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22-letter words containing t, u, m, o

  • mathematical induction — induction (def 5).
  • mcculloch-pitts neuron — (artificial intelligence)   The basic building block of artificial neural networks. It receives one or more inputs and produces one or more identical outputs, each of which is a simple non-linear function of the sum of the inputs to the neuron. The non-linear function is typically a threshhold or step function which is usually smoothed (i.e. a sigmoid) to facilitate learning.
  • memory management unit — (hardware, memory management)   (MMU, "Paged Memory Management Unit", PMMU) A hardware device or circuit that supports virtual memory and paging by translating virtual addresses into physical addresses. The virtual address space (the range of addresses used by the processor) is divided into pages, whose size is 2^N, usually a few kilobytes. The bottom N bits of the address (the offset within a page) are left unchanged. The upper address bits are the (virtual) page number. The MMU contains a page table which is indexed (possibly associatively) by the page number. Each page table entry (PTE) gives the physical page number corresponding to the virtual one. This is combined with the page offset to give the complete physical address. A PTE may also include information about whether the page has been written to, when it was last used (for a least recently used replacement algorithm), what kind of processes (user mode, supervisor mode) may read and write it, and whether it should be cached. It is possible that no physical memory (RAM) has been allocated to a given virtual page, in which case the MMU will signal a "page fault" to the CPU. The operating system will then try to find a spare page of RAM and set up a new PTE to map it to the requested virtual address. If no RAM is free it may be necessary to choose an existing page, using some replacement algorithm, and save it to disk (this is known as "paging"). There may also be a shortage of PTEs, in which case the OS will have to free one for the new mapping. In a multitasking system all processes compete for the use of memory and of the MMU. Some memory management architectures allow each process to have its own area or configuration of the page table, with a mechanism to switch between different mappings on a process switch. This means that all processes can have the same virtual address space rather than require load-time relocation. An MMU also solves the problem of fragmentation of memory. After blocks of memory have been allocated and freed, the free memory may become fragmented (discontinuous) so that the largest contiguous block of free memory may be much smaller than the total amount. With virtual memory, a contiguous range of virtual addresses can be mapped to several non-contiguous blocks of physical memory. In early designs memory management was performed by a separate integrated circuit such as the MC 68851 used with the Motorola 68020 CPU in the Macintosh II or the Z8015 used with the Zilog Z80 family of processors. Later CPUs such as the Motorola 68030 and the ZILOG Z280 have MMUs on the same IC as the CPU.
  • methyl isobutyl ketone — a colorless, slightly water-soluble, flammable liquid, C 6 H 1 2 O, having a pleasant odor: used as a solvent for nitrocellulose, gums, resins, fats, waxes, and oils.
  • miscarriage of justice — law: wrongful judgement
  • molecular distillation — a vacuum distillation in which the molecules of the distillate reach the condenser before colliding with one another.
  • monoammonium phosphate — a white, crystalline, moderately water-soluble compound, NH 4 H 2 PO 4 , used as fertilizer, in fire extinguishers, etc.
  • mountain standard time — one of the standard times used in North America, seven hours behind Greenwich Mean Time
  • much ado about nothing — a comedy (1598?) by Shakespeare.
  • mutton dressed as lamb — If you describe a woman as mutton dressed as lamb, you are criticizing her for trying to look younger than she really is, in a way that you consider unattractive.
  • national semiconductor — (company)   A semiconductor manufacturer, responsible for the SC/MP, National Semiconductor 16000 and National Semiconductor 32000 series of microprocessors.
  • nominal semidestructor — (abuse)   Slang for "National Semiconductor", found among other places in the 4.3BSD networking sources. During the late 1970s to mid-1980s this company marketed a series of microprocessors including the National Semiconductor 16000 and National Semiconductor 32000. At one point early in the great microprocessor race, the specs on these chips made them look like serious competition for the rising Intel 80x86 and Motorola 680x0 series. Unfortunately, the actual parts were notoriously flaky and never implemented the full instruction set promised in their literature, apparently because the company couldn't get any of the mask steppings to work as designed. They eventually sank without trace, joining the Zilog Z8000 and a few even more obscure also-rans in the graveyard of forgotten microprocessors.
  • non-euclidean geometry — geometry based upon one or more postulates that differ from those of Euclid, especially from the postulate that only one line may be drawn through a given point parallel to a given line.
  • non-maskable interrupt — (NMI) An IRQ 7 on the PDP-11 or 680x0 or the NMI line on an 80x86. In contrast with a priority interrupt (which might be ignored, although that is unlikely), an NMI is *never* ignored.
  • normal order reduction — Under this evaluation strategy an expression is evaluated by reducing the leftmost outermost redex first. This method will terminate for any expression for which termination is possible, whereas applicative order reduction may not. This method is equivalent to passing arguments unevaluated because arguments are initially to the right of functions applied to them. See also computational adequacy theorem.
  • of the first magnitude — of the greatest importance
  • open network computing — (ONC) Sun's network protocols.
