The 50 most recently published documents
Für die Defossilisierung des Heizungssektors ist die effiziente Speicherung thermischer Energie über lange Zeiträume hinweg essentiell. Das Reaktionssystem von Calciumhydroxid (Ca(OH)2), Calciumoxid (CaO) und Wasserdampf (H2O) gilt als vielversprechend für den Einsatz in thermochemischen, saisonalen Energiespeichern. Die Entwicklung effizienter Speicherreaktoren ist aufgrund der schlechten Wärmeleitfähigkeit des Speichermaterials jedoch nach wie vor eine Herausforderung, welcher bislang mit komplexen Wärmeleitstrukturen und mechanischer Fluidisierung begegnet wurde. Beide Ansätze können den Wärmeeintrag in das Speichermaterial zwar verbessern, allerdings eignen sich diese Reaktoren aufgrund ihrer Komplexität nur unzureichend für den Einsatz in Einzelgebäuden.
Grundlage dieser Arbeit ist daher ein neuartiges Konzept für einen direkt durchströmten Festbettreaktor, bei welchem das Speichermaterial in luftdurchlässigen Gitterkörben ruht. Die endotherme Beladung des Speichers erfolgt dabei über elektrische Heizstäbe im Reaktionsraum, während die Schüttung bei der exothermen Entladung mit einem Wasserdampf-Luft-Gemisch durchströmt wird.
Ziel dieser Arbeit ist die numerische Simulation des Wärmetransports im Reaktor mit Comsol Multiphysics. Durch Parametervariation wurden die wesentlichen Wärmetransportmechanismen bei der Speicherbe- und entladung identifiziert und der Einfluss geometrischer sowie materialbezogener Größen, wie bspw. dem Pelletdurchmesser oder den Abmessungen der Schüttung, analysiert.
Die Ergebnisse dieser Arbeit zeigen, dass ein effizienter Wärmeeintrag durch natürliche Konvektion in die ruhende Schüttung erfolgt, wenn die Permeabilität ebendieser hoch ist. Eine Erhöhung der Temperatur im Reaktionsraum verbessert den Wärmeeintrag ebenfalls, während jegliche Behinderungen des Fluidstroms im Reaktorinneren den Wärmeeintrag verschlechtern. Darüber hinaus beeinträchtigt eine Zunahme der Schüttungshöhe den Wärmeeintrag in diese erheblich, während die negativen Auswirkungen bei einer Verbreiterung der Schüttungskörbe – insbesondere aufgrund der erhöhten Speicherkapazität – als moderat eingestuft wurden. Es konnte gezeigt werden, dass die Strömung innerhalb der Schüttung der limitierende Faktor ist. Für einen guten Wärmeaustrag aus der Schüttung sollte diese mit dem Reaktionsgas direkt durchströmt werden, da die Wärmeübertragung von den Pellets auf das Fluid so am höchsten ist.
Mit den erstellten Simulationsmodellen wurde abschließend die konstruktive Geometrie des Reaktors ausgelegt, welcher derzeit gefertigt und anschließend experimentell vermessen wird.
One of the most significant shortcomings of the extant literature is the dearth of conceptualizations and empirical testing pertaining to entrepreneurial diversity and the underlying social identities. Accordingly, this research aims to empirically investigate the influence of entrepreneurial support at the university level on students' entrepreneurial intention from a diversity and social identity perspective. The research utilizes fsQCA (fuzzy set Qualitative Content Analysis) and a set of observable and underlying diversity factors (gender, age, previous academic performance, and parental educational attainment) to elucidate the causal structures that influence the formation of entrepreneurial intention among university students. The findings illustrate the multifaceted nature of the entrepreneurial intention formation, with first-generation status being a necessary condition for low entrepreneurial intention. The findings underscore the importance of university entrepreneurial support in the formation of entrepreneurial intention especially for younger students and first-generation students. The study contributes to the literature on entrepreneurial diversity and social identities in entrepreneurship by identifying the underlying factors that contribute to high and low entrepreneurial intention among university students.
