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Environmental friendly and low cost monitoring system for plant and agriculture fields
No full textThe constantly growing global population is to be sustainably supplied with food. Due to climatic changes and increasing problems in protecting the environment, farmers are faced with great challenges. In order to automate, specify and simplify processes, reliable decision-making bases for the control of irrigation, fertilization and plant protection measures with a close-meshed database are required. This can be achieved with cost-efficiently produced and environmentally friendly sensor systems for monitoring cultivated areas. Such a monitoring system is currently being developed, first laboratory samples are available and are being tested step by step in laboratory and field. The single sensor devices consist of a miniaturized electronic module with single-chip radio system, sensors for measuring temperature, soil tension, in the near future leaf wetness and nitrate. The sensors and the electronic module are fabricated from materials that are biodegradable or inert with a minimum amount of metal and ceramic and allow for remaining them on the field when harvesting. The device is powered by a biodegradable zinc-manganese dioxide battery. For wireless communication, a printed antenna on a wood carrier is used. A gateway collects the data transmitted by the distributed sensor devices and brings it to the internet to a central server running an expert system. The technologies used for the assembly, such as roll-to-roll and screen printing, and the materials used, such as wood and paper, enable inexpensive and partly biodegradable sensors that are applied to the field once per growing season in high density. This enables fine-mesh, site-specific treatments and a further reduction in water, fertiliser and pesticide use
Optimized quality and process control through AI-based image classification at Fraunhofer IPMS
No full text311313Optical defect inspection and classification is an important part of semiconductor manufacturing. They provide relevant information to correct process problems and thus improve product yield and quality. The highly automated inspection and microscopy systems generate an enormous amount of data. AI-based methods are an appropriate way to ensure 100% classification coverage, to improve monitoring accuracy and to support anomaly detection. Initial experience with the use of an AI-based system for optical image classification was gained in the cleanroom environment of Fraunhofer IPMS in Dresden
Effiziente Kleinserienfertigung eines Türspantes in Blechbauweise mittels RoRoFo
No full textDie Herstellung von Aluminiumtürspanten erfolgt zumeist mittels Fräsen aus einem großen Block, dabei treten Spanvolumina von über 90% auf. In dieser Arbeit wird ein Türspantdesign in Blechbauweise vorgestellt, das mit über 90 % Materialnutzungsgrad und damit unter 10 % Verschnitt deutlich materialeffizienter ist. Um bei dieser Bauweise auch bei geringen Stückzahlen eine effiziente Fertigung zu gewährleisten, wurde ein roboterbasierter Rollformprozess (RoRoFo) entwickelt und genutzt. Hierbei fährt ein von einem Knickarmroboter geführter Endeffektor mit Doppelrollensatz entlang einer FE-optimierten Biegekurve und formt das Blech inkrementell um. Zur Maximierung der Fertigungseffizienz und insbesondere der Absicherung der Form- und Lagetoleranzen von Blechbauteilen wird des Weiteren ein Ansatz beschrieben, mit welchem Richtprozesse in die finalen Umforminkremente integriert werden können.The production of aluminum door frames is typically carried out by milling from a large block, resulting in chip volumes exceeding 90%. This work presents a sheet metal door frame design that is significantly more material-efficient, with a material utilization rate of over 90% and thus less than 10% waste. To ensure efficient production even with small batch sizes, a robot-based roll forming process (RoRoFo) was developed and implemented. In this process, an end effector with a double roller set, guided by an articulated robot arm, travels along an FE-optimized bending curve and incrementally forms the sheet metal. To maximize production efficiency and, in particular, to ensure the form and positional tolerances of sheet metal components, an approach is further described that integrates straightening processes into the final forming increments
Rapid virus-free production of recombinant yellow fever virus envelope protein and its in-depth biophysical analysis
No full textThe aim of this study was to develop a rapid and easy-to-adapt protocol for recombinant production of Orthoflavivirus proteins. We introduced the new-generation pOpiE2 vector for virus-free transient transfection of Trichopluisa ni High Five insect cells to produce the envelope protein ectodomain of Yellow Fever Virus Asibi and 17D strains. We achieved high yields in the range of 6–7 mg/L within five working days. In-depth biophysical analysis demonstrated highest protein purity, homogeneity, stability, and affinities to specific antibodies in the low nanomolar range. A combination of peptide mass fingerprint and intact mass spectrometry characterized the copurified precursor chaperone peptide pr and discovered a new posttranslational processing site for the recombinantly produced protein.15
Adverse effects of ozonation on the animal welfare of tilapia Oreochromis niloticus in recirculation aquaculture
