1.
Decimal
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This article aims to be an accessible introduction. For the mathematical definition, see Decimal representation, the decimal numeral system has ten as its base, which, in decimal, is written 10, as is the base in every positional numeral system. It is the base most widely used by modern civilizations. Decimal fractions have terminating decimal representations and other fractions have repeating decimal representations, Decimal notation is the writing of numbers in a base-ten numeral system. Examples are Brahmi numerals, Greek numerals, Hebrew numerals, Roman numerals, Roman numerals have symbols for the decimal powers and secondary symbols for half these values. Brahmi numerals have symbols for the nine numbers 1–9, the nine decades 10–90, plus a symbol for 100, Chinese numerals have symbols for 1–9, and additional symbols for powers of ten, which in modern usage reach 1072. Positional decimal systems include a zero and use symbols for the ten values to represent any number, positional notation uses positions for each power of ten, units, tens, hundreds, thousands, etc. The position of each digit within a number denotes the multiplier multiplied with that position has a value ten times that of the position to its right. There were at least two independent sources of positional decimal systems in ancient civilization, the Chinese counting rod system. Ten is the number which is the count of fingers and thumbs on both hands, the English word digit as well as its translation in many languages is also the anatomical term for fingers and toes. In English, decimal means tenth, decimate means reduce by a tenth, however, the symbols used in different areas are not identical, for instance, Western Arabic numerals differ from the forms used by other Arab cultures. A decimal fraction is a fraction the denominator of which is a power of ten. g, Decimal fractions 8/10, 1489/100, 24/100000, and 58900/10000 are expressed in decimal notation as 0.8,14.89,0.00024,5.8900 respectively. In English-speaking, some Latin American and many Asian countries, a period or raised period is used as the separator, in many other countries, particularly in Europe. The integer part, or integral part of a number is the part to the left of the decimal separator. The part from the separator to the right is the fractional part. It is usual for a number that consists only of a fractional part to have a leading zero in its notation. Any rational number with a denominator whose only prime factors are 2 and/or 5 may be expressed as a decimal fraction and has a finite decimal expansion. 1/2 =0.5 1/20 =0.05 1/5 =0.2 1/50 =0.02 1/4 =0.25 1/40 =0.025 1/25 =0.04 1/8 =0.125 1/125 =0.008 1/10 =0
2.
United States Department of Defense
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The Department is the largest employer in the world, with nearly 1.3 million active duty servicemen and women as of 2016. Adding to its employees are over 801,000 National Guardsmen and Reservists from the four services and it is headquartered at the Pentagon in Arlington, Virginia, just outside of Washington, D. C. The Department of Defense is headed by the Secretary of Defense, Military operations are managed by nine regional or functional Unified Combatant Commands. The Department of Defense also operates several joint services schools, including the National Defense University, the history of the defense of the United States started with the Continental Congress in 1775. The creation of the United States Army was enacted on 14 June 1775 and this coincides with the American holiday Flag Day. The Second Continental Congress would charter the United States Navy, on 13 October 1775, today, both the Navy and the Marine Corps are separate military services subordinate to the Department of the Navy. The Preamble of the United States Constitution gave the authority to federal government, to defend its citizens and this first Congress had a huge agenda, that of creating legislation to build a government for the ages. Legislation to create a military defense force stagnated, two separate times, President George Washington went to Congress to remind them of their duty to establish a military. In a special message to Congress on 19 December 1945, the President cited both wasteful military spending and inter-departmental conflicts, deliberations in Congress went on for months focusing heavily on the role of the military in society and the threat of granting too much military power to the executive. The act placed the National Military Establishment under the control of a single Secretary of Defense, the National Military Establishment formally began operations on 18 September, the day after the Senate confirmed James V. Forrestal as the first Secretary of Defense. The National Military Establishment was renamed the Department of Defense on 10 August 1949, under the Department of Defense Reorganization Act of 1958, channels of authority within the department were streamlined, while still maintaining the authority of the Military Departments. Also provided in this legislation was a centralized authority, the Advanced Research Projects Agency. The Act moved decision-making authority from the Military Departments to the Joint Chiefs of Staff and it also strengthened the command channel of the military over U. S. forces from the President to the Secretary of Defense. Written and promoted by the Eisenhower administration, it was signed into law 6 August 1958, because the Constitution vests all military authority in Congress and the President, the statutory authority of the Secretary of Defense is derived from their constitutional authorities. Department of Defense Directive 5100.01 describes the relationships within the Department. The latest version, signed by former Secretary of Defense Robert Gates in December 2010, is the first major re-write since 1987, the Office of the Secretary of Defense is the Secretary and Deputy Secretarys civilian staff. S. Government departments and agencies, foreign governments, and international organizations, OSD also performs oversight and management of the Defense Agencies and Department of Defense Field Activities. OSD also supervises the following Defense Agencies, Several defense agencies are members of the United States Intelligence Community and these are national-level intelligence services that operate under the jurisdiction of the Department of Defense but simultaneously fall under the authorities of the Director of National Intelligence
3.
