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Purpose. Experience suggests that a loss of trust may occur on both sides of the merger and acquisition (M&A) equation – acquirer and acquiree – though the latter is more generally considered the most affected. The purpose of this paper is to explore how a loss of trust during the M&A process in family firms can be avoided. An acquisition potentially triggers a loss of trust in the workplace and, as a result, a loss of productivity thereby causing the merged business to totter. Moreover, trust in a firm’s owner tends to be a key driver in merging family firms.
Design/methodology/approach. The authors investigated an expanding German family firm that recently acquired other family firms. They conducted in-depth interviews on all hierarchical levels in both the acquiring and the acquired firm. These cases are taken from a wider study of acquiring family firms completed in 2019.
Findings. Value congruence, integrity and openness are found to enhance trust during M&As, in particular, if the new owner of a merged enterprise is also a family entrepreneur. Under certain circumstances, the trust of employees in the acquired firm’s previous owner can be transferred to the new owner.
Originality/value. This study explores how specific circumstances of family firms impacts organizational trust in M&A processes. The developed framework helps family firms to use characteristics of their specific nature as an asset to maintain their employees’ organizational trust before, during and even after M&As.
About 75% of the world's energy consumption takes place in cities. Although their large energy consumption attracts a large number of research projects, only a small fraction of them deal with approaches to model energy systems of city districts. These are particularly complex due to the existence of multiple energy sectors (multi-energy systems, MES), different consumption sectors (mixed-use), and different stakeholders who have many different interests.
This contribution is a review of the characteristics of energy system models and existing modeling tools. It evaluates current studies and identifies typical characteristics of models designed to optimize MES in mixed-use districts. These models operate at a temporal resolution of at least 1 h, follow either bottom-up or hybrid analytical approaches and make use of mixed-integer programming, linear or dynamic.
These characteristics were then used to analyze minimum requirements for existing modeling tools. Thirteen of 145 tools included in the study turned out to be suitable for optimizing MES in mixed-use districts. Other tools where either created for other fields of application (12), do not include any methodology of optimization (39), are not suitable to cover city districts as a geographical domain (44), do not include enough energy or demand sectors (20), or operate at a too coarse temporal resolution (17). If additional requirements are imposed, e.g. the applicability of non-financial assessment criteria and open source availability, only two tools remain.
Overall it can be stated that there are very few modeling tools suitable for the optimization of MES in mixed-use districts.
Berufliche Bildung für Menschen mit Beeinträchtigungen im Spannungsfeld von Ausgrenzung und Teilhabe
(2021)
Male juveniles in segregated poor neighbourhoods are at increased risk of violence. The code of the street approach is commonly used to understand the context informing street violence in such marginalized spaces, but the concept is mainly used in Western countries, especially in African American communities in the US. This study investigates whether the code of the street is also applicable to the largest Roma neighbourhood in Europe, located in Bulgaria, through guided interviews with male juveniles. The results show that some elements of the code work are applicable in this space, but clear differences also emerge. These findings affect the generalizability of the approach and the understanding of street violence.
Forschungsethische und datenschutzrechtliche Aspekte der informierten Einwilligung als Audioaufnahme
(2021)
Angela Benner und Julian Löhe gehen der Frage nach, wie eine informierte Einwilligung
mit älteren Menschen dialogorientiert gestaltet und auch entsprechend dokumentiert werden kann, wenn sich die Schriftform einer Einwilligungserklärung
als hinderlich erweist. Auf der Grundlage einer qualitativen Interviewstudie
zum Thema Tod und Sterben diskutieren sie forschungspraktische Herausforderungen
im Hinblick auf Vertraulichkeit und Datenschutz und die Möglichkeit einer
Audioaufzeichnung von Einwilligungsgesprächen.
