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See detailCoSFB – Design and Application of a New Generation of Slim-Floor Construction
Braun, Mathias; Obiala, Renata UL; Odenbreit, Christoph UL et al

in 7th European Conference on Steel and Composite Structures (Eurosteel) (2014)

Detailed reference viewed: 239 (14 UL)
See detailCosmopolitanism, making the nation and the citizen as a salvation theme of turn of the twentieth century pedagogy
Popkewitz, Thomas S. UL

in Tolonen, Tarja; Palmu, Tarja; Lappainen, Sirpa (Eds.) et al Cultural practices and transitions in education (2012)

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See detailCospan DPO Approach: An Alternative for DPO Graph Transformations
Ehrig, Hartmut; Hermann, Frank UL; Prange, Ulrike

in Bulletin of the EATCS (2009)

The DPO approach for graph transformations is based on productions and direct transformations defined by two pushouts, where, roughly spoken, in the first pushout all items in L without K are deleted and ... [more ▼]

The DPO approach for graph transformations is based on productions and direct transformations defined by two pushouts, where, roughly spoken, in the first pushout all items in L without K are deleted and in the second one all items R without K are added, while those items in K are preserved. Intuitively, K is the intersection of L and R and, formally, p is a span of graph morphisms. In this paper we consider productions which are cospans of graph morphisms, and K corresponds to the union of L and R. As before, direct transformations are defined by double pushouts, but now the first pushout adds all items in KnL and the second one deletes KnR. This basic idea can be extended to an alternative graph transformation approach, called cospan DPO approach. Key notions of the classical DPO approach can be reformulated in the cospan DPO approach and our main result shows in which way corresponding concepts and results are equivalent. [less ▲]

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See detailCOSPAR Recommendations in a New Context? Environmental Aspects of Space Mining
Hofmann, Mahulena UL

in Blount, Percy; Masson-Zwaan, Tanja; Moro-Aguilar, Rafael (Eds.) et al Proceedings of the International Institute of Space Law 2016 (2017)

Projects related to space mining open numerous questions, including the guarantees of environmental standards of space activities. this contribution analyses the scope of the competences of COSPAR, the ... [more ▼]

Projects related to space mining open numerous questions, including the guarantees of environmental standards of space activities. this contribution analyses the scope of the competences of COSPAR, the legal character of its recommendations, and their applicability to space mining. [less ▲]

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See detailCost analysis of Smart Lighting Solutions for Smart Cities
Cacciatore, Giuseppe; Fiandrino, Claudio UL; Kliazovich, Dzmitry UL et al

in IEEE International Conference on Communications (ICC), Paris, France, 2017 (2017, May)

Lighting is an essential community service, but current implementations are not energy efficient and impact on the energy budget of the municipalities for at least 40\%. In this paper, we propose ... [more ▼]

Lighting is an essential community service, but current implementations are not energy efficient and impact on the energy budget of the municipalities for at least 40\%. In this paper, we propose heuristics and devise a comparison methodology for new smart lighting solutions in next generation smart cities. The proposed smart lighting techniques make use of Internet of Things (IoT) augmented lamppost, which save energy by turning off or dimming the light according to the presence of citizens. Assessing costs and benefits in adopting the new smart lighting solutions is a pillar step for municipalities to foster real implementation. For evaluation purposes, we have developed a custom simulator which enables the deployment of lampposts in realistic urban environments. The citizens travel on foot along the streets and trigger activation of the lampposts according to the proposed heuristics. For the city of Luxembourg, the results highlight that replacing all existing lamps with LEDs and dimming light intensity according to the presence of users nearby the lampposts is convenient and provides an economical return already after the first year of deployment. [less ▲]

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See detailA cost effective non-commercial ECL-solution for Western blot detections yielding strong signals and low background
Haan, Claude UL; Behrmann, Iris UL

in Journal of Immunological Methods (2007), 318(1-2), 11-9

We compared several alternative ECL solutions for Western blot detection of endogenous proteins in whole cell lysates using inexpensive, commercially available reagents. Starting from an existing protocol ... [more ▼]

