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Die Bachs sind die größte Musiker-Dynastie aller Zeiten. Die Wurzeln dieser berühmten Familie und ihre musikalischen Anfänge liegen im Gothaer Land. Hier spielte am Anfang des 17. Jahrhunderts der Wechmarer Müller Vitus Bach auf dem Cythringen und wurde zum Stammvater des musikalischen Bachgeschlechts. Seine Söhne und Enkel zogen musizierend durch das Land und machten sich überall in Thüringen einen Namen als begnadete Musiker. Über Generationen hinweg schallte der Ruf der Bachs in die Welt, blieb aber auch weiterhin unmittelbar mit dem Gothaer Land verbunden. Johann Sebastian Bach erlernte in Ohrdruf das Orgelspiel und brachte Ostern 1717 in der Gothaer Schlosskirche seine erste Passion zur Aufführung. Aber auch abseits des wohl weltweit bekanntesten Bachs waren über zwei Jahrhunderte hindurch zahlreiche Mitglieder der Familie in diesem Raum als Kantoren, Organisten, Lehrer und Geistliche tätig. Der Band widmet sich in 22 Beiträgen dem Leben und Wirken dieser musikalischen Großfamilie und gibt zugleich Einblicke in das Bach-Erbe und die Bach-Traditionen des Gothaer Landes.
Liquid deposition modeling is an energy-efficient, additive manufacturing process for pasty materials. Physical material properties were determined for a water-based paste consisting of the binder carboxymethyl cellulose and wood flour. A continuously operating dual screw extruder was developed, which was used to manufacture a table frame with a height of 18 cm.
Based on a real-world application in the semiconductor industry, this article models and discusses a hybrid flow shop problem with time dependencies and priority constraints. The analyzed problem considers a production where a large number of heterogeneous jobs are processed by a number of machines. The route that each job has to follow depends upon its type, and, in addition, some machines require that a number of jobs are combined in batches before starting their processing. The hybrid flow model is also subject to a global priority rule and a “same setup” rule. The primary goal of this study was to find a solution set (permutation of jobs) that minimizes the production makespan. While simulation models are frequently employed to model these time-dependent flow shop systems, an optimization component is needed in order to generate high-quality solution sets. In this study, a novel algorithm is proposed to deal with the complexity of the underlying system. Our algorithm combines biased-randomization techniques with a discrete-event heuristic, which allows us to model dependencies caused by batching and different paths of jobs efficiently in a near-natural way. As shown in a series of numerical experiments, the proposed simulation-optimization algorithm can find solutions that significantly outperform those provided by employing state-of-the-art simulation software.
A novel approach to consider triaxial tensile stresses within the framework of a failure criterion
(2022)
For use in micromechanical simulations of continuous fiber reinforced polymers, a more general form of the paraboloid failure criterion by Stassi‐D'Alia for matrix failure was developed with explicit consideration of the hydrostatic tension strength. Regarding polymers, limits for hydrostatic tensile strength based on isotropic linear elasticity could be derived. The comparison of the newly developed extended paraboloid criterion with experimental data for yielding as well as for material separation (fracture) shows good agreement.
The purpose of this article is to revise the literature on how theories have been utilized in investigating third-parties (for example, Non-Governmental Organizations, certifying organizations, among others) in Sustainable Supply Chain Management. Based on that, we derive future research directions. For revising the literature in a structured manner, the articles use the systematic literature review as the method of choice. Only half of the identified articles utilize theories for investigating third-parties in Sustainable Supply Chain Management. In addition, major theories are overweighed. This predomination leads to influencing the conceptualization of third-parties in Sustainable Supply Chain Management. Future research opportunities exist in broadening the utilization of theories and methods applied in the field, investing in under-explored aspects and broadening the scope of testing and building frameworks. Based on the synthesizing, propositions supplement future research directions. The novelty of this article lies in its investigation of how theories have been used in investigating and conceptualizing third-parties in Sustainable Supply Chain Management. By that, it contributes with a state-of-the-art view on the important topic of sustainability and how third-parties could solve sustainability challenges. With that, the article is a first attempt and step for extending the academic literature and practice with rethinking classic ways of managing sustainability and utilize out of the box ideas.
ALADIN – Generator für Aufgaben und Lösung(shilf)en aus der Informatik und angrenzenden Disziplinen
(2022)
Alternative Leistungskennzahlen (APM) in der Finanzberichterstattung österreichischer Emittenten
(2022)
Structures made of the thermoplastic polymer polyether ether ketone (PEEK) are widely used in dynamically-loaded applications due to their high-temperature resistance and high mechanical properties. To design these dynamic applications, in addition to the well-known stiffness and strength properties the vibration-damping properties at the given frequencies are required. Depending on the application, frequencies from a few hertz to the ultrasonic range are of interest here. To characterize the frequency-dependent behavior, an experimental approach was chosen and applied to a sample polymer PEEK. The test setup consists of a piezoelectrically driven base excitation of the polymeric specimen and the non-contact measurement of the velocity as well as the surface temperature. The beam’s bending vibrations were analyzed by means of the Timoshenko theory to determine the polymer’s storage modulus. The mechanical loss factor was calculated using the half-power bandwidth method. For PEEK and a considered frequency range of 1 kHz to 16 kHz, a storage modulus between 3.9 GPa and 4.2 GPa and a loss factor between 9 × 10−3 and 17 × 10−3 were determined. For the used experimental parameters, the resulting mechanical properties were not essentially influenced by the amplitude of excitation, the duration of excitation, or thermal degrad.ation due to self-heating, but rather slightly by the clamping force within the fixation area.
