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Geschäftsmodellentwicklung für wohnbegleitende Dienstleistungen im Technikunterstützten Leben (AAL)
No full textEs wird die Geschäftsmodellentwicklung für wohnbegleitende Dienstleistungen im Technikunterstützten Leben (Ambient Assisted Living, AAL) mit insgesamt sechs DIN Spezifikationen (DIN SPEC), Dienstleistungen im Technikunterstützten Leben und Aufbau eines Geschäftsmodells für wohnbegleitende Dienstleistungen beschrieben. Neben der Erstellung und Umsetzung des dreistufigen Geschäftsmodells wurde eine entsprechende Informations- und Kommunikationsinfrastruktur für wohnbegleitende Dienstleistungen betrachtet
Car-borne tracking of fissile material by covert search procedures
No full textThe recovery of fissile or radiological material illegally removed from its site of operation or storage is tremendously important in the context of the possible threat of nuclear terrorism. The material must be retrieved prior to its potential use in Radiological Dispersal Devices (RDD) or Improvised Nuclear Devices (IND). The process of tracking the material during transport or storage by means of a covert search is preferable to an open search as it does not draw the attention of civilians, thus preventing counter-productive reactions of panic by the general public or even early release by the terrorists. The Fraunhofer-INT has engineered a measurement system with an additional battery powered energy supply which can be integrated in a standard station wagon, featuring built-in gamma and neutron detection techniques as well as portable detection devices. It is therefore well-suited for covert search routines with respect to nuclear or radiological material which is transported across or stored in residential or industrial areas. Realistic case scenarios were investigated where nuclear or radioactive material was concealed on a test area, partly even inside buildings. At first, the rough location of the material was determined by means of the car's built-in detection system from inside the vehicle. Then the search for the exact location was continued on foot, using a portable detector which provides the opportunity to locate and subsequently identify the material in question. This way a thorough search of an area where such material is suspected was conducted. The search strategies as well as the results of these search procedures are presented
Detecting fissionable material from a travelling vehicle by neutron coincidence measurements
No full text7 S.For the search and detection of concealed nuclear material we equipped a conventional car with a neutron measurement system. It consists of six neutron slab counters on each side and the appropriate electronics. The complete system can easily be fixed in most vehicles. The pulses of the six modules on each side are summed passively and each side is analyzed separately. The results are displayed on a handheld pe in the front of the car or, in case of a covered search, the data are stored in a non-volatile memory together with coordinate information from GPS. In order to verify the presence of fissionable material, we investigated the possibility to detect two or more neutrons in coincidence. In this way it is possible to distinguish industrial neutron sources like Am/Be(n) from Special Nuclear Material. First the material is localized by its total rate from the moving vehicle. Then the vehicle is stopped in the vicinity of the suspicious location and the coincidences are counted for a period of 10 to 1000 seconds depending on neutron intensity and distance. At a distance of I meter, a quantity of gof weapon-grade plutonium can be detected in 1000 seconds, corresponding to 0.5 g reactor plutonium, in 10 seconds the detection limit is 200 g. In case of a concrete shielding of 10 cm thickness the detection limit is increased to 6.3 g in 1000 seconds and OA7 kg for an interval of 10 seconds. With 20 cm concrete shielding these values are approximately doubled. Larger quantities of weapon-grade or reactor plutonium (kilograms) can also be identified out of the moving vehicle. This system may be used to discover illicit trafficking of nuclear material and thus prohibit nuclear proliferation
Detection of concealed fissionable material by delayed neutron counting
No full textS.139-140We performed measurements with a small, light-weight neutron generator, which can be carried by one person. The time structure of delayed neutrons was measured in order to detect and identify hidden or shielded nuclear material in geometrical configurations whereof only the outer shape is known but little or no information is available on the inner structure. A small block of depleted uranium was irradiated repeatedly by a sealed neutron tube of a 14 MeV neutron generator for different time intervals. The delayed neutrons were measured by a neutron "slab" counter consisting of 6 He-3 tubes moderated by high density polyethylene. After the end of each interrogating neutron pulse we analyzed the delayed neutrons in different time intervals, ranging from 3 s to 300 s and thus recorded the "decay curves" of the delayed neutrons. We optimized neutron irradiation and measuring time to gain information on the existence of fissionable material in a short time. These experiments show that fissionable material can be detected clearly and easily in a suspicious object without any information on the inner geometry and the surrounding moderating material within a very short time (several minutes)