Rund 75 % des weltweiten Energieverbrauchs findet innerhalb urbaner Energiesysteme statt. Solche Systeme beinhalten mehrere Energiesektoren (Elektrizität, Wärme, Kälte, …), Verbrauchssektoren (Wohnen, Gewerbe, Industrie, Landwirtschaft, Mobilität, …) und Interessensgruppen und sind deshalb besonders komplex. Durch den Einsatz von Methoden der Energiesystemmodellierung können diese komplexen Systeme simuliert, analysiert und optimiert werden. Mit Simulationsmodellen können Kosten, Emissionen und verschiedene andere Systemparameter prognostiziert werden. Mithilfe von Optimierungsalgorithmen können Technologien miteinander verglichen, Anlagen dimensioniert und Betriebsweisen optimiert werden. Die Erkenntnisse aus Energiesystemmodellen können zur Einhaltung verschiedener politischer und sozialer Ziele, wie beispielsweise die Reduktion von Treibhausgasemissionen, der Bedarf nach kostengünstiger Energieversorgung oder auch die Stärkung der regionalen Wirtschaft, beitragen.
Im Projekt R2Q werden Ansätze der Energiesystemmodellierung für den Einsatz in der Planung urbaner Energiesysteme aufgearbeitet, angepasst und für städteplanerische Prozesse verfügbar gemacht. In ersten Modelldurchläufen für ein Testgebiet in Herne konnte durch die Kombination verschiedener Technologien eine rechnerische Minimierung der monetären Kosten um 19 % bei gleichzeitiger Reduktion der CO2-Emissionen um 36 % ermittelt werden. Durch ein emissionsoptimiertes Szenario können die CO2-Emissionen um 47 % reduziert werden, was jedoch mit einer Steigerung der Kosten um 29 % einhergeht.
In einvernehmlich nicht monogamen Beziehungen (ENMB) sind Menschen mit mehr als einer Person in einer (sexuellen und/oder emotionalen) Intimbeziehung verbunden. Vermehrt nehmen Personen, die in ENMB leben (wollen), psychosoziale Angebote in Anspruch. Damit Berater*innen angemessen auf deren Beratungsanliegen reagieren können, werden konkrete Empfehlungen für die therapeutische Arbeit formuliert. Die Empfehlungen basieren auf veröffentlichten Fallstudien, die bisher fast ausschließlich in englischer Sprache vorliegen, sowie der Beratungspraxis des Autors. Dadurch soll ein Beitrag zu einer besseren psychosozialen Versorgung von Menschen geleistet werden, die einvernehmlich nicht monogam leben (wollen).
Jahrbuch Nachhaltige Ökonomie 2020/2021 - Im Brennpunkt: Nachhaltiges Wirtschaften und Innovationen
(2021)
Marktwirtschaftliche Systeme hatten in den letzten Jahrhunderten viele Erfolge zu verzeichnen: Es konnten immer mehr Menschen ernährt werden und die absolute Armut ist weltweit zurückgegangen. Allerdings sind mit unserer Wirtschaftsweise auch vielfältige Probleme entstanden, die in Bezug auf eine nachhaltige Entwicklung in eine komplett falsche Richtung führen. Exponentielles Wirtschaftswachstum ohne Beachtung der natürlichen Tragfähigkeit unserer Erde stößt immer offensichtlicher an seine Grenzen. Während das Thema erst jetzt in der Mitte der Gesellschaft ankommt, wird die akademische Debatte über alternative Wirtschafts-systeme, in denen die Wirtschaft entweder selektiv oder weniger wächst, seit ca. 50 Jahren geführt. Sie soll im folgenden Beitrag anhand ausgewählter Ansätze dargestellt und unter dem Blickwinkel der Nachhaltigen Ökonomie und ihrer Umsetzbarkeit kritisch gewürdigt werden.
