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Swiss Cheese Model
The Swiss cheese model of accident causation is a model used in risk analysis and risk management, including aviation safety, engineering, healthcare, emergency service organizations, and as the principle behind layered security, as used in computer security and defense in depth. It likens human systems to multiple slices of Swiss cheese, stacked side by side, in which the risk of a threat becoming a reality is mitigated by the differing layers and types of defenses which are "layered" behind each other. Therefore, in theory, lapses and weaknesses in one defense do not allow a risk to materialize, since other defenses also exist, to prevent a single point of failure. The model was originally formally propounded by James T. Reason of the University of Manchester, and has since gained widespread acceptance. It is sometimes called the "cumulative act effect". Although the Swiss cheese model is respected and considered to be a useful method of relating concepts, it has been subjec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swiss Cheese Model
The Swiss cheese model of accident causation is a model used in risk analysis and risk management, including aviation safety, engineering, healthcare, emergency service organizations, and as the principle behind layered security, as used in computer security and defense in depth. It likens human systems to multiple slices of Swiss cheese, stacked side by side, in which the risk of a threat becoming a reality is mitigated by the differing layers and types of defenses which are "layered" behind each other. Therefore, in theory, lapses and weaknesses in one defense do not allow a risk to materialize, since other defenses also exist, to prevent a single point of failure. The model was originally formally propounded by James T. Reason of the University of Manchester, and has since gained widespread acceptance. It is sometimes called the "cumulative act effect". Although the Swiss cheese model is respected and considered to be a useful method of relating concepts, it has been subjec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bethe Lattice
In statistical mechanics and mathematics, the Bethe lattice (also called a regular tree) is an infinite connected cycle-free graph where all vertices have the same number of neighbors. The Bethe lattice was introduced into the physics literature by Hans Bethe in 1935. In such a graph, each node is connected to ''z'' neighbors; the number ''z'' is called either the coordination number or the degree, depending on the field. Due to its distinctive topological structure, the statistical mechanics of lattice models on this graph are often easier to solve than on other lattices. The solutions are related to the often used Bethe approximation for these systems. Basic Properties When working with the Bethe lattice, it is often convenient to mark a given vertex as the root, to be used as a reference point when considering local properties of the graph. Sizes of Layers Once a vertex is marked as the root, we can group the other vertices into layers based on their distance from the ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redundancy (engineering)
In engineering, redundancy is the intentional duplication of critical components or functions of a system with the goal of increasing reliability of the system, usually in the form of a backup or fail-safe, or to improve actual system performance, such as in the case of GNSS receivers, or multi-threaded computer processing. In many safety-critical systems, such as fly-by-wire and hydraulic systems in aircraft, some parts of the control system may be triplicated, which is formally termed triple modular redundancy (TMR). An error in one component may then be out-voted by the other two. In a triply redundant system, the system has three sub components, all three of which must fail before the system fails. Since each one rarely fails, and the sub components are expected to fail independently, the probability of all three failing is calculated to be extraordinarily small; it is often outweighed by other risk factors, such as human error. Redundancy may also be known by the terms "m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proximate Cause
In law and insurance, a proximate cause is an event sufficiently related to an injury that the courts deem the event to be the cause of that injury. There are two types of causation in the law: cause-in-fact, and proximate (or legal) cause. Cause-in-fact is determined by the "but for" test: But for the action, the result would not have happened.. (For example, but for running the red light, the collision would not have occurred.) The action is a necessary condition, but may not be a sufficient condition, for the resulting injury. A few circumstances exist where the but for test is ineffective (see But-for test). Since but-for causation is very easy to show (but for stopping to tie your shoe, you would not have missed the train and would not have been mugged), a second test is used to determine if an action is close enough to a harm in a "chain of events" to be legally valid. This test is called proximate cause. Proximate cause is a key principle of Insurance and is concerned w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proximate And Ultimate Causation
A proximate cause is an event which is ''closest'' to, or immediately responsible for causing, some observed result. This exists in contrast to a higher-level ultimate cause (or ''distal cause'') which is usually thought of as the "real" reason something occurred. * ''Example:'' Why did the ship sink? ** Proximate cause: Because it was holed beneath the waterline, water entered the hull and the ship became denser than the water which supported it, so it could not stay afloat. ** Ultimate cause: Because the ship hit a rock which tore open the hole in the ship's hull. In most situations, an ultimate cause may itself be a proximate cause in comparison to a further ultimate cause. Hence we can continue the above example as follows: * ''Example:'' Why did the ship hit the rock? ** Proximate cause: Because the ship failed to change course to avoid it. ** Ultimate cause: Because the ship was under autopilot and the autopilot's data was inaccurate. ** (even stronger): Because the ship ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitigation
