Assessing the effect of a white Portland cement admixture on the early frost-thaw resistance of NHL-based masonry mortar

Well preserved mortars based on natural hydraulic lime are widely spread in historical buildings throughout the alpine area of Tyrol, Austria. These are frequently restored with mortars oriented on historical models. Portland cement is also commonly used to modify these materials on building sites to speed up the setting time to improve the early frost-thaw resistance, primarily when they are applied around the winter season. Therefore, it was our objective to specify the application potentials of those materials, respecting the intended use and the atmospheric conditions. Moreover, we tried to figure out the possible benefits and risks when using NHL-based materials, optionally modified by cement, yielding stable recommendations for the work with corresponding mortars. Hence, we examined the development of strength and water transport, also the frost-thaw durability in a temporal context. The obtained results were compared with findings of assessing both materials under variable weather conditions around the winter season. Accordingly, the use of pure NHL-based lime mortars resulted as being critical mainly until about two months before intense frost conditions. Cement effectively contributes to the rapid hydraulic setting reaction in NHL-based materials. Hence, we recommend measured cement additions in areas where strong frost is expected after a few weeks and especially targeted in areas where carbonation is hindered because of excess moisture. Nevertheless, the potential use of Portland cement should be properly controlled in historic building preservation. A systematical approach that considers the framework conditions and the corresponding application to an area is essential to assure an appropriate conservation outcome.

On the Road to Circular Public Procurement: Case, Variations, and Potential Actions in Germany

According to the United Nations, the consumption of materials is expected to double between 2020 and 2050. At the same time, annual waste generation is forecast to increase by 70% by 2050. The circular economy (CE) addresses this problem. However, many barriers to the further development of the CE exist. This article analyses the situation of public procurement in supporting a sustainable CE for tyres in Germany based on 18 interviews with public procurement professionals directly responsible for the purchase of tyres and four additional expert interviews. Based on the dimensions ‘current circular public procurement (CPP) intensity’ and ‘current CPP opportunities’, a classification of tyre procurement situations and barriers to sustainable circular tyre procurement is presented. Strategies to overcome these supply-side and demand-side barriers are specified, resulting in nine recommendations for German policymakers. As a way forward, a detailed concept for a pilot project on tyre CPP is provided. The article also shows how the circular public procurement classification can be used to support sustainability measures in a broader context. Finally, the article’s outlook focuses on implications to promote sustainable circular tyre procurement in other countries. It explains different framework conditions and elaborates to what extent additional research is necessary to develop appropriate recommendations for those conditions.

Costs and optimisation options for monitoring of indirect dischargers

Monitoring of indirect and industrial dischargers, respectively, makes an important contribution to the safe and environmentally sound operation of wastewater systems. As a result of local framework conditions, there is a wide range of monitoring practices across Germany. In a benchmarking project, ten sewerage operators and monitoring bodies representing large German cities have collected data on their work and discussed their practices. The results show that the extent of monitoring is between 244 and 1,457 monitoring points per sewer network (given as 15th and 85th percentile). The median value of the specific expense is 689 EUR per monitoring point and year. In relation to the total wastewater fee volume, the median expense is 0.71%. The sub-process ‘sampling’ was examined more closely. By means of detailed process mapping and regression analyses, it can be shown that on-site activities and tours have the largest share of working time (total of 72%) and thus the greatest leverage in optimisation measures. Various examples are given.

The role of culture in policy transfer. A pilot study for transferring European models of peer review in vocational schools to China

To achieve a successful policy transfer from one country to another, knowledge is required about the framework conditions of the country to which the policy is transferred. An important framework condition to consider is cultural context. Therefore, this paper uses a combination of cultural definitions which consider culture as a driver for both the interpretation of its members and for the communicative and interactive behaviour within a community. This contribution presents a cultural concept to inform policy transfer from a European context to China. Chinese philosophical approaches such as Taoism, Confucianism and Buddhism, as well as the political history of China, are used to identify individual perspectives within a community that depends, among others. A pilot study for testing the peer review process in vocational education and training will also help build a better understanding of how adjustments, transfer errors and side effects can be culturally explained.