Die Kommunen in NRW verzeichnen seit mehreren Jahren eine verstärkte Zuwanderung, ob nun von EU-Bürgerinnen und Bürgern oder von Geflüchteten. Dabei ist die Zuwanderung nicht über alle Stadtteile einer Stadt gleichverteilt, sondern es bilden sich in allen kreisfreien Städten und Kreisen kleinräumige Zuwanderungsschwerpunkte heraus. Solche diversitätsgeprägten Orte sind in NRW häufig auch die ärmsten Stadtteile einer Stadt und damit Zielgebiete von Quartiersentwicklungsprogrammen. Das bedeutet, dass die Armenhäuser unserer Städte zugleich ihre Integrationsmotoren sein sollen. Dafür braucht es allerdings ein hohes Maß an integrationspolitischen Anstrengungen, in Form passgenauer Angebotslandschaften, integrierter Quartiersentwicklung und einer vorausschauenden Stadtentwicklungspolitik. Um einen Beitrag zur notwendigen Konzeption diversitätssensibler Quartiersentwicklung in Form der Förderung nachbarschaftlicher Beziehungen zu leisten, wird das Thema Nachbarschaft in diversitätsgeprägten und armutsbelasteten Stadtteilen in vier Teilstudien untersucht. Dabei stehen die jeweiligen lokalen Variationen, wie Diskriminierungserfahrungen, digitale Nachbarschaftskontakte bauliche Probleme und lokale Konflikte um armutsgeprägte Zuwanderung im Fokus. Die Ergebnisse zeigen, dass Nachbarschaft eine Ressource für alltägliche Integrationserfahrung darstellt, welche durch kommunale Integrationspolitik adressiert werden kann. Vor allem die Förderung lokaler Angebotslandschaften und Digitalisierung ist dafür eine geeignete Strategie. Für die kommunalen Integrationszentren NRW bedeutet dies, dass sie raumbezogene Steuerungsinstrumente entwickeln sollten, welche sowohl die sozialstrukturellen Dynamiken als auch die lokalen Angebotsstrukturen im Blick behalten. Weiterhin bedarf es der dauerhaften Thematisierung von Rassismus und Diskriminierungserfahrung, wie die Ergebnisse nahelegen. Zudem ist es sinnvoll, auch raumbezogene Kooperationen zu entwickeln, um sozialräumlichen Herausforderungen zu begegnen sowie digitale Praktiken unter den Nachbarinnen und Nachbarn eines Stadtteils in den Blick zu nehmen. Die Kommunalen Integrationszentren NRW sind als mittlerweile etablierte und gut vernetzte kommunale Organisationseinheiten in der Lage, diese Steuerungsinstrumente zu entwickeln und zu implementieren.
Introduction: Many disease processes are accompanied and promoted
by increased inflammation in the body. Increased concentrations of high-sensitivity C-reactive protein (hs-CRP) in the blood are an indicator of subclinical inflammation, increased disease risk, and an increased risk of early death. A healthy plant-based diet and increased physical activity have been shown to reduce hs-CRP concentrations.
Objectives: Our objective was to test if a healthy lifestyle intervention program can improve hs-CRP levels and other risk factors.
Methodology: We are conducting a non-randomized, controlled intervention study with 6 times of measurement (baseline, after 2.5, 6, 12, 18 and 24 months). Participants in the intervention group (n = 104) took part in a 2.5-month intensive lifestyle program focusing on a plant-based diet (PBD), physical activity, stress management and group support. Currently they are in the less intensive phase (monthly seminars) which will be completed after 24 months. The control group (n = 62) did not take part in any program. In both groups hs-CRP was assessed, and participants with an infection/common cold at any of the times of measurement were excluded from the analyses.
Results: In the intervention group (n = 97) we observed a reduction in hsCRP from baseline to 2.5 months (p < 0.001). In the control group (n = 46) hs-CRP levels increased non-significantly. The changes from baseline to 2.5 months were significantly different between intervention and control (p < 0.01).
Conclusion: Our program led to a clinically relevant reduction in hs-CRP.
Continued follow-up will show if this improvement can be maintained in the intervention group. Our study confirms that a PBD and healthier lifestyle choices can lower hs-CRP.
Moderne IT-Organisation
(2021)
In der heutigen vernetzten Welt spielt die IT der Unternehmen eine entscheidende Rolle. In einer aktuellen Studie von KPMG wird die Forderung aufgestellt, dass die IT agiler, einfacher und schneller liefern muss (KPMG 2021). Eine der in diesem Zusammenhang fundamentalen Fragen aus Sicht der Unternehmen ist die nach der richtigen Organisation der IT zur optimalen Erfüllung aufgestellter Forderungen.
Die Corona-Rechnung
(2021)
Tactical planning measures for sustainable and efficient international transportation networks
(2021)
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.