Mitigation is the reduction of something harmful or the reduction of its harmful effects. It may refer to measures taken to reduce the harmful effects of hazards that remain ''in potentia'', or to manage harmful incidents that have already occurred. It is a stage or component of emergency management and of risk management. The theory of mitigation is a frequently used element in criminal law and is often used by a judge to try cases such as murder, where a perpetrator is subject to varying degrees of responsibility as a result of one's actions. Disaster mitigation An all-hazards approach to disaster management considers all known hazards and their natural and anthropogenic potential risks and impacts, with the intention of ensuring that measures taken to mitigate one type of risk do not increase vulnerability to other types of risks. Proactive disaster mitigation measures are generally more effective than reactive measures in eliminating or reducing the impacts, but not all dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latent Human Error
Latent human error is a term used in safety work and accident prevention, especially in aviation, to describe human errors which are likely to be made due to systems or routines that are formed in such a way that humans are disposed to making these errors. Latent human errors are frequently components in causes of accidents. The error is latent and may not materialize immediately, thus, latent human error does not cause immediate or obvious damage. Discovering latent errors is therefore difficult and requires a systematic approach. Latent human error is often discussed in aviation incident investigation, and contributes to over 70% of the accidents. By gathering data about errors made, then collating, grouping and analyzing them, it can be determined whether a disproportionate amount of similar errors are being made. If this is the case, a contributing factor may be disharmony between the respective systems/routines and human nature or propensities. The routines or systems can the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iteration
Iteration is the repetition of a process in order to generate a (possibly unbounded) sequence of outcomes. Each repetition of the process is a single iteration, and the outcome of each iteration is then the starting point of the next iteration. In mathematics and computer science, iteration (along with the related technique of recursion) is a standard element of algorithms. Mathematics In mathematics, iteration may refer to the process of iterating a function, i.e. applying a function repeatedly, using the output from one iteration as the input to the next. Iteration of apparently simple functions can produce complex behaviors and difficult problems – for examples, see the Collatz conjecture and juggler sequences. Another use of iteration in mathematics is in iterative methods which are used to produce approximate numerical solutions to certain mathematical problems. Newton's method is an example of an iterative method. Manual calculation of a number's square root is a co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Healthcare Error Proliferation Model
The healthcare error proliferation model is an adaptation of James Reason’s Swiss Cheese Model designed to illustrate the complexity inherent in the contemporary healthcare delivery system and the attribution of human error within these systems. The healthcare error proliferation model explains the etiology of error and the sequence of events typically leading to adverse outcomes. This model emphasizes the role organizational and external cultures contribute to error identification, prevention, mitigation, and defense construction. Introduction Healthcare systems are ''complex'' in that they are diverse in both structure (e.g. nursing units, pharmacies, emergency departments, operating rooms) and professional mix (e.g. nurses, physicians, pharmacists, administrators, therapists) and made up of multiple interconnected elements with ''adaptive'' tendencies in that they have the capacity to change and learn from experience. The term ''complex adaptive systems'' (CAS) was coine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chain Of Events (accident Analysis)
In accident analysis, a chain of events (or error chain) consists of the contributing factors leading to an undesired outcome. Aviation In aviation accidents and incidents, these contributing actions typically stem from human factor-related mistakes and pilot error, rather than mechanical failure. A study conducted by Boeing found that 55% of airline accidents between 1959 and 2005 were caused by such human related factors, while only 17% of accidents were caused by mechanical issues with the aircraft. The Tenerife airport disaster, the worst accident in aviation history, is a prime example of an accident in which a chain of events and errors can be identified leading up to the crash. Pilot error, communications problems, fog, and airfield congestion (due to a bomb threat and explosion at another airport) all contributed to this catastrophe. See also *Swiss cheese model The Swiss cheese model of accident causation is a model used in risk analysis and risk management, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crew Resource Management
Crew resource management or cockpit resource management (CRM)Diehl, Alan (2013) "Air Safety Investigators: Using Science to Save Lives-One Crash at a Time." Xlibris Corporation. . http://www.prweb.com/releases/DrAlanDiehl/AirSafetyInvestigators/prweb10735591.htm is a set of training procedures for use in environments where human error can have devastating effects. CRM is primarily used for improving aviation safety and focuses on interpersonal communication, leadership, and decision making in aircraft cockpits. Its founder is David Beaty, a former Royal Air Force and a BOAC pilot who wrote "The Human Factor in Aircraft Accidents" (1969). Despite the considerable development of electronic aids since then, many principles he developed continue to prove effective. CRM in the US formally began with a National Transportation Safety Board (NTSB) recommendation written by NTSB Air Safety Investigator and aviation psychologist Alan Diehl Air Crash Investigation: Focused on Failure"''D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Error
A medical error is a preventable adverse effect of care (" iatrogenesis"), whether or not it is evident or harmful to the patient. This might include an inaccurate or incomplete diagnosis or treatment of a disease, injury, syndrome, behavior, infection, or other ailment. Definitions The word ''error'' in medicine is used as a label for nearly all of the clinical incidents that harm patients. Medical errors are often described as human errors in healthcare. Whether the label is a medical error or human error, one definition used in medicine says that it occurs when a healthcare provider chooses an inappropriate method of care, improperly executes an appropriate method of care, or reads the wrong CT scan. It has been said that the definition should be the subject of more debate. For instance, studies of hand hygiene compliance of physicians in an ICU show that compliance varied from 19% to 85%. The deaths that result from infections caught as a result of treatment providers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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