Investigating Temperature Variations in AC Impedance with an Indigenously Developed EIS Test-Bed
(2025)
This 3rd edition compendium contains and explains essential statistical formulae in an economic context. The compendium has been enhanced with numerous additional practical examples to help readers better understand the formulas and their practical applications. The statistical formulary is presented in a practical, clear and understandable manner, as required for meaningful and relevant application in global business as well as in academic and business practice. New content includes explanations on the use of so-called dummy variables, which are useful because of their operational relevance in practice, especially in financial statistics.
This 4th edition revised and extended compendium contains and explains essential mathematical formulas within an economic context. Newly added content introduces non-linear optimization, focusing on maximizing or minimizing real problems using at least one non-linear function and continuous variables. It explains how non-linear programs may include various constraints, are influenced by the properties of the objective functions and the admissible domain, and are characterized by iterative solution processes that ideally converge to feasible, locally optimized solutions.
Diese etablierte Formelsammlung enthält und erklärt statistische Formeln, wie sie in den Wirtschaftswissenschaften und in der wirtschaftswissenschaftlichen Praxis fundamental notwendig sind. Das Verständnis der Formeln und deren praktische Anwendung werden durch nützliche Hilfen und verständliche Beispiele sinnvoll unterstützt, so dass der Kontext wirtschaftsstatistischer Formeln klar und allgemein verständlich erklärt dargestellt wird. Diese Formelsammlung ist ein unverzichtbares Tool für Studierende der Wirtschaftswissenschaften, aber auch ein nützliches Nachschlagewerk für Verantwortliche aus Wirtschaft, Politik und Lehre. In der 6. Auflage wurden die Inhalte überarbeitet und ergänzt.
Diese etablierte Formelsammlung enthält und erklärt mathematische Formeln innerhalb ökonomischer Zusammenhänge, wie sie in den Wirtschaftswissenschaften und in der wirtschaftswissenschaftlichen Praxis unbedingt notwendig sind. Das Verständnis der Formeln und deren praktische Anwendung werden durch nützliche Hilfen und erklärliche Beispiele sinnvoll unterstützt, so dass der Kontext wirtschaftsmathematischer Formeln klar und verständlich dargestellt wird. Diese Formelsammlung ist ein unverzichtbares Tool für Studierende der Wirtschaftswissenschaften, aber auch ein nützliches Nachschlagewerk für Verantwortliche aus Wirtschaft, Politik und Lehre.
Analytical Chemistry II
(2025)
This workbook takes you through the successful textbook Skoog/Holler/Crouch, Instrumentelle Analytik and is designed primarily for self-study.In five parts, the lecture content of more advanced analytical chemistry is summarized and explained using selected examples: mass spectrometry and nuclear magnetic resonance spectroscopy deal with the investigation of molecules, and numerous electroanalytical methods such as potentiometry, coulometry, amperometry and voltammetry are also covered. An overview of more specialized analytical methods includes the use of radioactive substances and various fluorescence methods, as well as methods of information acquisition in the increasingly important electrochemical and optical sensor technology and their automation. The course concludes with a summary of various principles and application methods of statistics, which are simply indispensable in the context of analytics. In order to facilitate independent learning, references to essential sections and illustrations of the textbook are made throughout the book.
In Ghana, unreliable public grid infrastructure greatly impacts rural healthcare, where diesel generators are commonly used despite their high financial and environmental costs. Photovoltaic (PV)-hybrid systems offer a sustainable alternative, but require robust, predictive control strategies to ensure reliability. This study proposes a sector-specific Model Predictive Control (MPC) approach, integrating advanced load and meteorological forecasting for optimal energy dispatch. The methodology includes a long-short-term memory (LSTM)-based load forecasting model with probabilistic Monte Carlo dropout, a customized Numerical Weather Prediction (NWP) model based on the Weather Research and Forecasting (WRF) framework, and deep learning-based All-Sky Imager (ASI) nowcasting to improve short-term solar predictions. By combining these forecasting methods into a seamless prediction framework, the proposed MPC optimizes system performance while reducing reliance on fossil fuels. This study benchmarks the MPC against a traditional rule-based dispatch system, using data collected from a rural health facility in Kologo, Ghana. Results demonstrate that predictive control greatly reduces both economic and ecological costs. Compared to rule-based dispatch, diesel generator operation and fuel consumption are reduced by up to 61.62% and 47.17%, leading to economical and ecological cost savings of up to 20.7% and 31.78%. Additionally, system reliability improves, with battery depletion events during blackouts decreasing by up to 99.42%, while wear and tear on the diesel generator and battery are reduced by up to 54.93% and 37.34%, respectively. Furthermore, hyperparameter tuning enhances MPC performance, introducing further optimization potential. These findings highlight the effectiveness of predictive control in improving energy resilience for critical healthcare applications in rural settings.
