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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.
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.
The purpose of this study is to examine the relationship between contextual work-related factors in terms of job demands (workload-WL) and job resources (work flexibility-WF), work-life conflict (WLC) and the burnout dimension emotional exhaustion (EE) in a large population-based sample. Building on the job demands resources model (JDRM), we have developed the hypothesis that WL has an indirect effect on EE that is mediated by WLC. We conducted a secondary analysis using data from the Dresden Burnout Study (DBS, N = 4246, mean age (SD) = 42.7 years (10.5); 36.4% male). Results from structural equation modelling revealed that EE is positively associated with WL (β = 0.15, p = 0.001) and negatively associated with WF (β = -0.13, p = 0.001), also after accounting for potential confounding variables (demography, depressive symptoms, and lifetime diagnosis of burnout). Both effects are mediated by WLC (β = 0.18; p = 0.001 and β = 0.08; p = 0.001, respectively) highlighting the important role of WLC in employee health. In summary, WF may help to reduce burnout symptoms in employees, whereas WL may increase them. Study results suggest that both associations depend on WLC levels.
Die Seminararbeit untersucht die Bedeutung der strategischen Personalentwicklung und Kompetenzförderung im spezialisierten Bereich des Sondermaschinenbaus, mit einem Fokus auf die Praxis der Skill-Checks in einem deutschen Unternehmen. Sie beleuchtet die Auswirkungen des demografischen Wandels, der rasanten technologischen Entwicklungen und der Globalisierung auf den Bedarf an Fachkräften mit spezifischen technischen und sprachlichen Kompetenzen. Durch eine detaillierte Analyse der bestehenden Ausbildungs- und Weiterbildungsprozesse werden Schwachstellen aufgezeigt. Die Arbeit schlägt Lösungsansätze vor, wie durch strukturierte Weiterbildungsprogramme und verbesserte Auswahlverfahren diesen Herausforderungen effektiv begegnet werden kann, um die Wettbewerbsfähigkeit zu stärken.
This paper embeds the early political economy of Friedrich August von Hayek in the intellectual milieu of German ordoliberalism. The urgency during the 1930s and 1940s to stabilize the disintegrating societal orders is identified as a crucial driver behind the parallelisms between Hayek and the ordoliberals. Their shared theoretical position is that in such moments, liberty can thrive sustainably only after a framework of general and stable rules has been established. Hayek’s proximity to ordoliberalism was most explicitly discernible in The Road to Serfdom and at the founding meeting of the Mont Pèlerin Society in 1947, culminating in the shared politico-economic vision of the competitive order. The contextual nature of Hayek’s ordoliberalism surfaced in the years after The Constitution of Liberty when his focus shifted, along with the postwar intellectual and institutional stabilization of the West: from how stable orders enable liberty, to how liberty enables the evolution of orders.
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.
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.
En 1985 inició el Ministerio de Educación en Venezuela el Modelo de Atención Integral al Niño Sordo, un cambio de la práctica oralista a un modelo bilingüe en las escuelas de sordos. Eso implicaba eliminar la enseñanza del español hablado como objetivo principal e introducir la Lengua de Señas Venezolana (LSV) a las escuelas. Se desencadenó así un intenso período de cambios que marcó indeleblemente a la comunidad sorda. Aquí se aborda el Modelo desde la perspectiva de la planeación lingüística, describiendo sus objetivos y sus efectos sobre la adquisición, la estructura (el corpus) y el estatus de la LSV: La LSV y el español señado fueron reubicados en la diglosia existente hasta entonces; surgió una variante académica de la LSV y aumentó el número de usuarios de la LSV. El estudio se basó en el análisis cualitativo de entrevistas realizadas a cinco testigos de aquel proceso.
Hintergrund/Zielstellung: Aufgrund des gestiegenen Informationsbedürfnisses von Patienten wird für Ärzte ein eigener Webauftritt als Informationsmittler mit dem Ziel der Patientengewinnung und -bindung zunehmend bedeutsam. In der vorliegenden Studie wurde daher die Patientenorientierung der Internetauftritte niedergelassener Fachärzte für Orthopädie und/oder Unfallchirurgie in Sachsen untersucht.
Methode/Stichprobe: Alle Websites der im Arztregister der Kassenärztlichen Vereinigung Sachsen gelisteten Fachärzte für Orthopädie und/oder Unfallchirurgie wurden mithilfe einer standardisierten Checkliste analysiert.
