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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.
Die Publikation untersucht die Einordnung der Führung in den Managementkontext und stellt das Konzept "Digital Leadership" als neue Managementkompetenz vor. Sie identifiziert Grundanforderungen an die Führungsrolle und betont die Herausforderungen für Führungskräfte in der digitalen Arbeitswelt. Dabei wird die Vielfalt der Grundanforderungen an die Führung aufgezeigt, indem die Wahl des Führungsstils, der Faktor „Motivation“ und das KLARA-Prinzip hervorgehoben werden. Der digitale Wandel erfordert die Anpassung der führenden Personen an die Herausforderungen der digitalen Transformation und die Fähigkeit, sich in verschiedene Führungsrollen hineinzuversetzen.
Die Publikation untersucht Home-Office im Kontext des "Digital Leadership", erörtert technische, organisatorische und führungspolitische Anforderungen und beleuchtet Chancen sowie Risiken dieser Arbeitsform. Es wird ein Überblick zur aktuellen Home-Office Situation in Deutschland gegeben. Zudem werden die Unternehmen "Compart AG" und "Microsoft" als Best-Practice-Beispiele hervorgehoben. Ziel ist es, die Voraussetzungen und erfolgreiche Umsetzungsmöglichkeiten des Home-Office zu analysieren.
Die Publikation analysiert die Arbeitssituation im Home-Office in Deutschland und identifiziert Anforderungen an Führungskräfte und Mitarbeiter. Führungskräfte sollten den partizipativen Führungsstil anwenden, die Fähigkeit zu motivieren besitzen sowie moderne Technologien nutzen. Mitarbeiter werden zu Eigenmotivation, Feedback und eigenverantwortlichem Arbeiten angehalten. Positive Aspekte der Telearbeit sind Flexibilität und Zeitersparnis, während fehlende Tätigkeitseignung und mangelnde Interaktion als Nachteile gelten. Die Handlungsempfehlungen, welche in Form von Checklisten gestaltet sind, beschreiben die Anforderungen an Führungskräfte und Mitarbeiter an die Telearbeit. Das Fazit in Kapitel drei rundet die Ergebnisse ab.
Das Hauptziel der Arbeit ist die Analyse der o.g. Anforderungen und die Ableitung von Handlungsempfehlungen für das Home-Office.
The book 'Reinforcement 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.
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.
Multiplikatorenkonzepte zu Stress- und Emotionsregulation im Rettungsdienst – ein Scoping-Review
(2024)
Hintergrund: Beschäftigte im Rettungsdienst sind einem erhöhten Risiko ausgesetzt, psychische Beeinträchtigungen zu entwickeln, da sie in ihrem Berufsalltag hohen körperlichen und emotionalen Stressoren ausgesetzt werden. Der Umgang mit diesen Stressoren stellt eine wichtige Ressource dar, um im Sinne der Salutogenese eine Bewältigung vorzunehmen. Damit die Förderung der Stress- und Emotionsregulation nicht nur auf einer Verhaltensebene wirksam wird, bieten sich Multiplikatorenkonzepte mit einer verhältnisbezogenen Verzahnung in die Arbeitssysteme an.
Ziel der Arbeit: Die Überprüfung der verfügbaren Evidenz von Multiplikatorenkonzepten zur Stress- und Emotionsregulation im Rettungsdienst ist das Ziel des Scoping-Reviews.
Material und Methoden: Die Übersicht orientiert sich inhaltlich am Modell der Salutogenese und methodisch am Konzept des Joanna Briggs Institute zur Durchführung von Scoping-Reviews. Die Recherche basierte auf den Suchoberflächen PubMed sowie PubPsych (alle Evidenzquellen) und erstreckte sich auf deutsch- und englischsprachige Literatur im Zeitraum von 1997 bis 2023. Alle Schritte der Datensichtung und -extraktion wurden von zwei Reviewern unabhängig voneinander durchgeführt.
