Search

{We herein report on the calculation of thermoluminescence (TL) kinetic parameters determined from the TL emission of synthetic GdAlO3 (GAO) phosphors prepared by the co-precipitation method. The sample, characterized by means of X-ray diffraction with an orthorhombic phase structure (space group Pnma (62), shows complex glow curves consisting of at least four groups of components peaked at 100, 140, 240, and 290 {\deg}C where the two lower overlapped temperature peaks are difficult to identify using the $T_M-T_{stop}$. The coexistence of a continuum in the trap distribution (linked to the lower temperature peaks) and a discrete trap system (associated with the components at temperatures higher than 200 {\deg}C) can be distinguished. The estimation of the TL kinetic parameters is performed using GlowFit, TLAnal, the spreadsheet Origin, Computing Glow Curve Deconvolution (CGCD), and various heating rate (VHR) methods. However, only CGCD appears as the suitable technique for such purpose since it provides information on the TL physical process supported by mathematical models based on a linear combination of functions related to the First Order Kinetic approach., Comment: 27 pages, 6 figures and 1 table

Thermoluminescence (TL) characteristics for LiF:Mg,Cu,P, and CaSO$_4$:Dy under the homogeneous field of X-ray beams of diagnostic irradiation and its verification using thermoluminescence dosimetry is presented. The irradiation were performed utilizing a conventional X-ray equipment installed at the Hospital Ju\'arez Norte of M\'exico. Different thermoluminescence characteristics of two material were studied, such as batch homogeneity, glow curve, linearity, detection threshold, reproducibility, relative sensitivity and fading. Materials were calibrated in terms of absorbed dose to the standard calibration distance and they were positioned in a generic phantom. The dose analysis, verification and comparison with the measurements obtained by the TLD-100 were performed. Results indicate that the dosimetric peak appears at 202$^o$C and 277.5$^o$C for LiF:Mg,Cu,P and CaSO$_4$:Dy, respectively. TL response as a function of X-ray dose showed a linearity behavior in the very low dose range for all materials. However, the TLD-100 is not accurate for measurements below $4mGy$. CaSO$_4$:Dy is 80\% more sensitive than TLD-100 and it show the lowest detection threshold, whereas LiF:Mg,Cu,P is 60\% more sensitive than TLD-100. All material showed very good repeatability. Fading for a period of one month at room temperature showed low fading LiF:Mg,Cu,P, medium and high for TLD-100 and CaSO$_4$:Dy. The results suggest that CaSO$_4$:Dy and LiF:Mg,Cu,P are suitable for measurements at low doses used in radiodiagnostic., Comment: 7 pages, 8 figures

Intelligent Agents are being applied in a wide range of processes and everyday applications. Their development is not new, in recent years they have had an increased attention and design in learning and as mentoring tools. In this paper we discuss the definition of what an intelligent agent is; how they are applied; how thy look like; recent implementations of agents; agents as support in learning process; their state in Latin-American countries and future developments and trends that will permit a better communication between people and agents., Comment: 6 pages

This paper has been withdrawn by the author due to a crucial sign error in equation 1, Comment: This paper has been withdrawn by the author due to a crucial sign error in equation 1