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RFID tags will really become smart objects of the Internet of Things (IoT) if they will be able to exploit the passive nature of the communication also for exchanging data with any other networked devices in the Internet. To this aim, an adaptation layer, named 6lo-RFID, has been specifically designed to run IPv6 over the RFID link technology. In this paper we draw the design principles for the development of a fully passive, IPv6-compliant, and energy-efficient 6lo-RFID tag platform. In particular, we discuss the block's design of an RF energy harvester and evaluate the simulated performance of a fully-passive 6lo-RFID tag when GET/PUT CoAP methods are used to execute operations on the tag memory.

Metadata only record Within the last thirty years in the West African Sahel, farmers have started to implement agroenvironmental practices which have allowed them to improve the soil quality and increase crop yields. Using two examples of land rehabilitation in Africa, this paper examines the technical and institutional innovations and their impacts on the ability to meet food demand for the growing population. Agroenvironmental techniques incorporate trees into the agricultural landscape, which improves water retention in the soil, increases the supply of nutrients, reduces wind erosion, and provides other marketable tree products. This large-scale effort has created income opportunities for farmers, benefited women, and increased food supply for many African families.

Das Passivhaus Institut hat eine große Anzahl genutzter Passivhäuser in Europa messtechnisch ausgewertet und konnte nachweisen, dass der Heizwärmebedarf neu gebauter Passivhäuser im Bereich von 15 kWh/m2a liegt, was nur 10-20% des Heizwärmebedarfs des Green Building oder anderer Energiesparstandards für Gebäude in China entspricht. Mit dem Passivhaus können den Heizwärmebedarf und die CO2-Emissionen in China erheblich gesenkt werden, was für die chinesische Regierung und Gesellschaft von großer Bedeutung ist. Folglich hat China im Zeitraum 2016-2020 mehr als 10 Millionen Quadratmeter Niedrigstenergiegebäude (Passivhäuser) gebaut und wird bis 2025 weitere 50 Millionen Quadratmeter errichten. Daher ist die Hauptmotivation dieser Arbeit, den Energieverbrauch von Passivhäusern in China zu untersuchen. Ziel ist, die Anwendbarkeit der Passivhausstandards unter Berücksichtigung der chinesischen Nutzergewohnheiten und klimatischen Besonderheiten zu validieren und ergänzende Vorschläge für die Anwendung zu unterbreiten. Für diese Arbeit wurden ein Passivhaus-Wohngebäude, ein Passivhaus-Bürogebäude und ein Green Building im Deutsch-Chinesischen Ökopark Qingdao, Nordchina, als Gegenstand der Untersuchung ausgewählt. Die angewandte Forschungsmethode gliedert sich im Wesentlichen in vier Schritte: a) Einrichtung eines Energieverbrauchsüberwachungssystems, um Energieverbrauchsdaten zu erhalten. b) Passivhaus-Planungspaket (PHPP), Therm und IBE sind Simulationswerkzeuge, die in dieser Arbeit zur Bewertung des Gebäudeenergieverbrauchs und der Wärmebrücken verwendet werden. c) Vergleich der Energieverbrauchsdaten des Passivhausgebäudes mit den simulierten oder entworfenen Energieverbrauchsdaten und schließlich d) Ermittlung der Unterschiede zwischen den beiden Datensätzen durch Analyse der Ursachen, um die Energieeffizienz des Gebäudes zu optimieren und aufzuwerten. Für die Studie wurden zunächst 3-jährige Betriebsdaten des 2016 errichteten Passivhauses-Bürogebäude ausgewertet. Das Gebäudesystem wurde gemäß den Daten des hohen Energieverbrauchs im Jahr 2017 in Betrieb genommen. Danach waren die Energieverbrauchsdaten in den folgenden zwei Jahren deutlich niedriger. Dies zeigt, wie wichtig die Inbetriebnahme der HVAC-Anlage für große öffentliche Passivhausgebäude ist. Die Analyse der Energieverbrauchsdaten und der innere Komfort-Parameter für die folgenden zwei Jahre ergab, dass der Heizwärmebedarf größer war als der simulierte Wert und der Kühlbedarf gut mit dem simulierten Wert übereinstimmte. Der innere Komfort des Gebäudes wurde das ganze Jahr über innerhalb des festgelegten Komfortbereichs gehalten. Zweitens wurde ein Passivhaus-Wohngebäude mit 36 Wohneinheiten, das im Jahr 2020 fertiggestellt wurde, messtechnisch begleitet. Erstmalig wurde ein Passivhaus-Wohngebäude in China messtechnisch ausgewertet. Während des Überwachungszeitraums ergab ein umfassender Vergleich der Entwurfs- und Konstruktionstechniken zwischen dem Passivhaus-Wohngebäude und einem benachbarten als Green Building gebauten Wohngebäude, dass im Passivhaus-Wohngebäude der Heizwärmebedarf im Vergleich zu dem Green Building Wohngebäude erheblich reduziert wurde, und es wurde vorgeschlagen, dass eine groß angelegte Förderung von Passivhäusern ein vorteilhafter Weg wäre, um Chinas Dual-Carbon-Ziele zu erreichen. Nach Abschluss der Überwachung zeigte die Analyse, dass