Background
Biological systems are often perceived as independent and consequently analyzed individually. In the field of omics, multiple disciplines target the study of specific types of molecules, such as genomics. The support of more data sources in these analyses is becoming more crucial for understanding the interplay of biological systems. However, this requires integration of heterogeneous knowledge, which is considered highly challenging in bioinformatics and biomedicine. Therefore, the R package Multipath was developed to model biological pathways as multilayered graphs and integrate influencing knowledge including proteins and drugs. In its previous form, Multipath generated multilayer models of BioPAX-encoded pathways and included features to integrate drug and protein information from DrugBank and UniProtKB respectively. Although the model showed remarkable utility, including further data sources ensures enriching and expanding its capabilities.
Results
In this paper, a new version Multipath 2.0 is presented. The update additionally supports the two databases KEGG Genes and OMIM, which serve as the source for gene and disease entries and interactions. Information on the interactions between the previously and newly added nodes are extracted and integrated. The Multipath 2.0 offers features to update the original multilayer model and integrate the corresponding nodes and edges into two additional layers referring to KEGG Genes and OMIM. Furthermore, the embedded nodes are inter- and intra-connected using interactions from the original and newly supported data sources.
Conclusion
The R Package Multipath is presented with the main functions that are newly developed to support the integration of the databases KEGG Genes and OMIM. The model comprises multiple information relevant to the analysis of pathway data, and offers a reproducible and simplified view of complex, intertwined systems. Through the application of such highly integrated models the inference of new knowledge becomes easier and contributes to many fields such as drug repurposing and biomarker discovery.
The growing interest toward biopolymers application in amphiphilic conditions prompts one to explore the preparation of fluorinated cellulosic materials. Cellulose (CE) and carboxymethylcellulose (CMC) are functionalized with highly fluorinated pendants, through a nucleophilic aromatic substitution on 3-pentadecafluoroheptyl-5-pentafluorophenyl-1,2,4-oxadiazole (FOX) leading to the corresponding fluorinated biopolymers CE-FOX and CMC-FOX. Structural and thermal stability confirm covalent attachment of the fluorinated moiety onto the cellulosic skeleton and highlighted an interesting 2D texture of the CMC-FOX material. Hybrid and amphiphilic features of CE-FOX and CMC-FOX, are confirmed by water and oil contact angle measurements. Applications as adsorbent material for organic contaminants from an aqueous solution are tested by previously incorporating the functional biopolymer into sodium alginate (SA) hydrogel beads. Rhodamine B (RhB) is used as a model wastewater pollutant. Fluoro-functionalization led to a three- to eightfold increase in the dye-removal efficiency of the SA-incorporated biopolymer with respect to the corresponding non-fluorinated material (from 11% to 48% for SA/CE vs SA/CE-FOX beads and from 11% to 94% for SA/CMC vs SA/CMC-FOX beads). Recyclability tests show good residual performance of SA/CMC-FOX beads after seven desorption/reuse cycles opening the way to more sustainable adsorbing processes for the removal of emerging pollutants from contaminated water.
Generative AI can considerably speed up the process of producing narrative content including different media. This may be particularly helpful for the generation of modular variations on narrative themes in hypermedia, crossmedia, or transmedia contexts, thereby enabling personalized access to the content by heterogenous target groups. We present an example where GenAI has been applied for image creation and translation of a text to multiple languages for a crossmedia edutainment project transferring IT security knowledge to vulnerable groups. GenAI still seems inadequate to produce interesting narrative text integrating dedicated educational content. AI-generated illustrations often require manual rework. However, LLM support in multilingual translations displays more intelligent solutions than expected, including the implementation of a password generation process from a narrated description.
