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The quantum anomaly is written alternatively into a form violating conservation laws or as non-gauge invariant currents seen explicitly on the example of chiral anomaly. By reinterpreting the many-body averaging, the connection to Pauli–Villars regularization is established which gives the anomalous term a new interpretation as arising from quantum fluctuations by many-body correlations at short distances. This is exemplified using an effective many-body quantum potential which realizes quantum Slater sums by classical calculations. It is shown that these quantum potentials avoid the quantum anomaly but approach the same anomalous result by many-body correlations. Consequently, quantum anomalies might be a shortcut way of single-particle field theory to account for many-body effects. This conjecture is also supported since the chiral anomaly can be derived by a completely conserving quantum kinetic theory. A measure for the quality of quantum potentials is suggested to describe these quantum fluctuations in the mean energy. The derived quantum potentials might be used to describe quantum simulations in classical terms.
Effect of a community-based lifestyle intervention programme on quality of life among German women
(2021)
Background
Quality of life is an important concept in the field of health, which can be influenced by various lifestyle factors. The objective was to test if a community-based lifestyle programme would beneficially affect the health-related quality of life of German women.
Methods
The controlled intervention study had a total duration of 24 months. Quality of life (EQ-5D-3L), anthropometrics, vital and blood parameters as well as diagnosed diseases and health economic parameters were collected at baseline (t0), after 10 weeks (t1) and after 6 months (t2). For the intervention group (n = 65) a 10-week intensive lifestyle programme followed by monthly alumni meetings were conducted. The intensive phase consisted of 14 consecutive seminars about a healthy lifestyle, which focused on a plant-based diet, physical activity, stress management and community support. The control group (n = 35) received no intervention.
Results
The first descriptive health profile results of the subgroup analysis showed that 59% women of the intervention group at t0 (t1: 37%; t2: 48%) and 60% of the control group at t0 (t1: 54%; t2: 49%) reported problems in at least one of the EQ-5D dimensions (mobility, selfcare, activities, pain, and anxiety). A significant difference in EQ VAS change between women in intervention (7,15 [95% CI 4,32; 9,98]; EQ VAS t0: 75,35 [SD 13,71]) and control group (-2,63 [95% CI -5,40; 0,15]; EQ VAS t0: 78,80 [SD 18,51]) from t0 to t1 was observed (p < 001; adjusted for baseline). No significant differences in mean EQ VAS change from t0 to t2 and in mean EQ-5D index change from t0 to t1 and t0 to t2 between the groups were observed (p > 0,05; adjusted for baseline).
Conclusions
The preliminary results suggest that the lifestyle intervention programme can have a positive short-time effect on some aspects of quality of life, such as the health profile and EQ VAS. However, the long-term results will be shown in the future.
Key messages
- A healthy lifestyle can affect the quality of life in a positive way.
- The community-based lifestyle programme had a short-time influence on the descriptive health profile and EQ VAS of German women, whereby the EQ index didńt change significantly between the groups.
BPMN-based Process-Driven Applications (PDA) require less coding since they are not only based on source code, but also on executable process models. Automated testing of such model-driven applications gains growing relevance, and it becomes a key enabler if we want to found their development on continuous integration (CI) techniques.While process analysts are typically responsible for test case specifications from a business perspective, technically skilled process engineers take the responsibility for implementing the required test code. This is time-consuming and, due to their often different skills and backgrounds, might result in communication problems such as information losses and misunderstandings. This paper presents a new approach which enables an analyst to generate executable tests for PDAs without the need for manual coding. It consists of a sophisticated model analysis, a wizard-based specification of test cases, and a subsequent code generation. The resulting tests can easily be integrated into CI pipelines.The concept is underpinned by a user-friendly tool which has been evaluated in case studies and in real-world implementation projects from different industry sectors. During the evaluation, the prototype proved a more efficient test creation process and a higher test quality.
Innovative business models for data-driven B2B platforms evolve rapidly based on the prospects of digital technology. In addition to the platform provider, service providers on the supply side of the digital platform - the so-called complementors - play an important role in the process of value creation. This paper highlights the complementors’ perspective on the different facets of complementor relationship management (CoRM) and answers the following research questions: From the perspective of a complementor, what are the main fields of CoRM for data-driven B2B platforms? What factors of influence comprise the reason complementors join a platform?
Complementor relationship management for Data-driven B2B platforms: Towards a Holistic approach
(2021)
In the so-called ecosystem economy, new platform-based business models evolve rapidly based on the prospects of digital technology. Especially in the B2B context, data-driven platforms are highly relevant. Thus far, little research has been conducted on the supply side of data-driven platforms and especially on service providers, the so-called complementors. Therefore, this paper offers insights into the various facets of complementor relationship management (CoRM). The paper aims to develop a framework for the management of complementors of data-driven B2B platforms. For empirical evidence, we draw on 14 semi-structured expert interviews with platform managers and complementors. The findings outline two big areas of CoRM and discuss distinct characteristics of partner management and technology management. For partner management the differentiation into open and closed platform needs to be taken into account for complementor relationship management. Moreover, our study reveals the key factors of technology management which lead from platform infrastructure to digital applications like digital twins or predictive maintenance.
In the so-called ecosystem economy, new platform-based business models evolve rap-idly based on the prospects of digital technology. In the B2B context especially, data-driven platforms are highly relevant. Thus far, little research has been conducted on service providers, the so-called complementors of data-driven platforms. Therefore, this paper represents just a starting point for gaining deeper insights into the different facets of complementor management. For empirical evidence, we draw on semi-structured expert interviews with platform managers. The findings outline the distinct characteristics of open and closed platforms which need to be taken into account for complementor management. Moreover, the paper reveals a number of differences in managing suppliers compared to managing complementors. In addition, our study shows that the key factors influencing complementor management include platform openness, partnership intensity, strategic fit, and market structure respectively poten-tial.
In the so-called ecosystem economy, new platform-based business models evolve rapidly based on the prospects of digital technology. Thus far, little research has been conducted on the supply side of digital platforms which also explains the lack of empirical evidence. We develop a framework, categorise complementors, and analyse the main factors of influence for the evaluation and selection of complementors. For our analysis, we consider both industrial IoT platforms as well as financial services platforms. In addition, we use an explorative research design and conduct semi-structured interviews to contribute to this research field. Top-level managers of digi-tal platforms in both industries were interviewed as experts. In addition, the study also considered secondary data to increases the overall reliability and validity in terms of triangulation. As a result, our study reveals both a number of similarities and differences with regard to complementor management for industrial IoT- and financial services platforms.
