cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Regenerative Soot-III: Role of the kinetic and potential sputtering in the regeneration of the soot
Creators: name: Ahmad, Shoaib
name: Akhtar, M. N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We have used the photoemission spectroscopy of the graphite hollow cathode sooting discharge to identify the roles played by the kinetic and potential sputtering, respectively. Our indicators are the relative densities of the sputtered carbon C, the Ne metastable atoms, and the ionized components (Ne+) of the regenerative sooting plasma. We find that the metastable atoms are the main agents for the regeneration of the soot.
description: 6 pages, 3 figures
Do We Really Understand the Cosmos?
Creators: name: Padmanabhan, T.
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Our knowledge about the universe has increased tremendously in the last three decades or so --- thanks to the progress in observations --- but our understanding has improved very little. There are several fundamental questions about our universe for which we have no answers within the current, operationally very successful, approach to cosmology. Worse still, we do not even know how to address some of these issues within the conventional approach to cosmology. This fact suggests that we are missing some important theoretical ingredients in the overall description of the cosmos. I will argue that these issues --- some of which are not fully appreciated or emphasized in the literature --- demand a paradigm shift: We should not think of the universe as described by a specific solution to the gravitational field equations; instead, it should be treated as a special physical system governed by a different mathematical description, rooted in the quantum description of spacetime. I will outline how this can possibly be done.
description: Invited Review; 28 pages; 1 figure
Model-based evaluation of scientific impact indicators
Creators: name: Medo, Matus
name: Cimini, Giulio
Publisher: name: arXiv
Year: 2016
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Digital Libraries (cs.DL)
subject: Social and Information Networks (cs.SI)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Using bibliometric data artificially generated through a model of citation dynamics calibrated on empirical data, we compare several indicators for the scientific impact of individual researchers. The use of such a controlled setup has the advantage of avoiding the biases present in real databases, and allows us to assess which aspects of the model dynamics and which traits of individual researchers a particular indicator actually reflects. We find that the simple citation average performs well in capturing the intrinsic scientific ability of researchers, whatever the length of their career. On the other hand, when productivity complements ability in the evaluation process, the notorious $h$ and $g$ indices reveal their potential, yet their normalized variants do not always yield a fair comparison between researchers at different career stages. Notably, the use of logarithmic units for citation counts allows us to build simple indicators with performance equal to that of $h$ and $g$. Our analysis may provide useful hints for a proper use of bibliometric indicators. Additionally, our framework can be extended by including other aspects of the scientific production process and citation dynamics, with the potential to become a standard tool for the assessment of impact metrics.
description: 12 pages, 8 figures
Dry deep drawing of aluminum for automotive production
Creators: name: Prieske, Markus
name: Börner, Richard
name: Berger, Thomas
name: Kühn, Ralf
name: Scholz, Peter
name: Schubert, Andreas
name: Müller, Roland
name: Vollertsen, Frank
Publisher: name: Universität Bremen
Year: 2020
Subjects: subject: CVD diamond
subject: friction
subject: doping
subject: ultrasonic vibration assisted milling
subject: electrical discharge machining
subject: microstructuring
subject: sheet metal forming
subject: dry metal forming
subject: coefficient of friction
subject: 620

description: Lubricants are commonly used in metal forming processes to reduce the friction between the workpiece and the forming tool to protect semi-finished products and goods against corrosion and to reduce the load on the tool. One aim of environmentally friendly production technologies is to achieve dry forming without the use of lubricants. The goal of this project is to enable the dry forming of aluminum alloys during deep drawing by locally increasing the tool load capacity using customized tool coatings. The suitability of two types of carbon-based coatings, amorphous carbon and CVD diamond coatings will be investigated for dry contact with aluminum. In addition to coating, tribological effective microstructuring should improve the material flow and wear resistance of the used tools. The advantage of the amorphous carbon coatings is the deposition process, which enables a large area deposition as well as a good adhesion strength on steel substrates. Dry strip drawing and deep drawing tests with amorphous carbon coated tools showed higher friction coefficients compared to lubricated tests without any coating and a high adhesive wear. A reduction of the contact ratio from 100% to 87.5% resulted in a decrease of the sliding friction value by 20%. Dry tribological ball-on-plate tests of different coatings against aluminum showed that a polished microcrystalline CVD diamond coating is most promising to enable dry aluminum forming with a long lifetime of the coated tool. By in situ silicon carbide sublimation in a diamond deposition process, a possibility has been demonstrated for atmospheric CVD processes to reduce the electrical resistance of CVD diamond layers without the use of toxic gases. The electrical resistance of the coating could be reduced with a silicon doping concentration in the order of 1020 cm-3 in range between 104 Ω and 106 Ω. Electrical discharge machining of CVD diamond coatings has been made possible by silicon doping, which means that the specific resistance has been reduced to below 100 Ω∙cm.
The importance of hot Jupiters in stellar clusters for understanding planet formation
Creators: name: Winter, Andrew
Publisher: name: Zenodo
Year: 2022
Subjects: hot Jupiters
exoplanets
planet formation
stellar clusters

