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Objectives FHIR (Fast Healthcare Interoperability Resources) is an emerging Stan¬dard for improving interoperability in the domain of health care. Besides offering features for achieving syntactical, semantical and organizational interoperability, it also specifies a RESTful API for searching purposes. The main objective of the following thesis revolves around investigating open challenges and limitations of the so-called FHIR Search Framework.
Methods A variety of operations for searching in FHIR resources, including all search interactions, definitions of search parameters, search parameter types and advanced search concepts are described. Over the course of the thesis, a quality model based on ISO 25010 is established. It serves as the foundation for determining if the FHIR Search Framework is well-suited to cover the Information needs of its users. An analysis of completeness involving the measures defined in the quality model forms the main contribution. The primary discussion of the research questions is concluded by proposing a graph model for determining reachability between FHIR resources, essentially mirroring the chaining and reverse chaining functionality. Using well-known classes for expressiveness in graphs, the thesis assess to which degree a graph search can be formulated with the currently defined capabilities.
Results From a functional perspective the FHIR Search Framework can be considered well-suited. Practical limitations should be minimal, grounded on the fact that extensive coverage of the lowest expressiveness classes, RPQs and 2RPQs, can be achieved. Severe gaps where identified only in the support of C(2)RPQs and Data Path Queries. Additionally, ideas for improving non-functional aspects are introduced to support developers in learning the Standard and testing their implementations.
Conclusion The evaluation of the FHIR Search Framework showed promising re¬sults in terms of functional completeness. Yet, the Standard is still evolving, and certain parts of the Search API are neither well-known nor implemented widely. A discussion is to be held if the specification should cover more sophisticated aspects that result from the gaps which were identified.
As a customer, it can be frustrating to face an empty shelf in a store. The market does not always realize that a product has been out of stock for a while, as the item is still listed as in stock in the inventory management system. To address this issue, a camera should be used to check for Out-of-Stock (OOS) situations.
This master thesis evaluates different model configurations of Artificial Neural Networks (ANNs) to determine which one best detects OOS situations in the market using images. To create a dataset, 2,712 photos were taken in six stores. The photos clearly show whether there is a gap on the shelf or if the product is in stock. Based on the pre-trained VGG16 model from Keras, two fully connected layers were implemented, with 36 different ANNs differing in the optimization method and activation function pairings. In total, 216 models were generated in this thesis to investigate the effects of three different optimization methods combined with twelve different activation function pairings. An almost balanced ratio of OOS and in-stock data was used to generate these models.
The evaluation of the generated OOS models shows that the FTRL optimization method achieved the least favorable results and is therefore not suitable for this application. Model configurations using the Adam or SGD optimization methods achieve much better results. Of the top six model configurations, five use the Adam optimization method and one uses SGD. They all achieved an accuracy of at least 93% and were able to predict the Recall for the OOS class with at least 91%.
As the data ratio between OOS and in-stock data did not correspond to reality in the previously generated models, the in-stock images were augmented. Including the augmented images, new OOS models were generated for the top six model configurations. The results of these OOS models show no convergences. This suggests that more epochs in the training phase lead to better results. However, the results of the OOS model using the Adam optimization method and the Sigmoid and ReLU activation functions stand out positively. It achieved the best result with an accuracy of 97.91% and a Recall of the OOS class of 87.82%.
Overall, several OOS models have the potential to increase both market sales and customer satisfaction. In a future study, the OOS models should be installed in the market to evaluate their performance under real conditions. The resulting insights can be used for continuous optimization of the model.
Academic search systems aid users in finding information covering specific topics of scientific interest and have evolved from early catalog-based library systems to modern web-scale systems. However, evaluating the performance of the underlying retrieval approaches remains a challenge. An increasing amount of requirements for producing accurate retrieval results have to be considered, e.g., close integration of the system’s users. Due to these requirements, small to mid-size academic search systems cannot evaluate their retrieval system in-house. Evaluation infrastructures for shared tasks alleviate this situation. They allow researchers to experiment with retrieval approaches in specific search and recommendation scenarios without building their own infrastructure. In this paper, we elaborate on the benefits and shortcomings of four state-of-the-art evaluation infrastructures on search and recommendation tasks concerning the following requirements: support for online and offline evaluations, domain specificity of shared tasks, and reproducibility of experiments and results. In addition, we introduce an evaluation infrastructure concept design aiming at reducing the shortcomings in shared tasks for search and recommender systems.