Experimental results are presented of a test of the theory of local turbulent heat transfer measurements proposed by Mocikat and Herwig in 2007. A miniaturized multi-layer heat transfer sensor was developed and employed in this study. The new heat transfer sensor was designed to work in air and liquids, and this capability enabled the simultaneous investigation of different Prandtl numbers. Two basic configurations, namely the flow past a blunt plate and the flow past an inclined square cylinder, were investigated in test sections of wind and water tunnels. Convective heat transfer coefficients were obtained through conventional testing (i.e., employing thoroughly heated test objects) and using the new miniaturized sensor approach (i.e., utilizing cold test objects without heating). The main prediction of the Mocikat-Herwig theory that a specific thermal adjustment coefficient of the employed actual miniaturized heat transfer sensor should exist in the fully turbulent flow regime was proven for developed two-dimensional flow. The observed effect of the Prandtl number on this coefficient was in good agreement with the prediction of the asymptotic expansion method. The square cylinder results indicated the inherent limits of the local turbulent heat transfer measurement approach, as suggested by Mocikat and Herwig.
Body shaming (BS) is a popular term for a type of negative social interaction, which frequently occurs in social media. However, there is a lack of a clear scientific definition of BS and data on its relation to other concepts in social aggression research. The present study therefore aimed at providing a definition and classification of BS. In an exploratory online-study, 25 participants (60%) provided personal definitions of BS and rated the fit of a suggested definition. In addition, they reported similarities with and differences to related concepts (appearance teasing, cyberbullying, trolling). We conducted qualitative analyses of the verbal definitions guided by the Grounded Theory approach and quantified the fit to existing concepts in the field of social aggression. The results show that BS is perceived as an unrepeated act in which a person expresses unsolicited, mostly negative opinions/comments about a target’s body, without necessarily intending to harm him/her. Still, the target perceives the comments as negative. BS can range from well-meant advice to malevolent insults and it can occur online and offline. Participants saw similarities between BS and appearance teasing. BS can be a tool for trolling and can evolve to cyberbullying with repetition over time. Altogether, BS is a form of social aggression that has a negative impact on individuals. The definition and classification help to investigate BS and its effects on body image and mental health in future research.
Background
Common carotid intima-media thickness (ccIMT) is an established risk marker for cardiovascular events, including myocardial infarction and stroke, which are of high public health relevance. While a higher fruit intake is generally considered beneficial for cardiovascular health, recent studies have shown that a fruit intake of > 2 portions per day may be harmful. Therefore, we tested if there is an association between categories of fruit intake and mean ccIMT.
Methods
We conducted an exploratory, non-prespecified, cross-sectional analysis of baseline values of 167 mostly middle-aged participants of a controlled lifestyle intervention, recruited from the general population in rural northwest Germany (male: n = 58; female: n = 109). Fruit intake was classified into low (<1 portion of fruit/day), intermediate (1-2 portions of fruit/day), and high (>2 portions of fruit/day). Mean ccIMT was measured in accordance with the Mannheim consensus. Between-group differences in mean ccIMT were assessed with analysis of covariance.
Results
Mean age was 57.3 ± 0.7 years (mean ± SEM). Mean fruit intake was 1.6 ± 0.1 portions/day. Average mean ccIMT was 0.679 ± 0.010 mm. There was a significant difference in mean ccIMT between subjects with low (0.676 ± 0.020 mm; n = 50), intermediate (0.653 ± 0.014 mm; n = 72), and high fruit intake (0.724 ± 0.019 mm; n = 45; p = 0.016). But this difference was attenuated when adjusting for age, sex, and homocysteine (p = 0.418).
Conclusions
We found only a non-significant association between consuming >2 portions of fruit per day and ccIMT. Thus, our study could not confirm a negative effect of fruit intake on ccIMT. Age, sex, and homocysteine may confound this association.
Key messages
Current recommendations of 2 portions of fruit per day seem adequate and do not negatively influence carotid intima-media thickness.
Future studies should address confounding of the association between fruit intake and cardiovascular risk markers.
The article explains how an “Academic Scorecard” may help to build a bridge between operational and strategic management. First, we will have a closer look at the problem of the “strategic gap”, before the basic concept of the Balanced Scorehand is explained. Then, the Academic Scorecard will be introduced and applied to the sphere of internationalisation. We illustrate how a scorecard can be developed and end with some recommendations.
The Internationalisation of Higher Education - Perspectives from the THEA Ukraine Project and Beyond
(2021)
The Ukrainian higher education system has undergone a number
of developments since Ukraine committed itself to the Bologna
Process in 2005. Internationalisation and quality assurance in higher
education have thus become two core policy issues to aid Ukraine’s
efforts in becoming a full member of the European Higher
Education Area.
Within the THEA Ukraine project (October 2019 – September 2021),
32 Ukrainian Higher Education Administrators received training
in the field of internationalisation in higher education and science
management. The participants worked on individual application
projects to foster the international orientation of their home
institutions, which are located all over Ukraine.
The implementation of this project has provided material for a
number of case study descriptions of projects undertaken in the
THEA Ukraine framework, as well as general perspectives on
internationalisation in higher education; this anthology covers
both of these aspects.
Technical and organizational steps are necessary to mitigate cyber threats and reduce risks. Human behavior is the last line of defense for many hospitals and is considered as equally important as technical security. Medical staff must be properly trained to perform such procedures. This paper presents the first qualitative, interdisciplinary research on how members of an intermediate care unit react to a cyberattack against their patient monitoring equipment. We conducted a simulation in a hospital training environment with 20 intensive care nurses. By the end of the experiment, 12 of the 20 participants realized the monitors’ incorrect behavior. We present a qualitative behavior analysis of high performing participants (HPP) and low performing participants (LPP). The HPP showed fewer signs of stress, were easier on their colleagues, and used analog systems more often than the LPP. With 40% of our participants not recognizing the attack, we see room for improvements through the use of proper tools and provision of adequate training to prepare staff for potential attacks in the future.
Introduction: Moving towards a more plant-based dietary pattern would likely be beneficial in terms of a variety of sustainability dimensions.
Methodology: We conducted a 2-year intervention study with six measurement time points (baseline, 10 weeks, 6 months, 1 year, 1½ years, 2 years) in rural northwest Germany. The intervention consisted of a lifestyle programme, and dietary recommendations were to move towards a healthy, plant-based diet. The control group received no intervention. Diet quality was assessed with the healthful plant-based diet index (hPDI).