We compared several alternative ECL solutions for Western blot detection of endogenous proteins in whole cell lysates using inexpensive, commercially available reagents. Starting from an existing protocol based on p-coumaric acid (pCA) as enhancer, we found that the ECL solution containing 4-iodophenylboronic acid (4IPBA) generated strong specific signals and low background chemiluminescence. We optimised the luminol, 4IPBA and hydrogenperoxide concentrations of this 4IPBA-ECL solution. The optimised 4IPBA-ECL solution (100 mM Tris/HCl pH 8.8, 1.25 mM luminol, 2 mM 4IPBA, 5.3 mM hydrogenperoxide) shows a greatly increased signal intensity compared to the initial pCA-ECL protocol and to some commercially available ECL solutions. In addition, the optimised 4IPBA-ECL solution also generates much lower background chemiluminescence than other non-commercial ECL solutions using p-coumaric acid or 4-iodophenol as enhancers. The 4IPBA-ECL solution was stable when stored but had the lowest background when prepared freshly from stock solutions. Thus, we present an optimised protocol for a well-performing inexpensive ECL solution which is an alternative to expensive commercial ECL solutions and which achieves a better signal and lower background than the commercial solutions tested. [less ▲]

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See detailThe Cost of Environmental Constraints in Traffic Networks: Assessing the Loss of Optimality
Lin, Xin; Tampere, Chris MJ; Viti, Francesco UL et al

in Networks & Spatial Economics (2016)

Increasing numbers of hard environmental constraints are being imposed in urban traffic networks by authorities in an attempt to mitigate pollution caused by traffic. However, it is not trivial for ... [more ▼]

Increasing numbers of hard environmental constraints are being imposed in urban traffic networks by authorities in an attempt to mitigate pollution caused by traffic. However, it is not trivial for authorities to assess the cost of imposing such hard environmental constraints. This leads to difficulties when setting the constraining values as well as implementing effective control measures. For that reason, quantifying the cost of imposing hard environmental constraints for a certain network becomes crucial. This paper first indicates that for a given network, such cost is not only related to the attribution of environmental constraints but also related to the considered control measures. Next, we present an assessment criterion that quantifies the loss of optimality under the control measures considered by introducing the environmental constraints. The criterion can be acquired by solving a bi-level programming problem with/without environmental constraints. A simple case study shows its practicability as well as the differences between this framework and other frameworks integrating the environmental aspects. This proposed framework is widely applicable when assessing the interaction of traffic and its environmental aspects [less ▲]

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See detailCost Sensitive Credit Card Fraud Detection using Bayes Minimum Risk
Correa Bahnsen, Alejandro UL; Stojanovic, Aleksandar UL; Aouada, Djamila UL et al

in 12th International Conference on Machine Learning and Applications (2013)

Credit card fraud is a growing problem that affects card holders around the world. Fraud detection has been an interesting topic in machine learning. Nevertheless, current state of the art credit card ... [more ▼]

Credit card fraud is a growing problem that affects card holders around the world. Fraud detection has been an interesting topic in machine learning. Nevertheless, current state of the art credit card fraud detection algorithms miss to include the real costs of credit card fraud as a measure to evaluate algorithms. In this paper a new comparison measure that realistically represents the monetary gains and losses due to fraud detection is proposed. Moreover, using the proposed cost measure a cost sensitive method based on Bayes minimum risk is presented. This method is compared with state of the art algorithms and shows improvements up to 23% measured by cost. The results of this paper are based on real life transactional data provided by a large European card processing company. [less ▲]

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See detailCost sensitive credit card fraud detection using Bayes minimum risk
Correa Bahnsen, Alejandro UL; Stojanovic, A.; Aouada, Djamila UL et al

in International Conference on Machine Learning and Applications, 2013 IEEE 12th (2013)

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See detailCost sensitive credit card fraud detection using bayes minimum risk
Bahnsen, A. C.; Stojanovic, Aleksandar UL; Aouada, D. et al

in Proceedings - 2013 12th International Conference on Machine Learning and Applications, ICMLA 2013 (2013), 1

Credit card fraud is a growing problem that affects card holders around the world. Fraud detection has been an interesting topic in machine learning. Nevertheless, current state of the art credit card ... [more ▼]

Credit card fraud is a growing problem that affects card holders around the world. Fraud detection has been an interesting topic in machine learning. Nevertheless, current state of the art credit card fraud detection algorithms miss to include the real costs of credit card fraud as a measure to evaluate algorithms. In this paper a new comparison measure that realistically represents the monetary gains and losses due to fraud detection is proposed. Moreover, using the proposed cost measure a cost sensitive method based on Bayes minimum risk is presented. This method is compared with state of the art algorithms and shows improvements up to 23% measured by cost. The results of this paper are based on real life transactional data provided by a large European card processing company. © 2013 IEEE. [less ▲]

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See detailThe COST-Action on cyber bullying: Developing an International Network
Steffgen, Georges UL; Smith, Peter K.