  • ousterhout's dichotomy — (language)   John Ousterhout's division of high-level languages into "system programming languages" and "scripting languages". This distinction underlies the design of his language Tcl. System programming languages (or "applications languages") are strongly typed, allow arbitrarily complex data structures, and programs in them are compiled, and are meant to operate largely independently of other programs. Prototypical system programming languages are C and Modula-2. By contrast, scripting languages (or "glue languages") are weakly typed or untyped, have little or no provision for complex data structures, and programs in them ("scripts") are interpreted. Scripts need to interact either with other programs (often as glue) or with a set of functions provided by the interpreter, as with the file system functions provided in a UNIX shell and with Tcl's GUI functions. Prototypical scripting languages are AppleScript, C Shell, MS-DOS batch files and Tcl. Many believe that this is a highly arbitrary dichotomy, and refer to it as "Ousterhout's fallacy" or "Ousterhout's false dichotomy". While strong-versus-weak typing, data structure complexity, and independent versus stand-alone might be said to be unrelated features, the usual critique of Ousterhout's dichotomy is of its distinction of compilation versus interpretation, since neither semantics nor syntax depend significantly on whether code is compiled into machine-language, interpreted, tokenized, or byte-compiled at the start of each run, or any mixture of these. Many languages fall between being interpreted or compiled (e.g. Lisp, Forth, UCSD Pascal, Perl, and Java). This makes compilation versus interpretation a dubious parameter in a taxonomy of programming languages.
  • philip the magnanimous — 1504–67, German prince; landgrave of Hesse (1509–67). He helped to crush (1525) the Peasants' Revolt and formed (1531) the League of Schmalkaden, an alliance of German Protestant rulers
  • pneumocystis pneumonia — a pulmonary infection caused by the protozoan Pneumocystis carinii, occurring as an opportunistic disease in persons with impaired immune systems, as AIDS victims. Abbreviation: PCP.
  • polymyalgia rheumatica — a chronic inflammatory disease, common among older persons, characterized by recurrent episodes of muscle pain and stiffness, sometimes leading to cardiovascular complications or blindness.
  • potassium ferricyanide — a bright-red, crystalline, water-soluble, poisonous solid, K 3 Fe(CN) 6 , used chiefly in the manufacture of pigments, as Prussian blue, and of paper, especially blueprint paper.
  • potassium ferrocyanide — a lemon-yellow, crystalline, water-soluble solid, K 4 Fe(CN) 6 ⋅3H 2 O, used chiefly in casehardening alloys having an iron base and in dyeing wool and silk.
  • potassium permanganate — a very dark purple, crystalline, water-soluble solid, KMnO 4 , used chiefly as an oxidizing agent, disinfectant, laboratory reagent, and in medicine as an astringent and antiseptic.
  • potassium-argon dating — a method for estimating the age of a mineral or rock, based on measurement of the rate of decay of radioactive potassium into argon.
  • private-equity company — an organization that uses private equity to gain control of and manage companies
  • procurement department — the department of (a company, organization, etc) responsible for purchasing and buying
  • productivity agreement — an agreement whereby the employees of an organization agree to changes which are intended to improve productivity in return for an increase in pay or other benefits
  • programmed instruction — a progressively monitored, step-by-step teaching method, employing small units of information or learning material and frequent testing, whereby the student must complete or pass one stage before moving on to the next.
  • public domain software — public domain
  • public limited company — A public limited company is the same as a public company. The abbreviation plc is used after such companies' names.
  • pulmonary tuberculosis — tuberculosis of the lungs.
  • quantum chromodynamics — a quantum field theory that describes quarks and gluons and their interactions, with the color of the quarks playing a role analogous to that of electric charge. Abbreviation: QCD. Also called chromodynamics. Compare color (def 18).
  • read someone a lecture — to scold or reprimand someone
  • recruitment consultant — A recruitment consultant is a person or service that helps professional people to find work by introducing them to potential employers.
  • reliable communication — (communications)   Communication where messages are guaranteed to reach their destination complete and uncorrupted and in the order they were sent. This reliability can be built on top of an unreliable protocol by adding sequencing information and some kind of checksum or cyclic redundancy check to each message or packet. If the communication fails, the sender will be notified. Transmission Control Protocol is a reliable protocol used on Ethernet.
  • revolutions per minute — (unit)   (rpm, rarely: rotations per minute) A unit of angular velocity equal to 1/60 of a revolution per second.
  • rheumatoid spondylitis — ankylosing spondylitis.
  • rocky mountain bighorn — bighorn.
  • rocky mountain juniper — a juniper, Juniperus scopulorum, of western North America, that yields a soft, reddish wood used for making fences, pencils, etc., and that is also grown as an ornamental.
  • rocky mountain oysters — mountain oyster.
  • sales force automation — (business)   (Sales Automation, SFA, SFFA, Sales & Field Force Automation) Software to support sales reps. The software gives sales representitives access to contacts, appointments and e-mail. It is likely to be integrated with Customer Relationship Management systems and Opportunity Management Systems.
  • sarcoplasmic reticulum — a system of membrane-bound tubules that surrounds muscle fibrils, releasing calcium ions during contraction and absorbing them during relaxation.
  • simultaneous broadcast — a programme, etc, broadcast simultaneously on radio and television
  • simultaneous equations — a set of two or more equations, each containing two or more variables whose values can simultaneously satisfy both or all the equations in the set, the number of variables being equal to or less than the number of equations in the set.
  • small business edition — Microsoft Office Small Business Edition
  • social security number — A Social Security number is a nine digit number that is given to U.S. citizens and to people living in the U.S. You need it to get a job, collect Social Security benefits and receive some government services.
  • solid dose formulation — A solid dose formation is a hard tablet made by compressing medicine in a powder form.
  • somatic nervous system — the section of the nervous system responsible for sensation and control of the skeletal muscles
  • spontaneous combustion — the ignition of a substance or body from the rapid oxidation of its own constituents without heat from any external source.
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