Lockheed Martin F-22 Raptor
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The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force. The aircraft was variously designated F-22 and F/A-22 before it entered service in December 2005 as the F-22A. The Raptors combination of stealth, aerodynamic performance, and situational awareness gives the aircraft unprecedented air combat capabilities, a final procurement tally of 187 operational production aircraft was established in 2009, and the last F-22 was delivered to the USAF in 2012. In 1981 the U. S. Air Force developed a requirement for an Advanced Tactical Fighter as a new air superiority fighter to replace the F-15 Eagle and F-16 Fighting Falcon. Code named Senior Sky, this program was influenced by the emerging threats, including development and proliferation of Soviet Su-27 Flanker-. Each design team produced two prototype air vehicles, one for each of the two engine options, the Lockheed-led team employed thrust vectoring nozzles on YF-22 for enhanced maneuverability in dogfights. The ATFs increasing weight and cost drove out certain requirements during development, side-looking radars were deleted, and the dedicated infra-red search and track system was downgraded from multi-color to single color and then deleted as well. However, space and cooling provisions were retained to allow for future addition of these components, the ejection seat requirement was downgraded from a fresh design to the existing McDonnell Douglas ACES II. After the flight test demonstration and validation of the prototypes, on 23 April 1991, the YF-23 design was considered stealthier and faster, while the YF-22 was more maneuverable. The aviation press speculated that the YF-22 was also adaptable to the U. S. Navys Navalized Advanced Tactical Fighter, but by 1992. F-22 production was split up over many subcontractors across 46 states to increase Congressional support, though this production split may have contributed to increased costs, many capabilities were deferred to post-service upgrades, reducing the initial cost but increasing total program cost. Production supported over 1,000 subcontractors and suppliers and up to 95,000 jobs, the F-22 had several design changes from the YF-22. The swept-back angle of the edge was decreased from 48° to 42°, while the vertical stabilizers were shifted rearward. To improve pilot visibility, the canopy was moved forward 7 inches, the shapes of the wing and stabilator trailing edges were refined to improve aerodynamics, strength, and stealth characteristics. Increasing weight during development caused slight reductions in range and aerodynamic performance, the first F-22, an engineering and manufacturing development aircraft named Raptor 4001, was unveiled at Marietta, Georgia, on 9 April 1997, and first flew on 7 September 1997. In 2006, the Raptors development team, composed of over 1,000 contractors, the F-22 was in production for 15 years, at a rate of roughly two per month during peak production. The USAF originally envisioned ordering 750 ATFs at a cost of $26.2 billion, the 1990 Major Aircraft Review led by Secretary of Defense Dick Cheney reduced this to 648 aircraft beginning in 1996. By 1997, funding instability had further cut the total to 339, in 2004, the Department of Defense further reduced this to 183 operational aircraft, despite the USAFs preference for 381
4.
