Technology terms starting with H

472 terms

  1. HBA Host Bus Adapter. Any hardware bridge between a storage interconnect and a system's I/O bus.
  2. HBA (Host Bus Adapter) "Host Bus Adapter", connects a host system (the computer) toother network and storage devices.
  3. HBCU/MI Historically Black Colleges and Universities/Minority Institutions.
  4. HBHO Hard-body Hand-over [algorithms].
  5. HCAP A protocol used by Access Control Server (ACS) to send and receive statements of health to and from other NAP infrastructure components.
  6. HCD (Hardware Configuration Definition) an interactive interface that enables an installation to define I/O configurations to both the software and hardware from one interface.
  7. HCEP The protocol used by the NAP agent to request health certificates from the Health Registration Authority (HRA) and to prove the health of a client…
  8. HCO High Consequence Option (Safety Engineering term).
  9. HCT Mercury Cadmium Telluride.
  10. HDA Hybrid Detector Assembly.
  11. HDA (Head/Disk Assembly) a sealed Winchester assembly, including disks, heads, filter and actuator assembly.
  12. HDBK Handbook.
  13. HDD (Hard Disk Drive) , also called a Winchester drive, is a spinning magnetic disk accessed by a flying head.
  14. HDLC Abbreviation for high-level data link control.
  15. HDR An amount of radiation that is greater than that given in typical radiation therapy.
  16. HDTV Abbreviation for high-definition television.
  17. HDX Half Duplex ( TelComm /Computer term).
  18. HE (1) High Explosive. (2) High Energy.
  19. HE11 mode Designation for the fundamental hybrid mode of an optical fiber.
  20. Head The upper horizontal part of a window frame or window opening.
  21. Head clog Debris trapped in the playback head of a video recorder. Clogging of the playback head with debris causes dropouts.
  22. head end See cable headend, headend.
  23. head-of-bus function The function that generates management information and empty bus slots at the point on each bus where data flow begins.
  24. head-on collision A collision that occurs on a communications channel when two or more users begin to transmit on the channel at approximately the same instant.
  25. headend A central control device required by some networks (e.g., LANs or MANs) to provide such centralized functions as remodulation, retiming, message…
  26. Header A masonry wall unit of brick which is laid so that its short end is exposed.
  27. header check sequence (HCS) A 16-bit cyclic redundancy check (CRC) check sequence (CS) that is derived from bits from the first 8 octets (excluding flags) of a UIH format packet. [T1.
  28. header file A file containing certain required definitions that you must include "ahead" of the rest of your program to do certain obscure operations.
  29. Heading In a tunnel, a digging face and its work area.
  30. Heading tag An HTML tag that is often used to denote a page or section heading on a web page.
  31. Headings The heading element briefly describes the subject of the section it introduces.
  32. headless Describes a program or application that runs in the background without any interface connected to it.
  33. Headline The title of an article or story.
  34. Health Health services, human ecology, and safety. For example, resources describing human disease and illness, factors affecting health, hygiene, mental and…
  35. Health and Status (H&S) Health and Status pertains to a units ability to assess the conditions of its subsystem functions.
  36. health certificate An X.509 certificate that asserts the health of a client computer. Client computers can use this certificate to prove their identities and health through…
  37. Health Certificate Enrollment Protocol The protocol used by the NAP agent to request health certificates from the Health Registration Authority (HRA) and to prove the health of a client…
  38. health check A system call to check on the health status of each instance in an Auto Scaling group.
  39. health policy A collection of software requirements, security update requirements, and required configuration settings for NAP client computers.
  40. Health Registration Authority A component of Network Access Protection (NAP) that validates statements of health (SoHs) and approves the issuance of a health certificate to clients…
  41. health requirement server A software component that communicates with a Network Policy Server (NPS) and provides information that system health agents (SHAs) use to validate…
  42. Healthy One of four health states of a storage group copy. Healthy indicates that the passive copy of a storage group can be advanced by log replay.
  43. heartbeat A repeating signal transmitted from one appliance to another that indicates that the appliance is in operation.
  44. heartbeat interval The amount of time that can elapse before the Exchange server asks a mobile device running Exchange ActiveSync to connect again. [Exchange 2007]
  45. heartbeat network A network that provides reliable communication among nodes in a cluster, including the transmission of heartbeat messages, signals from each functioning…
  46. Heaviside layer Synonym E region.
  47. Heavy Replicas (HREPS) Decoys, which by virtue of shape, size, and mass, closely approximate an RVs signature. HREPS have significant off- load penalty.