description: Hot Jupiters (HJs) are short period massive planets that must accumulate the majority of their mass in the outer disc. They may arrive at their current orbits via low eccentricity migration within a disc, or via tidal circularisation during close approach with the host star if a sufficiently high eccentricity can be produced (high eccentricity migration, HEM). In this talk, I show that a planet's eccentricity behaves in a diffusive way in dense stellar environments, leading to a predictable yield of HJs via HEM. This theory predicts a peak of HJ production at stellar densities ~10^4 stars/pc^3, simultaneously explaining the apparent dearth of HJs in 47 Tuc versus an overabundance in M67. More generally, I show that constraining the population of short period planets puts direct constraints on the efficiency of outer planet formation in stellar clusters. Better statistics of planets in stellar clusters is therefore an important goal for constraining planet formation theory.
Ambivalenzen betrieblicher Krisenbewältigung
Creators: name: Klöpper, Arne
name: Holtrup, André
Publisher: name: Universität Bremen
Year: 2011
Subjects: subject: Beschäftigungspolitik
subject: Atypische Beschäftigungsverhältnisse
subject: 330

description: Welche Mechanismen, Maßnahmen und Verfahren haben deutsche Betriebe angewandt, um ihre Beschäftigungspolitiken an die Wirtschaftskrise in den Jahren 2008 und 2009 anzupassen? Welche Auswirkungen auf die Arbeitsbeziehungen auf der betrieblichen und überbetrieblichen Ebene lassen sich feststellen? Dies waren die zentralen Fragen eines empirischen Forschungsprojekts, dass sich auf die Beschäftigungspolitiken in Betrieben der Automobil(zuliefer)industrie und Logistik konzentrierte. Die Befunde deuten darauf hin, dass insbesondere der milde Verlauf der Wirtschaftskrise und die ausgiebige Nutzung des Instruments Kurzarbeit das sozialpartnerschaftliche Modell der Arbeitsbeziehungen in Deutschland gestärkt haben. Die betrieblichen Akteure sind – zumindest vorübergehend – „zusammengerückt“ und haben Lösungen gewählt, die die Kernbelegschaften vor negativen Konsequenzen und den gestiegenen Marktrisiken bewahrten. Die betrieblichen Beschäftigungspolitiken in der Krise haben somit zu einer Schließung der Kernzone der Beschäftigung beigetragen. Sowohl Managements als auch Betriebsräten und Kernbelegschaften erscheinen Formen atypischer und unsicherer Beschäftigung (Befristungen, Zeitarbeit) teilweise als adäquate Instrumente, um die personalpolitische Flexibilität zu steigern und die Beschäftigungsperspektiven der Kernbelegschaft abzusichern. So ist zu erwarten, dass sich zukünftig die Nutzung atypischer Beschäftigungsverhältnisse und damit die Segmentation von Beschäftigtengruppen verstärkt.
Zur Bedürftigkeit von Aufstocker-Familien
Creators: name: Schröter, Anne
Publisher: name: Universität Bremen
Year: 2012
Subjects: subject: Grundsicherung
subject: 320

description: 1,16 Mio. Familien bezogen im Jahr 2010 Leistungen nach dem SGB II. Davon verfügten 30 Prozent über ein eigenes Einkommen. Das heißt, dass diese Familien trotz eines eigenen Einkommens als arm zu bezeichnen sind und auf Transferzahlungen angewiesen sind. Diese sogenannten Aufstocker-Familien stehen im Rahmen des vorliegenden Beitrags im Vordergrund. Auffällig ist, dass Aufstocker-Familien zu 88 Prozent nur über ein Einkommen, im Sinne des traditionellen Familienmodells, verfügten. Dies begründet die Ausgangsthese, dass im Besonderen das traditionelle Familienmodell zu einer erhöhten Bedürftigkeitslage beiträgt und damit auch als Ursache für die Bedürftigkeit von Familien herangezogen werden kann. Neben der Frage nach dem Einfluss des Familienmodells soll die Rolle der sozialstaatlichen Instrumente dabei in den Blick genommen werden. So wird der Frage nach dem Einfluss ausgewählter sozialstaatlicher Instrumente auf das Familienmodell und die Bedürftigkeitssituation von Familien nachgegangen. Das Diskussionspapier zeigt damit die Gründe für Bedürftigkeit von Familien auf und weist auf ambivalente Strukturen und Unterstützungsinstrumente des deutschen Sozialstaates hin.
Crafting skills and values : a study of institutional dynamics
Creators: name: Minahan., Stella Marie
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Beschäftigung, Auftragslage und Perspektiven im deutschen Schiffbau : [Ergebnisse der 21. Betriebsrätebefragung im September 2012 in Kooperation mit der IG Metall - Bezirk Küste]
Creators: name: Kühn, Manuel
name: Ludwig, Thorsten
name: Tholen, Jochen
name: Wolnik, Kevin
Publisher: name: Universität Bremen
Year: 2012
Subjects: subject: Schiffbau
subject: 330

