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Devs
DEVS, abbreviating Discrete Event System Specification, is a modular and hierarchical formalism for modeling and analyzing general systems that can be discrete event systems which might be described by state transition tables, and continuous state systems which might be described by differential equations, and hybrid continuous state and discrete event systems. DEVS is a timed event system. History DEVS is a formalism for modeling and analysis of discrete event systems (DESs). The DEVS formalism was invented by Bernard P. Zeigler, who is emeritus professor at the University of Arizona. DEVS was introduced to the public in Zeigler's first book, ''Theory of Modeling and Simulation'' in 1976, while Zeigler was an associate professor at University of Michigan. DEVS can be seen as an extension of the Moore machine formalism,automata were the mathematical models of Dr. Zeigler's Ph.D. thesis which is a finite state automaton where the outputs are determined by the current state alone (a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moore Machine
In the theory of computation, a Moore machine is a finite-state machine whose current output values are determined only by its current state. This is in contrast to a Mealy machine, whose output values are determined both by its current state and by the values of its inputs. Like other finite state machines, in Moore machines, the input typically influences the next state. Thus the input may indirectly influence subsequent outputs, but not the current or immediate output. The Moore machine is named after Edward F. Moore, who presented the concept in a 1956 paper, “ Gedanken-experiments on Sequential Machines.” Formal definition A Moore machine can be defined as a 6-tuple (S, s_0, \Sigma, O, \delta, G) consisting of the following: * A finite set of states S * A start state (also called initial state) s_0 which is an element of S * A finite set called the input alphabet \Sigma * A finite set called the output alphabet O * A transition function \delta : S \times \Sigma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timed Event System
The General System has been described by Zeigler with the standpoints to define (1) the time base, (2) the admissible input segments, (3) the system states, (4) the state trajectory with an admissible input segment, (5) the output for a given state. A Timed Event System defining the state trajectory associated with the current and event segments came from the class of General System to allows non-deterministic behaviors in it. Since the behaviors of DEVS can be described by Timed Event System, DEVS and RTDEVS is a sub-class or an equivalent class of Timed Event System. Timed Event Systems A timed event system is a structure \mathcal= where * \,Z is ''the set of events''; * \,Q is ''the set of states''; * \,Q_0 \subseteq Q is ''the set of initial states''; * Q_A \subseteq Q is ''the set of accepting states''; * \Delta \subseteq Q \times \Omega_ \times Q is ''the set of state trajectories'' in which (q,\omega,q') \in \Delta indicates that a state q \in Q can change int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programmable Logic Controller
A programmable logic controller (PLC) or programmable controller is an industrial computer that has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, machines, robotic devices, or any activity that requires high reliability, ease of programming, and process fault diagnosis. PLCs can range from small modular devices with tens of Input/output, inputs and outputs (I/O), in a housing integral with the processor, to large rack-mounted modular devices with thousands of I/O, and which are often networked to other PLC and SCADA systems. They can be designed for many arrangements of digital and analog I/O, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. PLCs were first developed in the automobile manufacturing industry to provide flexible, rugged and easily programmable controllers to replace hard-wired relay logic systems. Dick Morley, who invented the first PLC, the Modicon 084, for Gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Developer
Software development is the process of designing and Implementation, implementing a software solution to Computer user satisfaction, satisfy a User (computing), user. The process is more encompassing than Computer programming, programming, writing source code, code, in that it includes conceiving the goal, evaluating feasibility, analyzing software requirements, requirements, software design, design, software testing, testing and software release life cycle, release. The process is part of software engineering which also includes management, organizational management, Software project management, project management, configuration management and other aspects. Software development involves many skills and job specializations including software programmer, programming, software test, testing, Technical writing, documentation, graphic design, user support, marketing, and fundraising. Software development involves many software tools, tools including: compiler, integrated develo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Application Software
Application software is any computer program that is intended for end-user use not operating, administering or programming the computer. An application (app, application program, software application) is any program that can be categorized as application software. Common types of applications include word processor, media player and accounting software. The term ''application software'' refers to all applications collectively and can be used to differentiate from system and utility software. Applications may be bundled with the computer and its system software or published separately. Applications may be proprietary or open-source. The short term ''app'' (coined in 1981 or earlier) became popular with the 2008 introduction of the iOS App Store, to refer to applications for mobile devices such as smartphones and tablets. Later, with introduction of the Mac App Store (in 2010) and Windows Store (in 2011), the term was extended in popular use to include desktop a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simulation
A simulation is an imitative representation of a process or system that could exist in the real world. In this broad sense, simulation can often be used interchangeably with model. Sometimes a clear distinction between the two terms is made, in which simulations require the use of models; the model represents the key characteristics or behaviors of the selected system or process, whereas the simulation represents the evolution of the model over time. Another way to distinguish between the terms is to define simulation as experimentation with the help of a model. This definition includes time-independent simulations. Often, computer simulation, computers are used to execute the simulation. Simulation is used in many contexts, such as simulation of technology for performance tuning or optimizing, safety engineering, testing, training, education, and video games. Simulation is also used with scientific modelling of natural systems or human systems to gain insight into their functio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