Scientific Conference (2013, July)

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See detailA cost-effective atomic force microscope for undergraduate control laboratories
Jones, C. N.; Goncalves, Jorge UL

in IEEE Transactions on Education (2010), 53(2), 328-334

This paper presents a simple, cost-effective and robust atomic force microscope (AFM), which has been purposely designed and built for use as a teaching aid in undergraduate controls labs. The guiding ... [more ▼]

This paper presents a simple, cost-effective and robust atomic force microscope (AFM), which has been purposely designed and built for use as a teaching aid in undergraduate controls labs. The guiding design principle is to have all components be open and visible to the students, so the inner functioning of the microscope has been made clear to see. All of the parts but one are off the shelf, and assembly time is generally less than two days, which makes the microscope a robust instrument that is readily handled by the students with little chance of damage. While the scanning resolution is nowhere near that of a commercial instrument, it is more than sufficient to take interesting scans of micrometer-scale objects. A survey of students after their having used the AFM resulted in a generally good response, with 80% agreeing that they had a positive learning experience. [less ▲]

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See detailA Cost-Effective Distributed Framework for Data Collection in Cloud-based Mobile Crowd Sensing Architectures
Capponi, Andrea UL; Fiandrino, Claudio UL; Kliazovich, Dzmitry UL et al

in IEEE Transactions on Sustainable Computing (2017)

Mobile crowd sensing received significant attention in the recent years and has become a popular paradigm for sensing. It operates relying on the rich set of built-in sensors equipped in mobile devices ... [more ▼]

Mobile crowd sensing received significant attention in the recent years and has become a popular paradigm for sensing. It operates relying on the rich set of built-in sensors equipped in mobile devices, such as smartphones, tablets and wearable devices. To be effective, mobile crowd sensing systems require a large number of users to contribute data. While several studies focus on developing efficient incentive mechanisms to foster user participation, data collection policies still require investigation. In this paper, we propose a novel distributed and sustainable framework for gathering information in cloud-based mobile crowd sensing systems with opportunistic reporting. The proposed framework minimizes cost of both sensing and reporting, while maximizing the utility of data collection and, as a result, the quality of contributed information. Analytical and simulation results provide performance evaluation for the proposed framework by providing a fine-grained analysis of the energy consumed. The simulations, performed in a real urban environment and with a large number of participants, aim at verifying the performance and scalability of the proposed approach on a large scale under different user arrival patterns. [less ▲]

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See detailCost-effective Strategies for the Regression Testing of Database Applications: Case study and Lessons Learned
Rogstad, Erik; Briand, Lionel UL

in Journal of Systems and Software (2016), 113

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See detailCost-Effectiveness of Neurostimulation in Parkinson's Disease With Early Motor Complications
Dams, J; Balzer-Geldsetzer, M; Siebert, U et al

in Movement Disorders : Official Journal of the Movement Disorder Society (2016), 31(8), 1183-1191

Background: Recent research efforts have focused on the effects of deep brain stimulation of the subthalamic nucleus (STN DBS) for selected patients with mild-to-moderate PD experiencing motor ... [more ▼]

Background: Recent research efforts have focused on the effects of deep brain stimulation of the subthalamic nucleus (STN DBS) for selected patients with mild-to-moderate PD experiencing motor complications. Objectives: We assessed the cost utility of subthalamic DBS compared with the best medical treatment for German patients below the age of 61 with early motor complications of PD. Methods: We applied a previously published Markov model that integrated health utilities based on EuroQoL and direct costs over patients’ lifetime adjusted to the German health care payer perspective (year of costing: 2013). Effectiveness was evaluated using the Parkinson’s Disease Questionnaire 39 summary index. We performed sensitivity analyses to assess uncertainty. Results: In the base-case analysis, the incremental cost-utility ratio for STN DBS compared to best medical treatment was 22,700 Euros per quality-adjusted life year gained. The time to, and costs for, battery exchange had a major effect on the incremental cost-utility ratios, but never exceeded a threshold of 50,000Euros per quality-adjusted life year. Conclusions: Our decision analysis supports the fact that STN DBS at earlier stages of the disease is cost-effective in patients below the age of 61 when compared with the best medical treatment in the German health care system. This finding was supported by detailed sensitivity analyses reporting robust results. Whereas the EARLYSTIM study has shown STN DBS to be superior to medical therapy with respect to quality of life for patients with early motor complications, this further analysis has shown its cost-effectiveness. [less ▲]