Fault tree analysis
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Fault tree analysis is a top down, deductive failure analysis in which an undesired state of a system is analyzed using Boolean logic to combine a series of lower-level events. FTA is also used in engineering for debugging purposes and is closely related to cause-elimination technique used to detect bugs. In aerospace, the general term system Failure Condition is used for the undesired state / Top event of the fault tree. These conditions are classified by the severity of their effects, the most severe conditions require the most extensive fault tree analysis. These system Failure Conditions and their classification are often determined in the functional Hazard analysis. Fault Tree Analysis can be used to, understand the logic leading to the top event / undesired state, show compliance with the system safety / reliability requirements. Prioritize the contributors leading to the top event - Creating the Critical Equipment/Parts/Events lists for different importance measures, monitor and control the safety performance of the complex system. The FTA can be used as a tool that helps to create requirements. Function as a tool to identify and correct causes of the top event. It can help with the creation of diagnostic manuals / processes, Fault Tree Analysis was originally developed in 1962 at Bell Laboratories by H. A. Watson, under a U. S. Air Force Ballistics Systems Division contract to evaluate the Minuteman I Intercontinental Ballistic Missile Launch Control System, the use of fault trees has since gained widespread support and is often used as a failure analysis tool by reliability experts. Following the first published use of FTA in the 1962 Minuteman I Launch Control Safety Study, Boeing, FTA received extensive coverage at a 1965 System Safety Symposium in Seattle sponsored by Boeing and the University of Washington. Boeing began using FTA for civil aircraft design around 1966, subsequently, within the U. S. military, application of FTA for use with fuzes was explored by Picatinny Arsenal in the 1960s and 1970s. In 1976 the U. S. Army Materiel Command incorporated FTA into an Engineering Design Handbook on Design for Reliability, mIL-HDBK-338B provides a more recent reference. In 1970, the U. S. Federal Aviation Administration published a change to 14 CFR25.1309 airworthiness regulations for transport aircraft in the Federal Register at 35 FR5665. This change adopted failure probability criteria for aircraft systems and equipment and this led to the publication of the FAA System Safety Handbook, which describes the use of FTA in various types of formal hazard analysis. Early in the Apollo project the question was asked about the probability of successfully sending astronauts to the moon, a risk, or reliability, calculation of some sort was performed and the result was a mission success probability that was unacceptably low. This result discouraged NASA from further quantitative risk or reliability analysis until after the Challenger accident in 1986, instead, NASA decided to rely on the use of failure modes and effects analysis and other qualitative methods for system safety assessments
5.
Systems engineering
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Systems engineering is an interdisciplinary field of engineering and engineering management that focuses on how to design and manage complex systems over their life cycles. At its core systems engineering utilizes systems thinking principles to organize this body of knowledge, Systems engineering deals with work-processes, optimization methods, and risk management tools in such projects. Systems engineering ensures that all aspects of a project or system are considered. The systems engineering process is a process that is quite unlike a manufacturing process. A manufacturing process is focused on activities that achieve high quality outputs with minimum cost. The term systems engineering can be traced back to Bell Telephone Laboratories in the 1940s. S, the continuing evolution of systems engineering comprises the development and identification of new methods and modeling techniques. These methods aid in the comprehension and the design and development control of engineering systems as they grow more complex. Popular tools that are used in the systems engineering context were developed during these times, including USL, UML, QFD. In 1990, a society for systems engineering, the National Council on Systems Engineering, was founded by representatives from a number of U. S. corporations and organizations. NCOSE was created to address the need for improvements in engineering practices. As a result of growing involvement from systems engineers outside of the U. S. the name of the organization was changed to the International Council on Systems Engineering in 1995. Schools in several countries offer programs in systems engineering. Systems engineering signifies only an approach and, more recently, a discipline in engineering, as an approach, systems engineering is holistic and interdisciplinary in flavour. The traditional scope of engineering embraces the conception, design, development, Systems engineering, as originally conceived, falls within this scope. The Apollo program is an example of a systems engineering project. The use of the systems engineer has evolved over time to embrace a wider, more holistic concept of systems. This evolution of the definition has been a subject of ongoing controversy, traditional systems engineering was seen as a branch of engineering in the classical sense, that is, as applied only to physical system, such as space craft and aircraft. More recently, systems engineering has evolved to a take on a broader meaning especially when humans were seen as a component of a system
6.