description: Nach den Krisenjahren scheint es, als würde sich die maritime Wirtschaft erholen. Im Jahr 2012 lässt sich für den deutschen Schiffbau eine differenzierte, aber dennoch verbesserte Situation beobachten. Nach langer Zeit kann der deutsche Schiffbau wieder eine positive Beschäftigungsentwicklung vorweisen. In diesem Jahr sind 16.852 Personen auf deutschen Werften beschäftigt und damit liegt eine Steigerung um rund 3,1 Prozent vor. Diese Erhöhung um 501 Mitarbeiter ist erfreulich, wenn man bedenkt, dass von 2008 bis 2011 ein Rückgang um 4.200 Arbeitsplätze zu beobachten war. Innerhalb des vergangenen Jahres hat sich auf diversen Werften einiges ereignet. Wurde einerseits erfolgreich versucht, den Offshore-Markt zu erschließen und Aufträge für hier notwendige Spezialschiffe zu akquirieren, mussten an anderen Stellen Abstriche in der Belegschaft erfolgen und in Einzelfällen sogar Insolvenz beantragt werden. Auffällig ist die Tatsache, dass das vergangene Jahr durch diverse Übernahmen von Werften gekennzeichnet ist. Die Ausbildungssituation hat sich im Vergleich zu den Vorjahren leicht verschlechtert; es kann sowohl eine Minderung der Ausbildungsquote um einen Prozentpunkt als auch ein Minus bei der Zahl der unbefristeten Übernahmen beobachtet werden. Hingegen hat sich die Auftragslage etwas verbessert.
Gesellschaftliche Modernisierung und Regulierung von Arbeit : Abschlussbericht des Projektverbunds “Gesellschaftlicher Wandel und neue Regulierungsmuster von Arbeit”
Creators: name: Dombois, Rainer
name: Holtrup, André
name: Mehlis, Peter
name: Peter, Lothar
name: Reihert, Claudia
name: Spitzley, Helmut
name: Voss, Jenna
name: Warsewa, Günter
Publisher: name: Universität Bremen
Year: 2007
Subjects: subject: Arbeit
subject: 300

description: Globalisierung und Tertiarisierung, aber auch Individualisierung, Enttraditionalisierung und Subjektivierung von Arbeit markieren Prozesse und Entwicklungen, die auch in Deutschland die grundlegenden Rahmenbedingungen der Regulierung von Arbeit verändern und neue Anforderungen an sie generieren. Das Deutsche Modell der Arbeitsbeziehungen mit seinem spezifischen Arrangement von Regulierungsakteuren und -formen steht unter Anpassungsdruck. Dieser Forschungsbericht gibt Auskunft über die Forschungstätigkeiten im Rahmen des am IAW angesiedelten Projektverbundes „Gesellschaftlicher Wandel und neue Regulierungsmuster von Arbeit“. Er referiert die zentralen Ergebnisse aus den vier Teilprojekten und skizziert die Befunde, die sich als allgemeine Tendenzen aus ihnen ableiten lassen. Insgesamt bestätigt die Empirie des Forschungsverbundes, dass Arbeitsansprüche aus der Subjektperspektive an Gewicht gewinnen und dass die betriebliche und teilweise auch die individuelle Ebene bei der Regulierung von Arbeits- und Beschäftigungsbedingungen an Bedeutung zunehmen. Die Befunde lassen aber - anders als vielfach angenommen - auch zukünftig keine durchgreifende und umfassende Individualisierung der Arbeitsbeziehungen erwarten.
Mathematical modelling of passive displacement dual cooling coil (PDDCC) system in a tropical climate
Creators: name: Myat, Aung
name: Yang, Josiah
name: Panisilvam, Jeggathishwaran
name: Soh, Yong Loke
name: An, Hui
name: Wang, Pengcheng
name: Jusuf, Steve Kardinal
Publisher: name: Singapore Institute of Technology
Year: 2023
Subjects: Building science, technologies and systems

description: Unlike the conventional displacement ventilation (DV) systems, the Passive Displacement Dual Cooling Coil (PDDCC) system generates airflow in indoor environments based on natural convection and eliminates the necessity of mechanical ventilation to meet the thermal comfort and indoor air quality requirements. Investigations on such PDDCC systems, though, have been largely limited and its performance capacity and fluid flow behaviour are not fully understood. A mathematical model was, hence, developed in the current study to explore the effects of various boundary conditions on the performance of the PDDCC system. Results obtained from the mathematical model were, first, compared and validated against the measurement readings gathered from an experimental investigation conducted on the PDDCC system in a controlled test environment. The validated mathematical model was then applied to a parametric evaluation where the effects of chilled water supply (CHWS) temperature, flow rate, and return air temperature on the PDDCC system performance were examined. The varying effect of the latent and sensible cooling load was observed at the different boundary conditions applied to the PDDCC model. Slightly more than 32% of rise in total cooling load was predicted by reducing the CHWS temperature which established a much more significant contribution in comparison to the CHWS flow rate which generated approximately 5% rise in the total cooling load. Findings were supported by examining the sensible heat ratio (SHR) and the ratio of Latent cooling load: Sensible cooling load which was then was attributed to the temperature difference between the supply and return air temperature. By ensuring the maximum temperature difference, the total cooling load performance of the PDDCC system can be maximised. The contribution of both the CHWS temperature and flowrate was essential to achieve the maximum cooling load, hence, improving the total cooling performance of the PDDCC as a result.
Kortikale neuronale Netzwerke auf Multielektrodenarrays als reduktionistischer Ansatz zur Aufklärung der Funktionsprinzipien des zerebralen Kortex
Creators: name: Reimer, Tom
Publisher: name: Universität Rostock
Year: 2013
Subjects: subject: 610 Medical sciences Medicine
subject: 570 Life science

