@book{OPUS4-62240, title = {Lokales Integrationsmanagement in Deutschland, Schweden und Frankreich}, editor = {Bogumil, J{\"o}rg and Kuhlmann, Sabine and Hafner, Jonas and Kastilan, Andr{\´e} and Oehlert, Franziska and Reusch, Marie Catherine}, publisher = {Nomos}, address = {Baden-Baden}, isbn = {978-3-7560-0558-1}, doi = {10.5771/9783748939115}, pages = {331}, year = {2023}, abstract = {Im vorliegenden Band wird das lokale Integrationsmanagement in Deutschland, Frankreich und Schweden vergleichend untersucht. Im Mittelpunkt stehen Verflechtungsstrukturen, Koordination und Leistungsf{\"a}higkeit der Integrationsverwaltung mit besonderem Fokus auf den Entwicklungen nach der Fl{\"u}chtlingskrise von 2015/16. Auf der Grundlage von Fallstudien und Experteninterviews in den drei L{\"a}ndern wird das institutionelle Zusammenspiel von Akteuren im Mehrebenensystem und im lokalen Raum analysiert. Dabei werden jeweils die nationalen Rahmenbedingungen, lokalen Gestaltungsvarianten und krisenbedingten Herausforderungen des Integrationsmanagement kommunen- und l{\"a}ndervergleichend in den Blick genommen. Gest{\"u}tzt auf illustrative Praxisbeispiele und Tiefeneinblicke in die lokalen Handlungsprobleme leitet die Studie Lehren und Empfehlungen f{\"u}r eine Optimierung des Integrationsmanagements und eine krisenresilientere Verwaltungsorganisation in diesem Aufgabenbereich ab.}, language = {de} } @phdthesis{Quinzan2023, author = {Quinzan, Francesco}, title = {Combinatorial problems and scalability in artificial intelligence}, doi = {10.25932/publishup-61111}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-611114}, school = {Universit{\"a}t Potsdam}, pages = {xi, 141}, year = {2023}, abstract = {Modern datasets often exhibit diverse, feature-rich, unstructured data, and they are massive in size. This is the case of social networks, human genome, and e-commerce databases. As Artificial Intelligence (AI) systems are increasingly used to detect pattern in data and predict future outcome, there are growing concerns on their ability to process large amounts of data. Motivated by these concerns, we study the problem of designing AI systems that are scalable to very large and heterogeneous data-sets. Many AI systems require to solve combinatorial optimization problems in their course of action. These optimization problems are typically NP-hard, and they may exhibit additional side constraints. However, the underlying objective functions often exhibit additional properties. These properties can be exploited to design suitable optimization algorithms. One of these properties is the well-studied notion of submodularity, which captures diminishing returns. Submodularity is often found in real-world applications. Furthermore, many relevant applications exhibit generalizations of this property. In this thesis, we propose new scalable optimization algorithms for combinatorial problems with diminishing returns. Specifically, we focus on three problems, the Maximum Entropy Sampling problem, Video Summarization, and Feature Selection. For each problem, we propose new algorithms that work at scale. These algorithms are based on a variety of techniques, such as forward step-wise selection and adaptive sampling. Our proposed algorithms yield strong approximation guarantees, and the perform well experimentally. We first study the Maximum Entropy Sampling problem. This problem consists of selecting a subset of random variables from a larger set, that maximize the entropy. By using diminishing return properties, we develop a simple forward step-wise selection optimization algorithm for this problem. Then, we study the problem of selecting a subset of frames, that represent a given video. Again, this problem corresponds to a submodular maximization problem. We provide a new adaptive sampling algorithm for this problem, suitable to handle the complex side constraints imposed by the application. We conclude by studying Feature Selection. In this case, the underlying objective functions generalize the notion of submodularity. We provide a new adaptive sequencing algorithm for this problem, based on the Orthogonal Matching Pursuit paradigm. Overall, we study practically relevant combinatorial problems, and we propose new algorithms to solve them. We demonstrate that these algorithms are suitable to handle massive datasets. However, our analysis is not problem-specific, and our results can be applied to other domains, if diminishing return properties hold. We hope that the flexibility of our framework inspires further research into scalability in AI.