Influence of Efficiency, Aging and Charging Strategy on the Economic Viability and Dimensioning of Photovoltaic Home Storage Systems

PV in combination with Li-ion storage systems can make a major contribution to the energy transition. However, large-scale application will only take place when the systems are economically viable. The profitability of such a system is not only influenced by the investment costs and economic framework conditions, but also by the technical parameters of the storage systems. The paper presents a methodology for the simulation and sizing of PV home storage systems that takes into account the efficiency of the storage systems (AC, DC standby consumption and peripheral consumption, battery efficiency and inverter efficiency), the aging of the components (cyclic and calendar battery aging and PV degradation), and the intelligence of the charging strategy. The developed methodology can be applied to all regions. In this paper, a sensitivity analysis of the influence of the mentioned technical parameters on the dimensioning and profitability of a PV home storage is performed. The calculation is done for Germany. Especially, battery aging, battery inverter efficiency and a charging strategy to avoid calendar aging have a decisive influence. While optimization of most other technical parameters only leads to a cost reduction of 1–3%, more efficient inverters can save up to 5%. Even higher cost reductions (more than 20%) can only be achieved using batteries that age less, especially batteries that are less sensitive to calendar aging. In individual cases, a small improvement in the efficiency of the storage system can also lead to higher costs. This is for example the case when smaller batteries are combined with a large PV system and the battery is used more due to the higher efficiency. This results in faster ageing and thus earlier replacement of the battery. In addition, the paper includes a detailed literature overview on PV home storage system sizing and simulation.

Current experimental developments in 48 V-based CI-driven SUVs in response to expected future EU7 legislation

In this paper, we describe experimental developments in an Exhaust Aftertreatment System (EAS) used in a four-cylinder Compression Ignition (CI) engine. To meet the carbon dioxide (CO$$_\mathrm {2}$$ 2 ) fleet limit values and to demonstrate a clean emission concept, the CI engine needs to be further developed in a hybridized, modern form before it can be included in the future fleet. In this work, the existing EAS was replaced by an Electrically Heated Catalyst (EHC) and a Selective Catalytic Reduction (SCR) double-dosing system. We focused specifically on calibrating the heating modes in tandem with the electric exhaust heating, which enabled us to develop an ultra-fast light-off concept. The paper first outlines the development steps, which were subsequently validated using the Worldwide harmonized Light-duty vehicles Test Cycle (WLTC). Then, based on the defined calibration, a sensitivity analysis was conducted by performing various dynamic driving cycles. In particular, we identified emission species that may be limited in the future, such as laughing gas (N$$_\mathrm {2}$$ 2 O), ammonia (NH$$_\mathrm {3}$$ 3 ), or formaldehyde (HCHO), and examined the effects of a general, additional decrease in the limit values, which may occur in the near future. This advanced emission concept can be applied when considering overall internal engine and external exhaust system measures. In our study, we demonstrate impressively low tailpipe (TP) emissions, but also clarify the system limits and the necessary framework conditions that ensure the applicability of this drivetrain concept in this sector.

Specific cultural and political challenges in cross-border public participation

The Site Selection Act (StandAG) regulates the individual procedural steps for a scientifically sound, participatory and transparent search and selection of a site for the safe final disposal of high-level radioactive waste. The result should be supported by a broad social consensus; those affected should be able to tolerate the outcome. For Germany, as the European country with the most neighbouring states, it is likely that some of the sub-areas, siting regions and possible sites defined in the selection procedure will be located on or in the immediate vicinity of one or more national borders; however, in the construction of a repository for high-level radioactive waste, “affectedness” does not stop at national borders, so that the public (citizens and other stakeholders) from neighbouring countries must be involved in the participation processes at an early stage and on an ongoing basis. The focus of this presentation lies on the challenges of cross-border participation based on previous experience in other subject areas and specific cultural and political framework conditions in neighbouring countries. We therefore address the following questions: What risks and obstacles must be taken into account in cross-border public participation and how can these be overcome? What specific cultural and political framework conditions exist in neighbouring countries and to what extent can these have an effect? The literature on cross-border cooperation describes that regions that cooperate across borders face particular challenges because they are each integrated into different national, institutional and legal systems in which responsibilities and competences may be assigned differently (cf. Beck, 2018; Scherer and Zumbusch, 2011; UNECE, 2009). Identifying and implementing success factors is a major challenge and can at the same time be an important prerequisite for successful transboundary participation in the search for a repository. Indications in this respect can be derived from other cross-border procedures between Germany and neighbouring states (cf. Abromeit, 2007; Nijsten and Paulussen, 2004; Saxenhofer et al., 2017). Participation and its manifestation within a state, a region or a specific place is strongly dependent on the respective cultural and political framework conditions. Nation states have different characteristics in their political systems as well as political cultures (Rogoff, 2015; Enserink et al., 2007). In Western Europe they differ primarily in terms of their democratic model, i.e. whether, for example, they are more parliamentary-representative or direct-democratic and whether there are more centralised or decentralised responsibilities and decision-making powers. The political culture is primarily determined by the way state and non-state actors interact and cooperate with each other, which is also reflected in the way public participation in decision-making is handled. Historical factors play an important role here. In certain thematic fields or issues, there can be a long tradition of cooperative processing and solving of problems. The research project HErüber (Sperfeld et al., 2021), which is commissioned by the Federal Office for the Safety of Nuclear Waste Management (BASE), analyses specific risks and obstacles, as well as cultural and political framework conditions. Based on a literature review, first results are presented.