Communities That Care“ (kurz: CTC) ist ein sozialraumorientiertes Programm, das in fünf Phasen soziale Prävention in Stadtteilen installiert. Zentrale Elemente von CTC sind die regelmäßige Durchführung von Schülerbefragungen, aus deren Ergebnissen sich Schutz- und Risikofaktoren ableiten lassen. Die im Sozialraum ausgewählten sozialen Maßnahmen orientieren sich an den ausgewählten Schutz- und Risikofaktoren.
In Deutschland wurde das Programm seit dem Jahr 2008 in drei Standorten in Niedersachsen implementiert und erprobt. Das vorliegende Buch fasst die Ergebnisse der Evaluation zusammen. Neben den theoretischen Grundlagen und internationalen Erfahrungen mit CTC wird die Implementation von CTC in Niedersachsen dargestellt. In einer abschließenden Synthese werden Schlussfolgerungen und Empfehlungen für die Transferfähigkeit in andere Sozialräume und Passungsprobleme von CTC abgeleitet.
Observational studies and clinical trials have become increasingly important over recent years and play an essential role in advancing medical knowledge. In today’s world of clinical research, it is not possible to imagine trials without the founda-tion of a well-established it-infrastructure. Electronic capture and usage of data is pervasive.
In practice, medical progress requires the ability to integrate data from different systems. An essential factor in enabling different actors, such as institutions and hospitals, to have their systems exchange structured data and make use of the information is the interoperability of the data and systems.
FHIR (Fast Healthcare Interoperable Resources) is a free and easily customizable HL7 platform standard, based on 30 years of experience of HL7. It is focused on providing health-related information and defines a set of capabilities used in the health care process.
This thesis will provide a conceptual approach for working with FHIR, as well as concrete approaches for working with FHIR profiles and for customizing the standard for particular use cases. It will be carried out in cooperation with the Medical Systems R&D, which is a service provider within the University Hospital of Cologne.
The guiding request approach will focus on the evaluation of requirements for clini-cal trials and how clinical research protocols can be represented in an interoperable and machine-parsable format using FHIR.
Pelleted biomass has a low, uniform moisture content and can be handled and stored cheaply and safely. Pellets can be made of industrial waste, food waste, agricultural residues, energy crops, and virgin lumber. Despite their many desirable attributes, they cannot compete with fossil fuel sources because the process of densifying the biomass and the price of the raw materials make pellet production costly.
Leaves collected from street sweeping are generally discarded in landfills, but they can potentially be valorized as a biofuel if they are pelleted. However, the lignin content in leaves is not high enough to ensure the physical stability of the pellets, so they break easily during storage and transportation. In this study, the use of eucalyptus kraft lignin as an additive in tree-leaf pellet production was studied. Results showed that when 2% lignin is added the abrasion resistance can be increased to an acceptable value. Pellets with added lignin fulfilled all requirements of European standards for certification except for ash content. However, as the raw material has no cost, this method can add value or contribute to financing continued sweeping and is an example of a circular economy scenario.
Im Jahr 2007 wurden die „Ethischen Grundsätzen für Bibliotheks- und Informationsberufe“ in Deutschland verfasst. Es handelt sich hier um einen beruflichen Verhaltenskodex, der Richtlinien für angemessenes Verhalten für Bibliotheksbeschäftigte vorgibt. Die vorliegende Arbeit beschäftigt sich damit, aus welchen Gründen und in welchen Verfahren der Ethikkodex erstellt wurde. Weiterhin werden der Stand der Diskussion und die öffentliche Wahrnehmung des Kodexes innerhalb des deutschen Bibliothekswesens untersucht. Eine inhaltliche Analyse stellt fest, welche Kernaussagen innerhalb des Kodexes getroffen werden. Der deutsche Ethikkodex wird in Bezug auf Entstehung und Inhalt exemplarisch mit Ethikkodizes aus den USA und Estland verglichen. Dieser Vergleich ermöglicht es, Rückschlüsse darüber zu ziehen, inwieweit der Inhalt gelungen und der Entstehungsprozess nachvollziehbar ist und an welchen Stellen Überarbeitungsbedarf erkennbar ist.