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See detailCostly financial intermediation in neoclassical growth theory
Mehra, Rajnish UL; Piguillem, F.; Prescott, E.C.

in Quantitative Economics (2011), 2

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See detailCosts and Benefits of Inter-Departmental Innovation Collaboration
Cuijpers, Maarten; Guenter, Hannes; Hussinger, Katrin UL

in Research Policy (2011)

Inter-departmental innovation collaboration facilitates innovation performance. At the same time, it has been identified as a source of increased coordination costs. Using organizational information ... [more ▼]

Inter-departmental innovation collaboration facilitates innovation performance. At the same time, it has been identified as a source of increased coordination costs. Using organizational information processing theory, this paper builds and tests hypotheses on the costs and benefits of innovation-related collaboration within firms. Based on a sample of 433 German manufacturing firms we show interdepartmental innovation collaboration to increase process innovation performance, but also to produce costs in terms of project delay and project termination. These costs, however, do not affect innovation performance at the firm level. This finding suggests firms to be well able to balance the costs and benefits of inter-departmental collaboration across their innovation project portfolio. Theoretical and managerial implications are discussed. [less ▲]

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See detailCoteaching in science education courses: Transforming teacher education through shared responsibility
Siry, Christina UL; Martin, Sonya; Baker, Shelley et al

in Murphy, Colette; Scantlebury, Kathryn (Eds.) Coteaching in international contexts: research and practice (2010)

This chapter focuses on the implementation of coteaching and cogenerative dialogue as foundational components in science teacher education courses. Our use of coteaching emphasizes sharing responsibility ... [more ▼]

This chapter focuses on the implementation of coteaching and cogenerative dialogue as foundational components in science teacher education courses. Our use of coteaching emphasizes sharing responsibility for teaching and learning science and science pedagogy with our students1. Cogenerative dialogues are conversations between classroom participants (teachers, students, researchers, etc.) to discuss classroom interactions and focus on improving teaching and learning. Coupled with coteaching, they serve as both a method for learning how to teach, as well as a methodological approach to learn about teaching. In this chapter we present our pedagogical perspectives and explore our research into the use of coteaching and cogenerative dialogues as an approach to teacher education courses. We have implemented this approach to counter the increasing trend towards the deprofessionalization of teachers, both at the K-12 and university levels. As we detail the development of our courses over time, we provide insights into how our epistemological understandings about teaching and learning have evolved to include sharing responsibility for teaching and learning with our students and how this practice has, in turn, informed our praxis as teacher educators. Building from Freirian notions of dialogue and participatory education, we explore how coteaching and cogenerative dialogue can be utilized as a tool for engaging students in a theory generative pedagogical approach to learning about teaching. Specifically, we focus on how sharing responsibility with our students for the teaching and learning that occurs in our courses has the potential to not only transform science teacher education, but also K-12 science education. In the sections that follow, we describe what we characterize as the de-professionalization of teaching and introduce coteaching and cogenerative dialogue as an engaged pedagogical approach teacher educators can utilize to support new and in-service teachers to “push back” at policies and mandates that de-emphasize the decision-making powers of professional teachers. [less ▲]

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See detailCouchsurfing - an empirical investigation into the online community as a platform for information sharing and tangential learning.
Max, Charles UL; Moreau, Richard UL

Scientific Conference (2012, October)

Couchsurfing is an online community with approximately 3 million profiles from over 230 countries worldwide (Del Rosso & Gréhan, 2010). Users can create a profile with minimal information about themselves ... [more ▼]