}, language = {en} } @article{KaramzadehToularoudHeimannDahmetal.2020, author = {Karamzadeh Toularoud, Nasim and Heimann, Sebastian and Dahm, Torsten and Kr{\"u}ger, Frank}, title = {Earthquake source arrays}, series = {Geophysical journal international}, volume = {221}, journal = {Geophysical journal international}, number = {1}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0956-540X}, doi = {10.1093/gji/ggaa002}, pages = {352 -- 370}, year = {2020}, abstract = {A collection of earthquake sources recorded at a single station, under specific conditions, are considered as a source array (SA), that is interpreted as if earthquake sources originate at the station location and are recorded at the source location. Then, array processing methods, that is array beamforming, are applicable to analyse the recorded signals. A possible application is to use source array multiple event techniques to locate and characterize near-source scatterers and structural interfaces. In this work the aim is to facilitate the use of earthquake source arrays by presenting an automatic search algorithm to configure the source array elements. We developed a procedure to search for an optimal source array element distribution given an earthquake catalogue including accurate origin time and hypocentre locations. The objective function of the optimization process can be flexibly defined for each application to ensure the prerequisites (criteria) of making a source array. We formulated four quantitative criteria as subfunctions and used the weighted sum technique to combine them in one single scalar function. The criteria are: (1) to control the accuracy of the slowness vector estimation using the time domain beamforming method, (2) to measure the waveform coherency of the array elements, (3) to select events with lower location error and (4) to select traces with high energy of specific phases, that is, sp- or ps-phases. The proposed procedure is verified using synthetic data as well as real examples for the Vogtland region in Northwest Bohemia. We discussed the possible application of the optimized source arrays to identify the location of scatterers in the velocity model by presenting a synthetic test and an example using real waveforms.}, language = {en} } @article{BabalolaOmorogieBabarindeetal.2016, author = {Babalola, Jonathan Oyebamiji and Omorogie, Martins Osaigbovo and Babarinde, Adesola Abiola and Unuabonah, Emmanuel Iyayi and Oninla, Vincent Olukayode}, title = {OPTIMIZATION OF THE BIOSORPTION OF Cr3+, Cd2+ AND Pb2+ USING A NEW BIOWASTE: Zea mays SEED CHAFF}, series = {Environmental engineering and management journal}, volume = {15}, journal = {Environmental engineering and management journal}, publisher = {Gh. Asachi Universitatea Tehnic{\"A}ƒ Ia{\AA}Ÿi}, address = {Iasi}, issn = {1582-9596}, pages = {1571 -- 1580}, year = {2016}, abstract = {This study highlights the potential use of yellow Zea mays seed chaff (YZMSC) biomass as a biosorbent for the removal of Cr3+, Cd2+ and Pb2+ ions from aqueous solutions. Fourier transformed Infrared analysis of the biomass suggests that YZMSC biomass is basically composed of cellulose and methyl cellulose. The biosorption capacities, q(max), of YZMSC biomass for Cr3+, Cd2+ and Pb2+ are 14.68, 121.95 and 384.62 mg/g respectively. Biosorption equilibrium was achieved at 20, 30 and 60 min for Cr3+, Cd2+ and Pb2+ respectively. YZMSC biomass was found to have higher biosorption capacity and overall kinetic rate of uptake for Pb2+ than for Cd2+ and Cr3+. However, Cr3+ had better initial kinetic rate of uptake by the biomass than Pb2+ and Cd2+. The Freundlich equilibrium isotherm model was found to describe equilibrium data better than Langmuir model suggesting that biosorption of these metal ions could be on more than one active site on the surface of YZMSC biomass. Kinetic study predicted the pseudo-second kinetic model as being able to better describe kinetic data obtained than either modified pseudo-first order or Bangham kinetic models. Biosorption of Cr3+, Cd2+ and Pb2+ onto YZMSC biomass was endothermic in nature with large positive entropy values. Biosorption of these metal ions onto YZMSC biomass was observed to be feasible and spontaneous above 283 K. Optimization of biomass weight for the removal of these metal ions suggest that 384 kg, 129 kg and 144 kg of YZMSC biomass is required for the removal of 95\% of Cr3+, Cd2+ and Pb2+ metal ions respectively from 100 mg/L of metal ions in 10 tonnes of aqueous solutions.