Die Erstellung von Lerninhalten ist einer der wichtigsten Prozesse im E-Learning. Die vorliegende Arbeit zeigt einen Ansatz zur Wiederverwendung von Lerninhalten der zum einen die Kosten des Erstellungsprozesses verringern kann und zum anderen effektive Methoden zur Verwaltung aufzeigt. Basis des Ansatzes ist ein vierstufiges Content-Modell (Assets, Lernmaterialien, Lernmodule und Veranstaltungen), welches die Lerninhalte anhand der Granularität aufteilt. Dieses Modell berücksichtigt dabei aktuelle E-Learning-Standards bezüglich der Inhalte und der Metadaten, wodurch eine systemunabhängige Wiederverwendung möglich ist. Zur Verarbeitung von generischen Repräsentationen, wie Materialien im XML-Format, wurde das Konzept der Templates aufgegriffen und um die so genannten Content-Varianten erweitert. Diese ermöglichen die Präsentation von verschiedenen Ausprägungen der Materialien, beispielsweise bezüglich des Ausgabeformates, der Sprache, des Schwierigkeitsgrades von Aufgaben oder der Version. In der Arbeit wird weiterhin ein entsprechendes Konzept zur Systementwicklung einer Lernplattform aufgezeigt. Dieses ist insbesondere durch die Aufteilung in verschiedene Teilsysteme gekennzeichnet, welche eine flexible Konfiguration und Platzierung anhand der Anforderungen an die Wiederverwendung ermöglicht. / The preparation of learning content is one of the most important process in E-Learning. This thesis shows an approach to reuse learning content. On the one hand the costs of the creation process can be reduced and on the other hand effective methods for administration are pointed out. Starting point of the approach is a four-level content model (assets, learning materials, learning modules and seminars), which divides learning contents on the basis of granularity. This model considers thereby current E-Learning-standards concerning content and metadata, whereby an open reuse is possible. For the processing of generic representations, like materials in the XML format, the concept of the Templates was taken up and extended by the content variants. These make the presentation of different developments of the materials possible, for example concerning the output format, the language, the degree of difficulty of tasks or the version. Further this thesis pointed out an appropriate concept for the system development of a learning platform. This is in particular characterized by the partitioning into different subsystems, which makes possible a flexible configuration and placement concerning to the requirements to the reuse.

Refugees arriving in Europe face numerous socio-cultural challenges towards being integrated members of their host society. While acculturation strategies and ICT use of refugees have been studied separately, we investigate refugees’ smartphone use for acculturation by conducting qualitative interviews with 30 refugees. We contribute five practices related to acculturation that express refugees’ intercultural exchange within the host society while preserving their original culture: seek information online; communicate with family and friends abroad; meet locals; meet peers and counteract boredom. Tied to these practices, we find the five consequences empowerment, connection to host society, distraction, sense of belonging and connection to origin, which give an account of the various acculturation issues and how refugees use smartphones in support thereof.

The Zeitgeist project asks what role design students can play in enhancing creative endeavours and wellbeing of residents through an intergenerational co-design programme. Between Spring 2018 and Summer 2019, Zeitgeist brought together undergraduate design students and residents of long-term care homes for a project that challenged them to co-design publications that focused on the life experiences, stories and knowledge of the residents and emphasized an intergenerational exchange between two very different groups of people that could have a tangible, positive impact upon each other. It is often the case that residents in long-term care homes face issues of social isolation and diminishment of personal identity. In care homes opportunities for genuine creative and personal expression tend to be limited due to limited resources and a focus on medical priorities. It’s not unusual for residents to feel like they no longer have anything to contribute to society, that their story has closed and they no longer feel challenged, which can lead to cognitive decline. Design students are predominately young and tend to have limited life experience, with many still living at home and unsure about what direction they want their life to take. Zeitgeist looked to explore the possible benefits of a reciprocal relationship between the two parties by engaging participants in a range of creative activities that would allow for a mutual exchange of information and skills. This project uniquely positions an art and design university as a community partner for developing new approaches to enhance the wellbeing of seniors.