description: Kortikale neuronale Netzwerke, kultiviert auf Multielektrodenarrays, dienten als reduktionistischer Ansatz zur Aufklärung der Funktionsprinzipien des zerebralen Kortex. Mittels Struktur-Funktions-Analysen wurde der Zusammenhang zwischen dem Aktivitätsmuster der Spontanaktivität der Netzwerke und ihrer zellulären Zusammensetzung analysiert. Die relativ stabile synchrone Burst-Aktivität wurde parvalbumin-positiven Interneuronen zugeordnet. Sie inhibierte die Spike-Aktivität anderer Neurone. Eine neue Theorie interneuronaler Kommunikation durch schwache elektrische Felder ist dargelegt.
Constraining the Movement of the Spiral Features and the Locations of Planetary Bodies within the AB Aur System
Creators: name: Lomax, Jamie R.
name: Wisniewski, John P.
name: Grady, Carol A.
name: McElwain, Michael W.
name: Hashimoto, Jun
name: Kudo, Tomoyuki
name: Kusakabe, Nobuhiko
name: Okamoto, Yoshiko K.
name: Fukagawa, Misato
name: Abe, Lyu
name: Brandner, Wolfgang
name: Brandt, Timothy D.
name: Carson, Joseph C.
name: Currie, Thayne M.
name: Egner, Sebastian
name: Feldt, Markus
name: Goto, Miwa
name: Guyon, Olivier
name: Hayano, Yutaka
name: Hayashi, Masahiko
name: Hayashi, Saeko S.
name: Henning, Thomas
name: Hodapp, Klaus W.
name: Inoue, Akio
name: Ishii, Miki
name: Iye, Masanori
name: Janson, Markus
name: Kandori, Ryo
name: Knapp, Gillian R.
name: Kuzuhara, Masayuki
name: Kwon, Jungmi
name: Matsuo, Taro
name: Mayama, Satoshi
name: Miyama, Shoken
name: Momose, Munetake
name: Morino, Jun-Ichi
name: Moro-Martin, Amaya
name: Nishimura, Tetsuo
name: Pyo, Tae-Soo
name: Schneider, Glenn H
name: Serabyn, Eugene
name: Sitko, Michael L.
name: Suenaga, Takuya
name: Suto, Hiroshi
name: Suzuki, Ryuji
name: Takahashi, Yasuhiro H.
name: Takami, Michihiro
name: Takato, Naruhisa
name: Terada, Hiroshi
name: Thalmann, Christian
name: Tomono, Daigo
name: Turner, Edwin L.
name: Watanabe, Makoto
name: Yamada, Toru
name: Takami, Hideki
name: Usuda, Tomonori
name: Tamura, Motohide
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We present new analysis of multi-epoch, H-band, scattered light images of the AB Aur system. We used a Monte Carlo, radiative transfer code to simultaneously model the system's SED and H-band polarized intensity imagery. We find that a disk-dominated model, as opposed to one that is envelope dominated, can plausibly reproduce AB Aur's SED and near-IR imagery. This is consistent with previous modeling attempts presented in the literature and supports the idea that at least a subset of AB Aur's spirals originate within the disk. In light of this, we also analyzed the movement of spiral structures in multi-epoch H-band total light and polarized intensity imagery of the disk. We detect no significant rotation or change in spatial location of the spiral structures in these data, which span a 5.8 year baseline. If such structures are caused by disk-planet interactions, the lack of observed rotation constrains the location of the orbit of planetary perturbers to be >47 AU.
description: 8 pages, 3 figures, 1 table, Accepted to ApJ
Revisiting Proxima with ESPRESSO
Creators: name: Suárez Mascareño, Alejandro
Publisher: name: Zenodo
Year: 2020
Subjects: Exoplanets
Proxima
ESPRESSO
Radial velocities

description: The discovery of Proxima b marked one of the most important milestones in exoplanetary science in recent years. Yet the limited precision of the available radial velocity data and the difficulty in modelling the stellar activity calls for a confirmation of the Earth-mass planet.
 We aim to confirm the presence of Proxima b using independent measurements obtained with the new ESPRESSO spectrograph, and refine the planetary parameters taking advantage of its improved precision.
 Methods: We analysed 63 spectroscopic ESPRESSO observations of Proxima (Gl 551) taken during 2019. We obtained radial velocity measurements with a typical radial velocity photon noise of 26 cm s-1. We combined these data with archival spectroscopic observations and newly obtained photometric measurements to model the stellar activity signals and disentangle them from planetary signals in the radial velocity (RV) data. We ran a joint Markov chain Monte Carlo analysis on the time series of the RV and full width half maximum of the cross-correlation function to model the planetary and stellar signals present in the data, applying Gaussian process regression to deal with the stellar activity signals.
 We confirm the presence of Proxima b independently in the ESPRESSO data and in the combined ESPRESSO+ HARPS+UVES dataset. The ESPRESSO data on its own shows Proxima b at a period of 11.218 ± 0.029 days, with a minimum mass of 1.29 ± 0.13 M⊕. In the combined dataset we measure a period of 11.18427 ± 0.00070 days with a minimum mass of 1.173 ± 0.086 M⊕. We get a clear measurement of the stellar rotation period (87 ± 12 d) and its induced RV signal, but no evidence of stellar activity as a potential cause for the 11.2 days signal. We find some evidence for the presence of a second short-period signal, at 5.15 days with a semi-amplitude of only 40 cm s-1. If caused by a planetary companion, it would correspond to a minimum mass of 0.29 ± 0.08 M⊕. We find that forthe case of Proxima, the full width half maximum of the cross-correlation function can be used as a proxy for the brightness changes and that its gradient with time can be used to successfully detrend the RV data from part of the influence of stellar activity. The activity-induced RV signal in the ESPRESSO data shows a trend in amplitude towards redder wavelengths. Velocities measured using the red end of the spectrograph are less affected by activity, suggesting that the stellar activity is spot dominated. This could be used to create differential RVs that are activity dominated and can be used to disentangle activity-induced and planetary-induced signals. The data collected excludes the presence of extra companions with masses above 0.6 M⊕ at periods shorter than 50 days.
description: Seminar at the University of Birmingham
Governance der Politikberatung in der deutschen Rentenpolitik
Creators: name: Sommer, Jörg
name: Wehlau, Diana
Publisher: name: Universität Bremen
Year: 2010
Subjects: subject: Rentenpolitik
subject: 320

