@inproceedings{SurajbaliGraceCoulson2010, author = {Surajbali, Bholanathsingh and Grace, Paul and Coulson, Geoff}, title = {Preserving dynamic reconfiguration consistency in aspect oriented middleware}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41379}, year = {2010}, abstract = {Aspect-oriented middleware is a promising technology for the realisation of dynamic reconfiguration in heterogeneous distributed systems. However, like other dynamic reconfiguration approaches, AO-middleware-based reconfiguration requires that the consistency of the system is maintained across reconfigurations. AO-middleware-based reconfiguration is an ongoing research topic and several consistency approaches have been proposed. However, most of these approaches tend to be targeted at specific contexts, whereas for distributed systems it is crucial to cover a wide range of operating conditions. In this paper we propose an approach that offers distributed, dynamic reconfiguration in a consistent manner, and features a flexible framework-based consistency management approach to cover a wide range of operating conditions. We evaluate our approach by investigating the configurability and transparency of our approach and also quantify the performance overheads of the associated consistency mechanisms.}, language = {en} } @misc{AlHalbouniHolohanTaherietal.2018, author = {Al-Halbouni, Djamil and Holohan, Eoghan P. and Taheri, Abbas and Sch{\"o}pfer, Martin P. J. and Emam, Sacha and Dahm, Torsten}, title = {Geomechanical modelling of sinkhole development using distinct elements}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1061}, issn = {1866-8372}, doi = {10.25932/publishup-46843}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-468435}, pages = {35}, year = {2018}, abstract = {Mechanical and/or chemical removal of material from the subsurface may generate large subsurface cavities, the destabilisation of which can lead to ground collapse and the formation of sinkholes. Numerical simulation of the interaction of cavity growth, host material deformation and overburden collapse is desirable to better understand the sinkhole hazard but is a challenging task due to the involved high strains and material discontinuities. Here, we present 2-D distinct element method numerical simulations of cavity growth and sinkhole development. Firstly, we simulate cavity formation by quasi-static, stepwise removal of material in a single growing zone of an arbitrary geometry and depth. We benchmark this approach against analytical and boundary element method models of a deep void space in a linear elastic material. Secondly, we explore the effects of properties of different uniform materials on cavity stability and sinkhole development. We perform simulated biaxial tests to calibrate macroscopic geotechnical parameters of three model materials representative of those in which sinkholes develop at the Dead Sea shoreline: mud, alluvium and salt. We show that weak materials do not support large cavities, leading to gradual sagging or suffusion-style subsidence. Strong materials support quasi-stable to stable cavities, the overburdens of which may fail suddenly in a caprock or bedrock collapse style. Thirdly, we examine the consequences of layered arrangements of weak and strong materials. We find that these are more susceptible to sinkhole collapse than uniform materials not only due to a lower integrated strength of the overburden but also due to an inhibition of stabilising stress arching. Finally, we compare our model sinkhole geometries to observations at the Ghor Al-Haditha sinkhole site in Jordan. Sinkhole depth ∕ diameter ratios of 0.15 in mud, 0.37 in alluvium and 0.33 in salt are reproduced successfully in the calibrated model materials. The model results suggest that the observed distribution of sinkhole depth ∕ diameter values in each material type may partly reflect sinkhole growth trends.}, language = {en} } @article{KnothKiyMuelleretal.2020, author = {Knoth, Alexander Henning and Kiy, Alexander and M{\"u}ller, Ina and Klein, Mathias}, title = {Competences in context}, series = {Technology, knowledge and learning}, volume = {25}, journal = {Technology, knowledge and learning}, number = {4}, publisher = {Springer}, address = {Dordrecht}, issn = {2211-1662}, doi = {10.1007/s10758-019-09407-8}, pages = {707 -- 731}, year = {2020}, abstract = {Mobile applications are suitable as a structural possibility for students beginning their studies. Using the appReflect.UP,students are encouraged to reflect on the organization, contents, and objectives of their studies. This article focuses on how students can acquire the academic ability to consider their own actions, which is an intrinsic component of academic professionalization. The work examines how a competency framework is derived through study regulations and module descriptions, and how subsequent questions for students' reflection are systematically created using this framework. Next, the hybrid mobile applicationReflect.UPand its underlying software components are introduced, stimulating students' reflections on study content and objectives. The data gathered through the practical use ofReflect.UPis evaluated, and then the ensuing conclusions drawn from students' problems and learning processes for organizing the course of studies are explored. In addition, this paper reflects on the strengths and weaknesses of a mobile application as a sociological and technological compound for structural support of the introductory phase of education.