36 research outputs found
Impact of Global Climate Change on the European Barley Market Requires Novel Multi-Method Approaches to Preserve Crop Quality and Authenticity
Most recently in 2018 and 2019, large parts of Europe were affected by periods of massive drought. Resulting losses in cereal yield pose a major risk to the global supply of barley, as more than 60% of global production is based in Europe. Despite the arising price fluctuations on the cereal market, authenticity of the crop must be ensured, which includes correct declaration of harvest years. Here, we show a novel approach that allows such differentiation for spring barley samples, which takes advantage of the chemical changes caused by the extreme drought. Samples from 2018 were successfully differentiated from those of 2017 by analysis of changes in near-infrared spectra, enrichment in the isotope (13)C, and strong accumulation of the plant-physiological marker betaine. We demonstrate that through consideration of multiple modern analysis techniques, not only can fraudulent labelling be prevented, but indispensable knowledge on the drought tolerance of crops can be obtained
Design and Performance of a Conduction-Cooled HTS Magnet in the Radio-Blackout Experiment COMBIT
In the framework of the Helmholtz-Russia Joint Research Group (HRJRG) „COMBIT“ we developed a conduction-cooled HTS magnet to provide a high magnetic field for a radio blackout mitigation experiment in the arc-heated wind tunnel L2K at the German Aerospace Center in Cologne. The radio blackout phenomenon is well-known since the early days of space exploration. During hyper-sonic flights or during reentry in a planet\u27s atmosphere a dense plasma layer can form at the surface of the space vehicle leading to mitigation or reflection of radio waves. As a consequence voice communication with ground stations and GPS data telemetry can be disturbed. The goal of “COMBIT” was to demonstrate that the radio blackout can be mitigated by a local reduction of the plasma density in the vicinity of senders and antennas by magneto-hydrodynamic effects using crossed electric and magnetic fields. In order to generate a high magnetic field in the plasma we developed a conduction-cooled HTS magnet and a cryogenic system that is able to withstand the high temperatures in the plasma. The HTS magnet was made with RE-Ba-Cu-O coated conductors and has an outer diameter of only 70 mm. Despite the small size which is a consequence of the experimental boundary conditions the magnet was able to generate a high and variable magnetic field outside the cryostat in the plasma. In several measurement campaigns, the magnetic field reached up to 2 T in the plasma, corresponding to a maximum magnetic field of 5.16 T at the conductor. Mitigation of the radio blackout could be demonstrated successfully. After an introduction to the radio blackout phenomenon we present the design of the conduction-cooled HTS magnet and the cryogenic system and discuss their performance during the experimental campaigns
Methodisches System zur Auslegung von kostenoptimalen und prozessstabilen Fertigungsverkettungen
Intention of this task has been to verify that an optimal definition of manufacturing tolerances along the process chain can be achieved by a selective precocious, cost-optimal and stable manufacturing planning. This was carried out by a development of a framework system for the cost-optimal and stable design of manufacturing chains without prior definition of manufacturing tolerances along the process chain. The system starts with the assignment of design specifications with concrete manufacturing processes. A new model was developed, weighting the selected manufacturing processes on basis of their influence on product functionality, work piece characteristics and product purposes. Based on the methods of Fallböhmer and Trommer a manufacturing chain was generated using the selected manufacturing processes. In the following system modules, this manufacturing chain was used as basis for the creation of process alternatives. The process alternatives insist of the same manufacturing processes, which however differ in their parameters and actuating variables. Since the variation of the actuating variables within the allowed spread results in a huge quantity of process alternatives, initially a new model for the alternative reduction was developed. This model is based on the methodology for design of experiments and reduces the existing testing plans. By means of the testing plans, the influences of the manufacturing processes and their parameters on the work piece characteristics were determined. Therefore, an interface to a comprehensive manufacturing-orientated technology knowledgemanagement system was created by the first time. In this manner, the required criteria can be calculated on basis of existing technology knowledge. This can be achieved by practical tests, simulations and expert knowledge. As the determined criteria partially show variances which have direct influence on the resulting cost, the variances were considered in the next steps for the first time. Based on the resulting variances and work piece intermediate conditions, in the following a method for the identification of risky processes was presented. Hereunder