der tatsächliche Heizwärmebedarf höher war als der vorhergesagte Wert, und dass der Primärenergieverbrauch und der innere Komfort den Passivhausstandards entsprachen. Die Gründe für den höheren Heizwärmebedarf sind 1) die Belegungsrate von nur 47% (17/36) im ersten Bezugsjahr und 2) Baufeuchte und Nutzerverhalten. Die Anwendbarkeit des Passivhausstandards in der kalten Klimazone und in der Küstenregion Nordchinas wurde an den beiden ausgewählten Passivhausgebäuden nachgewiesen. Die beobachteten Ergebnisse entsprechen im Wesentlichen den Passivhausstandards. Aufgrund des Nutzerverhaltens und der Belegungsrate entspricht ein Teil der Indikatoren nicht den Erwartungen, jedoch zeigt das Passivhausgebäude herausragende Vorteile in Bezug auf Energieeinsparung und Innenraumkomfort, verglichen mit den aktuellen Green Building oder anderen Gebäudeenergieeinsparungsstandards in China. German Passive House Institute has monitored many operating passive houses in Europe to prove that the heating demand of newly built passive houses is in the range of 15 kWh/m2a, which is only 10-20% of the heating demand of Green Building Standards or other building energy-saving standards in China. The passive house can significantly decrease heating demand and reduce CO2 emissions in China, these issues are of great concern to the Chinese government and society. Consequently, China built more than 10 million square meters of ultra-low energy buildings (passive houses) in 2016-2020 and will build another 50 million square meters by 2025. Hence, to do monitoring research on the energy consumption of passive houses in China is the main motivation of this thesis. The goal is to validate and supplement the applicability of the Passive House Standards considering the Chinese user habits and local climate characteristics. One passive house residential building, one passive house office building and one Green Building in Sino-German Ecopark Qingdao in northern China are selected for this thesis. The research method used is mainly divided into four steps: a) establishing an energy consumption monitoring system to obtain energy consumption data. b) Passive House Planning Package (PHPP), Therm, and IBE are simulation tools used in this thesis to evaluate building energy consumption and thermal bridges. c) comparing the energy consumption data of the passive house building in operation with the simulated or designed energy consumption data, and then d) finding out the differences between the two sets of data, through analyzing the reasons to achieve the purpose of improving and upgrading the energy efficiency of the building. Firstly, 3 years of operational data of the passive house public building built in 2016 were analyzed. The building system was commissioned through the data of high energy consumption in 2017. Then, the energy consumption data for the subsequent 2 years were significantly lower. It showed the importance of HVAC commissioning for large passive house public buildings. The analysis of the energy consumption data and indoor environment parameters for the subsequent 2 years revealed that the space heating demand was larger than the simulated value and the cooling demand matched the simulated value well. The building’s indoor environment was maintained within the set comfort range year-round. Secondly, a passive house residential building containing 36 apartments, which was completed in 2020, was selected for monitoring. This is the first time that a passive house residential building was monitored in China. During the monitoring period, a comprehensive comparison of the design and construction techniques between the passive house residential building and a neighbouring Green Building residential building revealed that the passive house residential building would significantly reduce space heating demand, and it was suggested that large-scale promotion of passive houses would be a beneficial way to achieve China's dual carbon goals. After the monitoring was completed, the analysis showed that the actual heating demand was higher than the predicted heating demand, and the primary energy consumption and indoor comfort met the passive house standards well. The reasons for the higher heating demand are 1) the occupancy rate of only 47% (17/36) in the first moving-in year and 2) initial wall moisture and user behavior. The applicability of Passive House standards in the cold climate zone and coastal region of northern China was proven in the selected two passive house buildings. The monitored results meet basically the passive house standards. Because of the user behavior and occupation rate, part of the indicators doesn’t meet expectations, however, the passive house building shows outstanding advantages in terms of energy-saving and indoor comfort, compared with other current Green Building Standards or other building energy-saving standards in China.