In child–robot interaction (cHRI) research, many studies pursue the goal to develop interactive systems that can be applied in everyday settings. For early education, increasingly, the setting of a kindergarten is targeted. However, when cHRI and research are brought into a kindergarten, a range of ethical and related procedural aspects have to be considered and dealt with. While ethical models elaborated within other human–robot interaction settings, e.g., assisted living contexts, can provide some important indicators for relevant issues, we argue that it is important to start developing a systematic approach to identify and tackle those ethical issues which rise with cHRI in kindergarten settings on a more global level and address the impact of the technology from a macroperspective beyond the effects on the individual. Based on our experience in conducting studies with children in general and pedagogical considerations on the role of the institution of kindergarten in specific, in this paper, we enfold some relevant aspects that have barely been addressed in an explicit way in current cHRI research. Four areas are analyzed and key ethical issues are identified in each area: (1) the institutional setting of a kindergarten, (2) children as a vulnerable group, (3) the caregivers’ role, and (4) pedagogical concepts. With our considerations, we aim at (i) broadening the methodology of the current studies within the area of cHRI, (ii) revalidate it based on our comprehensive empirical experience with research in kindergarten settings, both laboratory and real-world contexts, and (iii) provide a framework for the development of a more systematic approach to address the ethical issues in cHRI research within kindergarten settings.
Conventional individual head-related transfer function (HRTF) measurements are demanding in terms of measurement time and equipment. For more flexibility, free body movement (FBM) measurement systems provide an easy-to-use way to measure full-spherical HRTF datasets with less effort. However, having no fixed measurement installation implies that the HRTFs are not sampled on a predefined regular grid but rely on the individual movements of the subject. Furthermore, depending on the measurement effort, a rather small number of measurements can be expected, ranging, for example, from 50 to 150 sampling points. Spherical harmonics (SH) interpolation has been extensively studied recently as one method to obtain full-spherical datasets from such sparse measurements, but previous studies primarily focused on regular full-spherical sampling grids. For irregular grids, it remains unclear up to which spatial order meaningful SH coefficients can be calculated and how the resulting interpolation error compares to regular grids. This study investigates SH interpolation of selected irregular grids obtained from HRTF measurements with an FBM system. Intending to derive general constraints for SH interpolation of irregular grids, the study analyzes how the variation of the SH order affects the interpolation results. Moreover, the study demonstrates the importance of Tikhonov regularization for SH interpolation, which is popular for solving ill-posed numerical problems associated with such irregular grids. As a key result, the study shows that the optimal SH order that minimizes the interpolation error depends mainly on the grid and the regularization strength but is almost independent of the selected HRTF set. Based on these results, the study proposes to determine the optimal SH order by minimizing the interpolation error of a reference HRTF set sampled on the sparse and irregular FBM grid. Finally, the study verifies the proposed method for estimating the optimal SH order by comparing interpolation results of irregular and equivalent regular grids, showing that the differences are small when the SH interpolation is optimally parameterized.
Das Thema Environmental Social Governance (ESG) gewinnt auch im Rückversicherungssektor aufgrund gestiegener aufsichtsrechtlicher Anforderungen an Relevanz. Dabei wurde in der Vergangenheit der Schwerpunkt auf Investments gelegt. Nun existieren immer mehr ESG-Kriterien, die das Underwriting betreffen. Welche Effekte dies auf die Branche hat, lässt sich heute noch nicht abschätzen. Klar ist, dass wir uns am Anfang einer langen Transformation befinden. ESG-Kriterien werden zukünftig vermutlich als ein weiterer Aspekt neben der versicherungstechnischen Risikobewertung berücksichtigt.