Ergebnisse: Für die Überprüfung der verfügbaren Evidenz wurden insgesamt 22.345 Datensätze identifiziert und gesichtet. Abschließend konnten vier Volltexte eingeschlossen werden. Die Interventionen richten sich neben Mitarbeitenden des Rettungsdiensts auch an andere Berufsgruppen. Alle Trainings sind modular aufgebaut. Die psychosozialen Widerstandsressourcen sind vielfältig. In drei von vier Studien können kleine Ergebnisse belegt werden; eine Intervention erhöht die Selbstwirksamkeit der Teilnehmenden.
Diskussion: Es gibt weltweit keine spezifischen Konzepte, die sich explizit an Mitarbeitende des Rettungsdiensts richten. Gezielte Interventionen sind aufgrund der hohen Belastungen der Berufsgruppe erforderlich.
OpenStreetMap (OSM) is a large open database for geographic data created and maintained by volunteers. OSM's main data use is rendering an extremely detailed map of the world. Data quality is an important issue for applications like routing of pedestrians to public transport facilities. In this report we describe different schemes for mapping bus stops in OSM and we provide statistics on usage of those schemes, the good ones and the not so good ones.
Tourismus und Mobilität sind untrennbar miteinander verbunden. In erster Linie mag man dabei an die An- und Abreise zur Urlaubsdestination denken. Aber auch für Aktivitäten vor Ort sind Verkehrsmittel bzw. Verkehrsinfrastrukturen von entscheidender Bedeutung. Sie können sogar, z.B. bei Kreuzfahrten oder mehrtägigen Fahrradtouren, einen wesentlichen Bestandteil der Reise ausmachen oder aber, wie etwa imposante Brückenbauwerke oder Dampfbahnen, selbst als Attraktion gelten.
Zahlreiche Beispiele sowie 40 Fallstudien, die auf eigenen Erfahrungen beruhen, illustrieren die aufgegriffenen Themen und sollen beim Leser „Entdeckergeist“ wecken, um interessanten Ideen und Entwicklungen in der Realität auch selbst nachzugehen.
Sustainable Integration of Digitalisation in Nursing Education - An International Scoping Review
(2024)
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.
Model predictive control (MPC) is a promising approach to the lateral and longitudinal control of autonomous vehicles. However, the parameterization of the MPC with respect to high-level requirements such as passenger comfort, as well as lateral and longitudinal tracking, is challenging. Numerous tuning parameters and conflicting requirements need to be considered. In this paper, we formulate the MPC tuning task as a multi-objective optimization problem. Its solution is demanding for two reasons: First, MPC-parameterizations are evaluated in a computationally expensive simulation environment. As a result, the optimization algorithm needs to be as sample-efficient as possible. Second, for some poor parameterizations, the simulation cannot be completed; therefore, useful objective function values are not available (for instance, learning with crash constraints). In this work, we compare the sample efficiency of multi-objective particle swarm optimization (MOPSO), a genetic algorithm (NSGA-II), and multiple versions of Bayesian optimization (BO). We extend BO by introducing an adaptive batch size to limit the computational overhead. In addition, we devise a method to deal with crash constraints. The results show that BO works best for a small budget, NSGA-II is best for medium budgets, and none of the evaluated optimizers are superior to random search for large budgets. Both proposed BO extensions are, therefore, shown to be beneficial.
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.
The labor market is confronted with social, environmental, and economic developments that affect working conditions and individual labor relations. Lately, the Covid-19 pandemic has demonstrated and reinforced the importance of inclusive growth and sustainable work relationships. In this chapter, the smart job factory, a metamodel that supports the creation of new forms of work by redefining roles in labor, is introduced. The smart job factory is based on social entrepreneurship principles to drive innovative, sustainable, and long-term solutions to social challenges. For practical application, the model can be translated into a software solution that supports employers in the assessment of current working conditions and job roles within their companies and helps to redefine work relationships and to create new jobs. Thus, the smart job factory supports the labor market transition by systematically and proactively shaping new forms of work based on the triple bottom line of sustainable development.
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.
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.
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.
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.
