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Nuclear terrorism

Nuclear terrorism refers to any person or persons who detonate a nuclear weapon as an act of terrorism (meaning illegal or immoral use of violence for a political or religious cause). Some definitions of nuclear terrorism include the sabotage of a nuclear facility and/or the detonation of a radiological device, colloquially termed a dirty bomb, but consensus is lacking. In legal terms, nuclear terrorism is an offense committed if a person unlawfully and intentionally "uses in any way radioactive material … with the intent to cause death or serious bodily injury; or with the intent to cause substantial damage to property or to the environment; or with the intent to compel a natural or legal person, an international organization or a State to do or refrain from doing an act", according to the 2005 United Nations International Convention for the Suppression of Acts of Nuclear Terrorism. The possibility of terrorist organizations using nuclear weapons (including those of a smal

Scope

Nuclear terrorism could include: Acquiring or fabricating a nuclear weapon Fabricating a dirty bomb Attacking a nuclear reactor, e.g., by disrupting critical inputs (e.g. water supply) Attacking or taking over a nuclear-armed submarine, plane, or base. Nuclear terrorism, according to a 2011 report published by the Belfer Center for Science and International Affairs at Harvard University, can be executed and distinguished via four pathways: The use of a nuclear weapon that has been stolen or purchased on the black market The use of a crude explosive device built by terrorists or by nuclear scientists who the terrorist organization has furtively recruited The use of an explosive device constructed by terrorists and their accomplices using their own fissile material The acquisition of fissile material from a nation-state. The creation of a device that may give information about the configuration of components needed for a nuclear weapon Former U.S. President Barack Obama called nuc

History

As early as December 1945, politicians worried about the possibility of smuggling nuclear weapons into the United States, though this was still in the context of a battle between the superpowers of the Cold War. Congressmen quizzed the "father of the atomic bomb," J. Robert Oppenheimer, about the possibility of detecting a smuggled atomic bomb: Sen. Millikin: We... have mine-detecting devices, which are rather effective... I was wondering if anything of that kind might be available to use as a defense against that particular type of use of atomic bombs. Dr. Oppenheimer: If you hired me to walk through the cellars of Washington to see whether there were atomic bombs, I think my most important tool would be a screwdriver to open the crates and look. I think that just walking by, swinging a little gadget would not give me the information. This sparked further work on the question of smuggled atomic devices during the 1950s. Discussions of non-state nuclear terrorism among expe

Militant groups

Nuclear weapons materials on the black market are a global concern, and there is concern about the possible detonation of a small, crude nuclear weapon by a militant group in a major city, with significant loss of life and property. It is feared that a terrorist group could detonate a dirty bomb, a type of radiological weapon. A dirty bomb is made of any radioactive source and a conventional explosive. There would be no nuclear blast and likely no fatalities, but the radioactive material is dispersed and can cause extensive fallout depending on the material used. There are other radiological weapons called radiological exposure devices where an explosive is not necessary. A radiological weapon may be very appealing to terrorist groups as it is highly successful in instilling fear and panic among a population (particularly because of the threat of radiation poisoning) and would contaminate the immediate area for some period of time, disrupting attempts to repair the damage and subseque

Incidents involving nuclear material

Information reported to the International Atomic Energy Agency (IAEA) shows "a persistent problem with the illicit trafficking in nuclear and other radioactive materials, thefts, losses and other unauthorized activities". The IAEA Illicit Nuclear Trafficking Database notes 1,266 incidents reported by 99 countries over the last 12 years, including 18 incidents involving HEU or plutonium trafficking: There have been 18 incidents of theft or loss of highly enriched uranium (HEU) and plutonium confirmed by the IAEA. British academic Shaun Gregory alleged in 2009 that terrorists had attacked Pakistani nuclear facilities three times; twice in 2007 and once in 2008. However, the then Director General ISPR Athar Abbas said the claims were "factually incorrect", adding that the sites were "military facilities, not nuclear installations". In November 2007, burglars with unknown intentions infiltrated the Pelindaba nuclear research facility near Pretoria, South Afr