Couchsurfing is an online community with approximately 3 million profiles from over 230 countries worldwide (Del Rosso & Gréhan, 2010). Users can create a profile with minimal information about themselves free of charge, and post offers of free accommodation in their own homes for other users if desired. Interaction and exchange typically takes place around the activity of users negotiating accommodation in this manner. Users also avail of the online facilities to exchange and discuss topics of greatly diverse and dynamic nature (Peterson, & Siek, 2009). Communication practices in the Couchsurfing community are hybrid by nature given that interaction takes place not only online, but also between users who meet in physical life while travelling or for other social reasons (Pultar & Raubal, 2009). The present paper investigates processes of learning and knowledge sharing through socializing on the Couchsurfing website. We analyse the interactional features of online exchanges, discuss the key elements of the interaction and look at the outcomes and results. Our quest for prior research on the online activities of the Couchsurfing community yielded only few results (Lauterbach, 2009; Tan, 2010; Chowdhury, 2011), so that this study will hone further the specific interactions within this particular network. Research surrounding the topic of virtual/online communities is a relatively new field in social science (Tirado & Galvez, 2007) and is still busy to find consensual definitions for terms such as online communities, virtual spaces, and social media (Tirado & Galvez, 2007; Wilson et al., 2009; Kaplan & Haenlein 2010). Given this incipient phase of research in this field, the paper starts by defining the concept of virtual community more precisely for the present case. Second we investigate phenomena which were under low consideration so far, i.e. the field of learning and knowledge sharing within the social networking environment. According to Kaplan & Haenlein’s categories of social media (2010), the Couchsurfing online platform can be classified as both a content community and social networking site. The main objective of a content community is to share media content (text, photos, videos etc.) between users without obliging users to create a personal profile page. A social networking site encourages users to create personal profile sites and to invite friends and/or colleagues to follow the exchanges taking place at that page. As a combination of both, the Couchsurfing site is used for sharing a high amount of content between users, which facilitates learning as one of the primary focuses of our interaction analysis. More specifically, we use computer mediated discourse analysis (Herring, 2007) to look at interactions related to a) knowledge sharing b) learning, and c) (online) socializing Knowledge sharing has been defined by Wahlroos (2011) as that which “includes the exchange of information, ideas, opinion and expertise”. By analysing examples of online interactions from the website, we evidence how and to what extent knowledge sharing is of paramount importance and a primary outcome of these social exchanges. Informal and unintentional learning is increasingly emphasized with novel digital technologies, which are blurring the spheres of learning and everyday life. Often learning takes place in activities as a side-effect rather than a direct objective (UNESCO, 2005; Cross, 2007; Ala-Mutka, 2010). But, even failing to learn what is expected in a given situation usually involves learning something else instead (Wenger, 1998). Social networking sites promote engagement in communities (Rogoff, 1990), which are powerful means of creating and sharing new knowledge (Wahlroos, 2011). Forums and other tools through which members interact serve to stir discussion and spur interest. This ‘spidering of ideas’ evokes the contemporary notion of “tangential learning” (Portnow, 2008), which understands the instructor, tool, or learning environment to help familiarize learners with a body of knowledge rather than actively trying to teach them. The idea here is that learners will educate themselves if the tool can facilitate their introduction to topics they might like in a context that they already find engaging (Fischer, 2011). OUTCOMES The Couchsurfing website provides an abundance of resources about a broad number of topics. A thematic analysis of discussion threads revealed topics pertaining to world change, lifestyle improvement, and societal transformations. Our analysis has unveiled here a hosting ground for ‘virilisation’ of messages and ideas influencing movements such as occupy, anti-capitalism, vegetarianism or otherwise. The Couchsurfing website is in a sense a telling reflection of current societal issues, in all its dynamism, change and endless possibilities, generating radical ideas about how to live, where, how and what to be, regardless of age, background or otherwise (Chowdhury, 2011). Our analysis revealed a wealth of evidence of knowledge sharing, and unveiled many instances where we inferred that learning was happening as for example instances where one user acknowledges another user’s provision of information, or admits to have found it of interest. Labelling such interactions as instances of learning has to be done always with prudence as one can never witness learning per se, but only interactions whereby learning would be assumed to have taken place within the norms of social discourse and behaviour. Similar difficulties arose when endeavouring to identify the dynamics of knowledge sharing as an empirical phenomenon. However instances of knowledge sharing are more self-evident than learning, as sharing by definition does not require knowing whether the knowledge gets assimilated or not. Our analysis allows to characterize communities whose members interact in real and digital life more precisely as far as regards relationships between participants, interdependence during exchanges, accumulation of shared experience as grounds for membership. Hence, a qualitative study into the concept of tangential learning as a result of online social interactions is already in progress in order to further investigate to what extent people actually do learn, and acknowledge that they do so when interacting with other users through online platforms such as Couchsurfing. [less ▲]

Detailed reference viewed: 269 (9 UL)