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
This paper deals with systematic approaches for the analysis of stability properties and controller design for nonlinear dynamical systems. Numerical methods based on sum-of-squares decomposition or algebraic methods based on quantifier elimination are used. Starting from Lyapunov’s direct method, these methods can be used to derive conditions for the automatic verification of Lyapunov functions as well as for the structural determination of control laws. This contribution describes methods for the automatic verification of (control) Lyapunov functions as well as for the constructive determination of control laws.
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.
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.
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.
This article aims to identify the status quo of sustainability covenants firstly, secondly analyze their possibilities in enhancing sustainability performance and thirdly present further research directions. Covenants are additional contractual agreements mainly used in financial contracts, e.g. loans. They often focus on financial performance indicators, e.g., equity and net debt ratio, which the borrower must fulfil. However, the purpose of this article is to present a new approach to non-financial covenants, so-called sustainability covenants. Therefore, also nowadays ecological and social challenges are addressed. Banks have a huge impact on sustainable development by introducing more non-financial indicators in evaluating the creditability of borrowers. As a key hypothesis, this article argues that the approach of integrating ecological and social objectives through non-financial covenants is underrepresented in economic and business practice. Therefore, this article wants to examine how those objectives can be integrated into the financial concept of covenants and rely on research towards an integrative sustainability approach. In addition, a systematic literature review was conducted from October 2022 to July 2023 to analyze the status quo and derive future research directions. The review was based on two databases – Google Scholar and Scopus. As one key result, it was revealed that there is scarce existing literature on sustainability covenants, which refers to them as a policy measure. Only a few publications analyze their usage in financial contracts. However, this study implies the necessity for further research on sustainability covenants, emphasizing that they are powerful indicators to enhance the sustainability performance of the borrower.
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.
The research was carried out for the selection of optimal options for the heat supply of multi-apartment buildings, taking as an example several new buildings in Yerevan. The purpose of the study is to confirm the choice of the best method of providing heat in apartment complexes. It was used to calculate and analyze the energy-economic and operational-technical indicators of individual heating boilers, small centralized systems, and hybrid systems to solve this problem. The calculations considered both natural gas tariffs and fluctuations in the value of the Armenian dram against the US dollar. The value of 1 kWh of thermal energy or specific heat capacity has been determined as an important criterion for choosing the most efficient method of heat supply, considering the careful analysis of almost all variable factors.
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.
The demand for thorough disinfection within ambulances is essential, given the in-vehicle medical procedures and the potential high risk of infections due to patients' open wounds. One solution that can address this hygiene challenge involves the application of reactive products generated from atmospheric (air) oxygen and water vapor, activated through the use of cold plasma. Cold plasma's charged particles perforate the cell membranes of microorganisms. This process does not work in human cells, as proteins in the form of enzymes within the body break down the cold plasma and protect the cells. The study was done on an ambulance that was contaminated in eight places. Samples were taken from each site, and two surfaces measuring approximately 8 × 8 cm were carefully sealed and marked. These surfaces were deliberately contaminated by applying an Enterococcus faecium suspension of 8.5 × 107 CFU/mL using a sterile cotton swab. It was followed by the disinfection procedure, that was initiated with the PLASMOCAR device. It was positioned on the front workspace and operated for a duration of 30 min, utilizing the vehicle's onboard voltage. Throughout the operation, all doors and windows were closed and the vehicle's air conditioning system remained active. After the completion of the disinfection process, samples were collected from the surfaces for bacterial counts. A reduction of 3.73 log levels in initial bacteria was accomplished within the rescue vehicle for Enterococcus faecium, equivalent to a 10–fourfold reduction in bacteria, eliminating up to 99.99% of the initial microorganisms. This success makes the process well-suited and convenient as an ongoing "background" procedure to enhance the established disinfection procedures. The established disinfection procedures outlined in the hygiene plan must be promptly implemented whenever mechanical surface cleaning is required. The use of PLASMOCAR offers an extra layer of protection and security, significantly decreasing the risk of microorganism transmission through cross-contamination and aerosols. This is a significant benefit for the well-being of both staff and patients.
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.
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.