Results: In the intervention group (n = 67), the 2-year trajectory of hPDI was significantly higher compared to control (n = 39; p 0.001; between-group difference: 5.7 (95% CI 4.0, 7.3) food portions/day; adjusted for baseline). The 2-year trajectory of meat intake was significantly lower in the intervention group (n = 79) compared to control (n = 40; p 0.001; between-group difference: -0.7 (95% CI -0.9, -0.5) portions/day; adjusted for baseline).
Conclusion: Our study confirms that plant-based nutrition education in the general population is likely to result in at least modest dietary improvements in terms of general healthfulness and meat reduction.
Professional roles, including specific skills for each role, are a step towards higher professionalism and maturity within purchasing and supply management (PSM). The global development towards increasing digitalization, Industry 4.0, globalization, and increasing attention for corporate social responsibility force change within the purchasing organizations. Here, PSM's professional roles and skills are a good starting point to manage these changes by redefining professional roles organized by specific skills and responsibilities. For this reason, based on a systematic literature review and three World Cafés with 29 purchasing professionals, this study compiles a list of Industry 4.0 professional roles and skills in PSM.
This paper uses the findings from a literature review and series of expert interviews to develop a richer and Purchasing and Supply Management (PSM) context-specific perspective of the different key techniques, tools and principles that can be used to develop gamified learning to enhance the skills required by PSM professionals in dealing with current and future challenges, such as the transformation to Industry 4.0. It also provides further details of the different stages of implementing gamified learning, which can enhance the success of any such provision.
To increase maturity within purchasing and supply management (PSM), future purchasing skills are needed based on the technological development towards Industry 4.0. Past research, eg, the work of Bals, Schulze, Kelly, and Stek (2019), started to address this issue based on literature review and interview studies. However, a detailed description of these skills is missing. Utilizing a real-time Delhi study with 45 experts within the PSM field, nine future purchasing skills have been elaborated. Identified skills connect to the maturing and emerging technologies within purchasing and provide a guideline towards Industry 4.0 in purchasing based on a human-centric perspective.
Specifying roles in purchasing and supply management in the era of Industry 4.0: A Delphi study
(2021)
New technologies and systems within the field of purchasing and supply management (PSM) call forth responsibilities and require expertise. Moving towards Industry 4.0 in purchasing, increasing attention on specialization within talent and skills, where human capital is needed to exploit the full potential of technologies. Based on an internet-based real-time Delhi study with 47 experts within the PSM field, six future purchasing roles have been defined and elaborated. These future roles connect to the maturing and emerging technologies within the purchasing field and provide a guideline to further develop towards Industry 4.0 in purchasing based on a human-centered evolutionary approach.
Identifying Start-Up Partners: Which Search Practices and Combination Strategies are Effective?
(2021)
Start-ups are an important source of novel knowledge and product ideas for incumbents. We investigate which search strategies are positively related to the successful search for start-ups. We identify search instruments and their various uses: intensive or broad; stand-alone or combinatory. Finding 11 search practices in the literature, we evaluate how these practices were used by 97 respondents from a cross-industry and cross-national sample. Our results show that searching broadly and intensively is positively related to a successful search for start-ups and to firms’ radical innovation capability. Specific tools that are positively related to search success are online contacts, desk research, external scouting partners, and start-up pitch events. Decision tree analysis provides effective combinations of search practices that innovation managers and purchasing managers can use. Employing these search practice combinations, we make incumbents aware of the routines used in distant knowledge search. These practices are dynamic capabilities that help them to remain successful in high-velocity markets. In identifying these search practices, we contribute to the literature on innovation routines and dynamic capability research.
Purpose
Procurement professionals widely use purchasing portfolio models to tailor purchasing strategies to different product groups’ needs. However, the application of these approaches in hospitals and the impact of a pandemic shock remain largely unknown. This paper aims to assess hospital purchasers’ procurement strategies during the COVID-19 pandemic, the effects of factor-market rivalry (FMR) on strategies and the effectiveness of purchasing portfolio categorizations in this situation.
Design/methodology/approach
This qualitative study of hospital purchasing in the Netherlands is supported by secondary data from official government publications. Semi-structured interviews were conducted with 13 hospital purchasers at large hospitals. An interpretative approach is used to analyze the interviews and present the results.
Findings
The findings reveal that product scarcity forces purchasers to treat them as (temporary) bottleneck items at the hospital level. The strategies adopted largely aligned with expected behavior based on Kraljic’s commodity management model. Adding the FMR perspective to the model helped to further cluster crisis strategies into meaningful categories. Besides inventory management, increasing supply, reducing demand and increasing resource coordination were the other common strategies. An important finding is that purchasers and governments serve as gatekeepers in channeling FMR, thereby reducing potential harmful competition between and within hospitals.
Social implications
The devastating experience of the COVID-19 pandemic is unveiling critical weaknesses of public health-care provision in times of crisis. This study assesses the strategies hospital purchasers apply to counteract shortages in the supply chain. The findings of this study emphasize the importance of gatekeepers in times of crisis and present strategies purchasers can take to assure the supply of resources.
Originality/value
No research has been conducted on purchasing portfolio models and FMR implications for hospitals during pandemics. Therefore, the authors offer several insights: increasing the supply risk creates temporary bottleneck strategies, letting purchasers adopt a short-term perspective and emphasizing the high mobility of commodities in the Kraljic commodity matrix. Additionally, despite more collaboration uncovered in other studies regarding COVID-19, strong rivalry arose at the beginning of the pandemic, leading to increased competition and less collaboration. Given such increased FMR, procurement managers and governments become important gatekeepers to balance resource allocation during pandemics both within and between hospitals.
Food-processing companies are controlled by societal influences and economic interests, but their efforts with regard to reducing food loss and waste are very different. This qualitative study aims to identify basic recommendations of good practice for the food-processing industry in order to prevent and handle food loss and waste. For this purpose, a comprehensive literature review was conducted in the field of food waste prevention and data was collected from thirteen German companies. The findings summarize the recommendations of good practice, which cover the entire supply chain from supplier to consumer and beyond. The analysis showed that the participating companies are already partially aware of operational measures, even if they are applied or mentioned without a systematic approach. Furthermore, the analysis revealed that most activities relate to internal matters, like processing, employees and utilization. However, the responsibility of foodprocessing companies does not end with internal processes to reduce food waste. The results show that some companies are already aware of their responsibility to be involved along the entire supply chain. Finally, the results show that the needs of consumers and suppliers must also be considered in order to reduce food waste, in addition to direct reduction measures. This paper highlights nine important stages and 53 basic recommendations for companies to address food loss and waste in order to improve their practices.
