TY - CONF AB - Online social networks are attracting billions of nowadays, both on a global scale as well as in social enterprise networks. Using distributed hash tables and peer-to-peer technology allows online social networks to be operated securely and efficiently only by using the resources of the user devices, thus alleviating censorship or data misuse by a single network operator. In this paper, we address the challenges that arise in implementing reliably and conveniently to use distributed data structures, such as lists or sets, in such a distributed hash-tablebased online social network. We present a secure, distributed list data structure that manages the list entries in several buckets in the distributed hash table. The list entries are authenticated, integrity is maintained and access control for single users and also groups is integrated. The approach for secure distributed lists is also applied for prefix trees and sets, and implemented and evaluated in a peer-to-peer framework for social networks. Evaluation shows that the distributed data structure is convenient and efficient to use and that the requirements on security hold. AU - Janiuk, Jens AU - Mäcker, Alexander AU - Graffi, Kalman ID - 367 T2 - Proceedings of the International Conference on Collaboration Technologies and Systems (CTS) TI - Secure Distributed Data Structures for Peer-to-Peer-based Social Networks ER - TY - CHAP AU - Daunert, Anna Liza AU - Harteis, Christian ED - Pelet, J.-E. ID - 3678 T2 - E-Learning 2.0 Technologies and Web Applications in Higher Education TI - Pre-service teachers’ perspectives and practices in utilizing ubiquitous technologies for academic-oriented learning and knowledge management ER - TY - CONF AB - We consider the problem of scheduling a number of jobs on $m$ identical processors sharing a continuously divisible resource. Each job j comes with a resource requirement r_j \in {0,1}. The job can be processed at full speed if granted its full resource requirement. If receiving only an x-portion of r_j, it is processed at an x-fraction of the full speed. Our goal is to find a resource assignment that minimizes the makespan (i.e., the latest completion time). Variants of such problems, relating the resource assignment of jobs to their \emph{processing speeds}, have been studied under the term discrete-continuous scheduling. Known results are either very pessimistic or heuristic in nature.In this paper, we suggest and analyze a slightly simplified model. It focuses on the assignment of shared continuous resources to the processors. The job assignment to processors and the ordering of the jobs have already been fixed. It is shown that, even for unit size jobs, finding an optimal solution is NP-hard if the number of processors is part of the input. Positive results for unit size jobs include an efficient optimal algorithm for 2 processors. Moreover, we prove that balanced schedules yield a 2-1/m-approximation for a fixed number of processors. Such schedules are computed by our GreedyBalance algorithm, for which the bound is tight. AU - Brinkmann, Andre AU - Kling, Peter AU - Meyer auf der Heide, Friedhelm AU - Nagel, Lars AU - Riechers, Sören AU - Suess, Tim ID - 368 T2 - Proceedings of the 26th ACM Symposium on Parallelism in Algorithms and Architectures (SPAA) TI - Scheduling Shared Continuous Resources on Many-Cores ER - TY - CHAP AU - Goller, Michael AU - Harteis, Christian ED - Harteis, Christian ED - Rausch, Andreas ED - Seifried, Jürgen ID - 3685 T2 - Discourses on Professional Learning TI - Employing agency in academic settings: Doctoral students shaping their own experiences ER - TY - CHAP AU - Harteis, Christian AU - Goller, Michael ED - Halttunen, Timo ED - Koivisto, Mari ED - Billett, Stephen ID - 3686 T2 - Promoting, assessing, recognizing and certifying lifelong learning TI - New skills for new jobs: Work agency as a necessary condition for successful lifelong learning ER - TY - GEN AB - RSA Full Domain Hash ist im Zufallsorakelmodell ein EUF-CMA sicheres Signaturverfahren (existentially unforgeable under chosen-message attacks). Der Sicherheitsbeweis wird unter anderem in der Vorlesung Einf{\"u}hrung in die Kryptographie vorgestellt. Auch bei einer genaueren Analyse verliert man bei der Reduktion einen Faktor \nicefrac{1}{q_{s}}(wobei q_{s}die Anzahl der Anfragen an das Signaturorakel darstellt), was f{\"u}r die Praxis in relativ großen Systemparametern (RSA-Modul) resultiert [1].Seit der Ver{\"o}ffentlichung von [2] wurde geglaubt, dass der Faktor \nicefrac{1}{q_{s}}optimal ist. Erst zehn Jahre sp{\"a}ter offenbarten die Autoren von [3] einen Fehler in [2] und zeigten eine bessere Reduktion allerdings unter einer etwas st{\"a}rkeren Sicherheitsannahme.Die Ergebnisse aus [3] lassen sich auf PSS-Verfahren (Probabilistic Signature Scheme), das z.B. in PKCS #1 benutzt wird, {\"u}bertragen und sind somit von großer Bedeutung f{\"u}r die Praxis. Weiterhin sind die in den Beweisen verwendete Techniken n{\"u}tzlich auch bei anderen kryptographischen Verfahren.In Rahmen dieser Arbeit sollen die entsprechenden Sicherheitsbeweise aufgearbeitet und dessen Auswirkungen f{\"u}r die Praxis analysiert werden.