Advanced scanning magnetoresistive microscopy (SMRM) — a robust magnetic imaging and probing technique — is presented. It utilizes conventional recording heads of a hard disk drive as sensors. The spatial resolution of modern tunneling magnetoresistive sensors is nowadays comparable with more commonly used magnetic force microscopes. Important advantages of SMRM are the ability to detect pure magnetic signals directly proportional to the out-of-plane magnetic stray field, negligible sensor stray fields, and the ability to apply local bipolar magnetic field pulses up to 10 kOe with bandwidths from DC up to 1 GHz. The performance assessment of this method and corresponding best practices are discussed in the first section of this work. An application example of SMRM, the study on chemically ordered L10 FePt is presented in a second section. A constructed heater unit of SMRM opens the path to investigate temperature-dependent magnetic properties of the medium by recording and imaging at elevated temperatures. L10 FePt is one of the most promising materials to reach limits in storage density of future magnetic recording devices based on heat-assisted magnetic recording (HAMR). In order to be implemented in an actual recording scheme, the medium Curie temperature should be lowered. This will reduce the power requirements, and hence, wear and tear on a heat source — integrated plasmonic antenna. It is expected that the exchange coupling of FePt to thin Fe layers provides high saturation magnetization and elevated Curie temperature of the composite. The addition of Cu allows adjusting the magnetic properties such as perpendicular magnetic anisotropy, coercivity, saturation magnetization, and Curie temperature. This should lead to a lowering of the switching field of the hard magnetic FeCuPt layer and a reduction of thermally induced recording errors. In this regard, the influence of the Fe layer thickness on the switching behavior of the hard layer was investigated, revealing a strong reduction for Fe layer thicknesses larger than the exchange length of Fe. The recording performance of single-layer and bilayer structures was studied by SMRM roll-off curves and histogram methods at temperatures up to 180 °C In the last section of this work, SMRM advantages are demonstrated by various experiments on a two-dimensional magnetic vortex lattice. Magnetic vortex is a peculiar complex magnetization configuration which typically appears in a soft magnetic structured materials. It consists of two coupled sub-systems: the core, where magnetization vector points perpendicular to the structure plane, and the curling magnetization where magnetic flux is rotating in-plane. The unique properties of a magnetic vortex making it an object of a great research and technological interest for spintronic applications in sensorics or data storage. Manipulation of the vortex core as well as the rotation sense by applying a local field pulse is shown. A spatially resolved switching map reveals a significant "write window" where vortex cores can be addressed correctly. Moreover, the external in-plane magnet extension unit allow analyzing the magnetic vortex rotational sense which is extremely practical for magnetic coupling investigations of magnetic coupling phenomena.

One of the unsolved problems of modern science is whether the pre-Columbian peoples of the New World developed completely independently of cultural influences from the Old World or if there was a trans-oceanic contact? A number of scientists agree that there are many – and often remarkable – similarities between the cultures of pre-Columbian America and those of the Mediterranean world. Nevertheless, there is no agreement, as yet, on how cultural diffusion can be differentiated from independent invention. Scientific analysis shows that scholarly positions are often strongly pre-formed from paradigms (scientific based assumptions), which tend to hinder consideration of solid scientific data offered by geo-biology and its trans-disciplinary examination of the subject under investigation here. An unambiguous answer to the question, what historical processes led to the emergence of the ancient American agriculture, hasn\'t been given. However, the archaeological discovery of crops with clear trans-oceanic origin, in addition to advances in molecular biology, increasingly support the hypothesis that humans from the distant past influenced each other across the oceans at a much earlier stage. The vegetation and zoo-geography indicate, by numerous examples that some species could only have spread through perhaps unintentional (passive) human transmission [1]. There are two very old crops found in the „New World‟, which contradict the paradigm of a completely independent origin for American agriculture. These are the African Bottle Gourd (Lagenaria siceraria L.) and the ancestral cotton species (Gossypium herbaceum L.) of the domesticated spin able sub-genus of tetraploid cotton. The historical spread of both types has been under discussion for decades, especially in respect of trans-oceanic human contact with the American continent. There has also been a debate in the \"Old World\" ever since the discovery of nicotine and cocaine in Egyptian mummies, centering around whether \"New World\" plants (or the ingredients) might have been transmitted in the reverse direction, back to the presumed start in centers of the Ancient World\'s oldest civilizations.

