Different Kinds Of Dependencies Research Articles

Equation of state for polymer solution

The flow pattern through a cloud of polymer segments is obviously different from the flow pattern around a solid object. It can be shown theoretically, however, that the partial viscosity due to the cloud can take the same value as for a solid sphere with the radius of gyration of the cloud as its radius. The specific viscosity of polymer solution has been derived as 2.5( c/ c I), with c I being the internal concentration associated with a polymer molecule. The internal concentration is the ratio of mass over the volume of gyration of segments in a polymer chain. A radius of gyration exists for any type of polymers, flexible or rigid, exhibiting different kinds of dependence on the molecular weight. From the expression of the specific viscosity, the intrinsic viscosity is shown to be equal to 2.5/ c ∗, c ∗ being the (minimum) internal concentration for the state of maximum conformational entropy. The equation for the specific viscosity, thus obtained, is expanded into a polynomial in c[ η]. This formula is shown to agree with data for several kinds of polymers, with flexible, semi-rigid and rigid. The quantity 1/ c I can be interpreted as an expression for the chain stiffness. In polyelectrolytes, coulombic repulsive potentials affect the chain stiffness. The dependence of c I on the effective population of polyions in the polyelectrolyte molecule is discussed. An equation of state for the polymer solution is formulated that included the internal concentration. The virial coefficients emerge as a result of c I not always being equal to c ∗, and they are molecular weight dependent.

Artificial Neural Networks for the Identification of the Differences between “Light” and “Heavy” Alcoholics, Starting from Five Nonlinear Biological Variables

This article makes a comparison among three types of evaluation systems based on a set of data composed of “heavy” alcoholics and “light” alcoholics. The three systems are: 1) a system based on genetic algorithms called BEAGLE; b) seven different types of Artificial Neural Networks; c) a metasystem called MetaNet. The technical aim was to compare the classification capability of these three systems in terms of two classes (“heavy” alcoholics and “light” alcoholics). From the results obtained, the MetaNet system stand out. Globally, it has the best result, followed by the two Artificial Neural Networks, Squash and Logicon Projection. The results obtained prove that the advanced elaboration data systems applied in the social and health fields can be employed in prevention programs having an aim to reduce the social impact of certain pathologies correlated with different kinds of dependence.

Externalities — A market model failure

We focus here on a set of conceptual problems related to the accepted theory of externalities. We are primarily concerned with difficulties that arise when a theoretical system is extended beyond its logical domain. This is the practice in externality theory when the market model assuming independent agents is used to analyze physical interdependency. The different kinds of dependencies obscure the standard use of the Paretian analysis, as the issues of rights and efficiency are mixed up. The creation of emissions and the creation of externalities are further not held apart producing flows in the efficiency evaluations. Due to the interdependencies involved, actions of both emitter and victim must be taken into account while searching for efficient policies. Finally, we analyze the interrelationships between what is termed the internal structure of the market model and the annexed sphere of externalities. We conclude that the accepted policy prescriptions both assume and demand no interrelationships between these two spheres. We find the assumption unrealistic and inconsistent as concerns the basic foundations of the market model. There are two main traditions addressing externalities — the Coasean and the Pigovian. This paper shows that both are vulnerable to the above critique. Thus the presumption that externality theory is now settled and coherent is seen to be without theoretical support.

Applying object-oriented analysis on a case study

This paper aims at showing that some object-oriented fundamental principles provide new suitable mechanisms for the analysis and the specification of complex systems. Three principles are presented and discussed in this paper through a case study. The locality principle allows to concentrate on one object, stressing its structure and behaviour through the notion of life cycle, the refinement principle allows to refine objects by means of inheritance links, the globality principle allows to enlighten on different kinds of dependencies amongst objects. The case study is developed with the model of the Modway method. The Modway method is an object-oriented method which makes use of object concepts since the very beginning of the development process.

The interdisciplinary study of coordination

This survey characterizes an emerging research area, sometimes called coordination theory , that focuses on the interdisciplinary study of coordination. Research in this area uses and extends ideas about coordination from disciplines such as computer science, organization theory, operations research, economics, linguistics, and psychology. A key insight of the framework presented here is that coordination can be seen as the process of managing dependencies among activities. Further progress, therefore, should be possible by characterizing different kinds of dependencies and identifying the coordination processes that can be used to manage them. A variety of processes are analyzed from this perspective, and commonalities across disciplines are identified. Processes analyzed include those for managing shared resources, producer/consumer relationships, simultaneity constraints , and task/subtask dependencies . Section 3 summarizes ways of applying a coordination perspective in three different domains:(1) understanding the effects of information technology on human organizations and markets, (2) designing cooperative work tools, and (3) designing distributed and parallel computer systems. In the final section, elements of a research agenda in this new area are briefly outlined.

Testing the food-first hypothesis: A cross-national study of dependency, sectoral growth and food intake in less developed countries

Previous cross-national studies on dependency and economic growth in less developed countries (LDCs) seldom compare the impacts of different kinds of dependency. Their focus on economic growth also overlooks the fact that growth, per se, does not necessarily benefit the masses. An alternative measure of the absolute living standard of the masses, i.e., food intake, is examined in this paper. This study analyzes data from 73 LDCs. After comparing the effects of manufacturing growth and cereal production growth on food intake, this study supports the food-first hypothesis derived from Lappé and Collins' (1977) work, since it demonstrates that in most LDCs, even in middle-income LDCs, cereal production has a much stronger effect on food intake than does manufacturing growth.