Ergebnisse: Von allen untersuchten Fachärzten (n = 349) besaßen 140 (40,1 %) einen eigenen Internetauftritt. In der Arztpraxis durchgeführte diagnostische Methoden und Therapiemaßnahmen wurden auf je ca. 90,0 % der Websites genannt und auf ca. der Hälfte hiervon erklärt. Der Kontrast konnte auf 10 Websites angepasst werden. Eine Meinungsäußerung wurde den Patienten auf 28 Websites ermöglicht. Rechtlich verpflichtende Impressuminhalte wurden auf 45,0 % der Internetauftritte nicht hinreichend beachtet.
Diskussion/Schlussfolgerung: Die Ergebnisse weisen darauf hin, dass die Gestaltung der Internetauftritte sowie deren Informationsgehalt differieren und Verbesserungspotenziale existieren. Ein standardisierter Kriterienkatalog könnte ein einheitliches Qualitätsniveau gewährleisten und von den Ärzten als Handlungsempfehlung genutzt werden.
Analgesic drug use of recreational and competitive badminton players: Starting points for prevention
(2021)
Objectives: Evidence-based clinical guidelines play an important role in healthcare and can be a valuable source for quality indicators (QIs). However, the link between guidelines and QI is often neglected and methodological standards for the development of guideline-based QI are still lacking. The aim of this qualitative study was to get insights into experiences of international authors with developing and implementing guideline-based QI.
Setting: We conducted semistructured interviews via phone or skype (September 2017–February 2018) with guideline authors developing guideline-based QI.
Participants: 15 interview participants from eight organisations in six European and North American countries.
Methods: Organisations were selected using purposive sampling with a maximum variation of healthcare settings. From each organisation a clinician and a methodologist were asked to participate. An interview guide was developed based on the QI development steps according to the ‘Reporting standards for guideline-based performance measures’ by the Guidelines International Network. Interviews were analysed using qualitative content analysis with deductive and inductive categories.
Results: Interviewees deemed a programmatic approach, involvement of representative stakeholders with clinical and methodological knowledge and the connection to existing quality improvement strategies important factors for developing QI parallel to or after guideline development. Methodological training of the developing team and a shared understanding of the QI purpose were further seen conducive. Patient participation and direct patient relevance were inconsistently considered important, whereas a strong evidence base was seen essential. To assess measurement characteristics interviewees favoured piloting, but often missed implementation. Lack of measurability is still experienced a serious limitation, especially for qualitative aspects and individualised care.
Conclusion: Our results suggest that developing guideline-based QI can succeed either parallel to or following the guideline process with careful planning and instruction. Strategic partnerships seem key for implementation. Patient participation and relevance, measurement of qualitative aspects and piloting are areas for further development.
Trial registration number: German Clinical Trials Registry (DRKS00013006).
Hintergrund
Die Studienzeit ist eine Phase, in der die jungen Erwachsenen mit spezifischen Anforderungen konfrontiert werden. Studierende der Medizin gelten als besonders psychisch belastet. Untersuchungen, in denen sie diesbezüglich mit Studienfächern der gleichen Branche verglichen werden, sind jedoch rar.
Fragestellung
Ziel der Untersuchung war es, die psychische Gesundheit von Medizinstudierenden sowie von Gesundheits- und Pflegemanagementstudierenden zu untersuchen und zu vergleichen.
Material und Methoden
Untersucht wurden Studierende der Studiengänge Gesundheits- sowie Pflegemanagement (WHZ) und Medizinstudierende der (TU Dresden). Verschiedene Aspekte psychischer Gesundheit wurden mithilfe eines Online-Fragebogens erhoben. Dieser beinhaltete die Instrumente zur Erfassung der Prüfungsängstlichkeit (TAI-G-Kurzskala) und psychischen Belastung (BSI-18), sowie ein Item zur Ermittlung der subjektiv wahrgenommenen Studienbelastung. 258 Studierende nahmen an der Befragung teil.
Ergebnisse
Es konnten keine signifikanten Unterschiede hinsichtlich des Gesamtscores der Prüfungsängstlichkeit und der psychischen Belastung zwischen den Studierenden beider Studienfächer festgestellt werden. Dahingegen gaben Medizinstudierende an, dass sie im Vergleich zu Studierenden der anderen beiden Studienfächer eine signifikant höhere Studienbelastung wahrnehmen.