description: Das politische System der Bundesrepublik Deutschland hat in den letzten Jahren einen massiven Wandel seiner Regierungs- und Steuerungsfähigkeit erfahren, der im politikwissenschaftlichen Diskurs als neue Form der „Governance“ beschrieben wird. Eine Erscheinungsform des konstatierten Wandels ist die zunehmende Ausdifferenzierung der politischen Akteursvielfalt, die sich auch in der Intensivierung der Politikberatung widerspiegelt. Bezogen auf das Politikfeld Alterssicherung liegen bislang nur vereinzelte Informationen darüber vor, welche Akteure und Organisationen in diesem Bereich Politikberatung betreiben und als Teil der „rentenpolitischen Governance“ charakterisiert werden können. Um das bestehende Informationsdefizit abzubauen, wird auf Basis einer empirischen Erhebung eine Bestandsaufnahme der Beratungslandschaft in der deutschen Rentenpolitik erarbeitet, die Schlussfolgerungen im Hinblick auf die Struktur und die Problemlösungsfähigkeit der rentenpolitischen Governance in Deutschland erlauben.
An exploration of strategic international human resource management for multinational nonprofit enterprises
Creators: name: Merlot., Elizabeth S.
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Von der Meldestelle zum Bürger Service Center Horn-Lehe : Mehr Servicequalität durch innovative Arbeitsorganisation
Creators: name: Heisig, Ulrich
name: Schleibaum, Jörg
Publisher: name: Universität Bremen
Year: 2004
Subjects: subject: Bürgeramt
subject: Verwaltung
subject: 320

description: Mit der vorliegenden Untersuchung rekonstruieren und dokumentieren wir einen längerfristig angelegten Prozess der Transformation von traditionell organisierter Verwaltungsarbeit in einer Meldestelle zu moderner Dienstleistungsarbeit in einem Bürger Service Center. Im Zentrum der Untersuchung stehen die Akteure, die den Reorganisationsprozess vor Ort vorangetrieben und zum Erfolg geführt haben. Hierzu zählen neben dem Amtsleiter und dem regionale Personalrat vor allem die Beschäftigten selbst, die den mit der Einrichtung des Bürger Service Centers Horn-Lehe erhobenen Anspruch auf Bürgerfreundlichkeit und hohe Servicequalität mit ihrer täglichen Arbeit einlösen müssen.
An Erlang Implementation of Multiparty Session Actors
Creators: name: Fowler, Simon
Publisher: name: arXiv
Year: 2016
Subjects: subject: Programming Languages (cs.PL)
subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: By requiring co-ordination to take place using explicit message passing instead of relying on shared memory, actor-based programming languages have been shown to be effective tools for building reliable and fault-tolerant distributed systems. Although naturally communication-centric, communication patterns in actor-based applications remain informally specified, meaning that errors in communication are detected late, if at all. Multiparty session types are a formalism to describe, at a global level, the interactions between multiple communicating entities. This article describes the implementation of a prototype framework for monitoring Erlang/OTP gen_server applications against multiparty session types, showing how previous work on multiparty session actors can be adapted to a purely actor-based language, and how monitor violations and termination of session participants can be reported in line with the Erlang mantra of "let it fail". Finally, the framework is used to implement two case studies: an adaptation of a freely-available DNS server, and a chat server.
description: In Proceedings ICE 2016, arXiv:1608.03131
Revisiting Proxima with ESPRESSO
Creators: name: Suárez Mascareño, Alejandro
Publisher: name: Zenodo
Year: 2020
Subjects: Exoplanets
stars
radial velocity
ESPRESSO
Proxima

description: The discovery of Proxima b marked one of the most important milestones in exoplanetary science in recent years. Yet the limited precision of the available radial velocity data and the difficulty in modelling the stellar activity calls for a confirmation of the Earth-mass planet.
 We aim to confirm the presence of Proxima b using independent measurements obtained with the new ESPRESSO spectrograph, and refine the planetary parameters taking advantage of its improved precision.
 We analysed 63 spectroscopic ESPRESSO observations of Proxima (Gl 551) taken during 2019. We obtained radial velocity measurements with a typical radial velocity photon noise of 26 cm s-1. We combined these data with archival spectroscopic observations and newly obtained photometric measurements to model the stellar activity signals and disentangle them from planetary signals in the radial velocity (RV) data. We ran a joint Markov chain Monte Carlo analysis on the time series of the RV and full width half maximum of the cross-correlation function to model the planetary and stellar signals present in the data, applying Gaussian process regression to deal with the stellar activity signals.
 We confirm the presence of Proxima b independently in the ESPRESSO data and in the combined ESPRESSO+ HARPS+UVES dataset. The ESPRESSO data on its own shows Proxima b at a period of 11.218 ± 0.029 days, with a minimum mass of 1.29 ± 0.13 M⊕. In the combined dataset we measure a period of 11.18427 ± 0.00070 days with a minimum mass of 1.173 ± 0.086 M⊕. We get a clear measurement of the stellar rotation period (87 ± 12 d) and its induced RV signal, but no evidence of stellar activity as a potential cause for the 11.2 days signal. We find some evidence for the presence of a second short-period signal, at 5.15 days with a semi-amplitude of only 40 cm s-1. If caused by a planetary companion, it would correspond to a minimum mass of 0.29 ± 0.08 M⊕. We find that forthe case of Proxima, the full width half maximum of the cross-correlation function can be used as a proxy for the brightness changes and that its gradient with time can be used to successfully detrend the RV data from part of the influence of stellar activity. The activity-induced RV signal in the ESPRESSO data shows a trend in amplitude towards redder wavelengths. Velocities measured using the red end of the spectrograph are less affected by activity, suggesting that the stellar activity is spot dominated. This could be used to create differential RVs that are activity dominated and can be used to disentangle activity-induced and planetary-induced signals. The data collected excludes the presence of extra companions with masses above 0.6 M⊕ at periods shorter than 50 days.
description: Seminar at the CAB-INTA CSIC research centre
ZAP – Muito mais que um acesso privilegiado
Creators: name: Ramos, Sérgio Filipe Carvalho
name: Silva, António
Publisher: name: Neutro à Terra
Year: 2012