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.
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.
The laser nitriding was performed in nitrogen gas at room temperature (20 °C) and low temperature (−190 °C) by a low power fiber laser to modify the wear and abrasion resistance of NiTi alloy. The surface roughness and element composition were analyzed by roughness device and energy-dispersive X-ray spectroscopy respectively. The results of roughness show that laser treatment can change the surface roughness due to the laser remelting. The effect of laser nitriding on the microhardness, friction coefficient, and worn scars of NiTi alloy was also studied, which shows that the microhardness of the NiTi alloy increases after laser nitriding. The optical microscope and scanning electron microscope were used to characterize the surface of NiTi alloy after wear testing to observe the microstructure of worn scars. The results show that the laser nitriding with different parameters can induce a nitride layer with different thicknesses and the higher energy deposition is the key factor for the formation of the nitride layer, which can decrease the friction coefficient and reduce wear loss during the application of NiTi alloy. The improvement of wear resistance can be attributed to the hard nitriding layer.
We experimentally study the occurrence of pattern formation during the slot-die coating of low-viscosity nearly Newtonian liquids onto Polyethylenterephthalat (PET)-substrates. In particular, it is demonstrated that with increase of the coating speed a homogeneous coating becomes unstable with respect to periodic stripe patterns. Thereby, depending on the liquid viscosity, the stripes can be oriented parallel or perpendicular with respect to the coating direction. Mixed states do also occur. The spatial period of perpendicular [parallel] stripes increases [decrease] with the coating speed. The dependence of the effect on various control parameters of slot-die coating is investigated. Finally, a simple theoretical model based on the hydrodynamics of thin films of partially wetting liquids is analysed. Comparing the results to the experiments, conclusions are drawn regarding the acting instability and pattern formation mechanisms.
Autismus-Spektrum-Störung
(2021)
Autismus-Spektrum-Störungen gehören zu den tiefgreifenden Entwicklungsstörungen. Sie sind charakterisiert durch Auffälligkeiten in der sozialen Kommunikation und Interaktion sowie das Vorhandensein von eingeschränkten und repetitiven Verhaltensweisen und Interessen. Prävalenzschätzungen gehen davon aus, dass bei ca. 1 % der Kinder und Jugendlichen eine Autismus-Spektrum-Störung vorliegt. Mittlerweile existiert eine Reihe an Förderprogrammen, die sich u. a. sowohl vom Altersspektrum (Frühintervention vs. Intervention im Kindes- und Jugendalter), der Intensität (hoch- vs. niedrigfrequentiert), der vermittelnden Gruppe (Therapeut, Eltern, Kindergarten und Schule) oder auch im Setting (Therapie-Setting vs. Lebensweltorientierung) unterscheiden. Aus dem Bereich der Frühintervention werden hier zwei Programme exemplarisch vorgestellt, wobei 1) MIA eine intensive und 2) A-FFIP eine niedrigfrequente Intervention darstellt. Zudem werden zwei Förderprogramme aus dem Kindes- bis jungen Erwachsenenalter besprochen. Sowohl 3) KOMPASS als auch 4) KONTAKT richten sich als Gruppenprogramm an Personen mit einem höheren kognitiven Funktionsniveau.
Digitalisierungsstrategie
(2021)
Coworking Spaces sind mittlerweile fester Bestandteil der digitalen Arbeitslandschaft in Großstädten. Nach und nach halten sie auch im ländlichen Raum Einzug. Studien und Modellprojekte haben bewiesen, dass sie sowohl gesellschaftlich als auch wirtschaftlich eine positive Wirkung auf strukturschwächere Regionen haben können. Sie bieten ein attraktives Umfeld für Kreative und Gründer und ermöglichen den Austausch mit lokalen Unternehmen. Außerdem können sie dafür sorgen, dass Pendler* innen zum Arbeiten vor Ort bleiben.