Schlussfolgerung
Die ermittelten Gesamtscores lagen teilweise über den Werten in vergleichbaren Studien. Die Studierenden sollten bereits präventiv unterstützt werden, um eigene Bewältigungsstrategien zu entwickeln. Nicht nur die Bereitstellung von Hilfen ist notwendig, sondern vielmehr das aktive Eingreifen mithilfe von gesundheitsfördernden Maßnahmen durch die Institution Hochschule, in die die Studierenden frühzeitig integriert werden sollten.
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.
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.
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 removal of bacterial infections within the root canal system is still a challenge. Therefore, the cleansing effect of established and new irrigation-protocols (IP) containing silver diamine fluoride (SDF) 3.8% on the whole root canal system was analyzed using quantitative PCR (qPCR) and 4′,6-diamidino-phenylindole-(DAPI)-staining. Extracted human premolars were instrumented up to F2 (ProTaper Gold) under NaCl 0.9% irrigation and incubated with Enterococcus faecalis for 42 days. Subsequently, different ultrasonically agitated IP were applied to the roots: control (no irrigation), 1. NaOCl 3%, EDTA 20%, CHX 2%, 2. NaOCl 3%, EDTA 20%, 3. NaOCl 3%, EDTA 20%, SDF 3.8%, 4. SDF 3.8%, and 5. NaCl 0.9%. One half of the root was investigated fluorescent-microscopically with DAPI. The other half was grinded in a cryogenic mill and the bacterial DNA was quantified with qPCR. The qPCR results showed a statistically significant reduction of bacteria after the application of IP 1, 2, and 3 compared to the control group. While IP 4 lead to a bacterial reduction which was not significant, IP 5 showed no reduction. These data corresponded with DAPI staining. With qPCR a new molecular-biological method for the investigation of the complete root canal system was implemented. The novel IP 3 had an equally good cleansing effect as the already established IP.
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.
Recent surveys and political research have shown that the acceptance of the political programmes of populist parties, such as the “Alternative für Deutschland (AfD)”, is relatively high amongst the population of the three eastern German federal states, especially in Saxony, where the AfD won nine of the 13 rural districts during the local elections in May 2019. Thus, it seems relevant to take a closer look at the persuasive discourse of a so-called populist party. In its public discourse, the AfD responds to the fears and concerns of those people who tend to use social media platforms to gain information when making political decisions. The aim of the article is to show which verbal and visual resources characterize the persuasive discourse of the AFD Saxony on their Facebook account. For this purpose, we propose a qualitative, multimodal analysis of selected entries which the party uploaded on its Facebook account between November 2018 and March 2019.
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.
Traffic calming is introduced to minimise the negative results of motor vehicle use, for example, low safety level or quality of life, high noise and pollution. It can be implemented through the introduction of road infrastructure reducing the velocity and the traffic volume. In this paper, we studied how traffic-calming influences the traffic assignment. For the research, a traffic-calming measure of speed cushions on the Stachiewicza street in Krakow was taken. A method of extracting trajectories from aerial footage was shown, and it was used to build a model. For a given example, through driving characteristics research and microscopic modelling, volume–delay BPR functions were estimated—for a street with and without traffic calming. Later, a toy network of two roads of the same length, connecting the same origin and destination, was simulated using an equilibrium traffic assignment method. Simulations were conducted both with the use of PTV Vissim and Visum software and through individual calculations. According to the results of this paper, there was a difference in traffic volume according to the equilibrium traffic assignment in the aforementioned toy network as a function of total network traffic volume.
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.
Lewis–Mogridge Points: A Nonarbitrary Method to Include Induced Traffic in Cost-Benefit Analyses
(2020)
We propose a new method to estimate benefits of road network improvements, which allows to include the induced demand without arbitrary assumptions. Instead of estimating induced demand (which is nontrivial and hardly possible in practice), we search for demand induction where initial benefits are mitigated to zero. Such approach allows to formulate a dual measure of benefit, covering both the potential benefits and the likelihood of consuming them by the induced traffic. We first estimate benefits of road network improvement assuming that traffic demand is fixed. Consequently, we find demand model configurations at which the benefits of the new investment become null, i.e., all the initial benefits are consumed by the traffic demand growth. We call such states of induced demand the Lewis–Mogridge points of the analysed improvement. We select the most probable of such points and use it to calculate the proposed novel indicator μ, for which the initial benefits (obtained under a fixed-demand assumption) are multiplied with a demand increase rate needed to consume them. We believe that such measure allows to include the critical phenomena of induced traffic and, at the same time, to overcome problems associated with reliable estimation of induced demand. As we illustrate with the case of two alternative road improvement schemes in Kraków, Poland, the proposed method allows to estimate maximal threshold of induced traffic and to select scenario more resilient to induced traffic.