Voice assistants (VAs) in households are becoming increasingly commonplace, with many users expressing their appreciation of the devices’ convenience. Nonetheless, a notable number of users have raised concerns that the devices are ‘always listening’, and that there is a lack of clear information from providers about the data collected and processed through their microphones. Adopting a socio-informatics research perspective, we used the living lab approach to work with users over three years to investigate their uncertainties regarding the data collected by VAs in everyday usage. Based on our findings from interviews, fieldwork, and participatory design workshops with 35 households, we developed the web tool “CheckMyVA” to support users to access and visualize their own VA data. This chapter presents the observations and findings of the three-year study by outlining the implemented features of the tool and reflecting on how its design can help improve data literacy and enable users to reflect on their long-term interactions with VAs, ultimately serving to ‘demystify’ the technology.
Unternehmensführung
(2025)
Dieses Buch führt Sie systematisch und leicht verständlich in das Thema Unternehmensführung ein. Es konzentriert sich bewusst auf die wichtigsten Fragen des Handelns als verantwortlicher Manager in der Unternehmensführung bzw. in der Bereichs- oder Abteilungsverantwortung. Dabei werden ausgewählte Probleme aus dem Management entwickelt und anschließend anhand von Praxisbeispielen erläutert. (Verlagsangaben)
Über-Setzen
(2025)
Die Beiträge in diesem Band wollen einerseits die kritische Auseinandersetzung mit dem Übersetzungsbegriff (und verwandten Konzepten) anregen, andererseits sollen Untersuchungen in den Mittelpunkt gestellt werden, die sich vertiefend mit einzelnen Aspekten von Transfer und Transformation in (digitalen) Mediendiskursen befassen.
Selenium is the third element of the group of chalcogens and is especially used in electrotechnical applications. Since many manufacturing processes use thin films of the material, knowledge of the mechanical properties is important for the detailed process layout. During the studies, the mechanical properties of trigonal selenium were determined. Therefore simulations of a uniaxial tensile test with a constant strain rate of 4.2⋅10–6/fs using molecular dynamic methods were performed. Finally a great dependency of the mechanical properties on temperature, direction and strain was observed. In particular, anisotropy in fracture behavior can be demonstrated. This can be explained by the anisotropy of trigonal selenium. In addition, a density distribution was calculated, showing that the mechanical properties are influenced by diffusion processes occurring at increased temperatures. The changes in dynamic processes point to a ductile-brittle transition.
Childhood immunization rates in many sub-Saharan African (SSA) countries have stagnated, trailing behind other global regions. This study evaluates the efficiency of childhood immunization service delivery and its environmental determinants in 36 SSA countries from 2016 to 2019. We apply data envelopment analysis (DEA) to measure technical efficiency, truncated bootstrap regression to assess influencing factors, and the Malmquist productivity index (MPI) to track productivity changes over time. Findings show that 36% of SSA countries have not met the World Health Organization’s 90% immunization target. The bias-corrected technical efficiency of immunization services is 0.895 (95% CI: 0.878–0.912). However, an MPI value of 0.715 indicates a 28.5% decline in total factor productivity, mainly due to slow technological advancements. Efficiency is positively associated with female education, governance quality, social health insurance coverage, population density, and healthcare access, while per capita GDP negatively correlates with efficiency. Despite high efficiency in some SSA countries, productivity remains hindered by technological limitations. We recommend that governments and international partners prioritize investments in technology and healthcare infrastructure to enhance productivity and improve immunization coverage.
Wissen über Wissenschaft – Ein Core Curriculum für Studierende aller Fächer (Modul 1: Gegenwart)
(2025)
Not Only in Times of Crisis: The Necessity of Contextualizing and Updating Knowledge
It is not only due to the ongoing crises that we have come to understand the necessity for diverse academic disciplines to contextualize and continuously update their bodies of knowledge in order to respond to societal demands. Furthermore, it is essential that discipline-specific knowledge, shaped by its distinct academic traditions, can also be proactively contributed to public discourse.
History and Present of the Sciences
The Core Curriculum addresses these questions in the context of university teaching, from the perspective of students, and with relevance across all disciplines. It goes beyond long-established courses that are widely offered to develop methodological competencies, guide students in writing academic papers, or provide general introductions to scholarly work. Rather than replacing these essential offerings, the Core Curriculum seeks to provide a broader framework in which such courses can ideally achieve even greater impact.