}, language = {en} } @article{WulffBuschhueterWestphaletal.2020, author = {Wulff, Peter and Buschh{\"u}ter, David and Westphal, Andrea and Nowak, Anna and Becker, Lisa and Robalino, Hugo and Stede, Manfred and Borowski, Andreas}, title = {Computer-based classification of preservice physics teachers' written reflections}, series = {Journal of science education and technology}, volume = {30}, journal = {Journal of science education and technology}, number = {1}, publisher = {Springer}, address = {Dordrecht}, issn = {1059-0145}, doi = {10.1007/s10956-020-09865-1}, pages = {1 -- 15}, year = {2020}, abstract = {Reflecting in written form on one's teaching enactments has been considered a facilitator for teachers' professional growth in university-based preservice teacher education. Writing a structured reflection can be facilitated through external feedback. However, researchers noted that feedback in preservice teacher education often relies on holistic, rather than more content-based, analytic feedback because educators oftentimes lack resources (e.g., time) to provide more analytic feedback. To overcome this impediment to feedback for written reflection, advances in computer technology can be of use. Hence, this study sought to utilize techniques of natural language processing and machine learning to train a computer-based classifier that classifies preservice physics teachers' written reflections on their teaching enactments in a German university teacher education program. To do so, a reflection model was adapted to physics education. It was then tested to what extent the computer-based classifier could accurately classify the elements of the reflection model in segments of preservice physics teachers' written reflections. Multinomial logistic regression using word count as a predictor was found to yield acceptable average human-computer agreement (F1-score on held-out test dataset of 0.56) so that it might fuel further development towards an automated feedback tool that supplements existing holistic feedback for written reflections with data-based, analytic feedback.}, language = {en} } @article{KagerJurczokBollietal.2022, author = {Kager, Klara and Jurczok, Anne and Bolli, Swantje and Vock, Miriam}, title = {We were thinking too much like adults}, series = {Teaching and teacher education : an international journal of research and studies}, volume = {113}, journal = {Teaching and teacher education : an international journal of research and studies}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0742-051X}, doi = {10.1016/j.tate.2022.103683}, pages = {13}, year = {2022}, abstract = {This mixed-method study addresses the need for a clear conceptualization of the professional reflection element of Lesson Study (LS), a popular collaborative approach to the professional development of teachers. Grounding and re-framing LS's post-lesson discussion in a theoretical framework of critical and collaborative reflection, we analyze the transcripts of four LS groups at German primary schools, focusing on depth of reflection and teachers' trajectories through their reflective practice. The findings show that LS groups differed significantly in the depth and the trajectories of their reflection processes. We consider implications for post-lesson discussions and critical reflection as a LS core skill.}, language = {en} } @phdthesis{Kager2023, author = {Kager, Klara}, title = {Critical Research Needs in Lesson Study: Then, Now, and Looking Forward}, doi = {10.25932/publishup-60271}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-602711}, school = {Universit{\"a}t Potsdam}, pages = {iii, 252}, year = {2023}, abstract = {The collaboration-based professional development approach Lesson Study (LS), which has its roots in the Japanese education system, has gained international recognition over the past three decades and spread quickly throughout the world. LS is a collaborative method to professional development (PD) that incorporates multiple characteristics that have been identified in the research literature as key to effective PD. Specifically, LS is a long-term process that consists of subsequent inquiry cycles, it is site-based and integrated in teachers' practice, it encourages collaboration and reflection, places a strong emphasis on student learning, and it typically involves external experts that support the process or offer additional insights. As LS integrates all these characteristics, it has rapidly gained international popularity since the turn of the 21st century and is currently being practiced in over 40 countries around the world. This