Analgesic drug use of recreational and competitive badminton players: Starting points for prevention
(2021)
Analysis of a Film Forming Process through Coupled Image Correlation and Infrared Thermography
(2022)
The aim of the present investigation was to determine the dependence of the material and process parameters of the bending process of thermoplastic films. In this context, parameter combinations leading to high resulting forming ratios were identified. To measure the relevant parameters within the hot bending process, a coupled evaluation of infrared thermography (IRT) and deformation measurement using digital image correlation (DIC) was performed. The coupled measurement enables the identification of the actual mechanically stressed bending area of the film as a result of the bending process. This allows for the specification of the local forming temperatures required for the desired forming ratios. Furthermore, the mechanical and thermal strain along the defined measuring sections and their deviation in individual tests as well as the effect of thermal strain on process control on a larger scale were determined. Based on the results, a process window was defined for the film materials investigated, which will serve as a starting point for future efforts to develop a continuous manufacturing process.
This paper provides a critical reading of Janek Wasserman’s The Marginal Revolutionaries: How Austrian Economists Fought the War of Ideas. Wasserman depicts the evolution of the Austrian School from the 1860s until today, a particularly illuminating narrative for the readers of this journal. The breadth of portrayed economists, their cultural embeddedness in Austrian and US contexts, and the complexity of configurations across the school’s generations create a rich and readable story. The last third of the book suffers from allegations about the ideological agenda and institutional power of the Austrian economists which sometimes lack sufficient substantiation. The paper indicates how both in their theorizing and in their political activities, the Austrian economists can be seen as reformers instead of revolutionaries, and as constitutionalists instead of anti-democrats. Despite these disagreements, Wasserman’s portrayals evoke largely fair and challenging impulses both to scholars working in the Austrian research program and to those interested in the Austrian School’s long history, regardless of one’s ideological positions.
Hypotrochoidal profile contours have been produced in industrial applications in recent years using two-spindle processes, and they are considered effective high-quality solutions for form-fit shaft and hub connections. This study mainly concerns analytical approaches to determine the stresses and deformations in hypotrochoidal profile shafts due to pure bending loads. The formulation was developed according to bending principles using the mathematical theory of elasticity and conformal mappings. The loading was further used to investigate the rotating bending behaviour. The stress factors for the classical calculation of maximum bending stresses were also determined for all those profiles presented and compiled in the German standard DIN3689-1 for practical applications. The results were also compared with the corresponding numerical and experimental results, and very good agreement was observed. Additionally, based on previous work, the stress factor was determined for the case of torsional loading to calculate the maximum torsional stresses in the standardised profiles, and the results are listed in a table. This study contributes to the further refinement of the current DIN3689 standard.
This paper presents an analytical method for determining the bending stresses and deformations in prismatic, noncircular profile shafts with trochoidal cross sections. The so-called higher trochoids can be used as form-fit shaft-hub connections. Hybrid (mixed) higher trochoids (M-profiles) were developed for the special application as a profile contour for the form-fit shaft and hub connections in an earlier work by the author. M-profiles combine the advantages of the two standardised polygonal and spline contours, which are used as shaft-hub connections for the transmission of high torques. In this study, the geometric and mechanical properties of the higher hybrid trochoids were investigated using complex functions to simplify the calculations. The pure bending stress and shaft deflection were determined for M-profiles using bending theory based on the theory of mathematical elasticity. The loading cases consisted of static and rotating bends. Analytical, numerical, and experimental results agreed well. The calculation formulas developed in this work enable reliable and low-cost dimensioning with regard to the stresses and elastic deformations of profile shafts subjected to bending loads.
Abstract: Die Automobilindustrie befindet sich seit Jahren im Ausnahmezustand, da der Wechsel von einer Einheitsantriebsart hin zu einem Mix an Antriebsarten parallel zu globalen Krisen bewältigt werden muss. Der vorliegende Beitrag liefert dazu beispielhafte Betrachtungen zur indikativen Bewertung der gegensätzlichen Produktionsstrategien Mix- oder sortenreiner Produktion von Fahrzeugen mit alternativen und konventionellen Antrieben. Die Erkenntnisse können genutzt werden, um Modelle zur Wahl der richtigen Produktionsstrategien abzuleiten.