To meet this objective, the Core Curriculum consists of two components: one dedicated to the contemporary landscape of the sciences and the other to their historical development. Accordingly, the curriculum is structured with a sociological and historical orientation. Both modules are also enriched by insights from cultural and media studies.
A Flexible Syllabus
Not only the Core Curriculum as a whole, but also its two components, are designed in a modular format. Each course consists of both core and elective elements, allowing instructors from different academic traditions to adapt the seminars to their specific institutional and disciplinary contexts. The selection of materials and themes will naturally differ between engineering, education, or political science, just as it will at an art academy compared to a comprehensive university. The Core Curriculum explicitly encourages creative engagement with its provided resources. To facilitate preparation, key sources are recommended, but they can be supplemented flexibly. The syllabi of both modules have been developed with the goal of offering practical frameworks that allow for meaningful academic exploration without unduly restricting the autonomy of instructors and students.
Co-Creative Further Development
The Core Curriculum was developed by the Rhine Ruhr Center for Science Communication Research in collaboration with students at select exemplary universities. Ideally, it will continue to evolve in practice as it is implemented locally. The sciences themselves are in constant transformation, and this ongoing change should not only be reflected in the curriculum but also actively negotiated within it.
At its core, the Core Curriculum is committed to a "spirit" of praxeological reflection: it is designed to support both students and instructors in critically engaging with the multiplicity and complexity of the sciences, as well as their respective histories.
Shared Responsibility for Science in Higher Education
However, this goal is not an end in itself. The underlying assumption of the Core Curriculum is that students across all disciplines in Germany are being educated for a society in which an increasing number of issues, opportunities, and conflicts are shaped by scientific knowledge.
Engaging at an early stage in a foundational and conceptually rich examination of both the origins and future trajectories of scientific knowledge can benefit students from all fields. This engagement does not begin only after graduation; rather, the Core Curriculum empowers students from the undergraduate level onward to critically reflect on their own academic environment, questioning why certain academic practices prevail at their institution—and whether they might actively participate in shaping alternative approaches.
This dataset accompanies the study “Universal Metrics to Characterize the Performance of Imaging 3D Measurement Systems with a Focus on Static Indoor Scenes” and provides all measurement data, processing scripts, and evaluation code necessary to reproduce the results. It includes raw and processed point cloud data from six state-of-the-art 3D measurement systems, captured under standardized conditions. Additionally, the dataset contains high-speed sensor measurements of the cameras’ active illumination, offering insights into their optical emission characteristics. The key performance metrics—covering precision, accuracy, trueness, surface texture, and the Energy-Density-Weighted Depth Precision Index (EPI)—are summarized in a PowerPoint presentation with plots for easy comparison. By making this dataset publicly available, we aim to support further research, benchmarking, and the development of standardized evaluation methodologies for 3D imaging systems.
This repository includes the following datasets:
Own Dataset: A collection of 394 with source code typosquatting packages we have collected based on SonaType, Phylum.io and Snyk listings.
Backstabbers Knife Collection: A snapshot of Backstabbers Knife Collection during our analysis for reproduction purposes
MalOSS: A snapshot of the MalOSS dataset during our analysis for reproduction purposes.
Source code: The source code of our programs and algorithms, mainly the Random Forest models, and the Extended Damerau-Levenshtein MetricHowever, the source code of the packages provided by MalOSS and Backstabbers Knife Collection must be retrieved by the corresponding owner/maintainer.
A database of 98 climate-relevant social protection programs in emerging and developing economies
(2024)
The database maps the integration of climate considerations in social protection programs in emerging and developing economies. Using a mixed-methods approach, we identified 98 climate-relevant social protection programs and collected data on over 70 variables related to their scope and climate relevance at policy, design, and implementation level.
The database might periodically be revised to improve the data points for each program (including referencing, coding, etc.). We do not intend to add new programs to it.
Please ensure to download and cite the latest version of the database available in this page for the most up-to-date and precise data.
We encourage researchers and practitioners to use the database in building a more comprehensive understanding of climate-relevant social protection programs worldwide.
