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In this paper, we present a passive tag for the determination of gaseous oxygen in intelligent packaging (IP). The power supply for this tag is obtained from thermoelectric energy harvesting taking advantage of the temperature difference between a cooled package and the human body. For this purpose, a compact Peltier module is attached to the surface of the package. This device is able to generate 1.2 mW when a temperature difference of 25 °C is applied between its surfaces. A dc-to-dc boost converter is included to generate an output voltage of 3.3 V and an output current of $225~\mu \text{A}$ from the harvested energy by the Peltier cell, which are used to supply the measurement circuitry. A luminescent membrane sensitive to oxygen is used as a gas detector in the package. The generated signal is compared to a reference value to evaluate if the oxygen concentration inside the package falls below or above a predetermined value. This is shown by turning on a green or a red LED, respectively. The proposed system presents a resolution of 0.02% of the predicted oxygen concentration in the range of interest (0%–5%) and a limit of detection (LOD) of 0.007%, which makes the instrument appropriate to be used in IP and active packaging (AP) technology. [ABSTRACT FROM AUTHOR]

The IMS Learning Design specification aims at capturing the complete learning flow of courses, without being restricted to a particular pedagogical model. Such flow description for a course, called a Unit of Learning, must be able to be reproduced in different systems using a so called run-time environment. In the last few years there has been several tools implementing such functionality, but most of them are standalone and do not benefit from the integration with a Learning Management System. This paper describes GRAIL, an IMS Learning Design run-time environment supporting all three levels of the specification and fully integrated with the .LRN Learning Management System. The paper describes its functionality, explains how each level is implemented, shows the differences with other CopperCore based environments, and analyzes its integration with the rest of .LRN services and other specifications such as QTI and SCORM. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including microstructural observations such as twin boundaries and dislocations, mechanical behavior of hexagonal close-packed (HCP) metals, and multiscale simulation and modeling of HCP materials' plastic deformation.