A Curriculum on the Basis of Qualification Research / Hrsg. Ingrid Darmann-Finck, Karin Reiber
(2021)
Phenanthroline chromophore as efficient antenna for Tb3+ green luminescence: A theoretical study
(2021)
The quaternary tungstates Li3Ba2RE3(WO4)8 (RE = La-Nd, Sm-Ho) were obtained by a ceramic synthesis route and were characterized by powder and single crystal X-ray diffraction. The structures of Li3Ba2Pr3(WO4)8 and Li3Ba2Tb3(WO4)8 were refined from single crystal diffractometer data: RbLiBi2(MoO4)4 type, space group C2/c, a = 528.57(2), b = 1292.39(6), c = 1934.80(10) pm, b = 91.522(4)°, 2151 F2 values, 108 parameters for Li3Ba2Pr3(WO4)8 and a = 520.54(2), b = 1272.03(6), c = 1918.85(10) pm, b = 91.948(4)°, 2020 F2 values, 108 variables for Li3Ba2Tb3(WO4)8. Striking polyhedral building units in these tungstates are WO4 tetrahedra and LiO6 octahedra, while the mixed occupied site and the barium atoms have higher coordination numbers, i.e. RE/Li@O8 and Ba@O10. In addition to the powder quality assessment by means of reflection spectroscopy, the synthesized samples were studied for their suitability as a scintillator material. Therefore, X-ray excited luminescence measurements where performed. Apart from Li3Ba2Ce3(WO4)8 and Li3Ba2Nd3(WO4)8, all compounds show strong emission under X-ray irradiation. Li3Ba2La3(WO4)8 and Li3Ba2Gd3(WO4)8 show blue CT luminescence caused by tungstate units, while the other samples show typical and multiple lines due to well known [Xe]4fn → [Xe]4fn transitions.
We report on a watt-level highly efficient europium laser operating at the 5D0→7F4 transition. It is based on the stoichiometric KEu(WO4)2 crystal. Under pumping by a green laser at 532.1 nm, the KEu(WO4)2 laser generated a maximum peak output power of 1.11 W at ∼703nm with a slope efficiency of 43.2% and a linear polarization (????‖????????). A laser threshold as low as 64 mW was achieved. True continuous-wave operation was demonstrated. The polarized emission properties of monoclinic KEu(WO4)2 were determined.
What sparks academic engagement with society? A comparison of incentives appealing to motives
(2021)
Due to the increasing connectivity of modern vehicles, collected data is no longer only stored in the vehicle itself but also transmitted to car manufacturers and vehicle assistant apps. This development opens up new possibilities for digital forensics in criminal investigations involving modern vehicles. This paper deals with the digital forensic analysis of vehicle assistant apps of eight car manufacturers. We reconstruct the driver’s activities based on the data stored on the smartphones and in the manufacturer’s backend.
For this purpose, data of the Android and iOS apps of the car manufacturers Audi, BMW, Ford, Mercedes, Opel, Seat, Tesla, and Volkswagen were extracted from the smartphone and examined using digital forensic methods following forensics guidelines. Additionally, manufacturer data was retrieved using Subject Access Requests. Using the extensive data gathered, we reconstruct trips and refueling processes, determine parking positions and duration, and track the locking and unlocking of the vehicle.
Our findings show that the digital forensic investigation of smartphone applications is a useful addition to vehicle forensics and should therefore be taken into account in the strategic preparation of future digital forensic investigations.
Modern implantable cardiologic devices communicate via radio frequency techniques and nearby gateways to a backend server on the internet. Those implanted devices, gateways, and servers form an ecosystem of proprietary hardware and protocols that process sensitive medical data and is often vital for patients’ health.
This paper analyzes the security of this Ecosystem, from technical gateway aspects, via the programmer, to configure the implanted device, up to the processing of personal medical data from large cardiological device producers. Based on a real-world attacker model, we evaluated different devices and found several severe vulnerabilities. Furthermore, we could purchase a fully functional programmer for implantable cardiological devices, allowing us to re-program such devices or even induce electric shocks on untampered implanted devices.
Additionally, we sent several Art. 15 and Art. 20 GDPR inquiries to manufacturers of implantable cardiologic devices, revealing non-conforming processes and a lack of awareness about patients’ rights and companies’ obligations. This, and the fact that many vulnerabilities are still to be found after many vulnerability disclosures in recent years, present a worrying security state of the whole ecosystem.
The PosiThera project focuses on the management of chronic wounds, which is multi-professional and multi-disciplinary. For this context, a software prototype was developed in the project, which is intended to support medical and nursing staff with the assistance of artificial intelligence. In accordance with the user-centred design, national workshops were held at the beginning of the project with the involvement of domain experts in wound care in order to identify requirements and use cases of IT systems in wound care, with a focus on AI. In this study, the focus was on involving nursing and nursing science staff in testing the software prototype to gain insights into its functionality and usability. The overarching goal of the iterative testing and adaptation process is to further develop the prototype in a way that is close to care.
In order to anchor the guiding idea of sustainable development in vocational education and training structurally corresponding competences must be identified and
taught within the framework of vocational education and training (VET).
This presentation presents the idea behind VET and a model for describing sustainability-related competences in food processing professions.
Africa recognised the potential of digital transformation before the COVID-19 pandemic. With the Digital Transformation Strategy, the continent committed itself to support this change in line with the Agenda 2063: The Africa We Want with focus on investment in Information and Communication Technology (ICT) , the promotion of the digital economy and the adoption of open and distance learning in tertiary education. However, the pandemic has given renewed impetus for digital change in higher education. The shutdowns of educational institutions brought about by COVID-19 have demonstrated that teaching and learning can be re-designed and educational institutions developed further, with the sprouting of collaborations in and across countries and continents. The drive for digital transformation, which is now gaining momentum throughout higher education institutions worldwide, is of major significance in giving renewed stimulus to one of the boldest agendas that have been adopted by mankind, the SDGs, the United Nations' Sustainable Development Goals.