Hochschulen für Angewandte Wissenschaften (HAW) übernehmen in Deutschland etwa die Hälfte der Informatikausbildung im Bereich Bachelor und Master. Neu ist, dass auch Doktortitel in Informatik an einigen HAW erworben werden können. Dies eröffnet für Informatik neue Perspektiven und wirft Fragestellungen auf. Neben den Charakteristika einer Promotion im Fach Informatik an einer HAW sind dies beispielsweise das Qualifikationsprofil von Promovierten und ihre Karriereperspektiven, Kooperationsformen mit externen Anwendungspartnern als auch die Frage, wie Potenziale im Sinne der Informatik gehoben werden können. Dieser Beitrag liefert Grundlagen zu dieser Diskussion. Der Hintergrund des eigenständigen Promotionsrechts von HAW wird besprochen, es werden verschiedene Modelle der Umsetzung anhand von Beispielen aus Hessen, Nordrhein-Westfalen und Rheinland-Pfalz vorgestellt sowie erste Erfahrungen mit dem eigenständigen Promotionsrecht berichtet.
This contribution explores the opportunities and challenges of digitalizing cultural heritage, using the Digitalization of Cultural Heritage project as a case study. The project, a collaboration among universities from multiple countries, focuses on creating 3D models of historical artifacts, exemplified by the 3D modelling of Roman-period fragments using photogrammetry. The paper discusses the broader implications of digitalization with a particular focus on the use of AI technologies, including its potential to enhance education, accessibility, artifact preservation, and cultural tourism. It also addresses the technical and ethical challenges involved, emphasizing the need for ongoing innovation and interdisciplinary collaboration to maximize the benefits of digital cultural preservation.This contribution explores the opportunities and challenges of digitalizing cultural heritage, using the Digitalization of Cultural Heritage project as a case study. The project, a collaboration among universities from multiple countries, focuses on creating 3D models of historical artifacts, exemplified by the 3D modelling of Roman-period fragments using photogrammetry. The paper discusses the broader implications of digitalization with a particular focus on the use of AI technologies, including its potential to enhance education, accessibility, artifact preservation, and cultural tourism. It also addresses the technical and ethical challenges involved, emphasizing the need for ongoing innovation and interdisciplinary collaboration to maximize the benefits of digital cultural preservation.
Das Interesse an Wissenschaft und Forschung reicht heute weit über die Mauern von Universitäten, Forschungseinrichtungen oder Instituten hinaus. Bürger*innen wollenmitdiskutieren, welche Themen und Probleme erforscht werden sollen, möchten mitforschen sowie gemeinsam mit Expert*innen Ergebnisse auswerten und diskutieren. Dafürsind zahlreiche Beteiligungsformate denkbar. Beispielsweise entwickeln Bürger*innen im Rahmen von Citizen Science gemeinsam mit Wissenschaftler*innen eigene Forschungsfragen, wägen Methoden ab und führen selbst wissenschaftliche Erhebungen durch. In Reallaboren und Experimentierräumen kooperieren Akteur*innen aus Wissenschaft, Zivilgesellschaft, Verwaltung und Wirtschaft, um Antworten auf konkrete Herausforderungen vor Ort zu entwickeln und im experimentellen Umfeld zu erproben. Ebenso werden immer stärker die Perspektiven und Meinungen zivilgesellschaftlicher Organisationen Teil politischer Beratungsgremien und -foren, um dort über Forschungsprogramme mitzuentscheiden.
Der vorliegende Methodenleitfaden soll als Handreichung sowohl für Projektverantwortliche, Projektmitarbeitende als auch Citizen Scientists dienen, die sich zum ersten Mal oder erneut mit der Initiierung, Planung, Durchführung und Evaluation eines Citizen-Science-Projekts befassen. Dabei stehen zentralre Fragen im Fokus: Welche Schrittemüssen bedacht werden? Welche Strukturen geschaffen und Prozesse aufgebaut werden? Welche unterschiedlichen Möglichkeiten zur Einbindung von Bürger*innen gibt es? Wie kann die Motivation von Bürger*innen während des gesamten Projekts aufrechterhalten werden? Welche bürokratischen Hürden können wie angegangen werden?
torchtime
(2022)
The aim of torchtime is to apply PyTorch to the time series domain. By supporting PyTorch, torchtime follows the same philosophy of providing strong GPU acceleration, having a focus on trainable features through the autograd system, and having consistent style (tensor names and dimension names). Therefore, it is primarily a machine learning library and not a general signal processing library. The benefits of PyTorch can be seen in torchtime through having all the computations be through PyTorch operations, which makes it easy to use and feel like a natural extension.