Einleitung In einem größeren Universitätsklinikum wie in der Charité sind EDV-gestützte Verfahren in verschiedenen Einrichtungen und für verschiedene Aufgaben im Einsatz: Verwaltung, Krankenversorgung, Forschung und Lehre. Diese Subsysteme sind in der Regel nicht in der Lage, Daten untereinander so auszutauschen, daß die in den Daten enthaltene Semantik nicht verlorengeht. Die Ursache liegt im wesentlichen in der Komplexität und in der Unschärfe der medizinischen Informationen. Medizinische Standards (HL7, DICOM, SNOMED, ICD, ICPM, ...) lassen sich für den Austausch von Daten verwenden, die gut formalisierbar und mit einer klaren Bedeutung behaftet sind. Nicht formalisierbare Daten, die z. B. in einem Befund oft vorkommen, lassen sich nicht ohne weiteres mit diesen Standards darstellen. Ziel Entwicklung eines Konzeptes für den Austausch medizinischer Daten, das die o. g. Probleme vermeidet. Material und Methoden Die Analyse der vorhandenen Subsysteme, Standards und Konzepte zeigt, daß das Konzept einerseits eine sehr einfache Syntax und eine simple Struktur aufweisen muß. Andererseits muß die medizinische Semantik voll erhalten bleiben. Als Vorbild kann die relationale Datenbank dienen, die mit einem Datentyp (Relation bzw. Tabelle) und einem einzigen Operator (SELECT) auf diesen Datentyp auskommt. Ergebnisse Das Konzept ist objektorientiert. Es enthält nur einen Datentyp. Das ist das AMICI-Objekt (AMICI: Architecture for Medical Information Exchange and Communication Interface). Über dieses AMICI-Objekt wird der gesamte Datenaustausch vorgenommen. Kann das Empfängersystem ein Objekt nicht oder nicht korrekt interpretieren, so wird die Interpretation vom Sendesystem übernommen. Ein Subsystem wird im Netzwerk über einen medizinischen Kontext angeschlossen, der das Interessengebiet und die Fähigkeit des Subsystems beschreibt. Das Subsystem kann an Hand der im Netz bekannten medizinischen Kontexte feststellen, welche weiteren Subsysteme für den eigenen Zweck interessant sein könnten. Alle AMICI-Objekte erhalten eine weltweit eindeutige Identifikation, so daß die Daten aus verschiedenen Institutionen, auch international, miteinander gemischt werden können. Diskussion Das Konzept kann als Basis für weitere Dienstleitungen in einem Klinikum bzw. einem Krankenhaus dienen. Namentlich zu nennen sind telemedizinische Anwendungen, bei denen nicht nur die Kommunikation zwischen Ärzten, sondern auch zwischen Patienten und Arzt möglich ist. Weiterhin betrifft dies den Einsatz von Software-Agenten, die sich um den Informationsbedarf eines Arztes individuell kümmern. / Introduction Large hospitals like the University hospital Charité use in different units different information systems for recording patient and medical data. There are also different tasks: administration, healthcare, research and education. These medical information systems are often called subsystems. They are usually not able to exchange data without lost of semantic. The complexity and the variability of medical terminology cause this problem. Existing medical standards (e. g. HL7, DICOM, SNOMED, ICD, ICPM, ...) are helpful for well formalised terms. Non-formalised terms that are often used in diagnostic reports can not be represented by existing standards. Aims Development of a concept for medical information exchange which fulfills the requirements mentioned above. Material and Methods The system analysis that is performed based on existing subsystems, medical standards and concepts provides two essential requirements. On the one hand the syntax of such standard must be extremely simple. On the other hand the standard must be able to transfer extremely complex semantics. As an example relational databases (RDB) provide a good idea of such simple syntax and complex semantics. RDB's include only one data type. It is called relation or table. To manipulate tables one needs only one operation. That is the SELECT command in SQL. Result The concept is object oriented. It includes only one object called AMICI-object like RDB's (AMICI: Architecture for Medical Information Exchange and Communication Interface). Data exchange is completely performed by these AMICI-objects. If the receiving subsystem is not able to interpret and represent an object, the sending subsystem will take over this task. Within a network a subsystem uses a special AMICI-object called medical context to describe its features and its area of interest. A subsystem can inquire medical contexts to explore installed and running subsystems in the network. An international unique identifier identifies every AMICI object so that you can mix objects provided by different international institutions, e. g. to use them in multi-center-studies. Discussion This concept can also be used as a basic service for higher level applications in a hospital. Two of them are telemedicine and software agents. Telemedicine is not only a tool for physicians. It should be also a tool for communication and interaction between patient and physician. Physicians can use personal software agents for information acquisition, which meets exactly his specific requirements.

