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Load Shift
Load shifting is a dangerous phenomenon in water, air, and ground transportation where cargo shifts in a cargo vehicle. This causes the vehicle to tilt, which causes even more movement of the cargo, and further tilting, thereby creating a positive feedback loop. If not corrected, this will lead to severe tipping or even capsizing. Such a dangerous occurrence is prevented by active load management, avoiding high sea conditions for ships, and proper shipping container, container/bulkhead (partition), bulkhead design. On a cargo airplane, a professional loadmaster is necessary to prevent load shifting. If cargo is not adequately secured, it can move during flight, and move the center of gravity outside of its safe operating limits, which will cause the aircraft to become uncontrollable or Stall (fluid mechanics), stall, and crash. Ships Ships are used to transport a majority of today's goods which is approximately 90% of all non bulk cargo. Ensuring that loads do not dangerously shi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Positive Feedback
Positive feedback (exacerbating feedback, self-reinforcing feedback) is a process that occurs in a feedback loop where the outcome of a process reinforces the inciting process to build momentum. As such, these forces can exacerbate the effects of a small disturbance. That is, the effects of a perturbation on a system include an increase in the magnitude of the perturbation. That is, ''A produces more of B which in turn produces more of A''.Keesing, R.M. (1981). Cultural anthropology: A contemporary perspective (2nd ed.) p.149. Sydney: Holt, Rinehard & Winston, Inc. In contrast, a system in which the results of a change act to reduce or counteract it has negative feedback. Both concepts play an important role in science and engineering, including biology, chemistry, and cybernetics. Mathematically, positive feedback is defined as a positive loop gain around a closed loop of cause and effect. That is, positive feedback is Phase (waves), in phase with the input, in the sense that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Elsevier
Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell (journal), Cell'', the ScienceDirect collection of electronic journals, ''Trends (journals), Trends'', the ''Current Opinion (Elsevier), Current Opinion'' series, the online citation database Scopus, the SciVal tool for measuring research performance, the ClinicalKey search engine for clinicians, and the ClinicalPath evidence-based cancer care service. Elsevier's products and services include digital tools for Data management platform, data management, instruction, research analytics, and assessment. Elsevier is part of the RELX Group, known until 2015 as Reed Elsevier, a publicly traded company. According to RELX reports, in 2022 Elsevier published more than 600,000 articles annually in over 2,800 journals. As of 2018, its archives contained over 17 million documents and 40,000 Ebook, e-books, with over one b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
1981 Pushkin Tu-104 Crash
On 7 February 1981, a Tupolev Tu-104A passenger jet crashed during take off from Pushkin Airport near Leningrad, Soviet Union, resulting in the death of all 50 people on board, including 28 high-ranking Soviet military personnel. The official investigation concluded that the aircraft was improperly loaded. Accident At 18:00 local time, the Tu-104A lined up on runway 21 and commenced its take-off run during snowing weather conditions. After rotation, the aircraft pitched up beyond normal take-off attitude, and eight seconds after lift off, at an altitude above ground level of , the Tupolev stalled and entered a right bank. The aircraft continued to roll right until it struck the ground from the departure end of the runway, crashing nearly inverted and bursting into flames, killing 49 of the 50 people on board. One person in the cockpit was ejected from the nose A nose is a sensory organ and respiratory structure in vertebrates. It consists of a nasal cavity inside the head ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
National Airlines Flight 102
National Airlines Flight 102 (N8102/NCR102) was a cargo flight operated by National Airlines (N8), National Airlines between Camp Shorabak, Camp Shorabak (formerly Camp Bastion) near the city of Lashkargah in Afghanistan and Al Maktoum Airport in Dubai, with a refueling stop at Bagram Airfield, Afghanistan. On 29 April 2013, the Boeing 747-400 operating the flight crashed within the perimeter of the Bagram Airfield moments after taking off, killing all seven people on board. The subsequent investigation concluded that improperly secured cargo broke free during the take-off and Load shifting, rolled to the back of the cargo hold, crashing through the rear pressure bulkhead and disabling the rear flight control systems. This rendered the aircraft stuck in an uncontrollable pitch-up attitude and induced a stall, and made recovery by the pilots impossible. Accident At the time of the accident, the airline had been operating between Camp Bastion and Dubai for a month. Flight 102 ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
US Department Of Transportation
The United States Department of Transportation (USDOT or DOT) is one of the executive departments of the U.S. federal government. It is headed by the secretary of transportation, who reports directly to the president of the United States and is a member of the president's Cabinet. The department's fiscal year 2022–2026 strategic plan states that its mission is "to deliver the world's leading transportation system, serving the American people and economy through the safe, efficient, sustainable, and equitable movement of people and goods." History In 1965, Najeeb Halaby, was granted authority over aviation and railroads through the commerce clause of the Constitution, the Federal Highway Administration and Federal Transit Administration primarily provided funding for state and local projects, without significant influence over road construction and operation. Halaby emphasized the need for improved coordination and expressed frustration at the lack of an overall plan. "O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Weight Control And Balance Of An Aircraft