  48. HEDI OBSOLETE. See High Endoatmospheric Defense Interceptor.
  49. HEDR High Endoatmospheric Defense Radar.
  50. HEDS High Endoatmospheric Defense System.
  51. HEI High Endoatmospheric Interceptor.
  52. height gain For a given propagation mode of an electromagnetic wave, the ratio of the field strength at a specified height to the field strength at the surface of the…
  53. HEL High Energy Laser.
  54. helical antenna An antenna that has the form of a helix. Note: When the helix circumference is much smaller than one wavelength, the antenna radiates at right angles to…
  55. helical scan A method of recording video information diagonally on a tape, used in home and professional video cassette recorders (VCRs).
  56. Helical scan recording The recording format in which a slow moving tape is helically wrapped 180° around a rapidly rotating drum with a small embedded record head.
  57. HELKS High Energy Laser Kill System.
  58. HELLO High Energy Laser Light Opportunity.
  59. HELSTF High Energy Laser Systems Test Facility.
  60. HELWS High Energy Laser Weapon System.
  61. HEMP High Altitude Electromagnetic Pulse. 126
  62. HEMTT Heavy Expanded Mobility Tactical Truck (US Army prime mover).
  63. Hen House Soviet area defense radar used as a component of the Moscow ABM system that provides VHF coverage of space to monitor orbiting satellites and early…
  64. HEO See High Earth Orbit.
  65. HERA (1) An improved surrogate TBM test target. (2) Two-stage, ground launched solid propellant theater target vehicle. (MDA Lexicon)
  66. here document So called because of a similar construct in shells that pretends that the lines following the "command" are a separate "file" to be fed to the command, up…
  67. HERF Abbreviation for hazards of electromagnetic radiation to fuel.
  68. HERO Hazards of Electromagnetic Radiation to Ordnance (SM-2 Bk IVA).
  69. HERP Abbreviation for hazards of electromagnetic radiation to personnel.
  70. Hertz (Hz) The unit of measurement of frequency, equivalent to one cycle per second.
  71. Hertzian wave Synonym radio wave.
  72. HESP High Efficiency Solar Panel.
  73. heterochronous A relationship between two signals such that their corresponding significant instants do not necessarily occur at the same time.
  74. heterodyne To generate new frequencies by mixing two or more signals in a nonlinear device such as a vacuum tube, transistor, or diode mixer.
  75. heterodyne repeater In radio reception and retransmission, a repeater that converts the original band of frequencies of the received signal to a different frequency band for…
  76. heterogeneous collection A collection of objects with different dynamic types. See homogeneous collection.
  77. heterogeneous multiplexing Multiplexing in which not all the information-bearer channels operate at the same data signaling rate.
  78. Heterogeneous Network A network that includes computers and other devices that run different operating systems.
  79. HEU Highly Enriched Uranium.
  80. heuristic A computational method that uses trial and error methods to approximate a solution for computationally difficult problems.
  81. heuristic attribute This attribute enables envelope journaling at the Exchange organizational level.
  82. heuristic routing Routing in which data, such as time delay, extracted from incoming messages, during specified periods and over different routes, are used to determine the…
  83. hexadecimal A number system with a base of 16. The digits are 0-9 and A-F, where F equals the decimal value of 15.
  84. HF (1) High Frequency. (2) Hydrogen fluoride.
  85. HF/DF (1) High Frequency/Direction Finding. (2) Hydrogen Fluoride/Deuterium Fluoride. (Chemicals used in IR chemical lasers).
  86. HFCNR High Frequency Combat Net Radio.
  87. HFDF Abbreviation for high-frequency distribution frame.
  88. HFE Human Factors Engineering.
  89. HgCdTe Mercury Cadmium Telluride.
  90. HHB Headquarters and Headquarters Battery.
  91. hibernation A power-saving feature that saves everything in memory on disk, turns off your monitor and hard disk, and then turns off your computer.
  92. hibernation file A file created during hibernation that contains all CPU memory and registers information.
  93. HIBEX High-Acceleration Boost Experiment.
  94. HIBREL High Brightness Relay.
  95. HIC Hydrologist In Charge
  96. HICOM High Command (Navy term).
  97. HICTB Human-in-Control Test Bed.
  98. HIDACZ High Density Aerospace Control Zone.
  99. HIDAR High Data Rate.
  100. Hidden keywords Keywords that are placed in the HTML source in such a way that these words are not viewable by human visitors looking at the rendered web page.