developed jointly by Philips Electronics and Hewlett-Packard, and has been approved by the Optical Storage Technology Association (OSTA).
Multitasking—Concurrent execution of two or more tasks or applications by computer at same time, usually separate but interrelated; may also be concurrent execution of single program that is used by many tasks (not always real-time); See Context Switching, Cooperative, and Time-Slice versions; also: clever method of simultaneously slowing down the multitude of computer programs that insist on running too fast. J
Multithreading—In computer programming, multitasking within a single program; allows multiple streams of execution to take place concurrently within same program, each stream processing some different transaction or message; In order for multithreaded program to be of any value, it must be run in multitasking or multiprocessing environment, which allows multiple operations to take place.
Multivariable Control (MC)—Process control of many variables, generally based upon many inputs; usually the term implies need for some advanced control strategy.
MultiVariable Optimization (MVO)—Device supporting this Foundation Fieldbus feature will bundle together view parameters from several function blocks into a single object which can then be transferred in one transaction, greatly reducing traffic on the bus; a significant improvement in refresh time.
MultiVariable Predictive Controller (MVPC)—[Also known as M(B)PC for Model (Based) Predictive Control] In process control, controller that provides complex interaction between all pertinent variables of a unit operation and predicts the optimum operating point for designated targets; intended for processes that have many interacting variables and are the most popular type of optimizer; matrix size is unlimited, but there are practical constraints of processor capacity and performance; see Model Based Predictive Control.
MUMS—MultiUser Management Systems; modern term for role of SCADA systems which give key decision makers ability to analyze system operation to make it more efficient with access to spreadsheets, RDBMS, etc.
MUSIC—Management, User, System, Information, Communications.
MUX—MUltipleXor; I/O device that routes data from several sources to common destination.
MV—Measured Variable, in process control, that variable of process which is monitored by sensor to provide signal to controller, sometimes called Process Variable (PV); also: Manipulated Variable, in process control, quality or condition altered by control action in order to change value of the regulated condition.
MVC— MultiVariable Control(ler).
MVO—MultiVariable Optimization, see definition.
MVPC, MV/PC—MultiVariable Predictive Controller, see definition.
MVS—Machine Vision System.
MXIbus—Multisystem eXtension Interface bus; communications link designed by National Instruments® to connect VXIbus systems.
MXT-Memory eXpansion Technology; IBM hardware implementation of compression algorithms that automatically store frequently accessed data and instructions close to computer's microprocessors so they can be accessed immediately.
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