Für viele Menschen ist das Pferd ein wichtiger Begleiter in der Freizeit, im Profisport oder auch in der Landwirtschaft. Gerade aber für die prozentual am häufigsten vertretenen Freizeitreiter wird es immer schwieriger, geeignete Anbieter für die Pflege und Bearbeitung der Hufe und das Training zu finden. Sei es die stetig steigende Variabilität von Hufbearbeitungszuständen wie z.B. Barhuf, Eisen- oder Aluminiumbeschlag oder Kunststoffeisen bei immer weniger verfügbaren und fachgerecht ausgebildeten Schmieden oder die Vielzahl an Trainingsmöglichkeiten wie z.B. Klassisch-Barock, Western, Alt-Californisch, Vaquero, Englisch oder Natural Horsemanship. Bei dieser kontinuierlich steigenden Anzahl an Varianten und Strömungen, aber auch schwieriger Dienstleistungssituation ist es wichtig, gerade Freizeitreitern eine sichere und verlässliche, aber auch qualitativ hochwertige Betreuung zur Verfügung zu stellen. Im Rahmen dieses Businessplanes soll dabei ein kooperatives Angebot aus Hufpflege und Natural Horsemanship Training in seinen Vor- und Nachteilen erörtert werden.
Certifying Fully Dynamic Algorithms for Recognition and Hamiltonicity of Threshold and Chain Graphs
(2023)
Solving problems on graphs dynamically calls for algorithms to function under repeated modifications to the graph and to be more efficient than solving the problem for the whole graph from scratch after each modification. Dynamic algorithms have been considered for several graph properties, for example connectivity, shortest paths and graph recognition. In this paper we present fully dynamic algorithms for the recognition of threshold graphs and chain graphs, which are optimal in the sense that the costs per modification are linear in the number of modified edges. Furthermore, our algorithms also consider the addition and deletion of sets of vertices as well as edges. In the negative case, i.e., where the graph is not a threshold graph or chain graph anymore, our algorithms return a certificate of constant size. Additionally, we present optimal fully dynamic algorithms for the Hamiltonian cycle problem and the Hamiltonian path problem on threshold and chain graphs which return a vertex cutset as certificate for the non-existence of such a path or cycle in the negative case.
Abstract: Duplex steels are used for applications that require high strength and ductility combined with good corrosion resistance. An economical welding technology to handle these steels is achieved by combining the MIG and TIG arc processes. The aim is to improve welding speed and quality by utilizing a TIG-MIG hybrid welding process to join 1.4462 duplex steel with a thickness of 2 mm. The interaction between the two arcs, caused by the blowing effect, is an enormous challenge that can be counteracted with a defined torch position and current modulation. For this purpose, a variation of the MIG (pulsed and AC pulsed arc) and TIG process (AC and pulsed DC) took place. The influence of electrical parameters on process stability and material transfer was investigated. For analysis, an evaluation of high-speed recordings (5000 frames per second) and synchronized measured current/voltage curves (200 kHz) is carried out. Based on a number of selected specimens, a welding procedure test according to ISO 15614-1 is performed to determine the welding seam quality. The test includes the characterization by tensile and hardness testing and macroscopic and microscopic examination. Additionally, the specimens are examined according to ISO 5817.
Conceptual Approach to an AI-Based Adaptive Study Support System for Individualized Higher Education
(2023)
In the context of the digital transformation, the targeted implementation of AI-based or AI-supported technologies in "teaching & learning" as well as "administration & service" holds considerable potential for organizational change and quality enhancement for higher education institutions. The use of AI in higher education teaching and services lags behind the level in research. Therefore, holistic solutions must be planned and implemented in unity of teaching and research for the AI-based support of the stakeholders’ inclusive administration, the further development or the establishment of new digital study programs and offers as well as the prospective qualification of university staff in the field of AI. The solutions must be analyzed, systematized, and structured to generate a conceptual approach via an integrated architecture with adaptive services.
This paper is an evolution of the concept presented at the Learning Ideas Conference 2022 and includes, in addition to explanations of the current state of the arts, the presentation of a systems-oriented approach for AI in higher education as well as the conception of the student lifecycle management at the author’s university. The paper ends with the presentation of a concept regarding a decision support system for individualized studying.
Abstract
This article presents a cost-effective ultraviolet-ozone cleaner (UV/O3 Cleaner) for surface pre-treatment of substrates in the field of semiconductor technology. The cleaner consists of two chambers, the upper one contains the electronics, including the time counter. The lower chamber contains the two UV sterilisation lamps and a UV reflector of anodized aluminium, which confines the area of high Ozone concentration in the area of interest. The device is successfully used for surface cleaning and modification of different materials. To this end, the two important wavelengths 253.7 nm (excitation of organic residues) and 184.9 nm (production of ozone from the atmospheric environment as a strong oxidant) were first detected. The effectiveness of UV/O3 cleaning is demonstrated by improving the properties of indium tin oxide (ITO) for OLED fabrication. The contact angle of water to ITO could be reduced from 90° to 3° and for diiodomethane, it was reduced from 55° to 31° within the 10 min of irradiation. This greatly improved wettability for polar and non-polar liquids can increase the flexibility in further process control. In addition, an improvement in wettability is characterized by measuring the contact angles for titanium dioxide (TiO2) and polydimethylsiloxane (PDMS). The contact angle of water to TiO2 decreased from 70° to 10°, and that of diiodomethane to TiO2 from 54° to 31°. The wettability of PDMS was also greatly increased. Here, the contact angle of water was reduced from 109° to 24° and the contact angle to diiodomethane from 89° to 49°.