Teaching and learning in international and thus intercultural contexts places special demands on the conception of trainings. The same holds true for online or distance learning. Taken together, both factors – training in an intercultural and online context – pose specific didactic and technical challenges. Against the background of the COVID-19 pandemic all international training programmes under the umbrella of the Higher Education Management Programme at FH Münster –University of Applied Sciences had to be held online. In the article on hand we share our experiences with online training for actors in the higher education area from developing and emerging countries and discuss its specific demands along the lines of common criteria for effective learning.
ALPACA: Application Layer Protocol Confusion - Analyzing and Mitigating Cracks in TLS Authentication
(2021)
TLS is one of today's most widely used and best-analyzed encryption technologies. However, for historical reasons, TLS for email protocols is often not used directly but negotiated via STARTTLS. This additional negotiation adds complexity and was prone to security vulnerabilities such as naive STARTTLS stripping or command injection attacks in the past.
We perform the first structured analysis of STARTTLS in SMTP, POP3, and IMAP and introduce EAST, a semi-automatic testing toolkit with more than 100 test cases covering a wide range of variants of STARTTLS stripping, command and response injections, tampering attacks, and UI spoofing attacks for email protocols. Our analysis focuses on the confidentiality and integrity of email submission (email client to SMTP server) and email retrieval (email client to POP3 or IMAP server). While some of our findings are also relevant for email transport (from one SMTP server to another), the security implications in email submission and retrieval are more critical because these connections involve not only individual email messages but also user credentials that allow access to a user's email archive.
We used EAST to analyze 28 email clients and 23 servers. In total, we reported over 40 STARTTLS issues, some of which allow mailbox spoofing, credential stealing, and even the hosting of HTTPS with a cross-protocol attack on IMAP. We conducted an Internet-wide scan for the particularly dangerous command injection attack and found that 320.000 email servers (2% of all email servers) are affected. Surprisingly, several clients were vulnerable to STARTTLS stripping attacks. In total, only 3 out of 28 clients did not show any STARTTLS-specific security issues. Even though the command injection attack received multiple CVEs in the past, EAST detected eight new instances of this problem. In total, only 7 out of 23 tested servers were never affected by this issue. We conclude that STARTTLS is error-prone to implement, under-specified in the standards, and should be avoided.
(1) Background: Schools report a high number of schoolchildren with poor attention and hyperactive behavior, with 5% being diagnosed with attention deficit/hyperactivity disorder (ADHD). This causes specific problems during homework and classroom times, and the extension of all-day schooling in German primary schools makes this a challenge for support staff working in the after-school programs. Such staff have a very wide variety of qualifications, ranging from no formal teacher training to full teaching qualifications. (2) Methods: This study documents the knowledge of 196 support staff working in all-day primary schools about ADHD, and their subjective view of whether they feel competent with regard to homework situations in general and ADHD in particular. (3) Results: Those with an educational background have significantly more knowledge than those without such a background, staff feel less prepared to supervise children with ADHD, and there is a small but significant correlation here with knowledge about ADHD. (4) Conclusions: The importance of trained pedagogical staff in the supervision of children with concentration problems is emphasized.
Background. Ketone bodies are a highly relevant topic in nutrition and medicine. -e influence of medium-chain triglycerides (MCT) on ketogenesis is well known and has been successfully used in ketogenic diets for many years. Nevertheless, the effects of MCTs and coconut oil on the production of ketone bodies have only partially been investigated. Furthermore, the increased mobilisation of free fatty acids and release of catabolic hormones by caffeine suggest an influence of caffeine on ketogenesis.
Methods. In a controlled, double-blind intervention study, seven young healthy subjects received 10mL of tricaprylin (C8), tricaprin (C10), C8/C10 (50% C8, 50% C10), or coconut oil with or without 150 mg of caffeine, in 250mL of decaffeinated coffee, over ten interventions. At baseline and after every 40 minutes, for 4 h, ßHB and glucose in capillary blood as well as caffeine in saliva were measured. Furthermore, questionnaires were used to survey sensory properties, side effects, and awareness of hunger and satiety. Results. -e interventions with caffeine caused an increase in ßHB levels—in particular, the interventions with C8 highly impacted ketogenesis. -e effect decreased with increased chain lengths. All interventions showed a continuous increase in hunger and diminishing satiety. Mild side effects (total � 12) occurred during the interventions. Conclusions. -e present study demonstrated an influence of caffeine and MCTon ketogenesis. -eaddition of caffeine showed an additive effect on the ketogenic potential of MCT and coconut oil. C8 showed the highest ketogenicity.
The effects of different unsteady ventilation strategies on flow-structures in a room are investigated and compared to steady ventilation with the same mean exchange rate. For this, whole-field optical flow measurements were executed by means of a particle image velocimetry system (PIV) in a Reynolds-scaled room model in water. In a first series of experiments, sinusoidal varied supply flows with different frequencies were analysed; two equally supplied simple nozzles in the ceiling were used as inlets. The setup was validated by comparing jet velocities with literature values.
Typically, room airflows are investigated with punctual measurement techniques (e.g.
anemometers), which have an impact on the flow field, or with smoke gas experiments. By using PIV, the flow can be analysed without any influence of sensors or stands/traverses and whole-field measurement data with high spatial resolution and detailed information on the flow field can be collected.
Local and time-averaged velocities and standard deviations were calculated for all scenarios. Unsteady conditions were created by a sinusoidal variation of the supply flow rate with frequencies between 0.025 1/s and 0.050 1/s, an offset of about 1.1 m3/h and an amplitude of about ±1.0 m3/h, which leads to a mean exchange rate of 3.5 1/h. Although averaged velocity fields only show slight differences between steady and unsteady conditions, single pictures vary widely. First effects of unsteady ventilation on flow structures can be recognized. Steady structures are destroyed, and velocities change rapidly.
The inlets will be changed to small-scale ceiling-diffusors in future experiments to create more realistic room ventilation conditions. Other types of unsteady supply flows will be implemented, and parameters will be varied. The results of the PIV-measurements can be used to validate CFD simulations and to derive dimensioning rules and application recommendations.
This paper presents the results of the technology development project “Enabling Technologies for Piezo-Based Deformable Mirrors in Active Optics Correction Chains” conducted by OHB System AG together with its partner Münster University of Applied Sciences (MUAS). The project was funded by ESA within their General Support Technology Programme
(GSTP).