In weniger dicht besiedelten Regionen, wie dem Münsterland, ist der profitable Betrieb von Coworking Spaces bisweilen schwierig. Da naturgemäß die Standortwahl eines Coworking Space ein entscheidendes Kriterium für seine spätere Wirtschaftlichkeit ist, wird diese in der vorliegenden Studie untersucht. Dazu werden auf Coworking Spaces zugeschnittene und von Experten gewichtete Standortfaktoren aufgestellt und die 65 Orte des Münsterlands anhand dieser Faktoren bewertet. So entsteht ein Ranking, welches aufzeigt, wo die besten Voraussetzungen für Coworking Spaces herrschen.
In einigen Städten im Münsterland gibt es bereits Coworking Spaces. Einem Großteil dieser Orte wird durch diese Studie eine gute Eignung bestätigt. Beispielsweise schneiden Rheine und Bocholt aufgrund ihrer hohen Einwohnerzahl am besten ab. Es wird jedoch deutlich, dass auch andere Faktoren ausschlaggebend sein können. So bewerten Expert*innen die digitale Infrastruktur und Erreichbarkeit als sehr wichtig. Für diese Faktoren stellen vergleichsweise kleine Orte die Bestwerte, die bislang noch keine Coworking Spaces vorweisen können.
Die Ergebnisse informieren Betreiber*innen von Coworking Spaces und solche, die es werden wollen, sowie politische Entscheidungsträger*innen über mögliche Potenziale in den jeweiligen Orten. Sie zeigen auf, an welchen Stellschrauben gedreht werden kann, um gute Voraussetzungen zu schaffen. Darüber hinaus wird empfohlen, das entstehende Angebot aufeinander abzustimmen und gemeinschaftlich vorzugehen – so, wie es der Begriff Coworking bereits verdeutlicht.
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.
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.
In der Lebensgeschichte spielen bedeutsame Orte eine große Rolle, die auch in der Biografiearbeit zum Tragen kommt. Der Umgebungsradius älterer Menschen, die in Altenpflegeeinrichtungen leben, kann aufgrund gesundheitlicher und finanzieller Begrenzungen sehr eingeschränkt sein, Reisen können unter Umständen unmöglich sein. Aktuelle VR-Tech- nologie mit der Erfahrung der Immersion, des Eintauchens in die virtuelle Umgebung, könnte eine Möglichkeit sein, Orte (wieder) zu erleben, die schwierig oder unmöglich zu besuchen sind, und so in der Biografiearbeit genutzt werden. Die vorliegende Studie weist auf positive Effekte auf das Wohlbefinden hin und ermittelt Gratifikationseffekte der Nut- zung. Dabei sind besonders wichtige Kategorien Genuss, Hilfe beim Wiedererinnern und Erlebnis.
Gemeinkosten lassen sich oft nur schwer verursachungsgerecht über eine innerbetriebliche Leistungsverrechnung Kostenträgern zuordnen. Die zunehmende Digitalisierung schafft eine Datengrundlage, auf deren Basis eine Allokation der Kosten entsprechend ihrer tatsächlichen Inanspruchnahme erfolgen kann, indem Prozesse als Kostentreiber
genauer betrachtet werden.
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.
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.
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.
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.
Diese Arbeit befasst sich mit Kostentrends in Zusammenhang mit technologischem Lernen von Windenergie an Land in den USA, in Deutschland und weltweit. Ziel dieser Arbeit ist es, eine Lernkurve für Windenergie an Land zu bestimmen. Dafür wurden Daten zu Stromgestehungskosten (LCOE) und Kosten für die Installation (COP) von Windenergieanlagen (WEA) im Zeitraum von 1983 bis einschließlich 2020 gesammelt, grafisch dargestellt und weitergehend ausgewertet. Die grafische Darstellung der Datenlage verdeutlicht die zeitliche Entwicklung der Technologie. Zur Beschreibung dieser Lernkurven wurden die Progress Ratio (PR) und Learning Rate (LR) in fünf unterschiedlichen Modellen bestimmt. Anhand derer sich in Kombination mit der zukünftig installierten Leistung von WEA eine Prognose über zukünftige Kosten ableiten lässt. Die ermittelten LR bewegen sich zwischen 13 % und 28 %, woraus sich LCOE im Jahr 2030 zwischen 44,03 US$/MWh und 61 US$/MWh ergeben.
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.
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.
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.
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.
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.