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.
Sodium iron hexacyanoferrate (NaFeHCF) films were electrodeposited on Au/Cr/Si for the study of growth behavior and physical properties. The NaFeHCF films were studied by different analytical methods to prove the chemical composition, morphology and crystal structure. The grains of the film grow with a cubic structure with an average lattice parameter of 10.10 Å and the preferential growth direction along the [111] direction of the cubic cell. The films show a repeatable bipolar resistive switching behavior accompanied by high current changes (up to a factor of ~105). The different resistive states in the materials are dominated by ohmic conduction.
The electrical conduction mechanism of resistive switching Prussian white (PW) thin films obtained by the electrodeposition method was examined by AC impedance spectroscopy and DC current–voltage measurements. Using an electrode tip to contact PW grown over Au, robust unipolar resistive switching was observed with a current change of up to three orders of magnitude, high repeatability, and reproducibility. Moreover, electrical impedance spectroscopy showed that the resistive switching comes from small conductive filaments formed by potassium ions before the establishment of larger conductive channels. Both voltammetry and EIS measurements suggest that the electrical properties and conductive filament formation are influenced by defects and ions present in the grain boundaries. Thus, PW is a potential material for the next generation of ReRAM devices.
Prussian blue (PB) layers were electrodeposited for the fabrication of Au/PB/Ag stacks to study the resistive switching effect. The PB layers were characterized by different techniques to prove the homogeneity, composition, and structure. Electrical measurements confirmed the bipolar switching behavior with at least 3 orders of magnitude in current and the effect persisting for the 200 cycles tested. The low resistance state follows the ohmic conduction with an activation energy of 0.2 eV.
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.
The book 'Reinforcment Learning: An Introduction' by Sutton and Barto is the standard text book for introductory courses to reinforcement learning. Next to concrete algorithms and extensive examples the book contains several fundamental results related to Markov decision processes (MDPs) and Bellman equations in Chapters 3 and 4. Unfortunately some proofs are missing, some theorems lack precise formulation, and for some results the line of arguments is quite garbled.
In this note we provide all missing proofs, give precise formulations of theorems and untangle the line of arguments. Further, we avoid using random variables and their expected values. Since we (like Sutton/Barto) restrict our attention to finite MDPs all expected values can be made explicit avoiding overloaded notation and murky conclusions.
This article bridges the gap between introductory literature like Sutton/Barto and research literature containing exact formulations and proofs of relevant results, but being less accessible to beginners due to higher generality and complexity.
Ziel dieses Beitrags ist die Analyse der folgenden Fragen an das Wahlprogramm Bolsonaros für die brasilianischen Präsidentschaftswahlen 2018: Was sind die Folgen bezüglich des Inhalts und des Ethos des Kandidaten dessen, dass sein Wahlprogramm in Form einer Power Point-Präsentation publiziert wird? Welche Funktion haben die religiösen Textteile für das Ethos des Kandidaten? Welche explizite und implizite Hierarchie der sittlichen Güter und Werte lässt sich aus diesem Programm rekonstruieren? Unter anderem wird die Kohärenz zwischen der Hierarchie der sittlichen Güter, die Privateigentum und nicht das menschliche Leben als höchstes sittliches Gut betrachtet, und der während seiner Regierung verfolgten Nekroplitik aufgewiesen
In diesem Band finden sich das Programm, die Sektionsbeschreibungen und die Abstracts der Vorträge des 15. Deutschen Lusitanistentages, der in der Zeit vom 19.09.-23.09.2023 an der Westsächsischen Hochschule Zwickau stattgefunden hat.
In diesem Artikel sollen einige Aspekte des nachhaltigen Reportings im Sinne der EU-Richtlinien betrachtet werden. Inhaltlich wird die nachhaltige Unternehmensführung unter den Gesichtspunkten der Beschreibung und dem Einfluss der Neuregelung der Transparenzrichtlinien und Offenlegungspflichten auf die Unternehmen fokussiert. Weiterhin wird ein überblicksartiger Einblick in dafür notwendige nachhaltige unternehmerische Prozesse und deren Standards aufgezeigt. Abschließend wird dessen Bezug im Sinne des Reportings sowie eine kritische Bewertung betrachtet.