Die für die Planung des Materialflusses relevanten Fertigungsprozesse lassen sich sehr genau planen, beispielsweise über die Leistung der Maschine (Durchsatz je Zeiteinheit). Bei der Planung eines Projektes spielen logistische Prozesse, die zu den Kernprozessen eines Unternehmens gehören, eine wichtige Rolle. Jedoch werden sie meist nur grob terminiert und mit großen Puffern kalkuliert. Dies kann zu einer Verlängerung der Projektdauer führen. Für eine genauere Terminierung eines Projektes ist es daher entscheidend, die Dauer der logistischen Prozesse mindestens in dem Maße wie die Fertigungsprozesse zu ermitteln, um das Risiko einer Projektverzögerung zu minimieren.In diesem Beitrag wird deshalb eine Methode zur datenbasierten Schätzung von Prozessdauern mit dem Ziel der Wiederverwendung von Projektwissen vorgestellt, die es dem Projektmanagement ermöglichen soll, Dauern von logistischen Prozessen präziser zu schätzen als das aktuell basierend auf Erfahrungswissen erfolgt. Besonderes Augenmerk liegt dabei auf der Herleitung der Entwurfsaktivitäten. Durch die Anwendung der Methode soll das Projektmanagement von einer genaueren, datenbasierten Schätzung von (Logistik‑)Prozessdauern profitieren und so entstandenes Wissen über einen Ontologieansatz wiederverwenden können.
Standardfälle Arbeitsrecht
(2023)
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.
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.
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.
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.
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.
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.
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.
Routing games over time are widely studied due to various applications, e.g., transportation, road and air traffic control, logistic in production systems, communication networks like the internet, and financial flows. In this article, we present a new competitive packet routing game with edge priorities motivated by traffic and transportation. In this model a set of selfishly acting players travels through the network over time. If the number of players who want to enter an edge at the same time exceeds the inflow capacity of this edge, then edge priorities with respect to the preceding edge are used to resolve these conflicts, which is similar to right-of-way rules in traffic. We analyze the efficiency of pure Nash equilibria, present an efficient algorithm for computing equilibria in symmetric games, and show that it is NP-hard to decide whether a Nash equilibrium exists in an asymmetric game. Furthermore, we address the problem of constructing optimal priorities.
Narrations autour du café sur le site web de Nespresso France: Exclusivité, exotisme et durabilité
(2022)
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.
In this work, a new method for selecting suitable materials is presented. This method has a high potential for a variety of engineering applications, such as the design of sound-absorbing and vibration-loaded structures, where a large number of different requirements have to be met. The method is based on the derivation of functional dependencies of selected material parameters. These dependencies can be used in parameter studies to consider parameter combinations that lie in the range of real existing and targeted material groups. This allows the parameter space to be reduced, the calculation to be accelerated, and suitable materials to be (pre-)selected for the respective application, which contributes to a more target-oriented design. The method is applied to the example of a plate resonator. For this purpose, a semi-analytical model is implemented to calculate the transmission loss as well as the reflected and dissipated sound power of plate silencers, taking into account the influence of flow velocity and fluid temperature on the performance of plate silencers.
Die fortschreitende Vernetzung von Geräten im Internet der Dinge in Kombination mit der Digitalisierung verändert Märkte und Branchen nachhaltig. Im Rahmen des DiWo-Chain Projektes wird an der Entwicklung und lokalen Integration der Blockchain-Technologie in digitale Dienstleistungen der Wohnungswirtschaft geforscht. Durch die verwendete Blockchain-Technologie soll die Gestaltung von effizienten, betriebs-, manipulations- und datenschutzsicheren Dienstleistungen der Wohnungswirtschaft ermöglicht werden. In diesem Beitrag wird eine Lösung beschrieben, welche die Integration und Realisierung vereinfacht. Zur Umsetzung wurde eine Java OSGi-Anwendung in Kombination mit einer Angular-Anwendung für die Interaktion mit der Hyperledger Fabric Blockchain entwickelt. Diese Blockchain-basierte Lösung kann dynamisch für diverse Anwendungsfälle angepasst werden. In diesem Beitrag werden ausgewählte Szenarien der Wohnungswirtschaft beschrieben, die für den Einsatz der entwickelten Lösung geeignet sind.
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.
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.
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.
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.
Der General
(2022)