Image Analysis to Optimize Calculations of Grinding Modes

Modeling helps to investigate and analyze the interrelationships of grinding parameters as a single system. The article describes a computer model of the surface layer of a grinding wheel, taking into account the cutting modes and characteristics of the circle. The subsystem of the surface layer of the grinding wheel is the most important subsystem of grinding, since it connects the main characteristics of the circle with the cutting modes and with the parameters of the workpiece. The output characteristics of the model are the parameters of the working layer with a height of several micrometers, in which micro-cutting occurs. It is impossible (or very difficult) to obtain them by conducting full-scale experiments, since the processes are instantaneous, and the cutting elements have micro-dimensions. This problem was solved by creating a simulation stochastic model based on the geometric representation of the surface layer, which clearly displays the result. The analysis of the image of this model allowed us to numerically describe the output parameters of cutting. The article offers a faster algorithm for analyzing the image of the simulation model of the surface layer. It is carried out over a matrix containing numerical information about the projection of the surface layer, the main parameters of each single slice are calculated, and only after that the result is displayed on the graphic screen. To simulate a single grinding mode, it is necessary to repeat the process of "image creation - image analysis– output of results" hundreds of times until a stable state is reached. The use of the algorithm in an automated system will allow you to create a system for automatically searching for optimal grinding modes, as well as to derive analytical dependencies of cutting modes on input parameters, for example, on the parameters of the circle and the workpiece.

Computer Simulations of Astronomical Phenomena

The basic idea of this project is to introduce a senior student to an astronomical phenomenon that he analyses carefully and simulates on the graphic screen of a personal computer. In a second step, this simulation serves as a demonstration for junior students.Three examples are presented here: the retrograde motion of the planets, the Earth’s rotation, and the precession and the equilibrium figure of the Earth due to tides. Programs have been written on an IBM PC/AT.It would be highly desirable to start an exchange program of material of didatic interest among the international astronomical community

Transformação matemática utilizada na tela gráfica de microcomputador Apple

This work has as its main objective to present a way of transforming the high resolution graphic screen of the microcomputer, thus allowing the utilization of the standard system of cartesian coordinates. The transformation is done through the composition of a reflection RX and a translation TA. This work was developed in a microcomputer APPLE, D.O.S., 64 Kb, 8 Bits in BASIC language.

Interactive computer processing and interpretation of pumping test data. A Micro-computer program using dynamic graphics

This paper presents a computer program for analysing pumping test data. The program is interactive and may be used with a minimum knowledge of computers. It can be applied to a wide range of transient problem types, from one dimensional groundwater flow to flow in anisotropic aquifers, horizontally as well as vertically. Various forms of type curves based on analytical solutions to the groundwater flow equation are available for the interpretation. The paper includes a listing of the entire computer program containing a total of about 1. 800 lines. The programming language is a BASIC-version suited for the Tektronix 4054, a graphic screen with a refresh option. This option allows the user to perform type curve matching directly on the screen by moving the chosen type curve to the position where it gives the best fit, in a manner similar to traditional manual chart interpretation. Plots of the measured data may be conveniently reproduced in semilog and log-log diagrams, either on the screen or as a hard copy printed by a plotter. The present version of the program makes use of tape cartridges, both for storing program and data files.

An interactive program for the interpretation and simulation of Laue patterns

An interactive Fortran IV program is described which allows the orientation matrix of a crystal to be determined and refined without ambiguity, from a transmission or reflection Laue photograph. The indexing method is that of Riquet & Bonnet [J. Appl. Cryst. (1979), 12, 39–41] applied to a small number of data (less than ten) and adapted for interactive use. The verification of calculated solutions or even the trial-and-error search for the right solution is made by means of the visual comparison between the experimental diagram and simulated patterns displayed on a graphic screen. In addition, the rotation angles for setting the crystal to any new orientation may be computed.