In this thesis multidomain states in magnetically ordered systems with competing long-range and short range interactions are under consideration. In particular, in antiferromagnetically coupled multilayers with perpendicular anisotropy unusual multidomain textures can be stabilized due to a close competition between long-range demagnetization fields and short-range interlayer exchange coupling. These spatially inhomogeneous magnetic textures of regular multidomain configurations and irregular networks of topological defects as well as complex magnetization reversal processes are described in the frame of the phenomenological theory of magnetic domains. Using a modified model of stripe domains it is theoretically shown that the competition between dipolar coupling and antiferromagnetic interlayer exchange coupling causes an instability of ferromagnetically ordered multidomain states and results in three possible ground states: ferromagnetic multidomain state, antiferromagnetic homogeneous and antiferromagnetic multidomain states. The presented theory allows qualitatively to define the area of existence for each of these states depending on geometrical and material parameters of multilayers. In antiferromagnetically coupled superlattices with perpendicular anisotropy an applied magnetic bias field stabilizes specific multidomain states, so-called metamagnetic domains. A phenomenological theory developed in this thesis allows to derive the equilibrium sizes of metamagnetic stripe and bubble domains as functions of the antiferromagnetic exchange, the magnetic bias field, and the geometrical parameters of the multilayer. The magnetic phase diagram includes three different types of metamagnetic domain states, namely multidomains in the surface layer and in internal layers, and also mixed multidomain states may arise. Qualitative and quantitative analysis of step-like magnetization reversal shows a good agreement between the theory and experiment. Analytical equations have been derived for the stray field components of these multidomain states in perpendicular multilayer systems. In particular, closed expressions for stray fields in the case of ferromagnetic and antiferromagnetic stripes are presented. The theoretical approach provides a basis for the analysis of magnetic force microscopy (MFM) images from this class of nanomagnetic systems. Peculiarities of the MFM contrast have been calculated for realistic tip models. These characteristic features in the MFM signals can be employed for the investigations of the different multidomain modes. The methods developed for stripe-like magnetic domains are employed to calculate magnetization processes in twinned microstructures of ferromagnetic shape-memory materials. The remarkable phenomenon of giant magnetic field induced strain transformations in such ferromagnetic shape memory alloys as Ni-Mn-Ga, Ni-Mn-Al, or Fe-Pd arises as an interplay of two physical effects: (i) A martensitic transition creating competing phases, i.e. crystallographic domains or variants, which are crystallographically equivalent but have different orientation. (ii) High uniaxial magnetocrystalline anisotropy that pins the magnetization vectors along certain directions of these martensite variants. Then, an applied magnetic field can drive a microstructural transformation by which the martensitic twins, i.e. the different crystallographic domains, are redistributed in the martensitic state. Within the phenomenological (micromagnetic) theory the equilibrium parameters of multivariant stripe patterns have been derived as functions of the applied field for an extended single-crystalline plate. The calculated magnetic phase diagram allows to give a detailed description of the magnetic field-driven martensitic twin rearrangement in single crystals of magnetic shape-memory alloys. The analysis reveals the crucial role of preformed twins and of the dipolar stray-field energy for the magnetic-field driven transformation process in magnetic shape-memory materials. This work has been done in close collaboration with a group of experimentalists from Institute of Metallic Materials of IFW Dresden, Germany and San Jose Research Center of Hitachi Global Storage Technologies, United States. Comparisons between theoretical and experimental data from this cooperation are presented throughout this thesis as vital part of my work on these different subjects.