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 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 EGU Journal of Renewable Energy Short Reviews (EGUJRenEnRev) is a teaching project rather that a regular scientific journal. To publish in this journal, it is a premise to take part in the master course wind power, hydro power and biomass usage at the faculty of Energy, Building Services and Environmental Engineering of the Münster University of Applied Sciences.
Students receive an equivalent of 2.5 credit points (European Credit Transfer and Accumulation System - ECTS) for their engagement in the course and for publishing a short review article of at most 3000 words in this periodical. The publication process closely mimics the typical publication procedure of a regular journal. The peer-review process, however, is conducted within the group of course-participants.
Although being just an exercise, we think that publishing the outcome of this course in a citable manner is not only promoting the motivation of our students, but may also be a helpful source of introductory information for researchers and practitioners in the field of renewable energies. We encourage students to write their articles in English, but this is not mandatory. The reader will thus find a few articles in German language. To further encourage students practicing English writing, perfect grammar is not part of the assessment.
We especially thank our students for working with LaTeX on Overleaf, although LaTeX is new to some of them. In this way, the editorial workload was reduced to a minimum. We also thank our students for sharing their work under the creative commons attribution licence (CC-BY). I appreciate their contribution to scientific information, being available to every person of the world, almost without barriers. I also thank the corresponding authors and publishers of the cited work, for granting permission to reuse graphics free of charge. All other figures had to be replaced or removed prior to publication.
Drei Jahre weniger Zwang
(2021)
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.
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.
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).
Zeit für eine Zwischenbilanz: Zehn Jahre Studiengang Psychische Gesundheit/Psychiatrische Pflege
(2021)
Im Forschungsprojekt „Digitales Dorfleben“ werden die Effekte digitaler Nachbarschaftsnetzwerke auf das Zusammenleben in ländlichen Räumen in Ost- und West-Deutschland untersucht. Die Mixed-Methods-Studie untersucht mit vier Untersuchungsdörfern (sog. Ankerfällen) und vier regionalen Vergleichsfällen insgesamt acht Dörfer. Zwei der Untersuchungsdörfer weisen eine hohe Nutzung von nebenan.de gemessen an der Bevölkerung auf, während sowohl die regionalen Vergleichsbeispiele als auch die übrigen Ankerbeispiele sich durch eine geringe Nutzung von nebenan.de auszeichnen. Bei nebenan.de handelt es sich um das größte deutschsprachigen digitale Nachbarschaftsnetzwerk. In den zu untersuchenden Dörfern werden sowohl qualitative Interviews als auch standardisierte Bevölkerungsbefragungen durchgeführt. Zudem werden sozio-ökonomische Kontextfaktoren der acht Fälle vergleichend untersucht. Das Projekt wird von der Kernfrage geleitet, inwiefern die Nutzung digitaler Nachbarschaftsplattformen einen Effekt auf das nachbarschaftliche Zusammenleben im ländlichen Raum hat und wie sich ein solcher Effekt gestaltet. Methodisch ist das Projekt Hypothesen-prüfend strukturiert und leistet einen Beitrag in der Erforschung von Digitalisierung in ländlichen Räumen. Für den Transfer werden in den vier Ankerfällen Dorfabende organisiert, bei denen die Projektergebnisse vorgestellt und mögliche Entwicklungspfade des Dorfes diskutiert werden. Das Projekt ist am interdisziplinären Institut für Gesellschaft und Digitales (GUD) der FH Münster angesiedelt und wird gefördert vom Bundesministerium für Landwirtschaft und Ernährung.
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.
Dieses Lehrbuch führt in die Grundlagen der Immobilienbewertung ein. Studierende lernen sowohl die normierten Verfahren nach Immobilienwertermittlungsverordnung (ImmoWertV) als auch zwei sog. nicht normierte Verfahren zur Wertermittlung kennen. 23 Kurzvideos zum Vorgehen bei den einzelnen Methoden der Wertermittlung und Beispielrechnungen veranschaulichen den Lehrstoff und unterstützen beim Lernen. Das Lehrbuch ist in der Springer Vieweg Reihe "erfolgreich studieren" erschienen.
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.