Article Highlights
We report a cost-effective dry-cleaning device for surface cleaning and modification based on ultraviolet-ozone irradiation.
Contact angle measurements show an increase of wettability for different materials due to surface modification.
The UVO3 pre-treatment improves layer formation and optoelectrical properties of OLEDs.
The book is the first of four volumes on data science and artificial intelligence. This first volume covers fundamentals of data science: an introduction to Python programming, software libraries for data management, techniques for working with big data. It contains many exercises and projects with real-world data.
The book is the second of four volumes on data science and artificial intelligence. This second volume covers data visualization tool and techniques as well as fundamentals of supervised machine learning: linear regression, artificial neural networks, support-vector machines, decision trees, ensemble methods and more.
Der General
(2022)
Models of artificial root canals are used in several fields of endodontic investigations and pre-clinical endodontic training. They allow the physical testing of dental treatments, the operating of instruments used and the interaction between these instruments and the tissues. Currently, a large number of different artificial root canal models exist whose geometry is created either on the basis of selected natural root canal systems or to represent individual geometrical properties. Currently, only a few geometric properties such as the root canal curvature or the endodontic working width are taken into consideration when generating these models. To improve the representational capability of the artificial root canal models, the aim of the current study is therefore to generate an artificial root canal based on the statistical evaluation of selected natural root canals. Here, the approach introduced by Kucher for determining the geometry of a root canal model is used, which is based on the measurement and statistical evaluation of the root canal center line’s curvatures and their cross-sectional dimensions. Using the example of unbranched distal root canals of mandibular molars (n = 29), an artificial root canal model representing the mean length, curvature, torsion and cross-sectional dimensions of these teeth could be derived.
Development and Characterization of a Dispersion-Encoded Method for Low-Coherence Interferometry
(2022)
This Open Access book discusses an extension to low-coherence interferometry by dispersion-encoding. The approach is theoretically designed and implemented for applications such as surface profilometry, polymeric cross-linking estimation and the determination of thin-film layer thicknesses. During a characterization, it was shown that an axial measurement range of 79.91 µm with an axial resolution of 0.1 nm is achievable. Simultaneously, profiles of up to 1.5 mm in length were obtained in a scan-free manner. This marked a significant improvement in relation to the state-of-the-art in terms of dynamic range. Also, the axial and lateral measurement range were decoupled partially while functional parameters such as surface roughness were estimated. The characterization of the degree of polymeric cross-linking was performed as a function of the refractive index. It was acquired in a spatially-resolved manner with a resolution of 3.36 x 10-5. This was achieved by the development of a novel mathematical analysis approach.
Sometimes cranioplasty is necessary to reconstruct skull bone defects after a neurosurgical operation. If an autologous bone is unavailable, alloplastic materials are used. The standard technical approach for the fabrication of cranial implants is based on 3D imaging by computed tomography using the defect and the contralateral site. A new approach uses 3D surface scans, which accurately replicate the curvature of the removed bone flap. For this purpose, the removed bone flap is scanned intraoperatively and digitized accordingly. When using a design procedure developed for this purpose creating a patient-specific implant for each bone flap shape in short time is possible. The designed skull implants have complex free-form surfaces analogous to the curvature of the skull, which is why additive manufacturing is the ideal manufacturing technology here. In this study, we will describe the intraoperative procedure for the acquisition of scanned data and its further processing up to the creation of the implant.
Zusammenfassung
Hintergrund
Die COVID-19(„coronavirus disease 2019“)-Pandemie hat die Ad-hoc-Digitalisierung an Hochschulen vorangetrieben. Zugleich stand die digitale Hochschullehre vor der Herausforderung der Ausgestaltung der Lehre im Zusammenhang mit den vorbestehenden Ressourcen, der digitalen und didaktischen Kompetenzen sowie der zur Verfügung stehenden technischen Infrastruktur.
Ziel der Arbeit/Fragestellung
Das Ziel der Umfrage war die Einschätzung der digitalen Lehre, die die Präsenzlehre infolge der COVID-19-Pandemie zum großen Teil bzw. gänzlich ersetzt hat, aus der Perspektive der Lehrenden in Public Health, Medizin und Pflege.
Material und Methode
Die Querschnitterhebung fand online von Juni bis August 2020 statt und die Daten wurden über www.soscisurvey.de erhoben. Die schriftliche Befragung wurde unter Mitgliedern der Deutschen Gesellschaft für Public Health (DGPH) und des Ausschusses Digitalisierung der Gesellschaft für medizinische Ausbildung (GMA) und der Sektionen Bildung und Beratung der Deutschen Gesellschaft für Pflegewissenschaft (DGP) sowie der Arbeitsgruppe Lehre der Deutschen Gesellschaft für Medizinische Soziologie (DGMS) durchgeführt (n = 100).
