Heterogeneous System

Also found in: Dictionary, Thesaurus, Medical.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Heterogeneous System


a nonuniform physicochemical system comprising parts (phases) that differ in physical properties or chemical composition.

One phase of a heterogeneous system is separated from an adjacent phase by an interface where one or more properties of the system (for example, composition, density, crystal lattice parameters, and electrical or magnetic field) change abruptly. The differences in properties of the individual phases of a heterogeneous system make possible, at least theoretically, their mechanical separation. Examples of heterogeneous systems are water and the water vapor above it (difference in the state of aggregation), a mixture of two different crystalline variants of sulfur (rhombic and monoclinic), and two immiscible liquids, such as oil and water (difference in composition). It is often impossible to draw a sharp line between a heterogeneous system and a homogeneous (uniform) one. Thus the so-called colloidal solutions, where the particles of dissolved substance are so small that the concept of phase cannot be applied to them, form an intermediate range between mechanical mixtures (suspensions) and true (molecular) solutions. The term “heterogeneous system” is widely used in physics and chemistry, especially in chemical thermodynamics.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Applying a nonisothermal treatment by differential scanning calorimetry would reduce the analysis period from months or years to a few days and reduce the problems related to the evaluation of heterogeneous systems.
Caption: Figure 13: Comparison of path loss simulation time between CPU based and heterogeneous system based simulations.
Therefore, the overhead of data preparation is a major factor which we should not be neglected in heterogeneous system. Traditional Amdahl's Law ignores those overheads, so for tasks of high synchronization, parallel execution may result in significantly lower speedup than as predicted by traditional Amdahl's Law.
Weighed combination of both resistivities in the heterogeneous system yield the data given in Table 2.
The parameter for the amounts of computing power available at each node in a heterogeneous system and its heterogeneous level value is given in the 5th paragraph of Section 6 and Table 1.
P Agrawal, "A scalable task duplication based scheduling algorithm for heterogeneous systems," in Proceedings of the 14th International Parallel and Distributed Processing Symposium, pp.
There are only two CRO-based algorithms [27, 30] for DAG scheduling on heterogeneous system so far according to our knowledge.
We consider a heterogeneous system model of multi-users accessing to the unauthorized spectrum in CRN shown in Fig.
The Enterprise application integration environment, which is platform-free, improves the interoperability of heterogeneous systems and provides an open and unified environment; it is realized by message processing mechanisms, interoperability in distributed environments, software combination technologies, heterogeneous system integrations and application middleware specifications.
He first provides an historical account of the development of the modern Saudi bureaucracy from the 1950s through the 1970s, arguing that the bureaucratic system should be characterized as "segmented clientelism"--a heterogeneous system of formal and informal, rent-based clientelism in which vertical links dominate.
An open, heterogeneous system is the only answer," it said.

Full browser ?