In science and engineering, the weight of an object is a quantity associated with the gravitational force exerted on the object by other objects in its environment, although there is some variation and debate as to the exact definition. Some standard textbooks define weight as a vector quantity, the gravitational force acting on the object. Others define weight as a scalar quantity, the magnitude of the gravitational force. Yet others define it as the magnitude of the reaction force exerted on a body by mechanisms that counteract the effects of gravity: the weight is the quantity that is measured by, for example, a spring scale. Thus, in a state of free fall, the weight would be zero. In this sense of weight, terrestrial objects can be weightless: so if one ignores air resistance, one could say the legendary apple falling from the tree, on its way to meet the ground near Isaac Newton, was weightless. The unit of measurement for weight is that of force, which in the International ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
International Maritime Organization
The International Maritime Organization (IMO; ; ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations responsible for regulating maritime transport. The IMO was established following agreement at a UN conference held in Geneva in 1948 and the IMO came into existence ten years later, meeting for the first time on 17 March 1958. Headquartered in London, United Kingdom, the IMO, in 2024, has 176 Member States and three Associate Members. The IMO's primary purpose is to develop and maintain a comprehensive regulatory framework for shipping and its remit today includes maritime safety, environmental concerns, and Admiralty law, legal matters, among other issues. IMO is governed by an assembly of members which meets every two years. Its finance and organization is administered by a council of 40 members elected from the assembly. The work of IMO is conducted through five committees and these are supported by technical subcommittees. Other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
SOLAS Convention
The International Convention for the Safety of Life at Sea (SOLAS) is an international maritime treaty which sets out minimum safety standards in the construction, equipment and operation of merchant ships. The International Maritime Organization convention requires signatory flag states to ensure that ships flagged by them comply with at least these standards. Initially prompted by the sinking of the Titanic, the current version of SOLAS is the 1974 version, known as SOLAS 1974, which came into force on 25 May 1980, and has been amended several times. , SOLAS 1974 has 167 contracting states, which flag about 99% of merchant ships around the world in terms of gross tonnage. SOLAS in its successive forms is generally regarded as the most important of all international treaties concerning the safety of merchant ships. Signatories The non-parties to SOLAS 1974 include numerous landlocked countries, as well as El Salvador, Micronesia and East Timor. Some others including Bolivi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bilge
The bilge of a ship or boat is the part of the hull that would rest on the ground if the vessel were unsupported by water. The "turn of the bilge" is the transition from the bottom of a hull to the sides of a hull. Internally, the bilges (usually used in the plural in this context) is the lowest compartment on a ship or seaplane, on either side of the keel and (in a traditional wooden vessel) between the floors. The first known use of the word is from 1513. Bilge water The word is sometimes also used to describe the water that collects in this area. Water that does not drain off the side of the deck or through a hole in the hull, which it would typically do via a scupper, instead drains down into the ship into the bilge. This water may be from rough seas, rain, leaks in the hull or stuffing box, or other interior spillage. The collected water must be pumped out to prevent the bilge from becoming too full and threatening to sink the ship. Bilge water can be found aboard a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Free Surface Effect
The free surface effect is a mechanism which can cause a watercraft to become unstable and capsize. It refers to the tendency of liquids — and of unbound aggregates of small solid objects, like seeds, gravel, or crushed ore, whose behavior approximates that of liquids — to move in response to changes in the attitude of a craft's cargo holds, decks, or liquid tanks in reaction to operator-induced motions (or sea states caused by waves and wind acting upon the craft). When referring to the free surface effect, the condition of a tank that is not full is described as a "slack tank", while a full tank is "pressed up". Stability and equilibrium In a normally loaded vessel any rolling from perpendicular is countered by a righting moment generated from the increased volume of water displaced by the hull on the lowered side. This assumes the center of gravity of the vessel is relatively constant. If a moving mass inside the vessel moves in the direction of the roll, this counters t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
ScienceDirect
ScienceDirect is a searchable web-based bibliographic database, which provides access to full texts of scientific and medical publications of the Dutch publisher Elsevier as well of several small academic publishers. It hosts over 18 million publications from more than 4,000 academic journals and 30,000 e-books. The access to the full-text requires subscription, while the bibliographic metadata are free to read. ScienceDirect was launched by Elsevier in March 1997. Usage The journals are grouped into four main sections: *''Physical Sciences and Engineering'' *''Life Sciences'' *''Health Sciences'' *''Social Sciences and Humanities''. Article abstracts are freely available, and access to their full texts (in PDF and, for newer publications, also HTML) generally requires a subscription or pay-per-view purchase unless the content is freely available in open access. Papers published under several open access licenses are available on ScienceDirect without cost. Access to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Center Of Mass
In physics, the center of mass of a distribution of mass in space (sometimes referred to as the barycenter or balance point) is the unique point at any given time where the weight function, weighted relative position (vector), position of the distributed mass sums to zero. For a rigid body containing its center of mass, this is the point to which a force may be applied to cause a linear acceleration without an angular acceleration. Calculations in mechanics are often simplified when formulated with respect to the center of mass. It is a hypothetical point where the entire mass of an object may be assumed to be concentrated to visualise its motion. In other words, the center of mass is the particle equivalent of a given object for application of Newton's laws of motion. In the case of a single rigid body, the center of mass is fixed in relation to the body, and if the body has uniform density, it will be located at the centroid. The center of mass may be located outside the Phys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