Ergebnisse
Bei der Nutzung der digitalen Technologien in den Veranstaltungen rangieren auf der obersten Stelle Präsentationstools, gefolgt von Lernmanagementsystemen, Videoangeboten sowie digitalen Texten. Die Teilnehmenden geben hinsichtlich der Nutzung unterschiedliche (Konferenz‑)Tools an. Das Erstellen von Lehrvideos bejahen 53 % der Befragten, Abstimmungstools) werden bis 50 % als unbekannt genannt. Als Herausforderungen werden digitale Infrastruktur der Hochschulen, fehlende didaktische Beratung/Unterstützung sowie rechtliche Fragen (Nutzungsrechte, Datenschutz) angegeben.
Schlussfolgerung
Neue Technologie werden vorwiegend für Wissenserwerb, Wissensvermittlung genutzt, selten zur Aktivierung von Studierenden und zur Gestaltung kollaborativer Lehr- und Lernarrangements sowie Neugestaltung von Lernaufgaben und Lernprozessen (individualisiertes Lernen). Welche der aktuell erprobten digitalen Lehr- und Lernformate zukünftig in der Hochschullehre zunehmend eingesetzt werden, hängt von vielen Faktoren ab, u. a. von digitaler Kompetenz sowie der Bereitschaft der Lehrenden und Lernenden die digitale Lernkultur mitzugestalten.
Dissipation energy based parameter identification of anisotropic linear viscoelastic composites
(2020)
The current work presents a relaxation analysis based procedure to identify effective material parameters of the multiaxial generalized Maxwell model (GMM) by a numerical homogenization of the microscopic dissipation energy density for anisotropic linear viscoelastic composites. The employed GMM enables the derivation of a thermodynamically consistent constitutive law and a function of the dissipation energy density for direction‐dependent viscoelastic materials. The identity of this energy function to the microstructure's homogenized dissipation energy density is utilized for the identification of effective relaxation times. Furthermore, the identified relaxation times enable a simple determination of the remaining stiffness parameters. Finally, the presented procedure is demonstrated and evaluated for a randomly endless fibre‐reinforced plastic with a polymer matrix exhibiting a significant viscoelastic behaviour.
Effect of acoustic excitation on fiber-reinforced polypropylene and the influence on melt viscosity
(2021)
The paper describes a novel technological approach to influencing the rheological properties of thermoplastic materials exposed to acoustic energy. The flow behavior of polypropylene with different mass percentages of glass fibers is investigated in a parallel plate rheometer under high-frequency longitudinal excitation. The influence of oscillation frequency on the melt viscosity is explained by means of shear thinning criteria. The dependence of the oscillation shape using sinusoidal excitation on shear thinning as a function of different fiber reinforcement percentages is also investigated. A phenomenological view describes the mutually influencing parameters with regard to different material compositions and different excitation frequencies over the time course of the rheometric measurement. Interacting relationships are analyzed and discussed and the potential of the actuator system to influence the plastic melt is worked out. Based on this, a technological approach follows which describes the transfer of an oscillating mold surface to plastics processing methods, which, especially in the case of energy-intensive injection molding technology, leads to the expectation of possible resource efficiency in energy and material.
The aim of this study was to investigate the antimicrobial efficacy of different disinfection protocols in a novel Enterococcus faecalis biofilm model based on a visualization method and to evaluate the potential alteration of dentinal surface. A total of 120 extracted human premolars were allocated to 6 groups with different irrigation protocols. The assessment of the effectiveness of each protocol and the alteration of dentinal surface were visualized by using SEM and fluorescence microscopy (DAPI). A dense E. faecalis biofilm with a penetration depth of 289 μm (medial part of the root canal) and 93 μm (apical part) validated that the biofilm model had been successfully implemented. A significant difference between the 3% NaOCl groups and all the other groups in both observed parts of the root canal (p < 0.05) was detected. However, the SEM analysis revealed that the dentinal surface in the 3% NaOCl groups was severely altered. The established biofilm model and the visualization method based on DAPI are appropriate for bacterial quantification and evaluation of the depth effect of different disinfection protocols in the root canal system. The combination of 3% NaOCl with 20% EDTA or MTAD with PUI allows the decontamination of deeper dentine zones within the root canal but simultaneously alters the dentinal surface.
Abstract: This article reconstructs the path of the German economist Friedrich A. Lutz (1901–75) to American economics. The correspondence with his former teacher Walter Eucken, the founder of the Freiburg school, constitutes a crucial yet unexplored source for the article. Through Lutz's case, this article demonstrates the growing gulf between German and Anglo-Saxon economics during the late 1930s. In his native Germany, Lutz was trained in methodologically and institutionally focused economics, which differed fundamentally from the mathematical economics dominating Anglo-Saxon academia. He realized that an academic career in the United States would be impossible if he did not adapt to the new methods and if he did not abandon the methods of the German tradition. This gave rise to his internal Methodenstreit. After his emigration in 1938, he constantly experienced doubts and tensions because he was convinced that without considering institutions, mathematical economics could never explain the occurrence and essence of macroeconomic phenomena. Despite his stellar career at Princeton, it was only after his move to Zurich in 1953, where he taught history and theory of socioeconomics for the rest of his life, that Lutz could reconcile this internal Methodenstreit.