Pakistan

In 2009, a paper published in West Point Military Academy's journal alleged that Pakistan's nuclear sites had been attacked by al-Qaeda and the Taliban at least three times. However, the Pakistan Armed Forces rejected the allegations. Talat Masood, a political analyst, said that the nuclear link was "absolute nonsense". All three attacks were suicide and appeared to aim at causing maximum damage and not seizing weapons. In January 2010, it was revealed that the US army was training a specialised unit "to seal off and snatch back" Pakistani nuclear weapons in the event that militants would obtain a nuclear device or materials that could make one. Pakistan supposedly possesses about 80 nuclear warheads. US officials refused to speak on the record about the American safety plans. A study by the Belfer Center for Science and International Affairs at Harvard University titled "Securing the Bomb 2010," found that Pakistan's stockpile "faces a gr

United States

While in office, President Barack Obama reviewed Homeland Security policy and concluded that "attacks using improvised nuclear devices ... pose a serious and increasing national security risk". In their presidential contest, President George W. Bush and Senator John Kerry both agreed that the most serious danger facing the United States is the possibility that terrorists could obtain a nuclear bomb. Most nuclear-weapon analysts agree that "building such a device would pose few technological challenges to reasonably competent terrorists". The main barrier is acquiring highly enriched uranium. In 2004, Graham Allison, U.S. Assistant Secretary of Defense during the Clinton administration, wrote that “on the current path, a nuclear terrorist attack on America in the decade ahead is more likely than not". In 2004, Bruce Blair, president of the Center for Defense Information stated: "I wouldn't be at all surprised if nuclear weapons are used over the next 15

Policy landscape

Recovery edit The Cooperative Threat Reduction Program (CTR), which is also known as the Nunn–Lugar Cooperative Threat Reduction, is a 1992 law sponsored by Senators Sam Nunn and Richard Lugar. The CTR established a program that gave the U.S. Department of Defense a direct stake in securing loose fissile material inside the since-dissolved Soviet Union. According to Graham Allison, director of Harvard University's Belfer Center for Science and International Affairs, this law is a major reason why not a single nuclear weapon has been discovered outside the control of Russia's nuclear custodians. The Belfer Center is itself running the Project on Managing the Atom, Matthew Bunn is a co-principal investigator of the project, Martin B. Malin is its executive director (circa. 2014). In August 2002, the United States launched a program to track and secure enriched uranium from 24 Soviet-style reactors in 16 countries, in order to reduce the risk of the materials falling into the h

Media coverage

In 2011, the British news agency, The Telegraph , received leaked documents regarding the Guantanamo Bay interrogations of Khalid Sheikh Mohammed. The documents cited Khalid saying that, if Osama bin Laden is captured or killed by the Coalition of the Willing, an al-Qaeda sleeper cell will detonate a "weapon of mass destruction" in a "secret location" in Europe, and promised it would be "a nuclear hellstorm". No such attack occurred after the killing of Osama bin Laden in 2011.

References

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Commodity

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In economics, a commodity is an economic good that has full or substantial fungibility: that is, the market treats instances of the good as equivalent or nearly so with no regard to who produced them. The price of a commodity good is typically determined as a function of its market as a whole: well-established physical commodities have actively traded spot and derivative markets. The wide availability of commodities typically leads to smaller profit margins and diminishes the importance of factors (such as brand name) other than price. Most commodities are raw materials, basic resources, agricultural, or mining products, such as iron ore, sugar, or grains like rice and wheat. Commodities can also be mass-produced unspecialized products such as chemicals and computer memory.

Etymology

The word commodity came into use in English in the 15th century, from the French commodité , "amenity, convenience". Going further back, the French word derives from the Latin commoditas , meaning "suitability, convenience, advantage". The Latin word commodus (from which English gets other words including commodious and accommodate ) meant variously "appropriate", "proper measure, time, or condition", and "advantage, benefit".

Description

Characteristics edit In economics, the term commodity is used specifically for economic goods that have full or partial but substantial fungibility; that is, the market treats their instances as equivalent or nearly so with no regard to who produced them. Karl Marx described this property as follows: "From the taste of wheat, it is not possible to tell who produced it, a Russian serf, a French peasant or an English capitalist." Petroleum and copper are examples of commodity goods: their supply and demand are a part of one universal market. Non-commodity items such as stereo systems have many aspects of product differentiation, such as the brand, the user interface and the perceived quality. The demand for one type of stereo may be much larger than demand for another. The price of a commodity good is typically determined as a function of its market as a whole. Well-established physical commodities have actively traded spot and derivative markets. Hard and soft commodities edi