Power station
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A power station, also referred to as a power plant or powerhouse and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Most power stations contain one or more generators, a machine that converts mechanical power into electrical power. The relative motion between a field and a conductor creates an electrical current. The energy source harnessed to turn the generator varies widely, most power stations in the world burn fossil fuels such as coal, oil, and natural gas to generate electricity. Others use nuclear power, but there is an use of cleaner renewable sources such as solar, wind, wave. There is some debate within utility and engineering circles over whether a solar array, or wind farm, should be referred to as a power station, in 1868 a hydro electric power station was designed and built by Lord Armstrong at Cragside, England. It used water from lakes on his estate to power Siemens dynamos, the electricity supplied power to lights, heating, produced hot water, ran an elevator as well as labor-saving devices and farm buildings. In the early 1870s Belgian inventor Zénobe Gramme invented a powerful enough to produce power on a commercial scale for industry. In the autumn of 1882, a central station providing public power was built in Godalming and it was proposed after the town failed to reach an agreement on the rate charged by the gas company, so the town council decided to use electricity. It used hydroelectric power that was used to street and household lighting, the system was not a commercial success and the town reverted to gas. In 1882 a the worlds first coal-fired public power station, the Edison Electric Light Station, was built in London, a Babcock & Wilcox boiler powered a 125-horsepower steam engine that drove a 27-ton generator. This supplied electricity to premises in the area that could be reached through the culverts of the viaduct without digging up the road, the customers included the City Temple and the Old Bailey. Another important customer was the Telegraph Office of the General Post Office, Johnson arranged for the supply cable to be run overhead, via Holborn Tavern and Newgate. In September 1882 in New York, the Pearl Street Station was established by Edison to provide lighting in the lower Manhattan Island area. The station ran until destroyed by fire in 1890, the station used reciprocating steam engines to turn direct-current generators. Because of the DC distribution, the area was small. The War of Currents eventually resolved in favor of AC distribution and utilization, DC systems with a service radius of a mile or so were necessarily smaller, less efficient of fuel consumption, and more labor-intensive to operate than much larger central AC generating stations. AC systems used a range of frequencies depending on the type of load, lighting load using higher frequencies
7.
Safety engineering
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Safety engineering is an engineering discipline which assures that engineered systems provide acceptable levels of safety. It is strongly related to industrial engineering, and the subset system safety engineering. Safety engineering assures that a system behaves as needed, even when components fail. Analysis techniques can be split into two categories, qualitative and quantitative methods, both approaches share the goal of finding causal dependencies between a hazard on system level and failures of individual components. Qualitative approaches focus on the question What must go wrong, such that a system hazard may occur, while quantitative methods aim at providing estimations about probabilities, rates and/or severity of consequences. The complexity of the technical systems such as Improvements of Design and Materials, Planned Inspections, Fool-proof design, the risk can be decreased to ALARA or ALAPA levels. Traditionally, safety analysis techniques rely solely on skill and expertise of the safety engineer, in the last decade model-based approaches have become prominent. In contrast to methods, model-based techniques try to derive relationships between causes and consequences from some sort of model of the system. The two most common fault modeling techniques are called failure mode and effects analysis and fault tree analysis and these techniques are just ways of finding problems and of making plans to cope with failures, as in probabilistic risk assessment. One of the earliest complete studies using this technique on a nuclear plant was the WASH-1400 study. Failure Mode and Effects Analysis is a bottom-up, inductive analytical method which may be performed at either the functional or piece-part level, for functional FMEA, failure modes are identified for each function in a system or equipment item, usually with the help of a functional block diagram. For piece-part FMEA, failure modes are identified for each piece-part component, the effects of the failure mode are described, and assigned a probability based on the failure rate and failure mode ratio of the function or component. This quantiazation is difficult for software ---a bug exists or not, temperature and age and manufacturing variability affect a resistor, they do not affect software. Failure modes with identical effects can be combined and summarized in a Failure Mode Effects Summary, when combined with criticality analysis, FMEA is known as Failure Mode, Effects, and Criticality Analysis or FMECA, pronounced fuh-MEE-kuh. Fault tree analysis is a top-down, deductive analytical method, the intent is to identify ways to make top events less probable, and verify that safety goals have been achieved. Fault trees are a logical inverse of success trees, and may be obtained by applying de Morgans theorem to success trees, FTA may be qualitative or quantitative. When failure and event probabilities are unknown, qualitative fault trees may be analyzed for minimal cut sets, for example, if any minimal cut set contains a single base event, then the top event may be caused by a single failure. Some industries use both trees and event trees
8.