Emotionale Kompetenzen und psychische Gesundheit: Eine Querschnittstudie in Gesundheitsberufen
(2021)
Hintergrund
Im Jahr 2020 waren 5,7 Mio. Menschen in Gesundheits- und Pflegeberufen tätig. Der Kontakt mit anderen Menschen ist in diesen Berufen Teil des Arbeitsauftrags und der Mensch ist der Arbeitsgegenstand.
Ziel der Arbeit
Das Ziel der Arbeit ist die Untersuchung der Auswirkung von psychischer Belastung (Arbeitsintensität, Spielräume), emotionaler Erschöpfung und emotionalen Kompetenzen (Regulation) auf das psychische Wohlbefinden bei Beschäftigten in Gesundheitsberufen.
Material und Methoden
Die Erhebung der Querschnittstudie von 624 Beschäftigten aus der Altenpflege und dem Rettungsdienst (72,5 % weiblich) erfolgte im Rahmen zweier Projekte zur betrieblichen Gesundheitsförderung. Zum Einsatz kamen standardisierte validierte Verfahren, welche mittels Korrelationsanalysen sowie einer hierarchischen Regressionsanalyse zur Vorhersage des psychischen Wohlbefindens ausgewertet wurden.
Ergebnisse
Hohe Arbeitsintensität, hohe Spielräume, hohe emotionale Erschöpfung und eine hohe emotionale Kompetenz (Regulation) tragen zur Aufklärung des psychischen Wohlbefindens bei (R2 = 33 %).
Schlussfolgerung
Anhand der Ergebnisse wird deutlich, dass neben dem Erleben von Arbeit und Gesundheit auch emotionale Kompetenzen einen Einfluss auf die psychische Gesundheit bei Beschäftigten in Gesundheitsberufen haben. Damit leistet die Studie einen wichtigen Beitrag für die Entwicklung von Maßnahmen des betrieblichen Gesundheitsmanagements in diesen Berufsgruppen.
Electrical and thermal measurements were conducted during the plasma electrolytic polishing (PEP) of cemented tungsten carbide (WC-Co) materials to characterize energetic aspects of the process in relation to the temporal development of the gaseous layer near the workpiece. The power transferred to the workpiece is determined using a calorimetric probe and employing the time derivative of the temperature curve. It shows distinct heating phases due to the generation of the gaseous layer. At the beginning of the process, a typical power of 367 ± 17 W is transferred to the workpiece of a surface area of 14 cm2. At longer process times, a stabilized gaseous layer limits the power transferred to the workpiece to 183 ± 3 W. In an attempt to describe the heat transferred to the electrolyte, the electrolyte temperature was measured using a thermocouple situated 15 mm away from the workpiece. The local electrolyte temperature increases from 70 to 81 °C for an immersion depth of 20 mm. Moreover, the spatiotemporal development of the electrolyte temperature was obtained by 2D-hydrodynamic modeling using COMSOL Multiphysics®. The modeling results for the local temporal temperature development are in excellent agreement with the experimental values when the turbulent model is applied up to t = 65 s. Afterward, the laminar model leads to a better agreement. Furthermore, line scan x-ray photoelectron spectroscopy revealed that aliphatic carbon was preferentially removed. Only a slight compositional gradient in the vertical direction after the PEP process was observed.
Hintergrund: Der überwiegende Teil der Patienten in Deutschland verstirbt entgegen ihres Wunsches nicht zu Hause. Eine Entscheidungshilfe für das notfallmedizinische Team kann nachfolgende Klinikeinweisungen von Patienten am Lebensende vermeiden.
Material und Methoden: Die Entscheidungshilfe Notarzt wurde im Rahmen des G-BA-Projektes AVENUE-Pal basierend auf einem Expertenkonsens mittels qualitativer und quantitativer Befragungen entwickelt. Sie stellt einen Teilaspekt des Gesamtprojektes dar.
Ergebnisse: Die EH Notarzt definiert 7 Ziele, die durch die Dimensionen „Information“, „Beratung“, „Unterstützung“, „Schulung“, „Anleitung“, „Übung“, „Kooperation“ und „Dokumentation“ erreicht werden sollen. Die EH Notarzt stellt eine Möglichkeit der Optimierung der notfallmedizinischen Behandlung von Patienten am Lebensende dar.
Diskussion: Die EH Notarzt ist eine Entwicklung zur Verbesserung der präklinischen Versorgung von Patienten am Lebensende und zur Vermeidung von Klinikeinweisungen am Lebensende. Derzeit ist die EH Notarzt ein theoretisches Hilfsmittel, welches in die praktische Anwendung überführt werden und weiterhin an die Notwendigkeiten der täglichen Patientenversorgung angepasst werden muss.
This paper presents numerical analysis of the discrete fundamental solution of the discrete Laplace operator on a rectangular lattice. Additionally, to provide estimates in interior and exterior domains, two different regularisations of the discrete fundamental solution are considered. Estimates for the absolute difference and lp‐estimates are constructed for both regularisations. Thus, this work extends the classical results in the discrete potential theory to the case of a rectangular lattice and serves as a basis for future convergence analysis of the method of discrete potentials on rectangular lattices.