Commoditization

Commoditization occurs as a goods or services market loses differentiation across its supply base, often by the diffusion of the intellectual capital necessary to acquire or produce it efficiently. As such, goods that formerly carried premium margins for market participants have become commodities, such as generic pharmaceuticals and DRAM chips. An article in The New York Times cites multivitamin supplements as an example of commoditization; a 50 mg tablet of calcium is of equal value to a consumer no matter what company produces and markets it, and as such, multivitamins are now sold in bulk and are available at any supermarket with little brand differentiation. Following this trend, nanomaterials are emerging from carrying premium profit margins for market participants to a status of commodification. There is a spectrum of commoditization, rather than a binary distinction of "commodity versus differentiable product". Few products have complete undifferentiability and hence

Global commodities trading company

This is a list of companies trading globally in commodities, descending by size as of October 28, 2011. Vitol Glencore International AG Trafigura Cargill Salam Investment Archer Daniels Midland Gunvor (company) Mercuria Energy Group Noble Group Louis Dreyfus Group Bunge Limited Wilmar International Olam International

Commodity trade

In the original and simplified sense, commodities were things of value, of uniform quality, that were produced in large quantities by many different producers; the items from each different producer were considered equivalent. On a commodity exchange, it is the underlying standard stated in the contract that defines the commodity, not any quality inherent in a specific producer's product. Commodities exchanges include: Bourse Africa (formerly GBOT) Bursa Malaysia Derivatives (MDEX) Chicago Board of Trade (CBOT) Chicago Mercantile Exchange (CME) Dalian Commodity Exchange (DCE) Euronext.liffe (LIFFE) Kansas City Board of Trade (KCBT) London Metal Exchange (LME) Marché à Terme International de France (MATIF) Mercantile Exchange Nepal Limited (MEX) Multi Commodity Exchange (MCX) National Commodity and Derivatives Exchange (NCDEX) National Commodity Exchange Limited (NCEL) New York Mercantile Exchange (NYMEX) Markets for trading commodities can be very efficient, particula

Inventory data

The inventory of commodities, with low inventories typically leading to more volatile future prices and increasing the risk of a "stockout" (inventory exhaustion). According to economist theorists, companies receive a convenience yield by holding inventories of certain commodities. Data on inventories of commodities are not available from one common source, although data is available from various sources. Inventory data on 31 commodities was used in a 2006 study on the relationship between inventories and commodity futures risk premiums.

Commodification of labor

In classical political economy and especially in Karl Marx's critique of political economy, a commodity is an object or a good or service ("product" or "activity") produced by human labour. Objects are external to man. However, some objects attain "use value" to persons in this world, when they are found to be "necessary, useful or pleasant in life". "Use value" makes an object "an object of human wants", or "a means of subsistence in the widest sense". As society developed, people found that they could trade goods and services for other goods and services. At this stage, these goods and services became "commodities". According to Marx, commodities are defined as objects which are offered for sale or are "exchanged in a market". In the marketplace, where commodities are sold, "use value" is not helpful in facilitating the sale of commodities. Accordingly, in addition to having use va

United Nations Sustainable Development Group

The United Nations Sustainable Development Group ( UNSDG ), previously the United Nations Development Group (UNDG), is a consortium of 36 United Nations funds, programs, specialized agencies, departments and offices that play a role in development. It was created by the Secretary-General of the United Nations in order to improve the effectiveness of United Nations development activities at the country level. Its strategic priorities are to respond to the Triennial comprehensive policy review (TCPR) – which became in 2008 the Quadrennial comprehensive policy review (QCPR) – and global development priorities, as well as to ensure the UN development system becomes more internally focused and coherent. The UNSDG strategic priorities give direction to UNDG members' efforts at the global, regional and country level to facilitate a step change in the quality and impact of UN support at the country level. Currently, the UNSDG is one of the main UN actors involved in the development of the

History

By 1997, there were calls within the United Nations to draw all UN agencies working on development issues together; for the many UN Development Programmes, Funds, and Specialised Agencies were encroaching upon each other's activities. This was especially so with the Delivering as One initiative. An initial proposal was to merge UNICEF, the World Food Programme and the UNFPA into the UNDP. Finally, then Secretary-General Kofi Annan worked to form the UNDG and won praise from then UNDP Administrator James Speth. citation needed In May 2018 the United Nations Development Group (UNDG) was reorganized into the United Nations Sustainable Development Group (UNSDG) in order to accelerate progress toward the Sustainable Development Goals.

