An investigation of the grinding wheel wear with the use of root-mean-square value of acoustic emission
This paper presents the results of an investigation of the grinding wheel wear in a peripheral surface grinding process. During this investigation varying geometrical parameters of an active grinding wheel surface have been measured and the components of the grinding force and acoustic emission signal have been recorded. On the basis of these output quantities an analysis has been conducted of an acoustic emission descriptor's practicability, i.e. a root-mean-square (RMS) value, to characterize the cutting abilities of a grinding wheel in the time progress of its work. This article also presents a new energy coefficient, which determines the rate of grinding wheel wear in the form of a RMS value of acoustic emission signal falling on a contact surface of a grinding wheel. Moreover, the article presents some examples of a correlation between the root-mean-square value of acoustic emission signal and the surface roughness of a workpiece, which shows that the parameters of acoustic emission signal can be a useful tool to monitor the surface roughness during the grinding process.
Surface evaluation during the grinding process using acoustic emission signal
The hereby article presents results of experimental tests which prove the possibility of indirect eval uation of the grinded object’s quality with the application of mo nitoring and analysis of selected acoustic emission ig al (AE) registered during the machining process. As th e grinding process is carried out and the grinding wheel wear progresses, the acoustic emission signal value is s haped adequately to the workpiece surface quality c hanges. The binding descriptor of changes of roughness prof ile and material residual stresses is the RMS value of the acoustic emission signal and in particular the stat istical features that characterize the distribution of values contained in the signal sample in relation to the a v r ge value. The analysis results indicate that th e acoustic emission signal is a convenient indicator for evalu ation of stresses cumulated in the surface layer of the material and in selected surface geometrical structure param eters.
On Hilbert's thirteenth problem and related questions
Hilbert's thirteenth problem involves the study of solutions of algebraic equations. The object is to obtain a complexity estimate for an algebraic function. As of now, the problem remains open. There are only a few partial algebraic results in this connection, but at the same time the problem has stimulated a series of studies in the theory of functions with their subsequent applications. The most brilliant result in this cycle is Kolmogorov's theorem on superpositions of continuous functions.