[1] J.S. Coron, “On the Exact Security of Full Domain Hash”, CRYPTO 2000. LNCS 1880, pp. 229-235, 2000.[2] J.S. Coron, “Optimal security proofs for PPS and other signature schemes”, EUROCRYPT 2002. LNCS 2332, pp 272-287, 2002.[3] S.A. Kakvi and E. Kiltz, “Optimal Security Proofs for Full Domain Hash, Revisited”, in EUROCRYPT 2012. LNCS 7237, pp 537-553, 2012. AU - Rath, Timo ID - 369 TI - RSA-Full Domain Hash Revisited ER - TY - JOUR AB - When taxes on capital or wealth are levied, in most countries companies have to be assessed in terms of their market value (MV). Estimating the MV of private companies for tax purposes is a challenging task for tax authorities as MVs are not available. In this study, I empirically analyse to what extent an accounting-based tax valuation method for private companies, a simplified residual income model, succeeds in matching the MV. I refer to the mandatory Standardised Combination Model that is a special case of methods commonly used in several countries. In the absence of market prices for private companies, I use a sample of small German public companies as a proxy. I validate this approach using a sensitivity analysis that involves matching the sample of public companies with that of private companies. The results imply that the mandatory Standardised Combination Model leads to a severe unequal treatment not only between public and private companies but also among private companies across and within industries. Furthermore, I simulate the effects of variation in the key parameters and highlight their impact on the approximation quality of the Standardised Combination Method. The findings are relevant to tax reform discussions as well as to tax policy-makers and practitioners in many countries. AU - Müller, Jens ID - 3699 IS - 1 JF - European Accounting Review KW - Challenge of Assessing KW - Tax Purposes TI - The challenge of assessing the market value of private companies using a standardised combination method for tax purposes--Lessons to be learnt from past experience ER - TY - CONF AB - Max-min fairness (MMF) is a widely known approach to a fair allocation of bandwidth to each of the users in a network. This allocation can be computed by uniformly raising the bandwidths of all users without violating capacity constraints. We consider an extension of these allocations by raising the bandwidth with arbitrary and not necessarily uniform time-depending velocities (allocation rates). These allocations are used in a game-theoretic context for routing choices, which we formalize in progressive filling games (PFGs).We present a variety of results for equilibria in PFGs. We show that these games possess pure Nash and strong equilibria. While computation in general is NP-hard, there are polynomial-time algorithms for prominent classes of Max-Min-Fair Games (MMFG), including the case when all users have the same source-destination pair. We characterize prices of anarchy and stability for pure Nash and strong equilibria in PFGs and MMFGs when players have different or the same source-destination pairs. In addition, we show that when a designer can adjust allocation rates, it is possible to design games with optimal strong equilibria. Some initial results on polynomial-time algorithms in this direction are also derived. AU - Harks, Tobias AU - Höfer, Martin AU - Schewior, Kevin AU - Skopalik, Alexander ID - 370 T2 - Proceedings of the 33rd Annual IEEE International Conference on Computer Communications (INFOCOM'14) TI - Routing Games with Progressive Filling ER - TY - CONF AB - In this work we present the first distributed storage system that is provably robust against crash failures issued by an adaptive adversary, i.e., for each batch of requests the adversary can decide based on the entire system state which servers will be unavailable for that batch of requests. Despite up to \gamma n^{1/\log\log n} crashed servers, with \gamma>0 constant and n denoting the number of servers, our system can correctly process any batch of lookup and write requests (with at most a polylogarithmic number of requests issued at each non-crashed server) in at most a polylogarithmic number of communication rounds, with at most polylogarithmic time and work at each server and only a logarithmic storage overhead. Our system is based on previous work by Eikel and Scheideler (SPAA 2013), who presented IRIS, a distributed information system that is provably robust against the same kind of crash failures. However, IRIS is only able to serve lookup requests. Handling both lookup and write requests has turned out to require major changes in the design of IRIS. AU - Scheideler, Christian AU - Setzer, Alexander AU - Eikel, Martina ID - 371 T2 - Proceedings of the 18th International Conference on Principles of Distributed Systems (OPODIS) TI - RoBuSt: A Crash-Failure-Resistant Distributed Storage System ER - TY - CHAP AU - Harteis, Christian ED - Arnold, Rolf ED - Wolf, K ID - 3718 T2 - Herausforderung kompetenzorientierte Hochschule TI - Auswirkungen des Bologna-Prozesses: Eine Expertise der Hochschuldidaktik ER - TY - CHAP AU - Harteis, Christian ED - Sinclair, Martha ID - 3719 T2 - Handbook of intuition research methodology TI - Investigating intuition under the perpective of expertise: Experiences from two experimental studies ER - TY - CONF AB - In the near future many more compute resources will be available at different geographical locations. To minimize the response time of requests, application servers closer to the user can hence be used to shorten network round trip times. However, this advantage is neutralized if the used data centre is highly loaded as the processing time of re- quests is important as well. We model the request response time as the network round trip time plus the processing time at a data centre.We present a capacitated facility location problem formal- ization where the processing time is modelled as the sojourn time of a queueing model. We discuss the Pareto trade-off between the number of used data centres and the resulting response time. For example, using fewer data centres could cut expenses but results in high utilization, high response time, and smaller revenues.Previous work presented a non-linear cost function. We prove its convexity and exploit this property in two ways: First, we transform the convex model into a linear model while controlling the maximum approximation error. Sec- ond, we used a convex solver instead of a slower non-linear solver. Numerical results on network topologies exemplify our work. AU - Keller, Matthias AU - Karl, Holger ID - 372 T2 - Proceedings of the SIGCOMM workshop on Distributed cloud computing TI - Response Time-Optimized Distributed Cloud Resource Allocation ER - TY - GEN AU - Pahl, David ID - 373 TI - Reputationssysteme für zusammengesetzte Dienstleistungen ER - TY - CONF AB - Run-time reconfiguration provides an opportunity to increase performance, reduce cost and improve energy efficiency in FPGA-based systems. However, run-time reconfigurable systems are more complex to implement than static only systems. This increases time to market, and introduces run-time overhead into the system. Our research aims to raise the abstraction level to develop run-time reconfigurable systems. We present operating system extensions which enable seamless integration of run-time reconfigurable hardware threads into applications. To improve resource utilization, the hardware threads are placed on a fine granularity tile grid. We take advantage of a relocatable module placer targeting modern FPGA to manage the reconfigurable area. The module placer accurately models the FPGA resources to compute feasible placement locations for the hardware threads at run-time. Finally, we evaluate our work by means of a case study that consists of a synthetic application to validate the functionality and performance of the implementation. The results show a reduction in reconfiguration time of up to 42% and more than double resource utilization. AU - Wold, Alexander AU - Agne, Andreas AU - Torresen, Jim ED - Goehringer, Diana ED - Santambrogio, MarcoDomenico ED - Cardoso, JoãoM.P. ED - Bertels, Koen ID - 374 T2 - Proceedings of the 10th International Symposium on Reconfigurable Computing: Architectures, Tools, and Applications TI - Relocatable Hardware Threads in Run-Time Reconfigurable Systems ER - TY - JOUR AB - Many software development, planning, or analysis tasks require an up-to-date software architecture documentation. However, this documentation is often outdated, unavailable, or at least not available as a formal model which analysis tools could use. Reverse engineering methods try to fill this gap. However, as they process the system’s source code, they are easily misled by design deficiencies (e.g., violations of component encapsulation) which leaked into the code during the system’s evolution. Despite the high impact of design deficiencies on the quality of the resulting software architecture models, none of the surveyed related works is able to cope with them during the reverse engineering process. Therefore, we have developed the Archimetrix approach which semi-automatically recovers the system’s concrete architecture in a formal model while simultaneously detecting and removing design deficiencies. We have validated Archi metrix on a case-study system and two implementation variants of the CoCoME benchmark system. Results show that the removal of relevant design deficiencies leads to an architecture model which more closely matches the system’s conceptual architecture. AU - von Detten, Markus AU - Platenius, Marie Christin AU - Becker, Steffen ID - 375 IS - 4 JF - Journal of Software and Systems Modeling TI - Reengineering Component-Based Software Systems with Archimetrix ER - TY - THES AB - Radio access networks (RANs) have become one of the largest energy consumers of communication technology [LLH+13] and their energy consumption is predicted to increase [FFMB11]. To reduce the energy consumption of RANs different techniques have been proposed. One of the most promising techniques is the use of a low-power sleep mode. However, a sleep mode can