Members

The following are all members of the UNSDG, as of March 2019: Food and Agriculture Organization (FAO) International Fund for Agricultural Development (IFAD) International Labour Organization (ILO) International Organization for Migration (IOM) International Trade Centre (ITC) International Telecommunications Union (ITU) Office of the High Commissioner for Human Rights (OHCHR) Joint United Nations Programme on HIV/AIDS (UNAIDS) United Nations Conference on Trade and Development (UNCTAD) United Nations Department of Economic and Social Affairs (UN DESA) United Nations Development Programme (UNDP) / United Nations Capital Development Fund (UNCDF) / United Nations Volunteers (UNV) United Nations Department of Political Affairs (UN DPA) United Nations Economic Commission for Africa (UN ECA) United Nations Economic Commission for Europe United Nations Economic Commission for Latin America and the Caribbean (UN ECLAC) United Nations Environment Programme (UNEP) United Nations

Leadership and organization

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Structure edit The UNSDG is one of the three pillars of the UN system Chief Executives Board (CEB), which furthers coordination and cooperation on a wide range of substantive and management issues facing UN system organizations. The CEB brings the executive heads of UN organizations together on a regular basis under the chairmanship of the Secretary-General. Within the CEB structure, the High-Level Committee on Management works on system-wide administrative and management issues, the High-Level Committee on Programmes considers global policy issues, while the United Nations Development Group deals with operational activities for development with a focus on country-level work. The Administrator of the UN Development Programme (UNDP) chairs the UNSDG. The UNSDG Chair reports to the Secretary-General and the CEB on progress in implementing the group’s work plan, and on the management of the Resident Coordinator System. Leadership edit The United Nations Economic and Social Council and the

Electronics

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Electronics comprises the physics, engineering, technology and applications that deal with the emission, flow and control of electrons in vacuum and matter. It uses active devices to control electron flow by amplification and rectification, which distinguishes it from classical electrical engineering which uses passive effects such as resistance, capacitance and inductance to control current flow. Electronics has had a major effect on the development of modern society. The identification of the electron in 1897, along with the subsequent invention of the vacuum tube which could amplify and rectify small electrical signals, inaugurated the field of electronics and the electron age. This distinction started around 1906 with the invention by Lee De Forest of the triode, which made electrical amplification of weak radio signals and audio signals possible with a non-mechanical device. Until 1950, this field was called "radio technology" because its principal application was th

Branches of electronics

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Electronics has branches as follows: Digital electronics Analogue electronics Microelectronics Circuit design Integrated circuits Power electronics Optoelectronics Semiconductor devices Embedded systems Audio electronics Telecommunications Nanoelectronics Bioelectronics

Electronic devices and components

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An electronic component is any physical entity in an electronic system used to affect the electrons or their associated fields in a manner consistent with the intended function of the electronic system. Components are generally intended to be connected together, usually by being soldered to a printed circuit board (PCB), to create an electronic circuit with a particular function (for example an amplifier, radio receiver, or oscillator). Components may be packaged singly, or in more complex groups as integrated circuits. Some common electronic components are capacitors, inductors, resistors, diodes, transistors, etc. Components are often categorized as active (e.g. transistors and thyristors) or passive (e.g. resistors, diodes, inductors and capacitors).

History of electronic components

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Vacuum tubes (Thermionic valves) were among the earliest electronic components. They were almost solely responsible for the electronics revolution of the first half of the twentieth century. They allowed for vastly more complicated systems and gave us radio, television, phonographs, radar, long-distance telephony and much more. They played a leading role in the field of microwave and high power transmission as well as television receivers until the middle of the 1980s. Since that time, solid-state devices have all but completely taken over. Vacuum tubes are still used in some specialist applications such as high power RF amplifiers, cathode ray tubes, specialist audio equipment, guitar amplifiers and some microwave devices. The first working point-contact transistor was invented by John Bardeen and Walter Houser Brattain at Bell Labs in 1947. In April 1955, the IBM 608 was the first IBM product to use transistor circuits without any vacuum tubes and is believed to be the first all-