General Services Administration
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The General Services Administration is an independent agency of the United States government, established in 1949 to help manage and support the basic functioning of federal agencies. GSA employs about 12,000 federal workers and has an operating budget of roughly $26.3 billion. GSA oversees $66 billion of procurement annually and it contributes to the management of about $500 billion in U. S. federal property, divided chiefly among 8,300 owned and leased buildings and a 210,000 vehicle motor pool. GSAs business lines include the Federal Acquisition Service, the Public Buildings Service, the GSA is member of the Procurement G6, an informal group leading the use of framework agreements and e-procurement instruments in public procurement. In 1947 President Harry Truman asked former President Herbert Hoover to lead what became known as the Hoover Commission to make recommendations to reorganize the operations of the federal government, one of the recommendations of the commission was the establishment of an Office of the General Services. This proposed office would combine the responsibilities of the following organizations, General Jess Larson, Administrator of the War Assets Administration, was named GSAs first Administrator. The first job awaiting Administrator Larson and the newly formed GSA was a renovation of the White House. The structure had fallen into such a state of disrepair by 1949 that one inspector of the time said the structure was standing “purely from habit. Everything, except the four walls without a roof, was stripped down. GSA completed the renovation in 1952, GSA headquarters, located at Eighteenth and F Streets, NW, was U. S. General Services Administration Building listed on the National Register of Historic Places in 1986 as Interior Department Offices, in 1960, GSA created the Federal Telecommunications System, a government-wide intercity telephone system. In 1970, the Nixon administration created the Consumer Product Information Coordinating Center, the Federal Buildings Fund was initiated in 1974, which allowed the GSA to issue rent bills to federal agencies. In 1972, the GSA established the Automated Data and Telecommunications Service, in 1973, the GSA created the Office of Federal Management Policy. GSA’s Office of Acquisition Policy centralized procurement policy in 1978, in 1984, GSA introduced the federal government to the use of charge cards, known as the GMA SmartPay system. The National Archives and Records Administration was spun off into an independent agency in 1985, the same year, the GSA began to provide governmentwide policy oversight and guidance for federal real property management as a result of an Executive Order signed by President Ronald Reagan. In 2003, the Federal Protective Service was moved to the Department of Homeland Security, in 2005, GSA reorganized to merge the Federal Supply Service and Federal Technology Service business lines into the Federal Acquisition Service. On April 3,2009, President Barack Obama nominated Martha N. Johnson to serve as the GSA Administrator, after a 9-month delay, the United States Senate confirmed her nomination on February 4,2010. In July 1991, GSA contractors began the excavation of what is now the Ted Weiss Federal Building in New York City, when initial excavation disturbed burials, destroying skeletons and artifacts, GSA sent archaeologists to excavate—but hid their findings from the public
9.
North American Electric Reliability Corporation
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The original NERC was formed on June 1,1968, by the electric utility industry to promote the reliability and adequacy of bulk power transmission in the electric utility systems of North America. NERCs mission states that it is to ensure the reliability of the North American bulk power system, NERC oversees eight regional reliability entities and encompasses all of the interconnected power systems of the contiguous United States, Canada and a portion of Baja California in Mexico. NERC also investigates and analyzes the causes of significant power system disturbances in order to prevent future events. The name was changed from Council to Corporation in 2007, the ES-ISAC, which changed its name in 2015 to Electricity Information Sharing and Analysis Center, shares timely information with industry through its secure web portal. In August,2003, North America experienced its worst blackout to date, as 50 million people lost power in the Northeastern and Midwestern United States and Ontario, Canada. A United States–Canada Power System Outage Task Force was formed to investigate the causes of the blackout, the Energy Policy Act of 2005 called for the creation of an Electric Reliability Organization to develop and enforce compliance with mandatory reliability standards in the United States. This non-governmental, self-regulatory organization was created in recognition of the interconnected, in April 2006, NERC applied for and was granted the designation of the ERO by FERC in July 2006. FERC approved 83 NERC Reliability Standards in March 2007, making them the first set of legally enforceable standards for the U. S. bulk power system effective on June 2007. Although significant disturbances continued to occur, the formation of an ERO undoubtedly played a significant role in minimizing the impact. As these systems grew to cover larger areas, it became possible to connect previously isolated systems, allowing neighboring systems to share generation. However, tying power systems together with these early interconnections also introduced the risk that a significant disturbance could collapse all of the systems tied to the interconnection. Generally, it was decided that the benefits outweighed the risks, by the end of the 1960s, there were virtually no isolated power systems remaining in the lower 48 states and southern Canada, practically all power companies were attached to large interconnections. Unlike water or gas, electricity cannot be stored in large quantities and it must be generated at the instant it is used, which requires supply be kept in constant balance with demand. This requires the cooperation and coordination of hundreds of electricity industry participants, NERC defines the reliability of the interconnected bulk power system in terms of two basic and functional aspects, Adequacy. Regarding adequacy, system operators can and should take “controlled” actions or procedures to maintain a balance between supply and demand within a Balancing Area. All other system disturbances that result in the unplanned and/or uncontrolled interruption of customer demand, regardless of cause, when these interruptions are contained within a localized area, they are considered unplanned interruptions or disturbances. When they spread over an area of the grid, they are referred to as cascading outages — the uncontrolled successive loss of system elements triggered by an incident at any location. Cascading results in widespread service interruption, what occurred in the Northeast in 2003 and in the Southwest in 2011 were uncontrolled, cascading outages
10.
