Applying an Archetype-Based Approach to Electroencephalography/Event-Related Potential Experiments in the EEGBase Resource

PURPOSE: The purpose of this study is to investigate the feasibility of applying openEHR (an archetype-based approach for electronic health records representation) to modeling data stored in EEGBase, a portal for experimental electroencephalography/event-related potential (EEG/ERP) data management. The study evaluates re-usage of existing openEHR archetypes and proposes a set of new archetypes together with the openEHR templates covering the domain. The main goals of the study are to (i) link existing EEGBase data/metadata and openEHR archetype structures and (ii) propose a new openEHR archetype set describing the EEG/ERP domain since this set of archetypes currently does not exist in public repositories. METHODS: The main methodology is based on the determination of the concepts obtained from EEGBase experimental data and metadata that are expressible structurally by the openEHR reference model and semantically by openEHR archetypes. In addition, templates as the third openEHR resource allow us to define constraints over archetypes. Clinical Knowledge Manager (CKM), a public openEHR archetype repository, was searched for the archetypes matching the determined concepts. According to the search results, the archetypes already existing in CKM were applied and the archetypes not existing in the CKM were newly developed. openEHR archetypes support linkage to external terminologies. To increase semantic interoperability of the new archetypes, binding with the existing odML electrophysiological terminology was assured. Further, to increase structural interoperability, also other current solutions besides EEGBase were considered during the development phase. Finally, a set of templates using the selected archetypes was created to meet EEGBase requirements. RESULTS: A set of eleven archetypes that encompassed the domain of experimental EEG/ERP measurements were identified. Of these, six were reused without changes, one was extended, and four were newly created. All archetypes were arranged in the templates reflecting the EEGBase metadata structure. A mechanism of odML terminology referencing was proposed to assure semantic interoperability of the archetypes. The openEHR approach was found to be useful not only for clinical purposes but also for experimental data modeling

OCVD Carrier Lifetime in P+NN+ Diode Structures With Axial Carrier Lifetime Gradient

The OCVD (open circuit voltage decay) method is the generally used method for the determining of carrier lifetime in the structures of semiconductor devices. This paper is focused on power diode (PCNNC) structures, in which is realised a carrier lifetime gradient to influence the current and voltage waveforms during the reverse recovery process. A theoretical analysis of the general features of voltage decay courses in OCVD measurements on diode structures with an axial carrier lifetime gradient in the diode base is presented. Some results obtained from both simulations and experimental measurements are discussed in the paper

MEE (Materials Engineering for Electronics) - Aim, Tools and Perspectives

New approach to solidification processes based on a combination  of mechanical vibrations and on specially introduced magneto-hydrodynamic forces is illustrated on GaSb grown from Ga and Sb solutions. Process is accelerated approximately 20-times compared with "classical" Travelling heater method - solution growth. Up to now, though ingots possess mosaic texture, their transport properties: μH = 3.800 cm2/Vs, p = 1.7 . 1017 at 77 K are slightly better than published results. A schematic arrangement of the growth apparatus for a modified travelling heater method, and of the growth conditions are given. A simple calculation of levitation phenomenon being generated by a controlled MHD forces are presented. There is brought a brief analyses of this phenomenon for an application on the above mentioned processes. Some experimentation attempts are added. Possible perspectives inhering in this peculiar process can also inspire young investigators/scientists