Influence of rate of resource flow on dynamics of community of people and artificial beings

We develop and analyze a population model allowing us to examine a system, where people coexist with artificial beings (robots) and the both consume the same resource entering the system. The robot population consists of friendly and aggressive robots that differ in their attitudes towards people. We propose a system of differential equations, which define a dynamics of the populations of people, friendly robots and aggressive robots, and discuss different scenarios of the system evolution including those that lead to disappearance of the human population. We determine conditions that ensure a more or less prosperous future for humanity. We analyze the behavior of the system for different time dependences of the rate of the resource flow (a constant function, a step-like function, constant functions with undershoots and overshoots, a periodic function, monotonically increasing and decreasing functions). Our analysis shows that the dynamics of the rate of the resource flow defines the changes of the tendencies of the population sizes. Among the obtained solutions, there are solutions that lead to an equilibrium between populations. For people this equilibrium may be regarded as favorable if robots prefer to benefit from communication with people, but not from their extermination. However, equilibrium solutions imply a constant or slowly changes of the rate of the resource flow. Short-term changes of the rate of the resource flow modify the balance between the human population and the robot population. Accumulation of the changes can even lead to disappearance of one of the populations. Qualitative analyzes of the proposed system of differential equations along with computer simulations allow us to conclude that there are some necessary conditions for a well-being of the humans and robots. These conditions are as follows. Firstly, the benefit of the robot from communicating with people has to be higher than the benefit from their extermination. Secondly, to prevent the appearance of the aggressive robots the humanity has to regulate effectively the size of its own population. Thirdly, people have to be able to restrict their needs while maintaining the reproduction rate.

Determining the sources of growth of the cement industry in Iraq (analytical study for the period 1990-2014)

The objective of this study is to determine the sources of growth of the cement industry in Iraq for the period 1990-2014 and to indicate the nature of the technological progress used in it. To achieve this objective we have built an econometric model, by adapting the production function constant elasticity for substitution, using multiple regression, and enforcement, SPSS program, and using the ordinary least squares method (OLS). The results showed that quantitative factors (labour and capital) are the main sources of growth the cement industry in Iraq, and the qualitative factors (technological progress) did not contribute effectively to achieve this growth. And that the production techniques adopted in the cement industry in Iraq are labour intensive we recommend to raise the level of technology used in this industry and creating the cadres capable of dealing with this advanced technology, which requires changing some aspects of educational systems in the direction of vocational education.

Varying the Valuating Function and the Presentable Bank in Computerized Adaptive Testing

In computerized adaptive testing, the most commonly used valuating function is the Fisher information function. When the goal is to keep item bank security at a maximum, the valuating function that seems most convenient is the matching criterion, valuating the distance between the estimated trait level and the point where the maximum of the information function is located. Recently, it has been proposed not to keep the same valuating function constant for all the items in the test. In this study we expand the idea of combining the matching criterion with the Fisher information function. We also manipulate the number of strata into which the bank is divided. We find that the manipulation of the number of items administered with each function makes it possible to move from the pole of high accuracy and low security to the opposite pole. It is possible to greatly improve item bank security with much fewer losses in accuracy by selecting several items with the matching criterion. In general, it seems more appropriate not to stratify the bank.