Dynamically loaded structures made of thermoplastic polymers have been extensively exploited in several demanding industries. Due to the viscoelastic and thermal properties of thermoplastic polymers, self-heating is generally inevitable, especially during dynamic deformations at high frequencies. Therefore, the thermoplastic polyether ether ketone (PEEK), with its high temperature resistance and high specific strength, is a particularly ideal candidate for dynamically loaded applications. Using scanning laser Doppler vibrometry and infrared thermography, an experimental study of the vibration characteristics and the vibration-induced heating of flat-sheet PEEK specimens was carried out. The specimens were base-excited by means of a piezoelectric actuator at high frequencies in the range between 1 and 16 kHz. As a result, a maximum temperature rise of approximately 6.4 K was detected for the highest investigated excitation. A high correlation between the spatial distribution of the velocity along the beam’s axial direction and the resulting temperature increase was measured. To summarize, the occurring self-heating of PEEK due to the dissipation of vibrational energy has to be critically considered for dynamically loaded structural applications, especially areas with high displacement amplitudes, such as antinodes, which yield the highest temperature increase.
Experimental tests on the type-approval of motor vehicles with regard to safety belt anchorages, ISOFIX anchorages and ISOFIX top anchorages have been carried out in accordance with Regulation No. 14 UNECE. From the design stage, the safety belt anchorages must comply with the requirements for the installation of a safety belt and reduce slipping and damage to the belt while wearing it. These can be components of the seat structure or of the body's resistance structure, which have the role of fastening the seat belts. The position of the anchor points is determined by the R point. The R point is defined as the seat reference point on the seat. This point is set by the vehicle manufacturer for each seat in the vehicle. In this paper, two models of chairs were tested. Both seat models are equipped with seat belts anchored at three anchor points. Seat belt anchorages were tested simultaneously using parallel force devices. These traction devices are placed on the seat cushion and are pressed into the seat back. The pulling device has a vertical pulling arm, which has the role of anchoring the steel wire cables. Two test forces are applied simultaneously to the anchor points during the test.
This study aimed to investigate the component structural behaviour and response under overturned truck crash that subsequently collides with road-side pole or tree. The safety of the truck occupants in an accident is very important and should be considered in the process of cabin design. Specific focus will be on the structural integrity of the truck cabin in response to a collision with a cylindrical pendulum. In the past, dynamic analysis was done by real world testing. Nowadays crash simulation is proven to be much more efficient by being a virtual representation of destructive crash impact and providing opportunities to reduce the number of physical prototypes consumed for design verification, thus reducing development time. According to cab strength tests (ECE R29), the cabin body of the truck shall be attached to the chassis in such a way that in the event of impact it ensures a sufficient survival space and eliminates the risk of injury. This paper investigates the FE (finite element) simulation of a frontal impact on the cabin structure to validate the cabin according to the ECE regulation 29 tests. The study also includes the assessment of the energy absorption capabilities of the cabin during the pendulum impact. The pendulum impact was carried out using Ansys LS-Dyna explicit solver to evaluate the cabin strength under the loads.
Abstract: Die Automobilproduktion steht aktuell vor der Herausforderung, einen sich weiter diversifizierenden Antriebsmix effizient zu produzieren. Der vorliegende Beitrag erläutert die grundsätzlichen Einflüsse alternativer Antriebsarten auf die Fahrzeugproduktion, welche mithilfe umfangreicher Experteninterviews ermittelt wurden. Diese Erkenntnisse können genutzt werden, um langfristig die richtigen Produktionsstrategien für die Gestaltung effizienter Produktionsnetzwerke abzuleiten.
Stefan Kolev zeichnet in seinem Beitrag die Geschichte und Bedeutung des schillernden Begriffs »Neoliberalismus« nach, welcher vielfach als Grund allen Übels gegen liberales Denken und Politik in Stellung gebracht wird. Kolev plädiert dafür, dass der Liberalismus sich immer wieder erneuern muss, also stetig neue Neoliberalismen benötigt.
LEGO robotics sets are a well established tool for teaching programming in undergraduate courses. Starting with the now outdated EV3 set LEGO provided a Python programming interface and (inofficial) Linux support. The current LEGO Spike Prime set still provides Python programming, but no direct support for Linux.
In this report we collect and extend information on controlling Spike Prime robots from Linux hosts. We cover access to a robot's Python interpreter and code transfer as well as bidirectional robot-to-host communication via USB and Bluetooth. Results may be extended to robot-to-robot communication via Bluetooth.