We address in this paper mainly the definition, flow-down and verification of the requirements for the Deformable Mirror (DM). The requirements were derived from a set of real space mission applications. The deformation of the mirror is performed by piezo-ceramic actuators in an unimorph configuration. The finally developed DM is able produce Zernike modes with a stroke of several tens of µm over a clear optical aperture of 50 mm in diameter. It underwent successfully a full environmental qualification campaign including thermal cycling, shock- and vibration testing, as well as exposure to
proton and γ–ray radiation. Thermal and performance tests were performed in the temperature range from 100 K to 300 K.
Furthermore, the DM sustained all vibration (random 17.8 g RMS and sinus) and shock (300 g) testing. Thereby all criticalities which were identified a previous study have been overcome successfully.
A Technology Readiness Level (TRL) of 5 is reached, as the component has been validated in relevant environment. Based on the high level of maturity, this deformable mirror is now ready for the incorporation in future flight instruments. The achieved TRL of 5 is sufficient for the status of a PDR at payload level and gives thus a very good basis for all kinds of potential B2, C/D payload developments.
We present our latest results on a refined unimorph deformable mirror which was developed in the frame of the ESA GSTP activity ”Enabling Technologies for Piezo-Based Deformable Mirrors in Active Optics Correction Chains”. The identified baseline concept with the soft piezoceramic material PIC151 successfully sustained all vibration requirements (17.8 gRMS random and 20 g sine) and shock testing (300 g SRS). We cover the mirror design development which reduces the stress in the brittle piezo-ceramic by 90 % compared to the design from
a former GSTP activity. We briefly address the optical characterization of the deformable mirror, namely the achieved Zernike amplitudes as well as the unpowered surface deformation (1.7 µm) and active flattening (12.3 nmRMS). The mirror produces low-order Zernike modes with a stroke of several tens of micrometer over a correction aperture of 50 mm, which makes the mirror a versatile tool for space telescopes.
Different from negatively charged CuInS2 (CIS) based quantum dots (QDs), positively charged QDs are difficult to obtain in good optical quality, but are desirable for certain applications. We herein present a general synthesis strategy that allows for a universal surface modification of ternary CIS based QDs with thiol containing ligands.
The idea behind the synthesis design is, to apply a ZnS shell first for passivating and protecting the core QDs, and then add a second ZnS shell for the functionalization via ligand exchange. Whereby easy ligand exchange with thiolated molecules is systematically set up, by using a weak bonding amine ligand for the second shell. Molecules with various terminal groups were used to functionalize the nanoparticles and stabilize them in different media making any surface charge and polarity accessible. Surface defect chemistry seemed to play an important role in our synthesis strategy, therefore to gain a deeper understanding how these defect sites can alter the electronic structure of core/shell nanoparticles theoretical calculations based on density functional theory were performed, whilst structural, colloidal and optical properties were characterized experimentally (by dynamic light scattering, x-ray diffraction, infrared spectroscopy, zeta potential, absorption- and (time resolved) photoluminescence
measurements).
Process-Driven Applications flourish through the interaction between an executable BPMN process model, human tasks, and external software services. All these components operate on shared process data, so it is even more important to check the correct data flow. However, data flow is in most cases not explicitly defined but hidden in model elements, form declarations, and program code. This paper elaborates on data-flow anomalies acting as indicators for potential errors and how such anomalies can be uncovered despite implicit and hidden data-flow definitions. By considering an integrated view, it goes beyond other approaches which are restricted to separate data-flow analysis of either process model or source code. The main idea is to merge call graphs representing programmed services into a control-flow representation of the process model, to label the resulting graph with associated data operations, and to detect anomalies in that labeled graph using a dedicated data-flow analysis. The applicability of the solution is demonstrated by a prototype designed for the Camunda BPM platform.
Electrical Engineering
(2021)
In this chapter, fundamental properties of charged objects are discussed. It is shown how they may be used to design and use capacitors, resistors and inductors. Function and the usage of bipolar and MOS semiconductor devices are presented. The chapter is concluded by a discussion of DC and AC networks
The global salinity gradient power (SGP) potential is between 1650 - 2000 TWH/a and can be converted by mixing two solutions with different salinities. The harnessing of SGP for conversion into power can be accomplished by means of pressure retarded osmosis (PRO) and reverse electrodialysis (RED). PRO and RED are membrane-based technologies and have different working principles. PRO uses a semipermeable membrane to seperate a concentrated salt solution from a diluted solution. The diluted solution flows through the semipermeable membrane towards the concentrated solution, which increases the pressure within the concentrated solution chamber. The pressure is balanced by a turbine and electricity is generated. RED uses the transport of ions through cation and anion exchange membranes. The chambers between the membranes are alternately filled with a concentrated and diluted solution. The salinity gradient difference is the driving force in transporting ions that results in an electric potential, which is then converted to electricity. The comparison shows that there are two different fields of application for PRO and RED. PRO is especially suitable at extracting salinity energy from large concentration differences. In contrast, RED are not effect by increasing concentration differences. So PRO are supposed to focus on applications with brines or waste water and RED on applications with river water and seawater. Moreover, just a few measured values from processes under real conditions are available, which makes it difficult to compare PRO and RED.
The impact of hydro-power plants on the ecosystem was studied with focus on the fish mortality and types of damage for many years. The fish mortality have a wide range of causes. Types of damage can be different and are caused by different parts of the power plant. The most dangerous part of the system are the fast moving turbine blades. They can cause blade strike and barotrauma due to the high speeds. Different types of turbines were developed for a better survival rate. Five different types of different research groups and manufacturers are presented in this paper. By considering those newly developed turbine designs, a fish survival rate from 96 % to 100 % is achieved.
The first oscillating water column was invented in 1940. In the past decades the need of wave energy systems has significantly increased. This article quickly describes the Wells turbine and possibilities to enhance its performance and should answer the question: what are the design parameters that can be optimized?
Furthermore it gives a small outlook about the history of oscillating Water Columns.
There are many hydropower turbines for low heads or low flows on a small scale. Many technologies are unsuitable for developing countries because equipment or materials are limited, high-tech machines are to expensive or spare parts are not readily available. This review combines currently available technologies with the requirements of developing countries in small, micro and pico hydropower. In small hydropower a propeller turbine from Thailand has a high efficiency of 70 to 80 percent at calculated production costs of around $ 513 per kW. Pumps as turbines are suitable for developing countries in micro hydropower due to readily availability, low price and an large number of standard sizes. In pico-scale, a low-cost Turgo wheel can be made of spoons for $ 48 and yields acceptable values in comparison to a 3D printed Pelton wheel for $ 822. While the Turgo wheel is suitable for high heads, a homemade siphon turbine can be used for low heads. The siphon turbine generates up to 200 W, is made of materials that are available anywhere in the world, and costs less than $ 50.