Childhood immunization rates in many sub-Saharan African (SSA) countries have stagnated, trailing behind other global regions. This study evaluates the efficiency of childhood immunization service delivery and its environmental determinants in 36 SSA countries from 2016 to 2019. We apply data envelopment analysis (DEA) to measure technical efficiency, truncated bootstrap regression to assess influencing factors, and the Malmquist productivity index (MPI) to track productivity changes over time. Findings show that 36% of SSA countries have not met the World Health Organization’s 90% immunization target. The bias-corrected technical efficiency of immunization services is 0.895 (95% CI: 0.878–0.912). However, an MPI value of 0.715 indicates a 28.5% decline in total factor productivity, mainly due to slow technological advancements. Efficiency is positively associated with female education, governance quality, social health insurance coverage, population density, and healthcare access, while per capita GDP negatively correlates with efficiency. Despite high efficiency in some SSA countries, productivity remains hindered by technological limitations. We recommend that governments and international partners prioritize investments in technology and healthcare infrastructure to enhance productivity and improve immunization coverage.
Energetic materials (EMs) are compounds or mixtures of substances that contain both fuel and an oxidizer. When these materials react, they release thermal energy and produce a large amount of gas. The initiation of these substances can be triggered by mechanical, thermal, electrostatic, or optical influence. A distinction is made between materials that are capable of exploding and those that are hazardous due to their potential to explode [1].
EMs are not only used for military purposes, but also for civilian applications, such as in airbags, fireworks or explosives in mining. It has been a long way from the initial invention of the first explosives to their widespread use today. In 220 B.C., the Chinese accidentally discovered black powder. Centuries later, in the 13th and 14th centuries, the monk Roger Bacon and the German Berthold Schwarz researched the explosive for the first time in Europe. The military use of black powder began at this time. In 1846, nitroglycerine was discovered by Ascanio Sobrero. Alfred Nobel reduced the sensitivity of the highly sensitive nitroglycerine, thus making it possible to use the substance. The so-called dynamite was developed. Alfred Nobel also played an important role in the progress in the history of initial substances. His findings made it possible to reliably initiate dynamite by replacing black powder with mercury fulminate. This was replaced at the beginning of the 20th century by lead azide, which is still used today [2, 3].
In the following years, as demand increased, other explosives were developed and synthesised, many of which are still in use today. This led to the development of trinitrotoluene, triaminotrinitrobenzene and hexogen (RDX), for example. The focus in the development of energetic materials changed over time. In addition to reliability, the safe handling of the substances was often at the centre of research when it came to their commercial/military use. During the Second World War, for example, the use of polymer-bound explosives was favoured, resulting in the production of Semtex, a mixture of nitropenta (PETN) and RDX bound with styrene-butadiene rubber. Today, the focus of the development of energetic materials is on environmentally friendly research into materials in terms of sustainability and the improvement of existing properties (e.g. shorter initiation times for special military applications).
Yeast complementation assays provide limited informationon functional features of K+ channels
(2025)
We investigate to what extent yeast complementation assays, which in principle can provide large amounts of training data for machine learning models, yield quantitative correlations between growth rescue and single channel recordings. If this were the case, yeast complementation results could be used as surrogate data for machine learning-based channel design. Therefore, we mutated position L94 at the cavity entry of the model K+ channel KcvPBCV1 to all proteinogenic amino acids. The function of the WT channel and its mutants was investigated by reconstituting them in planar lipid bilayers and by their ability to rescue the growth of a yeast strain deficient in K+ uptake. The single channel data show a distinct effect of mutations in this critical position on unitary conductance and open probability, with no apparent causal relationship between the two functional parameters. We also found that even conservative amino acid replacements can alter the unitary conductance and/or open probability and that most functional changes show no systematic relationship with the physicochemical nature of the amino acids. This emphasizes that the functional influence of an amino acid on channel function cannot be reduced to a single chemical property. Mutual comparison of single channel data and yeast complementation results exhibit only a partial correlation between their electrical parameters and their potency of rescuing growth. Hence complementation data alone are not sufficient for enabling functional channel design; they need to be complemented by additional parameters like the number of channels in the plasma membrane.
