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Integration der Technologieplanung in die strategische Geschäftsfeldplanung mit Hilfe von Roadmaps
(2017)
A new kind of transistor device with a graphene monolayer embedded between two n-type silicon layers is fabricated and characterized. The device is called graphene-base heterojunction transistor (GBHT). The base-voltage controls the current of the device flowing from the emitter via graphene to the collector. The transit time for electrons passing by the ultrathin graphene layer is extremely short which makes the device very promising for high frequency RF-electronics. The output current of the device is saturated and clearly modulated by the base voltage. Further, the silicon collector of the GBHT is replaced by germanium to improve the device performance. This enabled the collector current to be increased by almost three orders of magnitude. Also, the common-emitter current gain (Ic/Ib) increased from 10-3 to approximately 0.3 for the newly designed device. However, the ON-OFF ratio of the improved germanium based GBHT has so far been rather low. Further optimizations are necessary in order to fully exploit the potential of the graphene-base heterojunction transistor.
Der Berliner Senat hat sich zum Ziel gesetzt bis 2050 klimaneutral zu werden. Das IÖW war bereits an der Machbarkeitsstudie „Klimaneutrales Berlin 2050“ beteiligt. Darauf aufbauend wurde nun das Berliner Energie- und Klimaschutzprogramm entwickelt. Unter der Gesamtprojektleitung des IÖW wurden hierfür gemeinsam mit sieben Partnerinstitutionen konkrete Strategien für die Handlungsfelder Energieversorgung, Gebäude und Stadtentwicklung, Wirtschaft, private Haushalte und Konsum sowie Verkehr erarbeitet. Das Projekt zeichnet sich durch einen breit angelegten Beteiligungsprozess aus, in den sowohl ausgewählte Akteure der Fachöffentlichkeit im Rahmen von Workshops, als auch die breite Öffentlichkeit, hauptsächlich in Form eines Online-Dialoges, miteingebunden werden.
Der Entwurf wurde im Auftrag der Senatsverwaltung für Stadtentwicklung und Umwelt durch ein vom IÖW geführtes Projektteam im Rahmen einer etwa einjährigen Bearbeitungszeit unter Einbeziehung der Berliner Stadtgesellschaft erarbeitet. Er dient als Vorlage für ein vom Senat zu verabschiedendes Programm, welches nach Vorgabe und zur Ergänzung des geplanten Berliner Energiewendegesetzes (EWG Bln) zu erstellen ist.
Bei der hier vorliegenden Veröffentlichung handelt es sich um den Endbericht dieses BEK-Entwurfs, der sämtliche Maßnahmenvorschläge und deren Bewertung beinhaltet.
Research on the psychosocial care (PSC) of unaccompanied minor refugees (UMRs) has mainly taken a socioepidemiological approach and has focused on the perspectives of experts in the field. In contrast, the knowledge concerning the differing context factors and the underlying mechanisms of current PSC which could inform policy recommendations is scant. The study aims at unravelling the contexts, mechanisms and outcomes of PSC for UMRs. For a realist review (RR), scientific evidence and gray literature were synthesised consistent with the RAMESES publication standards for realist synthesis. Based on an iterative keyword search in electronic databases (e.g., PubMed) and screening, 34 works from 2005 to 2019 were included in a realist synthesis. Theory-informed context-mechanism-outcome configurations (CMOs) were extracted, to explain underlying processes and mechanisms. Characterised by their interrelatedness, the dominant CMOs included the UMRs' intersections of transitions (e.g., adolescence and migration), their needs for culture-, and gender-sensitive PSC, and the undersupply of PSC. These contexts and outcomes are mediated by pre-, peri- and post-migratory stressors as well as care structures and are moreover influenced by overarching discourses and concepts. They comprise adverse and beneficial mechanisms in the PSC of UMRs. The existing literature grasps the PSC of UMRs by different disciplines and approaches but does not offer a comprehensive overview on micro-macro intersections and included discourses. The inclusion of lay perspectives and an intersectional approach could inform health service research. The reflection of UMR-related categorical constructs of resilience and vulnerability, discourses of othering, as well as restrictive health policies may guide policy recommendations.
Der Berliner Senat hat sich zum Ziel gesetzt bis 2050 klimaneutral zu werden. Das IÖW war in diesem Zuge bereits an der Machbarkeitsstudie „Klimaneutrales Berlon 2050“ beteiligt. Darauf aufbauend wurde nun das Berliner Energie- und Klimaschutzprogramm entwickelt. Unter der Gesamtprojektleitung des IÖW wurden hierfür gemeinsam mit sieben Partnerinstitutionen konkrete Strategien für die Handlungsfelder Energieversorgung, Gebäude und Stadtentwicklung, Wirtschaft, private Haushalte und Konsum sowie Verkehr erarbeitet. Das Projekt zeichnet sich durch einen breit angelegten Beteiligungsprozess aus, in den sowohl ausgewählte Akteure der Fachöffentlichkeit im Rahmen von Workshops, als auch die breite Öffentlichkeit, hauptsächlich in Form eines Online-Dialoges, miteingebunden werden.