Self-build small wind turbines are used for rural electrification in the developed and developing world as well as for educational purposes. To give an overview about self-build small wind turbines a systematic literature review was conducted. The identified literature deals with two different vertical and horizontal axis turbine designs. The vertical axis turbines are both prototypes while one of the horizontal axis designs, the design by Piggott is widely used in rural electrification projects. Different papers dealing with the optimization of the Piggott design exist. In retrospect the conduction of a holistic review was not possible due to limited resources and length of this review. Nevertheless it can give a quick overview and a starting point for further research.
Despite their important role in our energy system, common wind turbines have some disadvantages. Mainly, those disadvantages are connected to the intermediate conversion of wind energy in rotational energy. The resulting effects include maintenance costs and social acceptance problems. There are different technological approaches, that convert wind energy to electrical energy without its conversion to kinetic energy. As one of those technologies, the electrostatic wind energy conversion is to be discussed in this article. For this discussion, the historical development of this technology is presented. There are three important projects which will be presented to explain the technology and its different technological approaches. Those projects are the WPG, the EWICON and the SWET. Furthermore the results of those different experimental projects are collected and analyzed. On the basis of this analysis it is discussed, whether or not the electrostatic wind energy conversion could be of importance in a future energy system. Therefore the technology is set in relation to modern wind turbines. Also, important factors that influence the efficiency and energy output of those systems are outlined for further research. Due to different technological approaches a suggestion is made for the most promising system setting.
Because of the rapid expansion and widespread application of wind energy the overall environmental impacts of wind power plants have increased as well. For the further development of wind power, methods to lessen the adverse effects wind power has on avian populations have to be implemented. This review aims to find effective methods to reduce avian collision rates with wind turbines and that therefore can reduce bird fatality rates.
For the assessment the different mitigation methods, for which concrete data was found, are compared with each other regarding the hypothetical effort of implementation and effectiveness in reducing avian collision rates with wind turbines.
These methods are:
(a) Coloring of rotor blades
(b) Coloring of the tower base
(c) Ultraviolet/violet lightning
(d) Temporary shut-down of wind turbines
(e) Auditory warning signals
(f) Repowering
All of the mentioned methods report influence on reducing avian collision rates or at least the behavior of birds in flight.
This review found the following three methods to be most effective:
(a) Coloring of rotor blades
(b) Temporary shut-downs of wind turbines
(c) Repowering
The most effective method to reduce avian collision rates at horizontal axis wind turbines is to paint one of the rotor blades black and consequently increasing the visibility of the rotor blades. The presented study reports 71,9 percent reduction of found carcasses of birds at the treated turbines. For this method the effort of implementation is low while the effectiveness is high.
The effectiveness of the found mitigation methods has been proven and they are suited for application. The method of using lightning or sound fields require more testing to determine their effectiveness. Another topic for research could be how different mitigation methods interact with each other. Is there a significant advantage to be had if multiple mitigation methods are applied at the same wind power plant or turbine? Furthermore the environmental impacts of wind turbines are not limited to birds. Other animals like bats are affected too and might require different methods of mitigation.
Wind energy has steadily gained importance in the generation of renewable energy over the last 25 years. A wind turbine has an average life expectancy of about 25 years. After that, thermoplastic composite materials from the rotors, among other things, accumulate and have to be recycled. Previous methods, such as landfilling, incineration and pyrolysis, have not yet proven to be effective in terms of the circular economy because the recycled material cannot be reused for equivalent products. The use of thermoplastic materials can be a sensible alternative, as thermoplastic resins can be recycled almost without loss of value due to their properties. Recycling of fibreglass is also possible with less loss of stiffness. In the future, it will be crucial to scale up thermoplastic rotor blades and create a market for the recycled material.
Wind energy conversion systems have attracted considerable attention as a renewable energy source due to depleting fossil fuel reserves and environmental concerns as a direct consequence of using fossil fuel and nuclear energy sources. The increasing number of wind turbines increases the interest in efficient systems. The power output of a wind energy conversion system depends on the accuracy of the maximum power tracking system, as wind speed changes constantly throughout the day. Maximum power point tracking systems that do not require mechanical sensors to measure the wind speed offer several advantages over systems using mechanical sensors. In this paper four different approaches that do not use mechanical sensors to measure the wind speed will be presented; the assets and drawbacks of these systems are highlighted, and afterwards the examined algorithms will be compared based on different characteristics. Finally, based on the analysis, an evaluation is made as to which of the presented algorithms is the most promising.
Assessment of noise mitigation measures during pile driving of larger offshore wind foundations
(2021)
Wind energy is an important source of electricity generation, but the construction of offshore wind foundations causes high underwater sound pressure, harming marine life. In this context limiting values for underwater noise emissions were set to protect the marine flora and fauna. Therefore, noise mitigation measures during pile driving are mandatory to comply with these limits. Current development in the wind industry lead to increasing wind turbine sizes, requiring a larger pile diameter, which leads to higher underwater noise emissions. As a result, the state of the art noise mitigation systems might not be sufficient and a combination of different technologies is necessary. This article focuses on the issue of noise mitigation during pile driving with respect to large pile sizes. First, the most tested and proven noise mitigation techniques (big bubble curtain, hydro sound damper, and IHC-noise mitigation system) are described, following an analysis of noise reduction measurements in applications at different offshore wind farm projects. In the end the suitability of current noise mitigation systems for large monopiles is evaluated, regarding their effectiveness and practicability.
Floating offshore wind (FOW) holds the key to 80 % of the total offshore wind resources, located in waters of 60 m and deeper in European seas, where traditional bottom-fixed offshore wind (BFOW) is not economically attractive.
Many problems affecting floating offshore wind turbines (FOWT) were quickly overcome based on previous experience with floating oil rigs and bottom-fixed offshore wind. However, this technology is still young and there are still many challenges to overcome.
This paper shows that electrical failures are amongst the most significant errors of FOWT. The most common cause was corrosion. It is also stated that the control system is most often affected, and that the Generator is frequently involved. Material corrosion is also the key factor when it comes to the most common overall reason for failures.
A particular attention must be paid to mooring line fracture. Mooring lines are especially vulnerable to extreme sea conditions and the resulting fatigue, corrosion, impact damage, and further risks.
It must be stated that the primary challenge is that of economics. Over time technological costs will decline making FOW more competitive and hence attractive for greater depth.
