Algorithmic complexity of quantum capacity

Recently the theory of communication developed by Shannon has been extended to the quantum realm by exploiting the rules of quantum theory. This latter stems on complex vector spaces. However complex (as well as real) numbers are just idealizations and they are not available in practice where we can only deal with rational numbers. This fact naturally leads to the question of whether the developed notions of capacities for quantum channels truly catch their ability to transmit information. Here we answer this question for the quantum capacity. To this end we resort to the notion of semi-computability in order to approximately (by rational numbers) describe quantum states and quantum channel maps. Then we introduce algorithmic entropies (like algorithmic quantum coherent information) and derive relevant properties for them. Finally we define algorithmic quantum capacity and prove that it equals the standard one

The Effect of P-Wave Propagation on the Seismic Behavior of Steel Pipelines

Underground structures perceived as one the most vital infrastructures,which include a variety of tunnels, subway lines,gas, oil and water pipe. Plenty of studies devoted to the investigationof the effect of wave propagation method on the seismicbehavior of steel pipelines. It should be mentioned thatanalyses have been carried out on both clayey and sandy soilwith different propagation speed in each of them. The aim ofthis research is the investigation of the effect of longitudinalp-wave propagation method on the amount of nonlinear strainsof pipeline with different way such as Pipe and Psi element or2D modelling of soil. It became evident that the amounts ofMaximum tension strain produced in the pipe have the maximumdifference, equaling 3.4 per cent. In addition, it investigatesthe effect of frequency of input motion on nonlinearstrains and the effect of frequency content in the results. &nbsp

Methods for evaluating effect of operators on drag line energy efficiency

Draglines are dominant machines and the most significant electricity consumers in surface coal mines. With the growing price of energy, environmental concerns, and the high sensitivity of mine profitability to dragline productivity, any improvement in efficiency of dragline will be beneficial for mines. Research has shown that operator practices have a significant impact on energy efficiency of mining loading tools. However, not enough work has been done to provide guidance on how to quantitatively assess the effect of operator practices on dragline energy efficiency. The objectives of this work were to: (i) test the hypothesis that dragline operator\u27s practices and skills significantly affect dragline energy efficiency; and (ii) develop a methodology to identify the critical parameters that explain the differences in operator energy efficiency. Statistical tests are suggested to study the effect of operator practice and skills on dragline energy efficiency to achieve the first research objective. The second objective was achieved with a novel methodology based on sound statistical principles. Both approaches were illustrated with a real-life dragline operation. The suggested methodology was used on the data collected from an 85yd³ BE-1570w dragline to compare the energy efficiency of five operators during a one month period. Valid methods have been formulated for testing operator effects on dragline energy efficiency and for identifying critical parameters that explain such differences. Using the developed approaches, the case study shows that operator practices can affect dragline energy efficiency. The tests show that there is a high probability that differences in energy efficiency are due to dumping height, vertical and horizontal drag distances, and spotting and dumping time among the surveyed operators --Abstract, page iii

Analyzing and Comparing the Effects of two Teaching Methods, Student-Centered Versus Teacher-Centered, on the Learning of Biostatistics at SBMU

Because of its widespread needs in different scientific fields, Statistics and Probability theory have gained great importance and medical students as well as students of other medically related disciplines including nursing need to use them especially in their research projects in undergraduate, graduate and postgraduate schools. This article deals with the question of finding the most effective way of teaching the necessary statistical skills to these students so that they can acquire more statistical knowledge and develop better problem solving and decision making strategies. This semi-experimental study has been carried out to compare the effect of teacher-centered and student-centered methods on nursing students’ learning of Biostatistics. The sample includes all the undergraduates of nursing School at SBMU (2006-2007). The sampling method used is convenience and includes 118 subjects. The teaching method is the dependent variable and the amount of material absorbed by the students, their age, marital status, type of housing, average of high school diploma, the grade average of the previous semester, number of family members and their prior experience are the independent variables. The grades of the students in the final exam, was taken as measure of amount of material absorbed by the students. The analysis was carried out using SPSS16 and the statistical tests used were t-test, ANOVA, and correlation test. The data revealed that the average of the students receiving student-based instruction was higher than the other students. However, no statistically significant difference was observed between the control and the experimental group in terms of the amount of teaching material learnt. The data also indicate that marital status, employment status, type of housing and prior experience all have statistically significant effect on the final grade, but none of them along with the teaching method exhibits a significant interaction with the final grade. Also the amount of material learnt by each student is almost directly correlated with his/her average of the previous semester (rp=0.402, p<0.001) and inversely weakly correlated with his/her age (rs=-0.220, p=0.017). Thus one can conclude that student-centered instruction is as effective as the teacher-centered instruction and other factors besides the method of instruction have a significant impact on the student’s learning.