those manufacturing processes are meant, which disperse without any mathematical law. In that case, an instable process can be assumed and reproducible process results can not be achieved. Similarly, processes resulting in work piece scrap are rejected. The remaining process alternatives are realisable and achieve the given design specifications. They merely differ in their cost and manufacturing times. For this reason, the manufacturing cost and times are being calculated on basis of technology knowledge and the work piece intermediate conditions. The allowed scrap has an essential influence on the cost and times. By defining a limit – alternatively for the scrap, the cost and/ or the times – a calculation of the allowed manufacturing tolerances along the process chain is performed. Finally, the new developed benchmarking of the process alternatives allows a quantitative comparison of the alternatives regarding the criteria cost, time and scrap. As support, the influence of the manufacturing process on the required product objectives and functionalities is being used. Where exists, sometimes already existing methods were used in the modules. This did not affect the development of the framework system for cost-optimal and stable design of process chains. The design of better methods would result in an increased accuracy of the calculated results. Concluding the review of the developed concept has been carried out by implementation within a software-demonstrator and tested by means of a case study
Methodisches System zur Auslegung von kostenoptimalen und prozessstabilen Fertigungsverkettungen
Intention of this task has been to verify that an optimal definition of manufacturing tolerances along the process chain can be achieved by a selective precocious, cost-optimal and stable manufacturing planning. This was carried out by a development of a framework system for the cost-optimal and stable design of manufacturing chains without prior definition of manufacturing tolerances along the process chain. The system starts with the assignment of design specifications with concrete manufacturing processes. A new model was developed, weighting the selected manufacturing processes on basis of their influence on product functionality, work piece characteristics and product purposes. Based on the methods of Fallböhmer and Trommer a manufacturing chain was generated using the selected manufacturing processes. In the following system modules, this manufacturing chain was used as basis for the creation of process alternatives. The process alternatives insist of the same manufacturing processes, which however differ in their parameters and actuating variables. Since the variation of the actuating variables within the allowed spread results in a huge quantity of process alternatives, initially a new model for the alternative reduction was developed. This model is based on the methodology for design of experiments and reduces the existing testing plans. By means of the testing plans, the influences of the manufacturing processes and their parameters on the work piece characteristics were determined. Therefore, an interface to a comprehensive manufacturing-orientated technology knowledgemanagement system was created by the first time. In this manner, the required criteria can be calculated on basis of existing technology knowledge. This can be achieved by practical tests, simulations and expert knowledge. As the determined criteria partially show variances which have direct influence on the resulting cost, the variances were considered in the next steps for the first time. Based on the resulting variances and work piece intermediate conditions, in the following a method for the identification of risky processes was presented. Hereunder those manufacturing processes are meant, which disperse without any mathematical law. In that case, an instable process can be assumed and reproducible process results can not be achieved. Similarly, processes resulting in work piece scrap are rejected. The remaining process alternatives are realisable and achieve the given design specifications. They merely differ in their cost and manufacturing times. For this reason, the manufacturing cost and times are being calculated on basis of technology knowledge and the work piece intermediate conditions. The allowed scrap has an essential influence on the cost and times. By defining a limit – alternatively for the scrap, the cost and/ or the times – a calculation of the allowed manufacturing tolerances along the process chain is performed. Finally, the new developed benchmarking of the process alternatives allows a quantitative comparison of the alternatives regarding the criteria cost, time and scrap. As support, the influence of the manufacturing process on the required product objectives and functionalities is being used. Where exists, sometimes already existing methods were used in the modules. This did not affect the development of the framework system for cost-optimal and stable design of process chains. The design of better methods would result in an increased accuracy of the calculated results. Concluding the review of the developed concept has been carried out by implementation within a software-demonstrator and tested by means of a case study