Die Autoren bringen langjährige Erfahrung in verschiedenen Industriebranchen und der akademischen Ausbildung im Lean- und Project and Process Management mit sich. Im Rahmen der beruflichen Tätigkeit und der akademischen Arbeit hat sich immer wieder die Frage gestellt, wie die Philosophie des Lean Management mit den Aufgaben des Projekt Management Office interagieren können. Viele Ansätze des Lean Management, vor allem organisatorische Methoden zeigen eine breite Anwendungsmöglichkeit und sollten somit auch dem Projekt Management Office (PMO) hilfreich sein. Vor einiger Zeit hat sich schon der Begriff des Lean Office [YDF01] etabliert, der aber sowohl in der Büroorganisation als auch der Dokumentenpflege Ansatz findet. Im Rahmen des PMO soll dieser Lean Office auf die bereitzustellenden Prozesse und deren Integration ins Enterprise Ressource Planning Anwendung finden. Je schlanker und effizienter die Projekt- und Programmprozesse einer Organisation aufgestellt werden, desto leichter können diese abgebildet und in die Enterprise Ressource Planning (ERP)-Datenlandschaft übertragen werden. Somit wird ein solider Grundstein über den gesamten Produktprozess gelegt - von der Entwicklung, über die Herstellung bis hin zur schlussendlichen Verwertung schlank, effizient, automatisiert und digitalisiert abgebildet zu sein.
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.
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.
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.
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.
Im Rahmen dieser Arbeit wird ein statisch-analytisches Modell entwickelt, mit dem eine generalistische Untersuchung von Hufproblemen bei Pferden ermittelt werden kann. Dabei steht nicht die Analyse eines jeden einzelnen Equiden im Vordergrund, sondern vielmehr die typischen Gegebenheiten der territorialen Haltung und die rassebedingten Spezifika.
Zu Beginn müssen die typischen Ursachen und Faktoren ermittelt werden, die einen Einfluss auf den Huf des Pferdes haben können. Dies seien zum Beispiel typische Bodenbegebenheiten, Härte des Bodens, Feuchtigkeit, usw. Diese Ursachen werden mittels einer Ishikawa-Untersuchung ermittelt.
Weiterhin müssen analytische Methoden angeboten werden, mit denen eine entsprechende Untersuchung erfolgen kann. Dies soll aus Gründen der Untersuchbarkeit indirekt über Klebebeschläge erfolgen. Als analytische Messmethoden werden Folgende vorgeschlagen:
- geeignete geometrische/3D-Untersuchungen für „benutzte Duplos“, um hier statistische Trends zu ermitteln
- geeignete Elementanalysen (z.B. XRF), um die chemischen Beanspruchungen aus Richtung Boden und aus Richtung Huf auf das Material zu bewerten
- Beschreibung einer geeigneten Stichprobe anhand von Rasse, Region, Nutzung und Bodenbeschaffenheit in Stall und Umgebung
Das Ziel der Arbeit wird die konkrete Versuchsentwicklung sein, wie man die speziellen Bedürfnisse verschiedener Rassen auf bestimmten Untergrund (sowohl im Stall als auch im territorialen Umfeld) bestimmen kann und was darauffolgend zu beachten wäre.
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.
The Jupyter ecosystem with JupyterHub and JupyterLab as its most prominent members is the de-facto standard for teaching Python programming and also for research in machine learning and data science. Although the Jupyter project is well documented, there are lots of settings and situations requiring deep knowledge of the internal workings of Jupyter, Linux and related software tools. This report describes three problems and possible solutions arising when installing and configuring a Jupyter-based teaching environment. These three problems are the installation and setup of the autograding tool nbgrader, the interplay between JupyterHub and Linux PAM, and providing access to WebDAV resources for users of JupyterHub.
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.
In diesem Artikel wird eine allgemeine Analyse der Stakeholder einer digitalen Produktion bearbeitet. Dabei kommt das Ishikawa-Diagramm für die Analyse zum Einsatz und wird erarbeitet. Über eine Betrachtung des Shopfloors bis hin zu den einzelnen Maschinen wird über den Einsatz von Betrachtungsmethoden des Lean Management die Analyse durchgeführt und ein möglichst umfangreiches Anforderungsbild für die Digitalisierung einer Produktion erarbeitet.