Towards a Common Agricultural Data Space in the European Union: A Sustainable Development Perspective

In February 2020 the European Commission announced a new strategy for data in which an innovative proposal to create a single European data space composed of many sectoral common data spaces, including the agriculture sector, was presented. It is expected that the common agricultural data space will provide support for delivering a smart, innovative and sustainable agri-food system from farm to fork. Based on the analysis of framework conditions for pooling and sharing agricultural data in the EU and the Commission’s initiatives in this area, this article aims to discuss how and to what extent the common data space in agriculture could contribute to environmental, economic and social sustainability in the EU. It was concluded that the achievement of sustainability goals with the help of the planned common data space remains challenging, particularly in the context of rapid, but uneven pace of digital transformation in the agri-food sector in the EU. Overcoming legal, technical and other barriers to data sharing in the EU will not remove the fundamental problems of limited representativeness of current agricultural data assets in the EU. The design of the common data space in agriculture as well as the rules for data access and use should therefore be carefully considered. Also, specific and datarelated intervention measures, e.g. under the CAP, would be needed both to decrease the problem of a fragmented farm data landscape and to respond to the growing needs to collect and share private farm data that are highly relevant to achieving broader social goals and sustainability.

Sustainable development and the role of business

Sustainable development has various aspects - managerial, economic, environmental, social. It is an aspiration for politics and way of life of the population and above all - the state of the economy. The concept of sustainable development envisages economic growth that is able to meet the needs of modern society in the long run. The wheel of progress revolves only in conditions of economic freedom, respect for private property and equality before the law, which are provided by the institutional framework. People with hearts and minds - the combination of human imagination and the will to succeed - is the critical resource that provides sustainability. It works most effectively in the face of unlimited exchange of goods and services, access to knowledge and sharing of ideas, and the Internet already removes all the physical barriers to its power. All this happens not despite, but thanks to population growth, consumption of resources and wealth that maintain a closed cycle of pressure and response. Future generations will also need to keep the wheel of progress moving, so the best we can do is to preserve the framework conditions and give them the knowledge and the will.

Never Too Late to Learn: How Education Helps Female Entrepreneurs at Overcoming Barriers in the Digital Economy

The study of Entrepreneurship Framework Conditions (EFC) has found that training and education have, among other things, a positive effect on overcoming barriers when starting your own firm. Our research can be placed in this line, but with an added specificity, since it is focused firstly on women and secondly on the digital economy. Thus, we have studied the situation of women entrepreneurs in the digital economy in Spain, asking them about their personal traits, the characteristics of their ventures and the barriers they encountered. We have studied the effect of EFCs on overcoming barriers to entrepreneurship, with a special focus on training and entrepreneurship education. In addition, the effect of self-efficacy perception (the conviction of having the necessary skills to start a business) on overcoming barriers to entrepreneurship has been factored in. After the implementation of a Structural Equation Model (SEM), we show that training helps female entrepreneurs in the digital economy to overcome barriers to entrepreneurship, especially after the mediation of their self-efficacy perception, which is increased by specific entrepreneurial training. We can conclude that policy recommendations to counteract the gender gap in entrepreneurship with specific training should be promoted, specifically in such a strategic sector as the digital economy.