Hybrid manufacturing of titanium Ti-6Al-4V combining laser metal deposition and cryogenic milling
(2020)
Hybrid manufacturing, which, e.g., combines additive manufacturing with conventional machining processes, can be a way of overcoming limitations currently encountered in additive manufacturing. Cryogenic milling might be a viable option for hard-to-cut materials, as it leaves a contamination-free surface and can increase surface quality and tool life compared to conventional cooling concepts. In this study, the influence of cryogenic milling with carbon dioxide on titanium Ti-6Al-4V specimens manufactured with laser metal deposition (LMD) was investigated regarding tool wear and surface integrity in comparison to dry machining and machining with cooling lubricants. Moreover, additional layers of material were deposited on top of conventionally and cryogenically machined surfaces by means of LMD. The interface zone was then examined for defects. The milling process was closely monitored by means of thermal and high-speed imaging. Optical and tactile surface analysis provided evidence that lower roughness values and improved surface qualities could be obtained with cryogenic machining in comparison to dry machining. Moreover, significantly less tool wear was observed when a cryogenic cooling medium was applied. Although the utilization of conventional cooling lubricants resulted in satisfying surface qualities, substantial residual contamination on the milled surface was detected by means of fluorescence analysis. These contaminants are suspected to cause defects when the next layer of material is deposited. This is supported by the fact that pores were found in the weld bead applied on top of the milled specimens by means of LMD. Conversely, cryogenic machining resulted in very clean surfaces due to the residue-free evaporation of the coolant. Hence, a good metallurgical bonding between the weld bead and the milled substrate could be achieved. The results indicate the great potential of cryogenic milling in hybrid manufacturing, especially in terms of intermediate machining, as it provides residue-free surfaces for subsequent material deposition without an additional cleaning step and can significantly prolongate tool life.
The atomizing gas dynamics and the applied process energy have a significant influence on the produced particles. The melting process of the two wires can be influenced by current modulation. As for arc welding processes, more and more electronic and software-controlled machines are being used for arc spraying and will have replaced conventional power sources in the future. Due to the highly dynamic, fast regulating computing technology in the latest energy source, technology arcs can be operated with different current forms and types. The modern machines allow process-stable, reproducible variation of the particles and heat input into the substrate. Constant and pulsed current can be used as current forms. Usable current types are direct current (DC) and alternating current (AC). The electrical parameters must be analyzed to evaluate the process behavior. The consumable used is a wire-shaped iron-based alloy with a diameter of 1.6 mm. Relevant process parameters such as basic current Iground, pulse current Ipulse, pulse duration tpulse, impulse frequency fpulse, and alternating current frequency, fAC, are varied and recorded using appropriate measurement technology. The aim is to change the process performance and thereby the particle formation in a broad band. High-speed images are used to observe the arc and the deposition process. In addition, particle sizes are determined.
The intention of the paper is to consider the role of technologies used to overcome the COVID-19’s challenges in higher education. On investigating, it has been found that the digital strategies utilizing innovation technologies help students to adapt to pandemic consequences. This study enlightens the various technologies that assist systems of healthcare and education in diverse aspects to outlive against COVID-19. Furthermore, the technological shift of world economy that happened during the pandemic and its influence in the society is discussed. Besides the considered innovation technologies, this paper also deals with changes that have taken place in education system of Kazakhstan in pandemic circumstances. Alongside our suggested solution for further educational process issues is also presented.
A detailed review of the literature is done on COVID-19, digital technologies in education, blended learning using appropriate keywords on SCOPUS, Springer, Science Direct, and Google Scholar. To get insights some relevant sites and blogs are also taken into account. We have identified technologies used in Kazakhstan that play an important role now.
There have been chosen exploratory and conclusive research design. Fifty-nine students provided qualitative responses; ninety-eight students and graduates participated in quantitative survey. The results of study has shown students’ increased awareness concerning blended learning.
The scientific novelty lies in the description of the experience gained by higher schools during the quarantine. We believe that in the future, blended learning should be used largely. The innovations in the learning process cover two areas. The first is related to software used. It is like creation of a virtual university that facilitates communication between students and teachers. The second area correlates with content, without which any innovation will fail.
Integration und Migration werden in Deutschland nie an Bedeutung verlieren. Ob als Gastarbeiter in den 1950er Jahren, Flüchtling in den 1970er Jahren oder Vertragsarbeiter in den 80ern, Deutschland hat über Jahre hinweg zahllose Migranten aufgenommen. Doch keine Migrantengruppe wird derzeit in den Medien positiver erwähnt als die der Vietnamesen.
Ziel dieser Arbeit ist es aufzuzeigen, wie sich die Integration der Vietnamesen aus deutscher und vietnamesischer Sicht unterscheiden bzw. ähneln. Dazu wurden folgende Forschungsfragen gestellt: Sehen die deutschen Bürger die Vietnamesen tatsächlich als voll integriert? Und wie schätzen die Vietnamesen selbst ihre Integration ein? Um diese Fragen zu beantworten, sind vier qualitative Interviews mit zwei deutschen Staatsbürgern deutscher Herkunft, einer Vietnamesin, die in die damalige DDR als Vertragsarbeiterin kam, und einer Vietnamesin zweiter Generation, die in Deutschland geboren und aufgewachsen ist, durchgeführt worden. Die Interviews wurden auf Meinungen im Hinblick auf die vietnamesische Integration untersucht. Im Großen und Ganzen kann gesagt werden, dass trotz einiger Divergenzen hinsichtlich der geäußerten Sichtweisen, die Interviewten fast einstimmig der Meinung sind, Vietnamesen seien gut in die deutsche Gesellschaft eingegliedert - auch wenn das, was sie unter Integration verstehen, teilweise stark von den wissenschaftlichen Definitionen abweicht.