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In this thesis multidomain states in magnetically ordered systems with competing long-range and short range interactions are under consideration. In particular, in antiferromagnetically coupled multilayers with perpendicular anisotropy unusual multidomain textures can be stabilized due to a close competition between long-range demagnetization fields and short-range interlayer exchange coupling. These spatially inhomogeneous magnetic textures of regular multidomain configurations and irregular networks of topological defects as well as complex magnetization reversal processes are described in the frame of the phenomenological theory of magnetic domains. Using a modified model of stripe domains it is theoretically shown that the competition between dipolar coupling and antiferromagnetic interlayer exchange coupling causes an instability of ferromagnetically ordered multidomain states and results in three possible ground states: ferromagnetic multidomain state, antiferromagnetic homogeneous and antiferromagnetic multidomain states. The presented theory allows qualitatively to define the area of existence for each of these states depending on geometrical and material parameters of multilayers. In antiferromagnetically coupled superlattices with perpendicular anisotropy an applied magnetic bias field stabilizes specific multidomain states, so-called metamagnetic domains. A phenomenological theory developed in this thesis allows to derive the equilibrium sizes of metamagnetic stripe and bubble domains as functions of the antiferromagnetic exchange, the magnetic bias field, and the geometrical parameters of the multilayer. The magnetic phase diagram includes three different types of metamagnetic domain states, namely multidomains in the surface layer and in internal layers, and also mixed multidomain states may arise. Qualitative and quantitative analysis of step-like magnetization reversal shows a good agreement between the theory and experiment. Analytical equations have been derived for the stray field components of these multidomain states in perpendicular multilayer systems. In particular, closed expressions for stray fields in the case of ferromagnetic and antiferromagnetic stripes are presented. The theoretical approach provides a basis for the analysis of magnetic force microscopy (MFM) images from this class of nanomagnetic systems. Peculiarities of the MFM contrast have been calculated for realistic tip models. These characteristic features in the MFM signals can be employed for the investigations of the different multidomain modes. The methods developed for stripe-like magnetic domains are employed to calculate magnetization processes in twinned microstructures of ferromagnetic shape-memory materials. The remarkable phenomenon of giant magnetic field induced strain transformations in such ferromagnetic shape memory alloys as Ni-Mn-Ga, Ni-Mn-Al, or Fe-Pd arises as an interplay of two physical effects: (i) A martensitic transition creating competing phases, i.e. crystallographic domains or variants, which are crystallographically equivalent but have different orientation. (ii) High uniaxial magnetocrystalline anisotropy that pins the magnetization vectors along certain directions of these martensite variants. Then, an applied magnetic field can drive a microstructural transformation by which the martensitic twins, i.e. the different crystallographic domains, are redistributed in the martensitic state. Within the phenomenological (micromagnetic) theory the equilibrium parameters of multivariant stripe patterns have been derived as functions of the applied field for an extended single-crystalline plate. The calculated magnetic phase diagram allows to give a detailed description of the magnetic field-driven martensitic twin rearrangement in single crystals of magnetic shape-memory alloys. The analysis reveals the crucial role of preformed twins and of the dipolar stray-field energy for the magnetic-field driven transformation process in magnetic shape-memory materials. This work has been done in close collaboration with a group of experimentalists from Institute of Metallic Materials of IFW Dresden, Germany and San Jose Research Center of Hitachi Global Storage Technologies, United States. Comparisons between theoretical and experimental data from this cooperation are presented throughout this thesis as vital part of my work on these different subjects.

Der vorliegende Bericht richtet sich an die beteiligten Akteure der Demografie-Fokus-Reihe und an alle, die an den Ergebnissen der Fokus-Reihe interessiert sind. Die Veranstaltungsreihe wurde im Rahmen des Landesförderprogramms Demografie und unter Begleitung der Sächsischen Staatskanzlei unterstützt. Konzeption und Durchführung lagen in der Hand der Arbeitsgemeinschaft Panse + Wend. Redaktionsschluss: 30.01.2018