}, language = {en} } @phdthesis{Hoellerer2016, author = {H{\"o}llerer, Reinhard}, title = {Modellierung und Optimierung von B{\"u}rgerdiensten am Beispiel der Stadt Landshut}, doi = {10.25932/publishup-42598}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-425986}, school = {Universit{\"a}t Potsdam}, pages = {xii, 244}, year = {2016}, abstract = {Die Projektierung und Abwicklung sowie die statische und dynamische Analyse von Gesch{\"a}ftsprozessen im Bereich des Verwaltens und Regierens auf kommunaler, L{\"a}nder- wie auch Bundesebene mit Hilfe von Informations- und Kommunikationstechniken besch{\"a}ftigen Politiker und Strategen f{\"u}r Informationstechnologie ebenso wie die {\"O}ffentlichkeit seit Langem. Der hieraus entstandene Begriff E-Government wurde in der Folge aus den unterschiedlichsten technischen, politischen und semantischen Blickrichtungen beleuchtet. Die vorliegende Arbeit konzentriert sich dabei auf zwei Schwerpunktthemen: • Das erste Schwerpunktthema behandelt den Entwurf eines hierarchischen Architekturmodells, f{\"u}r welches sieben hierarchische Schichten identifiziert werden k{\"o}nnen. Diese erscheinen notwendig, aber auch hinreichend, um den allgemeinen Fall zu beschreiben. Den Hintergrund hierf{\"u}r liefert die langj{\"a}hrige Prozess- und Verwaltungserfahrung als Leiter der EDV-Abteilung der Stadtverwaltung Landshut, eine kreisfreie Stadt mit rund 69.000 Einwohnern im Nordosten von M{\"u}nchen. Sie steht als Repr{\"a}sentant f{\"u}r viele Verwaltungsvorg{\"a}nge in der Bundesrepublik Deutschland und ist dennoch als Analyseobjekt in der Gesamtkomplexit{\"a}t und Prozessquantit{\"a}t {\"u}berschaubar. Somit k{\"o}nnen aus der Analyse s{\"a}mtlicher Kernabl{\"a}ufe statische und dynamische Strukturen extrahiert und abstrakt modelliert werden. Die Schwerpunkte liegen in der Darstellung der vorhandenen Bedienabl{\"a}ufe in einer Kommune. Die Transformation der Bedienanforderung in einem hierarchischen System, die Darstellung der Kontroll- und der Operationszust{\"a}nde in allen Schichten wie auch die Strategie der Fehlererkennung und Fehlerbehebung schaffen eine transparente Basis f{\"u}r umfassende Restrukturierungen und Optimierungen. F{\"u}r die Modellierung wurde FMC-eCS eingesetzt, eine am Hasso-Plattner-Institut f{\"u}r Softwaresystemtechnik GmbH (HPI) im Fachgebiet Kommunikationssysteme entwickelte Methodik zur Modellierung zustandsdiskreter Systeme unter Ber{\"u}cksichtigung m{\"o}glicher Inkonsistenzen (Betreuer: Prof. Dr.-Ing. Werner Zorn [ZW07a, ZW07b]). • Das zweite Schwerpunktthema widmet sich der quantitativen Modellierung und Optimierung von E-Government-Bediensystemen, welche am Beispiel des B{\"u}rgerb{\"u}ros der Stadt Landshut im Zeitraum 2008 bis 2015 durchgef{\"u}hrt wurden. Dies erfolgt auf Basis einer kontinuierlichen Betriebsdatenerfassung mit aufwendiger Vorverarbeitung zur Extrahierung mathematisch beschreibbarer Wahrscheinlichkeitsverteilungen. Der hieraus entwickelte Dienstplan wurde hinsichtlich der erzielbaren Optimierungen im dauerhaften Echteinsatz verifiziert. [ZW07a] Zorn, Werner: «FMC-QE A New Approach in Quantitative Modeling», Vortrag anl{\"a}sslich: MSV'07- The 2007 International Conference on Modeling, Simulation and Visualization Methods WorldComp2007, Las Vegas, 28.6.2007. [ZW07b] Zorn, Werner: «FMC-QE, A New Approach in Quantitative Modeling», Ver{\"o}ffentlichung, Hasso-Plattner-Institut f{\"u}r Softwaresystemtechnik an der Universit{\"a}t Potsdam, 28.6.2007.}, language = {de} } @article{KaeserBascheraKohnetal.2013, author = {K{\"a}ser, Tanja and Baschera, Gian-Marco and Kohn, Juliane and Kucian, Karin and Richtmann, Verena and Grond, Ursina and Gross, Markus and von Aster, Michael G.}, title = {Design and evaluation of the computer-based training program Calcularis for enhancing numerical cognition}, series = {Frontiers in psychology}, volume = {4}, journal = {Frontiers in psychology}, number = {31}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2013.00489}, pages = {13}, year = {2013}, abstract = {This article presents the design and a first pilot evaluation of the computer-based training program Calcularis for children with developmental dyscalculia (DD) or difficulties in learning mathematics. The program has been designed according to insights on the typical and atypical development of mathematical abilities. The learning process is supported through multimodal cues, which encode different properties of numbers. To offer optimal learning conditions, a user model completes the program and allows flexible adaptation to a child's individual learning and knowledge profile. Thirty-two children with difficulties in learning mathematics completed the 6-12-weeks computer training. The children played the game for 20 min per day for 5 days a week. The training effects were evaluated using neuropsychological tests. Generally, children benefited significantly from the training regarding number representation and arithmetic operations. Furthermore, children liked to play with the program and reported that the training improved their mathematical abilities.}, language = {en} }