Diagnosis and prognosis of intermittent faults, in general, is difficult as it is unknown when and for how long intermittent faults will reappear. This paper addresses the case of parametric incipient faults and simultaneously occurring intermittent faults with a magnitude that increases over time so that they may reach a failure alarm threshold and may eventually lead to a component or even a system failure.
The presented Bond Graph-based approach consists of two parts. First, a Diagnostic Bond Graph (DBG) is developed offline for an online diagnosis of intermittent faults by means of Analytical Redundancy Relations (ARRs). Due to the magnitude of intermittent faults increasing with time, the time evolutions of ARRs indicate a degradation trend. In a second, data-based, part, values of this trend over a moving time window stored in a buffer are extrapolated concurrently to the monitoring and to the fault detection and isolation (FDI) part in a repeated failure prognosis resulting in a sequence of Remaining Useful Life (RUL) estimates. A case study considers a small switched electronic circuit.
Die vorliegende Masterarbeit untersucht die Funktion von TikTok als Suchmaschine und analysiert, welche Themen sich in den Suchvorschlägen der Plattform widerspiegeln. Ausgehend von der These, dass sich die Suchvorschläge aus tatsächlich getätigten Suchanfragen der Nutzer:innen ergeben, wird der Frage nachgegangen, welche Rückschlüsse sich aus diesen Vorschlägen auf Nutzer:inneninteressen und Plattformstrategien ziehen lassen. Der theoretische Teil der Arbeit gibt einen fundierten Überblick über relevante Konzepte aus der Informationswissenschaft und Suchmaschinenforschung. Dabei werden die Besonderheiten von TikTok als Plattform und Suchmaschine herausgearbeitet und im Kontrast zu klassischen Websuchmaschinen beleuchtet. Methodisch basiert die Untersuchung auf einer explorativen Analyse von 10.341 Suchvorschlägen mit 1.388 einzigartigen Begriffen, die über einen Zeitraum von zehn Wochen mithilfe einer TikTok-API erhoben wurden. Für die qualitative Auswertung wurde induktiv ein Kategoriensystem mit zwölf Oberkategorien entwickelt. Die Ergebnisse zeigen, dass die Nutzer:inneninteressen auf TikTok stark von Aktualität, Trendthemen und emotionalen Aspekten geprägt sind. Gleichzeitig gibt es Hinweise auf eine aktive Plattformsteuerung durch Hervorhebung oder Zurückhaltung bestimmter Themen.
In 2020, around 44% of natural gas in Germany was used in combined heat and power as well as in combined cycle gas turbines plants. As district heating will play an important role in future heating planning, the retrofit of these plants to hydrogen is a viable option. This paper analyzes a typical combined cycle power plant, including its balance of plant under consideration of different hydrogen blends. We show that retrofits are limited by the gas turbines in many cases. For instance, the preheater in the fuel gas system must be dimensioned higher than with natural gas. While pressure losses are very low, materials could be a problem due to higher volume flows. Additionally, the higher combustion temperatures in the gas turbine can compensate for possible efficiency losses in the Heat Recovery System Generator (HRSG) and steam turbine making this a suitable approach for electricity-led plants. However, for heat-led plants this leads to a reduction in the district heating output. Therefore, the performance of the HRSG must be considered as a limiting factor for heat-driven plants and the change in flue gas must be analyzed. Currently, hydrogen blends of 20–40 vol.-% appear feasible without major adjustments. The water content in the exhaust gas can also lead to problems in the HRSG and flue gas aftertreatment due to changes in the dew point. For higher hydrogen blends, a plant specific analysis is recommended.
Development of Open Educational Resources for Renewable Energy and the Energy Transition Process
(2021)
Object-oriented programming is a wonderful way to make programming of huge real life tasks much easier than by using procedural languages. In order to teach those ideas to students, it is important to find a good task that shows the advantages of OOprogramming very naturally. This paper gives an example, the game Battleship, which seems to work excellent for teaching the OO ideas (using Java, [1], [2], [3], [4]). A three-step task is presented for how to teach OO-programming using just one example suitable to convey many of the OO ideas. Observations are given at the end and conclusions about how the whole teaching course worked out.