No full textOzone is often used to disinfect process water in recirculating aquaculture systems. Here, ozone rapidly leads to the formation of secondary oxidants, called ozone produced oxidants (OPO). We studied the impact of OPO on juvenile tilapia Oreochromis niloticus in brackish water at 0, 0.05, 0.1 and 0.15 mg/L chlorine equivalents after 2 d, 9 d and 21 d of exposure, assessing gill histopathology and lesions of the mitochondrial DNA. Damage of the gills was already observed after 2 d, comprising an increased occurrence of lamellar lifting, fusion of the lamellae and edema at 0.15 mg/L. After 21 d, occurrence of lamellar fusion and edema was elevated at 0.15 mg/L. Increased incidence of hyperplasia was already observed at 0.05 mg/L after 9 d. DNA fragmentation increased to 3.92 lesions per 10 kb at 0.15 mg/L compared to 2.62 lesions per 10 kb in the control. In conclusion, first adverse effects were observed at 0.05 mg/L and severe impact is subsequently recorded at 0.1 mg/L chlorine equivalents. Therefore, OPO concentrations need to be kept below 0.05 mg/L chlorine equivalents to avoid adverse effects on animal welfare.3
Implementierung von KI-Algorithmen zur Anomaliedetektion in PV-Anlagen und Aufbau einer Leitwartenapplikation
No full textMaximising energy yield and ensuring reliable operation are key challenges for photovoltaic (PV) systems. Using artificial intelligence (AI) for the early detection of anomalies such as shading can significantly minimise losses. This thesis analyses the suitability of Support Vector Machines (SVMs) and Convolutional Neural Networks (CNNs) for detecting shading faults in a real PV system at the Fraunhofer IFF. As part of this process, a supporting monitoring dashboard is being developed. Four scenarios involving different levels of feature engineering were compared using data from inverters and weather stations. The SVM models consistently showed better performance and were significantly more computationally efficient (47 seconds vs. nearly six hours) than the CNNs. The results of the study show that a targeted configuration of specific technical features leads to a significant increase in performance. The analysis revealed that an SVM with minimal feature processing achieved optimal results, with an accuracy of 82,06% on the test data. The best CNN model achieved an accuracy of 80,62%. The developed dashboard successfully integrates the best SVM model and improves the transparency of the results with the help of explainable artificial intelligence (XAI). The work demonstrates the potential of AI algorithms for efficient shading detection and provides a functional dashboard application
Optimizing Magnetic Properties of Ce-containing Nd-Fe-B-based Magnets through 2-Powder Method
No full textZONAL MODEL VALIDATION FOR AN ENVIRONMENTALLY FRIENDLY AIRCRAFT CARGO FIRE PROTECTION SYSTEM WITH CONTAINERIZED LOAD
No full text58635873Today's cargo bays use halon as fire suppression agent. However, due to the high ozone depletion potential of this chemical, alternative solution are researched. Within this framework, the cargo bay in the Fraunhofer Flight Test Facility has been equipped with a nitrogen based fire suppression system to investigate the local distribution of oxygen and nitrogen concentrations. This paper focusses on the system performance when empty or loaded with geometrically equivalent LD3 container elements that replicate the flow blockage for the fire suppression agents in the cargo hold. Furthermore, the test data is used to validate a zonal model predicting the local distribution of agents in the cargo hold. This simulation tool has been developed within the CleanSky2 Environmentally Friendly Aircraft Cargo Fire Protection System
Use of Different Process Gases for Manufacturing Isolating Alumina Coatings by Flame Spraying with Cords
No full text648656Besides conventional industrial demands, thermally sprayed coatings are increasingly used for innovative products, such as additive manufacturing of electrical components in automotive engineering. In particular, heating units are manufactured by a combination of various spray technologies. At present, simpler spraying processes like flame spraying are investigated with regard to their suitability as a future cost-effective alternative for fabricating isolating alumina coatings. In this study, alumina cords were flame-sprayed using compressed air and argon as atomizing gases. The results demonstrate fine microstructures and a partially even higher surface and volume resistivity compared to past investigations in the literature. Furthermore, the content of alpha phase is higher than for plasma-sprayed coatings, regardless of the atomizing gas used. Moreover, flame-sprayed coatings using argon reveal a higher resistivity in comparison to coatings sprayed with air. In addition to the phase composition and kinematics, it can be concluded that humidity plays a major role in coating properties
Chronic prurigo Chronische Prurigo
No full text889898Chronic prurigo is a very debilitating skin condition characterized by the development of multiple pruriginous nodules, papules or plaques due to a prolonged scratching behavior as a result of chronic itch. Patients often experience anxiety, depression or sleep impairment leading to a substantial decrease in quality of life. Due to the complex pathophysiology and diversity in clinical presentation, managing chronic prurigo remains a challenge. Disease-specific guidelines provide appropriate diagnostic measures and recommend a step-wise therapeutic approach. With the increase of pharmaceutical interest in chronic prurigo, several innovative therapies including monoclonal antibodies and small molecules are currently being investigated for chronic prurigo. This continuing medical education (CME) article provides an overview on various aspects of chronic prurigo, especially on epidemiology, pathophysiology, clinical presentation, diagnostic and therapeutic approach, and innovate therapeutic options.741