Covert search and detection of illicit nuclear as well as radioactive material
No full textS.176-185To prevent the misuse of nuclear or radioactive material for malicious acts we investigated highly sensitive passive detection systems for gamma and neutron radiation. The aim is to detect such material as early as possible with high reliability excluding false alarms caused by natural radioactivity (like in potash fertilizer) or by patients which have undergone a nuclear medical therapy respectively examination. Fixed monitors can be employed for the detection of such materials during transport. They may be covertly installed in advertising pillars or other objects commonly found in public. In a more static situation a general overview is gained by scanning of buildings or objects with a gamma camera. Here the measured spatial gamma intensity is converted into colors and then superimposed on the optical picture of the situation in order to get a visual overview. Besides gamma detectors we investigated neutron detectors also. Nuclear material can be detected by neutron emissions from spontaneous fission as well as by the neutrons produced by (alpha,n) reactions in surrounding material. Therefore we operate a sensitive neutron detection system, fitted into a hand pulled suitcase. With a special analysis procedure it is possible to categorize the substance in fissionable and non-fissionable material. In addition, the system can discover the existence of shielding material located around the source material. The presence of shielding material often gives important information for the evaluation of the possible risk. Furthermore a specific search can be executed when a concrete suspicion arises. Therefore we investigated the characteristics of small, hand-held devices for in field operation
Recent improvements in on-site detection and identification of radioactive/nuclear material
No full text24 FolienSensitive mobile detection systems are important to detect and prevent illicit trafficking of radioactive and nuclear material. Recently, new mobile systems for low and high resolution gamma detection have become available which have new features that enhance the detection possibilities and ease the use of hand-held systems. One improvement is the utilization of improved scintillation material like Lanthanum Bromide (LaBr3) which offers a factor of 2-3 in energy resolution compared to the widely used Sodium Iodide (NaI). An other enhancement is the use of Stirling Coolers for High Purity Germanium (HPGe) detectors which now have become lighter and more reliable and allow building high resolution detectors without the need for liquid nitrogen. These systems are really portable now and can be used as mobile search devices. Such devices have been investigated also. On the other hand also new mobile neutron detection systems came on the market which comprise advanced detection and, to some extend, also identification methods. Although mobile neutron detection systems are less common in typical mission scenarios they play an important role in some special cases, in particular if nuclear material is involved. Because the use of an improvised nuclear device (IND) by terrorists may have vast consequences the identification of nuclear material in such a special device is extremely important. Nuclear material can be identified by the detection of coincidence neutrons or, although with less constraint, also by evaluating the neutron spectra. Devices using both methods, which are hand-held or at least portable, have been investigated
Natural Fiber-Reinforced Composite Incorporated with Anhydride-Cured Epoxidized Linseed-Oil Resin and Atmospheric Pressure Plasma-Treated Flax Fibers
No full textFiber-reinforced composites (FRCs) represent a promising class of engineering materials due to their mechanical performance. However, the vast majority of FRCs are currently manufactured using carbon and glass fibers, which raises concerns because of the difficulties in recycling and the reliance on finite fossil resources. On the other hand, the use of natural fibers is still hampered due to the problems such as, e.g., differences in polarity between the reinforcement and the polymer matrix components, leading to a significant decrease in composite durability. In this work, we present a natural fiber-reinforced composite (NFRC), incorporating plasma pre-treated flax fibers as the reinforcing element, thermoplastic polylactic acid (PLA) as a matrix, and a key point of the current study—a thermoset coating based on epoxidized linseed oil for adhesion improvement. Using atmospheric plasma-jet treatment allows for increasing the fiber’s surface energy from 20 to 40 mN/m. Furthermore, a thermoset coating layer based on epoxidized linseed oil, in conjunction with dodecyl succinic anhydride (DDSA) as a curing agent and 2,4,6-tris(dimethyl amino methyl) phenol (DMP-30) as a catalyst, has been developed. This coated layer exhibits a decomposition temperature of 350 °C, and there is a substantial increase in the dispersive surface-energy part of the coated flax fibers from 8 to 30 mN/m. The obtained natural fiber-reinforced composite (NFRC) was prepared by belt-pressing with a PLA film, and its mechanical properties were evaluated by tensile testing. The results showed an elastic modulus up to 18.3 GPa, which is relevant in terms of mechanical properties and opens up a new pathway to use natural-based fiber-reinforced bio-based materials as a convenient approach to greener FRCs.171
