Using web-based tools for teaching statistical concepts and experimentation skills
This paper describes a number of generally accessible web-based tools the authors developed over the last couple of years and used in several statistics courses, ranging from the introductory statistics course to a specialized design of experiments course. The first set of tools (VESTAC) illustrates statistical concepts, the second one (VIRTEX) consists of virtual experiments. We discuss some of our experiences with regard to the development and maintenance of these tools and their use in ex cathedra teaching sessions, in guided practice sessions and in student projects. Finally we discuss a third type of tools: distance experiments.
Teaching of Statistics
IN a paper read to the Royal Statistical Society on June 20, 1939, and printed, with the ensuing discussion, in its Journal (102, 532; 1939), Dr. John Wishart pointed out, among other things necessary for the progress of the subject, the urgent need for a standard treatise on its mathematical side. There are many text-books on practical statistical methods, usually restricted to one particular field of application, such as economics, business statistics, psychology, or biology and medicine, in which the reader has to accept the statements without proof. If a mathematical student asks where these proofs may be found, he may be told "You must look up the original papers, which you will not be able to understand". It is urgently necessary that a text-book should be produced to end this unsatisfactory state of affairs.
Simulation study of high power microwave generation by virtual cathode oscillation in coaxial vircator
Summary form only given, as follows. We have numerically simulated the high power microwave generation by virtual cathode oscillation in a coaxial vircator with 3 dimensional PIC code Magic. It is noted that the coaxial vircator has the advantage of an enhancement of power efficiency and gaining of narrow bandwidth frequency. The study is focused on the design of a diode structure for a coaxial vircator suitable for Chundoong IREB pulser (Max. 600 kV, 85 kA, 60 ns). It consists of a center annular cathode, a cylindrical meshed-anode and a reflector. The simulation results showed that the coaxial vircator can indeed be operated at the selected frequency with the narrow bandwidth and the microwave output power strongly depends on the position and geometry of the reflector. From this simulation results we expect that the maximum microwave output power will be obtained by the reflector of 4 cm in width and also 4 cm in distance away from the IREB, where the resonant frequency of microwave from coaxial vircator is simulated to be 6.577 GHz.