Purpose: Sustainability is one of the major key terms in our modern globalized world affected by such different but nevertheless closely interrelated issues like prosperity of worldwide trade, globally-spanning supply chains, the growing social gap and the threatening effects of climate change. The paper shows how responsible citizenship and reflective critical thinking as well as a deeper understanding of these complex interdependencies can be conveyed in a systematic way to a group of international business students in form of a one-week block seminar course in the CEMS Master-in-International-Management (MIM) program.Design/methodology/approach: The paper includes a discussion of proven course design, general key skills fostered, didactic approaches and methods employed along with feedback mechanisms and evaluation results demonstrating clearly its impact on student’s mind sets afterwards.Findings: Based on the discussions with our students and post-course reflective reports it turned out, that for many of them their perception of sustainability issues and of their own behaviour has changed during this single week because of the topics dealt with in our course.Practical implications: A well thought-out didactic approach and extraordinary commitment and dedication by the instructors is inevitable to ensure the success of such a course.Original/value: This paper explains in a compact way, how sustainability issues in global supply chain management can be tackled successfully even in such time restricted one-week block seminar. Purpose: Sustainability is one of the major key terms in our modern globalized world affected by such different but nevertheless closely interrelated issues like prosperity of worldwide trade, globally-spanning supply chains, the growing social gap and the threatening effects of climate change. The paper shows how responsible citizenship and reflective critical thinking as well as a deeper understanding of these complex interdependencies can be conveyed in a systematic way to a group of international business students in form of a one-week block seminar course in the CEMS Master-in-International-Management (MIM) program.Design/methodology/approach: The paper includes a discussion of proven course design, general key skills fostered, didactic approaches and methods employed along with feedback mechanisms and evaluation results demonstrating clearly its impact on student’s mind sets afterwards.Findings:Based on the discussions with our students and post-course reflective reports it turned out, that for many of them their perception of sustainability issues and of their own behaviour has changed during this single week because of the topics dealt with in our course.Practical implications: A well thought-out didactic approach and extraordinary commitment and dedication by the instructors is inevitable to ensure the success of such a course.Original/value: This paper explains in a compact way, how sustainability issues in global supply chain management can be tackled successfully even in such time restricted one-week block seminar.

The road network design problem is widely studied in the literature, both in urban and rural areas; most papers deal with the solution algorithms and with the mathematical formulation of the problem. The road network design problem is NP-hard and is very difficult to solve in acceptable computing times for real-scale networks. In urban areas, the objective of the design is usually the minimisation in total travel time on the network, while in rural areas it is usually a sum of total travel time and total (i.e. construction and maintenance) road costs. Very few papers consider other terms in the objective function and/or propose a multicriteria approach. In our best knowledge, no papers consider as objective of the design to minimise the fuel consumption, even if it is an actual objective of road network planning and design. In this paper, we compare the results obtained by solving some road network design problems adopting the classic objective functions and adopting as objective the minimisation in fuel consumptions on the network. In order to obtain this result, in the paper a fuel consumption function is proposed, based on CORINAIR models and depending on the vehicle fleet of the study area; this function is used both for estimating the reduction in fuel consumption due to the design obtained with the classic objective functions and for designing the road network using as objective function the total consumption on the network. The results obtained with these approaches are compared in terms of fuel consumed and total travel time spent on the network. The minimisation in fuel consumption is very important since greenhouse gas emissions and air pollutants are directly related to the consumption. Initial tests highlighted that the results obtained with the two different approaches are more significant in rural areas, where higher average flow speeds may produce higher consumption, according to the CORINAIR models.