Originally this article was supposed to be a comparison between the technological differences of bottom-fixed offshore wind turbines (BOWT) and floating offshore wind turbines (FOWT). However, several authors already contributed to this topic and came to the conclusion that the higher levelized costs of energy (LCOE) prevent FOWTs from successfully entering the energy market. Multiple sources seem to agree on this conclusion but often do not provide the reader with further information regarding the LCOE. This is the reason why this article understands itself as an in depth cost comparison between BOWTs and FOWTs. For this purpose, individual LCOE are calculated for the upcoming FOWT technologies such as spar-buoy (SPAR), tension-leg platform (TLP) and semi-submersible platform (semi-sub) as well as conventional BOWTs using the wind turbines hours of full utilization (HOFU). The resulting functions are visualized graphically in order to determine break-even points between BOWTs and FOWTs. Finally, a sensitivity analysis is carried out to determine the influence of the weighted average costs of capital (WACC).
With floating offshore wind turbines, new sources of wind energy can be used, which cannot be tapped into by bottom-fixed wind turbine systems. However, due to their design, they experience additional motion caused by wind and wave loads. The motions that are induced into the system have an oscillating course. This affects the aerodynamic properties of the wind turbine and leads to changes in the thrust force and power output of floating wind turbines compared to bottom-fixed wind turbines. Furthermore, the motions lead to an earlier breakdown of the helical wake structure behind the wind turbine and moreover lead to a decreased reliability of the rotor blades. Differences in the effects of wind and wave loads on the aerodynamic performance of floating offshore wind turbines supported by different platform systems were found.
Effect of a 6-Month Controlled Lifestyle Intervention on Common Carotid Intima-Media Thickness
(2021)
Laser shock peening is a new and important surface treatment technique that can enhance the mechanical properties of metal materials. Normally, the nanosecond laser with pulse-width between 5 ns and 20 ns is used to induce a high-pressure shock wave that can generate plastic deformation in the top layer of metals. The femtosecond laser shock peening in the air has been studied recently, which can induce higher pressure shock wave than that of traditional nanosecond laser shock peening in a very short time. The NiTi alloy is processed by femtosecond laser shock peening, then a nanoindentation device is used to measure its surface hardness and residual stress. The hardness results of NiTi alloy before and after treatment show that the femtosecond laser shock peening can increase the hardness of NiTi alloy, which also shows that the femtosecond laser can be used to perform laser shock peening on NiTi alloy without coating.
Blockchain is seen as having high potential for the healthcare industry. In addition to the technological properties of the blockchain, crowd funding via Initial Coin Offerings (ICOs) has also become a significant way of financing for start-ups in the healthcare industry. These ICOs are significantly different from familiar funding channels and therefore require intensive consideration of the factors relevant to success. Numerous papers have explored the success factors, but without considering the specifics of the healthcare industry. We fill this research gap and, based on hypotheses and a quantitative analysis of freely available data, show the factors relevant to the healthcare industry for a successful ICO. As a result, we show clear differences to the previously known success factors for ICOs and thus prove that the success factors of ICOs require an industry-specific consideration. Start-ups receive valuable advice on how to design a successful ICO. For the scientific community, there are starting points for further research into the success of ICOs.
Purpose:
Industrial revolutions have been induced by technological advances, but fundamentally changed business and society. To gain a comprehensive understanding of the fourth industrial revolution (I4.0) and derive guidelines for business strategy, it is, therefore, necessary to explore it as a multi-facet phenomenon. Most literature on I4.0, however, takes up a predominantly technical view. This paper aims to report on a project discussing a holistic view on I4.0 and its implications, covering technology, business, society and people.
Design/methodology/approach:
Two consecutive group discussions in form of academic world cafés have been conducted. The first workshop gathered multi-disciplinary experts from academia, whose results were further validated in a subsequent workshop including industry representatives. A voting procedure was used to capture participants perspectives.
Findings:
The paper develops a holistic I4.0 vision, focusing on five core technologies, their business potential, societal requests and people implications. Based on the model a checklist has been developed, which firms can use a tool to analyze their firm’s situation and draft their industry 4.0 business strategy.
Originality/value:
Rather than focusing on technology alone – which by itself is unlikely to make up for a revolution – this research integrates the entire system. In this way, a tool-set for strategy design results.
This work deals with the spectroscopic properties of praseodymium doped single crystalline lutetium aluminum garnet (LuAG:Pr3+). A special focus was set on temperature- and time-dependent spectroscopy. Beyond the well-known down-conversion luminescence of LuAG:Pr3+, also UV-A/B up-conversion luminescence under excitation with a 488 nm laser was thoroughly investigated. Furthermore, the results of the spectroscopic investigations on the single crystalline material were supplemented and compared with measurements on a microscale powder sample.
In addition, to the spectroscopic investigations, mechanistic considerations are presented to obtain a closer look at the up-conversion process in LuAG:Pr3+. We promote the thesis of a temperature-dependent energy transfer up-conversion mechanism.
Cross-saturation of the gain media in intra-cavity pumped lasers leads to complex dynamics of the laser power. We present experimental results and a detailed theoretical analysis of this nonlinear dynamics for an intra-cavity pumped Yb:YAG thin-disk laser in the framework of a rate-equation model. The gain medium of this laser is residing in the resonator of a conventional, diode-pumped Yb:YAG thin-disk laser. Continuous-wave operation, periodic pulse trains, and chaotic fluctuations of the optical power of both lasers were observed. The dynamics is not driven by external perturbations but arises naturally in this laser system. Further examination revealed that these modes of operation can be controlled by the resonator length of the diode-pumped laser but that the system can also show hysteresis and multi-stability.
Progress in materials development is often paced by the time required to produce and evaluate a large number of alloys with different chemical compositions. This applies especially to refractory high-entropy alloys (RHEAs), which are difficult to synthesize and process by conventional methods. To evaluate a possible way to accelerate the process, high-throughput laser metal deposition was used in this work to prepare a quinary RHEA, TiZrNbHfTa, as well as its quaternary and ternary subsystems by in-situ alloying of elemental powders. Compositionally graded variants of the quinary RHEA were also analyzed. Our results show that the influence of various parameters such as powder shape and purity, alloy composition, and especially the solidification range, on the processability, microstructure, porosity, and mechanical properties can be investigated rapidly. The strength of these alloys was mainly affected by the oxygen and nitrogen contents of the starting powders, while substitutional solid solution strengthening played a minor role.