description: Parafraseando as prescrições e especificações técnicas da 2ª Edição do Manual de Infraestruturas de Telecomunicações em Edifícios (ITED), “Os fogos de uso residencial possuem, obrigatoriamente, um local onde se concentram as três tecnologias: par de cobre (PC), cabo coaxial (CC) e fibra ótica (FO). Esse local é designado por Zona de Acesso Privilegiado (ZAP) e localiza‐se na divisão mais adequada, no entendimento do projetista e de acordo com as preferências do dono de obra“. Nesta zona concentram‐se as 3 tecnologias atualmente obrigatórias constituindo, assim, um suporte para o fornecimento avançado de serviços tecnológicos evoluídos. A modernização e evolução das infraestruturas de comunicações eletrónicas em Portugal na última década, quer ao nível regulatório, quer ao nível tecnológico dos equipamentos, constituem, implacavelmente, um poderoso incentivo à expansão da sociedade do conhecimento que deixaremos como legado às gerações vindouras.
description: Neutro à Terra, n. 9 (2012): Revista Técnico-Científica (Primeiro Semestre)
The Transformation of European Port Cities - Final Report on the New EPOC Port City Audit
Creators: name: Warsewa, Günter
Publisher: name: Universität Bremen
Year: 2006
Subjects: subject: Hafen
subject: Stadtentwicklung
subject: 910

description: Globalisation, technological developments, increasing competition and climate change are some of the major challenges that currently affect all port-cities regardless of size or location. To answer these challenges, further efforts must be undertaken – particularly to improve the capacities for innovation, to enhance the efficiency of social inclusion and labour market integration and to intensify international relations. Dealing with these tasks, the European port cities have learnt to adjust to the conditions of the 21st century. Today they have become a European laboratory for the modern city in a globalised knowledge society. So at the end of intense discussions and analyses involving 10 European port cities there is a good news story: Despite all problems with industrial decline and economic crisis the European port-cities are emerging as modern maritime cities with strongly performing ports, but also new economic sectors like high tech production, science and research, tourism, culture and other modern services.
title: "Hardness" as a semantic audio descriptor for music using automatic feature extraction
Creators: name: Czedik-Eysenberg, Isabella
name: Knauf, Denis
name: Reuter, Christoph
Publisher: name: Gesellschaft für Informatik, Bonn
Year: 2017
Subjects: subject: Music
subject: Semantic Audio Feature Extraction
subject: Hardness
subject: Heaviness
subject: Metal
subject: High Level Descriptor

description: The quality of "hardness" in music is an attribute that is most commonly associated with genres like metal or hard rock. However, other examples of music raise the question of whether there is a genre-independent general dimension of "hardness" that can be obtained from the signal automatically based on psychoacoustical features. In listening experiments 40 subjects were asked to rate 62 music excerpts according to their hardness. Using MATLAB toolboxes, a set of features covering spectral and temporal sound properties was obtained from the stimuli and investigated in terms of their correlation with the subjective ratings. By means of multiple linear regression analysis a model for musical hardness was constructed which shows a correlation of r = 0.86 with the experimental results. This proposes musical hardness as a useful high level descriptor for analysing collections of music. In ongoing experiments the fitness of this model is being further evaluated.
Estimating gravitational radiation from super-emitting compact binary systems
Creators: name: Hanna, Chad
name: Johnson, Matthew C.
name: Lehner, Luis
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Binary black hole mergers are among the most violent events in the Universe, leading to extreme warping of spacetime and copious emission of gravitational radiation. Even though black holes are the most compact objects they are not necessarily the most efficient emitters of gravitational radiation in binary systems. The final black hole resulting from a binary black hole merger retains a significant fraction of the pre-merger orbital energy and angular momentum. A non-vacuum system can in principle shed more of this energy than a black hole merger of equivalent mass. We study these super-emitters through a toy model that accounts for the possibility that the merger creates a compact object that retains a long-lived time-varying quadrupole moment. This toy model can capture the merger of neutron stars, but it can also be used to consider more exotic compact binaries. We hope that this toy model can serve as a guide to more rigorous numerical investigations into these systems.
description: 10 pages, 5 figures
Saber on ARM
Creators: name: Karmakar, Angshuman
name: Bermudo Mera, Jose Maria
name: Sinha Roy, Sujoy
name: Verbauwhede, Ingrid
Publisher: name: IACR Transactions on Cryptographic Hardware and Embedded Systems
Year: 2018

