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    Research data management in agricultural sciences in Germany: We are not yet where we want to be
    (San Francisco, California, US : PLOS, 2022) Senft, Matthias; Stahl, Ulrike; Svoboda, Nikolai
    To meet the future challenges and foster integrated and holistic research approaches in agricultural sciences, new and sustainable methods in research data management (RDM) are needed. The involvement of scientific users is a critical success factor for their development. We conducted an online survey in 2020 among different user groups in agricultural sciences about their RDM practices and needs. In total, the questionnaire contained 52 questions on information about produced and (re-)used data, data quality aspects, information about the use of standards, publication practices and legal aspects of agricultural research data, the current situation in RDM in regards to awareness, consulting and curricula as well as needs of the agricultural community in respect to future developments. We received 196 (partially) completed questionnaires from data providers, data users, infrastructure and information service providers. In addition to the diversity in the research data landscape of agricultural sciences in Germany, the study reveals challenges, deficits and uncertainties in handling research data in agricultural sciences standing in the way of access and efficient reuse of valuable research data. However, the study also suggests and discusses potential solutions to enhance data publications, facilitate and secure data re-use, ensure data quality and develop services (i.e. training, support and bundling services). Therefore, our research article provides the basis for the development of common RDM, future infrastructures and services needed to foster the cultural change in handling research data across agricultural sciences in Germany and beyond.
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    Modelling the final discharge angle in flighted rotary drums
    (Berlin ; Heidelberg : Springer, 2022) Seidenbecher, J.; Herz, F.; Sunkara, K.R.; Mellmann, J.
    Rotary drums equipped with longitudinal flights are mainly used to dry granular solids and handle high throughputs. The design of the flights is a crucial task because they decisively influence the distribution of the particles over the dryer cross section. In a previous work, the authors derived a mathematical model for the particle flow in rotary drums with rectangular flights. In this model, the final discharge angle was underpredicted resulting in errors when calculating the contact area of the particles in the air-borne phase. Therefore, a new model was developed in this study to predict the final discharge angle based on a forces balance approach on a single particle. This approach includes the Coriolis force acting on the last discharging particles sliding down the inclined flight sheet. The model was solved by using the vector analysis method. Experiments were performed at rotary drums with 0.5 m and 1.0 m in diameter, respectively, and 0.15/0.3 m in length using glass beads and quartz sand as bed materials. Each drum was equipped with 12 flights around the shell. The model validation was performed by varying the bed material, drum diameter, flight length ratio, and the rotating speed. The model predictions have shown that as the flight length ratio and the Froude number increased, the final discharge angle attained higher values. The model predictions agree well with the measurements. Graphic abstract: [Figure not available: see fulltext.].
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    Solar energy policy implementation in Ghana: A LEAP model analysis
    ([Amsterdam] : Elsevier B.V., 2022) Amo-Aidoo, A.; Kumi, E.N.; Hensel, O.; Korese, J.K.; Sturm, B.
    Current global climate change mitigation programs have been unable to meet the Paris Agreement's targets, and Ghana's situation is no exception. There is, therefore, an increased need for intensification of renewable energy deployment programs with an emphasis on solar energy as it constitutes about 90% of Ghana's installed renewable energy generation capacity. The study demonstrates how appropriate renewable energy policy can drive solar energy development in Ghana. Electricity demand scenarios were developed using historical data from 2000 to 2018, after which projections were made up to 2030 based on the average year-on-year electricity growth rate. Of the three electricity demand categories, residential demand experienced a steeper growth rate in comparison with the special load tariff, non-residential, and street lighting sectors. On the supply side, low, moderate, and visionary supply scenarios had increased solar penetration of 5 %, 10 %, and 15 % of the installed generation capacity respectively. While appreciable gains were made in the low and moderate supply scenarios, the visionary supply scenario could meet the renewable energy target with solar energy by 2030; leading to universal access to electricity while offsetting over 13 million metric tonnes of carbon dioxide in the process.