Sensor-Derived Parameters from Standardized Walking Tasks Can Support the Identification of Patients with Parkinson’s Disease at Risk of Gait Deterioration
No full textBackground: People with Parkinson’s disease suffer from gait impairments. Clinical scales provide a limited and rater-dependent assessment of gait. Wearable sensors allow an objective characterization by capturing rhythm, pace, and signature patterns. This study investigated if sensor-derived gait parameters have prognostic value for short-term progression of gait impairments. Methods: A total of 111 longitudinal visit pairs were analyzed, where participants underwent clinical evaluation and a 4 × 10 m walking test instrumented with wearable sensors. Changes in the UPDRSIII gait score between baseline and follow-up were used to classify participants as Improvers, Stables, or Deteriorators. Baseline group differences were assessed statistically. Machine-learning classifiers were trained to predict group membership using clinical variables alone, sensor-derived gait features alone, or a combination of both. Results: Significant between-group differences emerged. In participants with UPDRSIII gait score = 1, Improvers showed higher median gait velocity ((Formula presented.)) and stride length ((Formula presented.)) than Stables ((Formula presented.) ; (Formula presented.)) and Deteriorators ((Formula presented.) ; (Formula presented.)), along with lower stance time variability (3.10% vs. 4.49% and 3.75%; all (Formula presented.)). The combined sensor-based and clinical model showed the best performance (AUC (Formula presented.)). Conclusions: Integrating sensor-derived gait parameters with clinical score can support the identification of patients at risk of gait deterioration in the near future.13
Characterization of Freshly Isolated Human Peripheral Blood B Cells, Monocytes, CD4+ and CD8+ T Cells, and Skin Mast Cells by Quantitative Transcriptomics
No full textQuantitative transcriptomics offers a new way to obtain a detailed picture of freshly isolated cells. By direct isolation, the cells are unaffected by in vitro culture, and the isolation at cold temperatures maintains the cells relatively unaltered in phenotype by avoiding activation through receptor cross-linking or plastic adherence. Simultaneous analysis of several cell types provides the opportunity to obtain detailed pictures of transcriptomic differences between them. Here, we present such an analysis focusing on four human blood cell populations and compare those to isolated human skin mast cells. Pure CD19+ peripheral blood B cells, CD14+ monocytes, and CD4+ and CD8+ T cells were obtained by fluorescence-activated cell sorting, and KIT+ human connective tissue mast cells (MCs) were purified by MACS sorting from healthy skin. Detailed information concerning expression levels of the different granule proteases, protease inhibitors, Fc receptors, other receptors, transcription factors, cell signaling components, cytoskeletal proteins, and many other protein families relevant to the functions of these cells were obtained and comprehensively discussed. The MC granule proteases were found exclusively in the MC samples, and the T-cell granzymes in the T cells, of which several were present in both CD4+ and CD8+ T cells. High levels of CD4 were also observed in MCs and monocytes. We found a large variation between the different cell populations in the expression of Fc receptors, as well as for lipid mediators, proteoglycan synthesis enzymes, cytokines, cytokine receptors, and transcription factors. This detailed quantitative comparative analysis of more than 780 proteins of importance for the function of these populations can now serve as a good reference material for research into how these entities shape the role of these cells in immunity and tissue homeostasis.252
Aluminum-Aluminum Wafer Level Thermo Compression Bonding Using Thick Electroplated Aluminum Bonding Frames
No full textWafer bonding is crucial in semiconductor manufacturing, integrating diverse materials and creating complex devices. Aluminum thermo-compression bonding (Al TCB) is promising for its high bond strength, easy integrability into production process chains, and reliability, essential for advanced packaging and MEMS. This study investigates thick (>4 μm) electroplated aluminum layers, both as-deposited and planarized, under varying conditions. As-deposited surfaces with asperities show high dicing yields above 90 % and strong shear strengths above 40 N/mm2, while planarized surfaces require higher temperatures to achieve comparable shear strength. The findings emphasize the role of surface roughness on bond quality and provide insights for optimizing Al TCB processes in semiconductor manufacturing