Types of circuits

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Circuits and components can be divided into two groups: analog and digital. A particular device may consist of circuitry that has one or the other or a mix of the two types. An important electronic technique in both analog and digital electronics involves the use of feedback. Among many other things this allows very linear amplifiers to be made with high gain, and digital circuits such as registers, computers and oscillators. Analog circuits edit Most analog electronic appliances, such as radio receivers, are constructed from combinations of a few types of basic circuits. Analog circuits use a continuous range of voltage or current as opposed to discrete levels as in digital circuits. The number of different analog circuits so far devised is huge, especially because a 'circuit' can be defined as anything from a single component, to systems containing thousands of components. Analog circuits are sometimes called linear circuits although many non-linear effects are used in analog

Heat dissipation and thermal management

Heat generated by electronic circuitry must be dissipated to prevent immediate failure and improve long term reliability. Heat dissipation is mostly achieved by passive conduction/convection. Means to achieve greater dissipation include heat sinks and fans for air cooling, and other forms of computer cooling such as water cooling. These techniques use convection, conduction, and radiation of heat energy.

Noise

Electronic noise is defined as unwanted disturbances superposed on a useful signal that tend to obscure its information content. Noise is not the same as signal distortion caused by a circuit. Noise is associated with all electronic circuits. Noise may be electromagnetically or thermally generated, which can be decreased by lowering the operating temperature of the circuit. Other types of noise, such as shot noise cannot be removed as they are due to limitations in physical properties.

Electronics theory

Mathematical methods are integral to the study of electronics. To become proficient in electronics it is also necessary to become proficient in the mathematics of circuit analysis. Circuit analysis is the study of methods of solving generally linear systems for unknown variables such as the voltage at a certain node or the current through a certain branch of a network. A common analytical tool for this is the SPICE circuit simulator. Also important to electronics is the study and understanding of electromagnetic field theory.

Electronics lab

Due to the complex nature of electronics theory, laboratory experimentation is an important part of the development of electronic devices. These experiments are used to test or verify the engineer's design and detect errors. Historically, electronics labs have consisted of electronics devices and equipment located in a physical space, although in more recent years the trend has been towards electronics lab simulation software, such as CircuitLogix, Multisim, and PSpice.

Computer aided design (CAD)

Today's electronics engineers have the ability to design circuits using premanufactured building blocks such as power supplies, semiconductors (i.e. semiconductor devices, such as transistors), and integrated circuits. Electronic design automation software programs include schematic capture programs and printed circuit board design programs. Popular names in the EDA software world are NI Multisim, Cadence (ORCAD), EAGLE PCB and Schematic, Mentor (PADS PCB and LOGIC Schematic), Altium (Protel), LabCentre Electronics (Proteus), gEDA, KiCad and many others.

Packaging methods

Many different methods of connecting components have been used over the years. For instance, early electronics often used point to point wiring with components attached to wooden breadboards to construct circuits. Cordwood construction and wire wrap were other methods used. Most modern day electronics now use printed circuit boards made of materials such as FR4, or the cheaper (and less hard-wearing) Synthetic Resin Bonded Paper (SRBP, also known as Paxoline/Paxolin (trade marks) and FR2) – characterised by its brown colour. Health and environmental concerns associated with electronics assembly have gained increased attention in recent years, especially for products destined to the European Union, with its Restriction of Hazardous Substances Directive (RoHS) and Waste Electrical and Electronic Equipment Directive (WEEE), which went into force in July 2006.

Electronic systems design

Electronic systems design deals with the multi-disciplinary design issues of complex electronic devices and systems, such as mobile phones and computers. The subject covers a broad spectrum, from the design and development of an electronic system (new product development) to assuring its proper function, service life and disposal. Electronic systems design is therefore the process of defining and developing complex electronic devices to satisfy specified requirements of the user.

Mounting Options

Electrical components are generally mounted in the following ways: Through-hole (sometimes referred to as 'Pin-Through-Hole') Surface Mount Chassis Mount LGA/BGA/PGA Socket

Electronics industry

The electronics industry consists of various sectors. The central driving force behind the entire electronics industry is the semiconductor industry sector, which has annual sales of over $481 billion as of 2018. The largest industry sector is e-commerce, which generated over $29 trillion in 2017. The most widely manufactured electronic device is the metal-oxide-semiconductor field-effect transistor (MOSFET), with an estimated 13   sextillion MOSFETs having been manufactured between 1960 and 2018.

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