description: The CCA-secure lattice-based post-quantum key encapsulation scheme Saber is a candidate in the NIST’s post-quantum cryptography standardization process. In this paper, we study the implementation aspects of Saber in resourceconstrained microcontrollers from the ARM Cortex-M series which are very popular for realizing IoT applications. In this work, we carefully optimize various parts of Saber for speed and memory. We exploit digital signal processing instructions and efficient memory access for a fast implementation of polynomial multiplication. We also use memory efficient Karatsuba and just-in-time strategy for generating the public matrix of the module lattice to reduce the memory footprint. We also show that our optimizations can be combined with each other seamlessly to provide various speed-memory trade-offs. Our speed optimized software takes just 1,147K, 1,444K, and 1,543K clock cycles on a Cortex-M4 platform for key generation, encapsulation and decapsulation respectively. Our memory efficient software takes 4,786K, 6,328K, and 7,509K clock cycles on an ultra resource-constrained Cortex-M0 platform for key generation, encapsulation, and decapsulation respectively while consuming only 6.2 KB of memory at most. These results show that lattice-based key encapsulation schemes are perfectly practical for securing IoT devices from quantum computing attacks.
description: IACR Transactions on Cryptographic Hardware and Embedded Systems, Volume 2018, Issue 3
The unseen planets of double belt debris disk systems
Creators: name: Shannon, Andrew
name: Bonsor, Amy
name: Kral, Quentin
name: Matthews, Elisabeth
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The gap between two component debris disks is often taken to be carved by intervening planets scattering away the remnant planetesimals. We employ N-body simulations to determine how the time needed to clear the gap depends on the location of the gap and the mass of the planets. We invert this relation, and provide an equation for the minimum planet mass, and another for the expected number of such planets, that must be present to produce an observed gap for a star of a given age. We show how this can be combined with upper limits on the planetary system from direct imaging non-detections (such as with GPI or SPHERE) to produce approximate knowledge of the planetary system.
description: Accepted to MNRAS
A short-period sub-Earth orbiting Proxima Centauri
Creators: name: Suárez Mascareño, Alejandro
Publisher: name: Zenodo
Year: 2022
Subjects: Exoplanets
Proxima
radial velocity
stellar activity
ESPRESSO

description: The discovery of a planetary candidate orbiting the habitable zone of our closest neighbor, Proxima Centauri (Gl 551), shook the planetary community as few other discoveries have done in recent years. It not only showed that the nearest star to the Sun could host a planetary system but also that, given the right conditions, it could host a habitable rocky planet. 2020 brought back the attention to Proxima with the announcement of a second planetary candidate in the system, the confirmation of Proxima b, using ESPRESSO, and the suggestion of a third, very low mass. Now, after an intense observational campaign, we can confidently say there’s a third companion with just one quarter of the mass of the Earth. Proxima d is one of the lightest exoplanets known to date. It orbits its parent star at 0.029 AU, with a period of 5.12 days. It’s induced RV semi-amplitude, of just 39 cm/s on a V-mag 11 star, highlights the capabilities of the ESPRESSO spectrograph, installed at the VLT telescope array of the Paranal observatory. The signal has an amplitude that is just 1/5 of the amplitude of the activity-induced radial velocity signal, which shows that, under the right conditions, current techniques can detect planetary signals much smaller than activity signals. The discovery of Proxima d opens the door to the characterization of the population of very low mass planets of the solar neighborhood. It shows that radial velocity studies are now capable of detecting exoplanets with masses similar to the Earth and much smaller.
Predicting consumer reactions to innovative products : a test of competing theories
Creators: name: McDonald., Heath
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Bewältigungsstrategien und Rahmenbedingungen von Mitarbeiter*innen in Belastungssituationen in der Arbeit mit „Hoch-Risiko-Klientel“ in der stationären Kinder- und Jugendhilfe
Creators: name: Ramaj, Andrea
name: Jarmer, Mayan
Publisher: name: Hochschule Bremen
Year: 2020
Subjects: subject: Forschungsbericht Qualitative Sozialforschung Praxisforschung und Innovation in der Sozialen Arbeit
subject: Praxisforschung und Innovation in der Sozialen Arbeit
subject: 80

description: Die stationäre Erziehungshilfe weist für hochbelastete Kinder und Jugendliche mit komplexen Problemlagen eine hohe Misserfolgs- und Abbruchrate auf. Diese werden im aktuellen Fachdiskurs oft als „Systemsprenger*innen“ oder „Hoch-Risiko-Klientel bezeichnet. Diese Begriffe sollen nicht stigmatisieren, sondern die Ohnmacht der bisher vorhandenen Hilfesysteme verdeutlichen. (Baumann 2018: 2f.) Aufgrund des fehlenden Angebots für Einzelfälle ist die intensivpädagogische Wohngruppe „PortNord“ entstanden. Das Projekt wird durch vier freie Träger der Bremer Jugendhilfe getragen. Die Mitarbeiter*innen des Pilotprojekts sind aufgrund der Folgen von komplexen Traumatisierungen der Klient*innen einer hohen Belastung ausgesetzt. Sowohl für die Fachkräfte, als auch für die Klient*innen bedarf es eines hohen Schutzes, Verlässlichkeit und Stabilität. Ziel ist es für die Klientel eine Entwicklungsperspektive zu schaffen, um Teilhabe an der Gesellschaft und eine konstruktive Lebensführung zu ermöglichen. Das Projekt wurde über ein Jahr lang erforscht. Dabei entstanden sehr eindrückliche und vielschichtige Analysen, die auf der Grundlage einer qualitativen empirischen Erhebung und deren Analyse wertvolle Hinweise und Empfehlungen für die Praxis geben.
Multi-Threaded Actors
Creators: name: Azadbakht, Keyvan
name: de Boer, Frank S.
name: Serbanescu, Vlad
Publisher: name: arXiv
Year: 2016
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Programming Languages (cs.PL)
subject: FOS: Computer and information sciences