Der Entwurf wurde im Auftrag der Senatsverwaltung für Stadtentwicklung und Umwelt durch ein vom IÖW geführtes Projektteam im Rahmen einer etwa einjährigen Bearbeitungszeit unter Einbeziehung der Berliner Stadtgesellschaft erarbeitet. Er dient als Vorlage für ein vom Senat zu verabschiedendes Programm, welches nach Vorgabe und zur Ergänzung des geplanten Berliner Energiewendegesetzes (EWG Bln) zu erstellen ist.
Der technische Anhang bietet einen zusätzlichen Einblick in die methodische Herangehensweise als Ergänzung zum Hauptbericht und Anhang A.
Germanium (Ge) nanowires (NWs) were grown in-plane on nano-structured Si(001)/SiO2
substrates by molecular beam epitaxy using gold (Au) as the solvent. The site-selective NW growth was enabled by a rectangular array of gold droplets on silicon (Si) tips with an Au nuclei density
below 0.25 μm−2 on the surrounding silicon oxide (SiO2). The initial growth of Ge NWs starting from Si–Au droplets with SixGe1−x nucleation from ternary alloy is discussed from a thermodynamic point of view. The in-plane NW elongation occurred within ⟨110⟩ directions on the substrate and NWs were mainly bounded by two 55◦ inclined 111 facets and a less pronounced planar (001) top facet. Fully relaxed crystal lattices of Ge NWs were observed from two-dimensional reciprocal space maps of x-ray diffraction measurements.
Introduction: Several studies have identified that unaccompanied minor refugees (UMRs) are allegedly ‘vulnerable’ and belong to a high-risk group in terms of psychological distress and post-traumatic stress disorder due to their preflight, periflight and postflight experiences. Psychosocial care (PSC) is of high importance for UMRs, but little is known about barriers to access and utilisation of PSC across place and gender. The aims of this gender-sensitive qualitative study will be to build on the existing body of literature and to provide qualitative evidence on the contexts and mechanisms of PSC for male and female UMRs in Germany by comparing two German regions.
Methods and analysis: Following the study preparing realist review, a qualitative study will be undertaken in Berlin and Central German cities. Approximately 24 experts from the field of PSC and 12 lay UMRs will participate in face-to-face, semistructured interviews. Data will be transcribed and analysed based on the grounded theory research paradigm.
Ethics and dissemination: Only participants who have been informed in both German and their native tongue and who have signed a declaration of consent will be included in the study. The study will comply rigorously with German data protection standards. Approval from the Ethical Review Committee at Martin Luther University Halle-Wittenberg, Germany has been obtained and granted. The results of the study will be presented at several conferences and will be published in high-quality, peer-reviewed international journals. The results will display a differentiated picture of the PSC of UMRs in Germany. Such knowledge is a precondition for a ‘science of change’ that translates explanations into practical recommendations on how to improve healthcare policies.
A graphene-based three terminal barristor device was proposed to overcome the low on/off ratios and insufficient current saturation of conventional graphene field effect transistors. In this study, we fabricated and analyzed a novel graphene-based transistor, which resembles the structure of the barristor but uses a different operating condition. This new device, termed graphene adjustable-barriers transistor (GABT), utilizes a semiconductor-based gate rather than a metal−insulator gate structure to modulate the device currents. The key feature of the device is the two graphene-semiconductor Schottky barriers with different heights that are controlled simultaneously by the gate voltage. Due to the asymmetry of the barriers, the drain current exceeds the gate current by several orders of magnitude. Thus, the GABT can be considered an amplifier with an alterable current gain. In this work, a silicon−graphene−germanium GABT with an ultra-high current gain (ID/IG up to 8 × 106) was fabricated, and the device functionality was demonstrated. Additionally, a capacitance model is applied to predict the theoretical device performance resulting in an on−off ratio above 106, a swing of 87 mV/dec, and a drivecurrent of about 1 × 106 A/cm2.
This paper gives insights on the usability of single priority and multi-criteria dispatching rules for production scheduling based on the results for a German chipboard manufacturing plant. A discrete-event simulation of the manufacturing process has been modeled to compare different priority rules with an expert-based sequence for a real set of jobs. The simulation results show that using one single or multi criteria priority dispatching rule on the total production system basically leads to a poor performance, whereas using different rules for each machine will enhance the overall performance. Higher performance can be achieved by the expert based scheduling and individual multi criteria dispatching rules. Hence, a dynamic modification of the production schedule by switching the dispatching rules according to the current performance is proposed, considering unforeseen disturbances.
This paper evaluates storage batteries with respect to usage in hybrid shunting locomotives. Topics are the status quo of existing technologies as well as future electrochemical storage technologies. A target system is used to evaluate the technologies. Furthermore, relevant battery characteristics for the usage in hybrid shunting locomotives have been identified. The necessary data have been retrieved from current literature (document analysis) and by a survey made with scientific and industrial experts. The results of the study show, that batteries of the lithium-ion-technology with a lithium-titanate anode and a lithium-iron-phosphate cathode are currently the most suitable batteries for the use in hybrid shunting locomotives. Promising future technologies are under investigation, but these technologies are several years away from their market entry.