international borrowing of the idea of LS to new national contexts has given rise to a research field that aims to investigate the effectiveness of LS on teacher learning as well as the circumstances and mechanisms that make LS effective in various settings around the world. Such research is important, as borrowing educational innovations and adapting them to new contexts can be a challenging process. Educational innovations that fail to deliver the expected outcomes tend to be abandoned prematurely and before they have been completely understood or a substantial research base has been established. In order to prevent LS from early abandonment, Lewis and colleagues outlined three critical research needs in 2006, not long after LS was initially introduced to the United States. These research needs included (1) developing a descriptive knowledge base on LS, (2) examining the mechanisms by which teachers learn through LS, and (3) using design-based research cycles to analyze and improve LS. This dissertation set out to take stock of the progress that has been made on these research needs over the past 20 years. The scoping review conducted for the framework of this dissertation indicates that, while a large and international knowledge base has been developed, the field has not yet produced reliable evidence of the effectiveness of LS. Based on the scoping review, this dissertation makes the case that Lewis et al.'s (2006) critical research needs should be updated. In order to do so, a number of limitations to the current knowledge base on LS need to be addressed. These limitations include (1) the frequent lack of comparable and replicable descriptions of the LS intervention in publications, (2) the incoherent use or lack of use of theoretical frameworks to explain teacher learning through LS, (3) the inconsistent use of terminology and concepts, and (4) the lack of scientific rigor in research studies and of established ways or tools to measure the effectiveness of LS. This dissertation aims to advance the critical research needs in the field by examining the extent and nature of these limitations in three research studies. The focus of these studies lies on the LS stages of observation and reflection, as these stages have a high potential to facilitate teacher learning. The first study uses a mixed-method design to examine how teachers at German primary schools reflect critically together. The study derives a theory-based definition of critical and collaborative reflection in order to re-frame the reflection element in LS. The second study, a systematic review of 129 articles on LS, assess how transparent research articles are in reporting how teachers observed and reflected together. In addition, it is investigated whether these articles provide any kind of theorization for the stages of observation and reflection. The third study proposes a conceptual model for the field of LS that is based on existing models of continuous professional development and research findings on team effectiveness and collaboration. The model describes the dimensions of input, mediating mechanisms, and outcomes in order to provide a conceptual grid to teachers' continuous professional development through LS.}, language = {en} } @phdthesis{Gulsen2023, author = {Gulsen, Ali}, title = {Empowering leadership, follower reflection, and leader well-being}, doi = {10.25932/publishup-58256}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-582562}, school = {Universit{\"a}t Potsdam}, pages = {196}, year = {2023}, abstract = {This research focuses on empowering leadership, a leadership style that shares autonomy and responsibilities with the followers. Empowering leadership enhances the meaningfulness of work by fostering participation in decision-making, expressing confidence in high performance, and providing autonomy in target setting (Cheong, 2016). I examine how empowering leadership affects followers' reflection. I used data from 528 individuals across 172 teams and found a positive relationship between empowering leadership and followers' reflection. Followers' reflection, in turn, is negatively associated with followers' withdrawal, which mediates the beneficial effect of empowering leadership on leaders' emotional exhaustion. As for the leaders, I propose that empowering leadership is negatively related also to leaders' emotional exhaustion. This research broadens our understanding of empowering leadership's effects on both followers and leaders. Moreover, it integrates empowering leadership, leader emotional exhaustion, and burnout literature. Overall, empowering leadership strengthens members' reflective attitudes and behaviors, which result in reduced withdrawal (and increased presence and contribution) in teams. Because the members contribute to team effort more, the leaders experience less emotional exhaustion. Hence, my work not only identifies new ways through which empowering leadership positively affects followers but also shows how these positive effects on followers benefit the leaders' well-being.}, language = {en} }