description: In this paper we introduce a new programming model of multi-threaded actors which feature the parallel processing of their messages. In this model an actor consists of a group of active objects which share a message queue. We provide a formal operational semantics, and a description of a Java-based implementation for the basic programming abstractions describing multi-threaded actors. Finally, we evaluate our proposal by means of an example application.
description: In Proceedings ICE 2016, arXiv:1608.03131
Ambiguities in gravitational lens models: the density field from the source position transformation
Creators: name: Unruh, Sandra
name: Schneider, Peter
name: Sluse, Dominique
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Strong gravitational lensing is regarded as the most precise technique to measure the mass in the inner region of galaxies or galaxy clusters. In particular, the mass within one Einstein radius can be determined with an accuracy of order of a few percent or better, depending on the image configuration. For other radii, however, degeneracies exist between galaxy density profiles, precluding an accurate determination of the enclosed mass. The source position transformation (SPT), which includes the well-known mass-sheet transformation (MST) as a special case, describes this degeneracy of the lensing observables in a more general way. In this paper we explore properties of an SPT, removing the MST to leading order, i.e., we consider degeneracies which have not been described before. The deflection field $\boldsymbol{\hatα}(\boldsymbolθ)$ resulting from an SPT is not curl-free in general, and thus not a deflection that can be obtained from a lensing mass distribution. Starting from a variational principle, we construct lensing potentials that give rise to a deflection field $\boldsymbol{\tildeα}$, which differs from $\boldsymbol{\hatα}$ by less than an observationally motivated upper limit. The corresponding mass distributions from these 'valid' SPTs are studied: their radial profiles are modified relative to the original mass distribution in a significant and non-trivial way, and originally axi-symmetric mass distributions can obtain a finite ellipticity. These results indicate a significant effect of the SPT on quantitative analyses of lens systems. We show that the mass inside the Einstein radius of the original mass distribution is conserved by the SPT; hence, as is the case for the MST, the SPT does not affect the mass determination at the Einstein radius. [...]
description: 13 pages, 16 figures, submitted to A&A
A short-period sub-Earth orbiting Proxima Centauri
Creators: name: Suárez Mascareño, Alejandro
name: ESPRESSO Consortium
Publisher: name: Zenodo
Year: 2022
Subjects: Exoplanets
Radial Velocity
Proxima
ESPRESSO

description: The discovery of a planetary candidate orbiting the habitable zone of our closest neighbor, Proxima Centauri (Gl 551), shook the planetary community as few other discoveries have done in recent years. It not only showed that the nearest star to the Sun could host a planetary system but also that, given the right conditions, it could host a habitable rocky planet. 2020 brought back the attention to Proxima with the announcement of a second planetary candidate in the system, the confirmation of Proxima b, using ESPRESSO, and the suggestion of a third, very low mass. Now, after an intense observational campaign, we can confidently say there’s a third companion with just one quarter of the mass of the Earth. Proxima d is one of the lightest exoplanets known to date. It orbits its parent star at 0.029 AU, with a period of 5.12 days. It’s induced RV semi-amplitude, of just 39 cm/s on a V-mag 11 star, highlights the capabilities of the ESPRESSO spectrograph, installed at the VLT telescope array of the Paranal observatory. The signal has an amplitude that is just 1/5 of the amplitude of the activity-induced radial velocity signal, which shows that, under the right conditions, current techniques can detect planetary signals much smaller than activity signals. The discovery of Proxima d opens the door to the characterization of the population of very low mass planets of the solar neighborhood. It shows that radial velocity studies are now capable of detecting exoplanets with masses similar to the Earth and much smaller.
Studentisches Wohnen in Bremen und Bremerhaven
Creators: name: Mossig, Ivo
name: Warsewa, Günter
name: Wolnik, Kevin
name: Fortmann, Fabian
name: Bas, Jessica
Publisher: name: Universität Bremen
Year: 2018
Subjects: subject: Wohnsituation
subject: Studierende
subject: Bremen
subject: Bremerhaven
subject: 300

description: Hintergrund der Untersuchung ist die zunehmend angespannte Lage des städtischen Wohnungsmarktes und die damit verbundene Frage, ob und auf welche Weise die Studierenden im Land Bremen mit ihren Präferenzen und Wohnentscheidungen vor allem in den Segmenten, die Studierenden zugänglich sind, reagieren. Mittels einer repräsentativen Umfrage wurde untersucht, welche Probleme den Studierenden im Land Bremen bei der Wohnungssuche begegnen, welche Wohnformen und Wohnlagen von ihnen bevorzugt werden und wie ihre Wohnentscheidungen mit dem verfügbaren Budget zusammenhängen. Eine generelle Verschiebung bezüglich bevorzugter Wohnformen und Wohnstandorte ist dabei in Bremen trotz erheblich gestiegener Mietausgaben nicht zu erkennen. Auffällig ist aber ein wachsender Anteil von Studierenden, die auf das Wohnen bei Eltern oder Verwandten ausweichen. Aus dem steigenden Druck auf den Wohnungsmarkt ergibt sich ein erkennbarer Handlungsbedarf zur Schaffung studentischen Wohnraums. Reaktionen auf diesen Handlungsbedarf haben einige nach wie vor wirkmächtige Besonderheiten der studentischen Präferenzen und des studentischen Wohnverhaltens zu berücksichtigen.