Spare part
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A spare part, spare, service part, repair part, or replacement part, is an interchangeable part that is kept in an inventory and used for the repair or replacement of failed units. Spare parts are an important feature of logistics engineering and supply chain management, spare parts are an outgrowth of the industrial development of interchangeable parts and mass production. In logistics, spare parts can be classified into two groups, repairables and consumables. Economically, there is a tradeoff between the cost of ordering a replacement part and the cost of repairing a failed part, when the cost of repair becomes a significant percentage of the cost of replacement, it becomes economically favorable to simply order a replacement part. In such cases, the part is said to be beyond repair. Analysis of economic tradeoffs is formally evaluated using Level of Repair Analysis, repairable parts are parts that are deemed worthy of repair, usually by virtue of economic consideration of their repair cost. Rather than bear the cost of replacing a finished product. This allows components to be easily removed, repaired, and replaced. Spare parts that are needed to support condemnation of repairable parts are known as replenishment spares, a rotable pool is a pool of repairable spare parts inventory set aside to allow for multiple repairs to be accomplished simultaneously. This can be used to minimize stockout conditions for repairable items, parts that are not repairable, are considered consumable parts. Consumable parts are usually scrapped, or condemned, when they are found to have failed, since no attempt at repair is made, for a fixed mean time between failures, replacement rates for consumption of consumables are higher than an equivalent item treated as a repairable part. Because of this, consumables tend to be lower cost items, because consumables are lower cost and higher volume, economies of scale can be found by ordering in large lot sizes, a so-called Economic order quantity. From the perspective of logistics, a model of the cycle of parts in a supply chain can be developed. Ultimately, this ends with the manufacturer. This type of model allows demands on a system to ultimately be traced to their operational reliability, allowing for analysis of the dynamics of the supply system, in particular. When stockout conditions occur, cannibalization can result and this is the practice of removing parts or subsystems necessary for repair from another similar device, rather than from inventory. The source system is crippled as a result, if only temporarily. As a result, operational availability is impaired, industrialization has seen the widespread growth of commercial manufacturing enterprises, such as the automotive industry, and later, the computer industry
11.
MIL-STD-188
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MIL-STD-188 is a series of U. S. military standards relating to telecommunications. S. Department of Defense looked to develop a series of standards that would alleviate the problem, … systems developed for use by U. S. forces are considered to be for joint use. The MIL-STD-188 standards were created to address telecommunication design parameters based on proven technologies, to ensure interoperability, DISA made these standards mandatory for use in all new DoD systems and equipment, or major upgrades. The mandatory use of standards will aid significantly in achieving standardization and result in improvements in availability, maintainability, reliability. This, in turn, will enhance lifecycle configuration management and logistic support with subsequent reductions in life cycle costs, in line with a decision by the Joint Chiefs of Staff, these standards are published in the MIL-STD-188 series of documents. The MIL-STD-188 series standards are encompassed by the DoD’s Joint Technical Architecture, for any DoD Agency to get a waiver to receive an item that deviates from the standards they also must apply to the JSC. Currently the DoD is placing its emphasis on the development of standards for tactical. Note, The following list of documents are those that are presently active, documents with three digit numbers followed by a letter of the alphabet indicate that they are revisions of an older version of that document. According to the DoD the MIL-STD-188-100 series contains technical standards and design objectives which are common to both the long haul and tactical communications systems, database with most MILSTD and DEFSTAN publications
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This article incorporates public domain material from the General Services Administration document "Federal Standard 1037C" (in support of MIL-STD-188).
K. Trivedi and A. Bobbio, Reliability and Availability Engineering: Modeling, Analysis and Applications, Cambridge University Press, 2017.