The EPBD, together with other acts and funding programs, strongly promotes the passive strategies in order to achieve, above all in summer, indoor comfort conditions, reducing or avoiding the active air-conditioning. The adoption and the design of these strategies are not indifferent to the specific boundary conditions. In this paper, the performances achievable adopting an earth-to-air heat exchanger for an air-conditioned building are evaluated for winter and summer. The analysis has been carried out on varying the main boundary conditions related to the environmental context, the soil, the tube properties and connected behaviours of the airflow crossing it. Several control strategies have been simulated too, in order to propose the most suitable design criteria for each climate. The fan electrical energy represents a design critical aspect, requiring an accurate evaluation, in order to achieve the maximum thermal exchange and limiting the pressure drops inside the buried pipes. Otherwise, the use of an EAHX can be also penalizing.

The demand for effective cooling and energy storage technologies is growing continuously. The climatic changes, miniaturization, and digitalization have redefined the technological development in the cooling and energy storage industries. The global focus is on the environmental-friendly, efficient, sustainable, and scalable cooling technologies. Owing to all these factors, green alternatives to the traditional air-conditioning and refrigeration are gaining momentum. One of such green alternatives is the electrocaloric effect (ECE). The electrocaloric effect is observed in dielectric materials as they undergo an adiabatic temperature change or an isothermal entropy change under an externally applied/removed electric field. Dielectric materials are capable to store the electrical energy as well. Therefore, they are particularly interesting for the new cooling and energy storage technologies. In this work, a ferroelectric relaxor polymer, namely, Poly(vinylidene fluoride – trifluoroethylene – chlorofluoroethylene) (P(VDF–TrFE–CFE) is investigated for the electrocaloric effect through the direct and the indirect methods. The electrical energy storage properties of different compositions of P(VDF–TrFE–CFE) and their nanocomposites with inorganic 0D nanofillers are studied. Initially, the relaxor properties in six different compositions of P(VDF–TrFE–CFE) are studied. Out of these six compositions, the three compositions, 51.3/48.7/6.2, 59.8/40.2/7.3, and 70/30/8.1, are analyzed for the first time. The field induced phase transition results in a double hysteresis loop in a few compositions. Through the direct electrocaloric measurements, it is observed that the electric field induced phase transition results in a higher electrocaloric temperature change. The indirect electrocaloric measurements are conducted with and without compensating the leakage current. It is shown that the indirect method can lead to erroneous results due to the leakage current. The results obtained through the indirect measurements conducted with the leakage current compensation are comparable to the direct measurements. The electrical energy storage properties of the neat terpolymers and their nanocomposites are compared. It is observed that the stored and discharged energy densities of the nanocomposites are superior to the neat terpolymers. Dissertation, Universität Duisburg-Essen, 2022

Conflict framing-the emphasis on clashing political positions, or the reproach of one actor to another-is central in political coverage and politics. This chapter discusses its conceptualization and the subsequent consequences for citizens' political attitudes and behavior. Previous research on conflict framing has yielded mixed results, showcasing conflicts' potential to inform and engage citizens alongside fostering cynicism and polarization. In this chapter, we argue that, to understand these divergent findings, it is necessary to distinguish between different types of conflicts. To address the fragmented literature on conflict and negativity, we propose a typology of various conflict types. This typology is exemplified through a hypothetical conflict scenario centered around climate change. We evaluate the moral, political, and epistemic implications of distinct conflict frames and propose conditions under which conflicts can positively contribute to deliberative democracy. Our typology provides a starting point for further investigations into the effects of conflict frames.