There is a long history of work attempting to build good ontologies for a variety of task domains, including early work on an ontology for liquids, the lumped element model widely used in representing electronic circuits ( e. g .,), as well as ontologies for time, belief, and even programming itself.

Consider the difference that arises in selecting the lumped element view of a circuit rather than the electrodynamic view of the same device.

These ideal electrical elements represent real, physical electrical or electronic components but they do not exist physically and they are assumed to have ideal properties according to a lumped element model, while components are objects with less than ideal properties, a degree of uncertainty in their values and some degree of nonlinearity, each of which may require a combination of multiple electrical elements in order to approximate its function.

The lumped element model ( also called lumped parameter model, or lumped component model ) simplifies the description of the behaviour of spatially distributed physical systems into a topology consisting of discrete entities that approximate the behaviour of the distributed system under certain assumptions.

The lumped element model of electronic circuits makes the simplifying assumption that the attributes of the circuit, resistance, capacitance, inductance, and gain, are concentrated into idealized electrical components ; resistors, capacitors, and inductors, etc.

The lumped element model is valid whenever, where denotes the circuit's characteristic length, and denotes the circuit's operating wavelength.

Another way of viewing the validity of the lumped element model is to note that this model ignores the finite time it takes signals to propagate around a circuit.

Whenever this propagation time is not significant to the application the lumped element model can be used.

The exact point at which the lumped element model can no longer be used depends to a certain extent on how accurately the signal needs to be known in a given application.

This is in contrast to the more common lumped element model, which assumes that these values are lumped into electrical components that are joined by perfectly conducting wires.

Unlike the lumped element model, it assumes non-uniform current along each branch and non-uniform voltage along each node.

The distributed element model is more accurate but more complex than the lumped element model.

The use of infinitesimals will often require the application of calculus whereas circuits analysed by the lumped element model can be solved with linear algebra.

Where reflections are present on the line, quite short lengths of line can exhibit effects that are simply not predicted by the lumped element model.

The analysis of charge carriers crossing the base region is not accurate when the base region is simply treated as a lumped element.

The most common approach is to roll up all the distributed capacitance into one lumped element in parallel with the inductance and resistance of the coil.

The Smith chart may also be used for lumped element matching and analysis problems.

One way to deal with these inherent resistances in circuit analysis is to use a lumped element model to express each physical component as a combination of an ideal component and a small resistor in series, the ESR.

In a capacitor made of a dielectric placed between conductors, the typical lumped element model includes a lossless ideal capacitor in series with a resistor termed the equivalent series resistance ( ESR ) as shown below.

A real capacitor has a lumped element model of a lossless ideal capacitor in series with an equivalent series resistance ( ESR ).

The Debye model and the Lorentz model use a 1st-order and 2nd-order ( respectively ) lumped system parameter linear representation ( such as an RC and an LRC resonant circuit ).

In this case, the region with high conductivity can often be treated in the lumped capacitance model, as a " lump " of material with a simple thermal capacitance consisting of its aggregate heat capacity.

For example, a Biot number less than 0. 1 typically indicates less than 5 % error will be present when assuming a lumped-capacitance model of transient heat transfer ( also called lumped system analysis ).

System analysis by the lumped capacitance model is a common approximation in transient conduction that may be used whenever heat conduction within an object is much faster than heat conduction across the boundary of the object.

Since it is not easy to produce an electromagnetic expression for the railgun force that is both simple and reasonably accurate, most simple railgun analyses actually used a lumped circuit model to describe the relationship between the driving current and the railgun force.

Representation of a lumped model made up of a voltage source and a resistor.

Buses and jeepneys are lumped together and called " public utility vehicles " or PUVs, or separated referred to as PUB for " public utility bus " and PUJ for " public utility jeepney ".

Filmmaker Oliver Stone, however, has accused the film of promoting " the worship of World War II as the good war ," and has lumped it alongside films such as Gladiator and Black Hawk Down that he believes were well-made, but may have inadvertently contributed to Americans ' readiness for the 2003 invasion of Iraq.

" Fellow White House Counsel Bernard Nussbaum felt that if Foster had lived, he would have helped resist the calls to appoint Independent Counsels, and the many investigations lumped under the Whitewater umbrella that occupied the administration and the Clintons for the rest of their terms, might not have happened.

Le Pen criticizes the other political parties as the " establishment " and lumped all major parties ( Communist, Socialist, Union for French Democracy ( UDF ) and Rally for the Republic ( RPR )) into the " Gang of Four " ( la bande des quatre – an allusion to the Gang of Four during China's Cultural Revolution ).

The unrelated categories of optical doubles and true binaries are lumped together for historical and practical reasons.

An LTI system is completely specified by its transfer function ( which is a rational function for digital and lumped analog LTI systems ).

Buytenwegh de Leyens, Meerzicht, Oosterheem and Rokkeveen have a wijkpost each, while Noordhove and Seghwaert share a common station and Wijkpost Center serves Dorp, Driemanspolder, Palendstein and Stadscentrum, which are for some purposes also lumped together as " Zoetermeer Centrum ".

“ In considering the Tanana River as a whole, however, the Crossing and Upper Tanana natives should be lumped together, for between the Crossing and Healy River occur a whole series of rapids which today make navigation exceedingly dangerous and in earlier days practically prevented it .” ( 23 )

While commonly lumped together with Delta Blues singers, McDowell actually may be considered the first of the bluesmen from the ' North Mississippi ' region-parallel to, but somewhat east of the Delta region-to achieve widespread recognition for his work.

The family's closest relatives have for a long time assumed to be the other suboscine birds, and particularly the Old World broadbills and asities ( formerly treated as two families, now either lumped into one or split into four ).

To account for leakage in capacitors for example, we can model the non-ideal capacitor as having a large lumped resistor connected in-parallel even though the leakage is, in reality distributed throughout the dielectric.

* IMTEK Mathematica Supplement ( IMS ), the Open Source IMTEK Mathematica Supplement ( IMS ) for lumped modelling

This lumped model works successfully at low frequencies but falls apart at high frequencies where the usual practice is to simply measure ( or specify ) an overall Q for the inductor without associating a specific equivalent circuit.

Although it is physically the same as the late-time ISW, for observational purposes it is usually lumped in with the primordial CMB, since the matter fluctuations that cause it are in practice undetectable.

Meanwhile, the Old World E. caeruleus is again called Black-winged Kite, while the name Black-shouldered Kite is now reserved for an Australian species, Elanus axillaris, which had also been lumped into E. caeruleus but now regarded as separate again.

Gerbner is also criticized for the fact that he " lumped together " all forms of violence ; he did not split up the different types of television programs.