also reduce the performance. In this dissertation, I quantify how much energy can be conserved with a sleep mode and which negative effects it has on the performance of RANs. Additionally, I analyze how a sleep mode can be enabled more often and how the performance can be kept high. First, I quantify the effect of power-cycle durations on energy consumption and latency in an abstract queuing system. This results in a trade-off between energy consumption and latency for a single base station (BS). Second, I show that considering a network as a whole (instead of each BS individually) allows the energy consumption to be reduced even further. After these analyses, which are not specific for RANs, I study RANs for the rest of the dissertation. RANs need to both detect and execute the requests of users. Because detection and execution of requests have different requirements, I analyze them independently. I quantify how the number of active BSs can be reduced if the detection ranges of BSs are increased by cooperative transmissions. Next, I analyze how more BSs can be deactivated if the remaining active BSs cooperate to transmit data to the users. However, in addition to increasing the range, cooperative transmissions also radiate more power. This results in higher interference for other users which slows their transmissions down and, thus, increases energy consumption. Therefore, I describe how the radiated power of cooperative transmissions can be reduced if instantaneous channel knowledge is available. Because the implementation in real hardware is impractical for demonstration purposes, I show the results of a simulation that incorporates all effects I studied analytically earlier. In conclusion, I show that a sleep mode can reduce the energy consumption of RANs if applied correctly. To apply a sleep mode correctly, it is necessary to consider power-cycle durations, power profiles, and the interaction of BSs. When this knowledge is combined the energy consumption of RANs can be reduced with only a slight loss of performance. Because this results in a trade-off between energy consumption and performance, each RAN operator has to decide which trade-off is preferred. AU - Herlich, Matthias ID - 376 TI - Reducing Energy Consumption of Radio Access Networks ER - TY - JOUR AB - The Chord peer-to-peer system is considered, together with CAN, Tapestry and Pastry, as one of the pioneering works on peer-to-peer distributed hash tables (DHT) that inspired a large volume of papers and projects on DHTs as well as peer-to-peer systems in general. Chord, in particular, has been studied thoroughly, and many variants of Chord have been presented that optimize various criteria. Also, several implementations of Chord are available on various platforms. Though Chord is known to be very efficient and scalable and it can handle churn quite well, no protocol is known yet that guarantees that Chord is self-stabilizing, i.e., the Chord network can be recovered from any initial state in which the network is still weakly connected. This is not too surprising since it is known that the Chord network is not locally checkable for its current topology. We present a slight extension of the Chord network, called Re-Chord (reactive Chord), that turns out to be locally checkable, and we present a self-stabilizing distributed protocol for it that can recover the Re-Chord network from any initial state, in which the n peers are weakly connected, in O(nlogn) communication rounds. We also show that our protocol allows a new peer to join or an old peer to leave an already stable Re-Chord network so that within O(logn)^2) communication rounds the Re-Chord network is stable again. AU - Kniesburges, Sebastian AU - Koutsopoulos, Andreas AU - Scheideler, Christian ID - 378 IS - 3 JF - Theory of Computing Systems TI - Re-Chord: A Self-stabilizing Chord Overlay Network ER - TY - CONF AB - In the leasing variant of Set Cover presented by Anthony et al.[1], elements U arrive over time and must be covered by sets from a familyF of subsets of U. Each set can be leased for K different periods of time.Let |U| = n and |F| = m. Leasing a set S for a period k incurs a cost ckS and allows S to cover its elements for the next lk time steps. The objectiveis to minimize the total cost of the sets leased, such that elements arrivingat any time t are covered by sets which contain them and are leased duringtime t. Anthony et al. [1] gave an optimal O(log n)-approximation forthe problem in the offline setting, unless P = NP [22]. In this paper, wegive randomized algorithms for variants of Set Cover Leasing in the onlinesetting, including a generalization of Online Set Cover with Repetitionspresented by Alon et al. [2], where elements appear multiple times andmust be covered by a different set at each arrival. Our results improve theO(log2(mn)) competitive factor of Online Set Cover with Repetitions [2]to O(log d log(dn)) = O(logmlog(mn)), where d is the maximum numberof sets an element belongs to. AU - Abshoff, Sebastian AU - Markarian, Christine AU - Meyer auf der Heide, Friedhelm ID - 379 T2 - Proceedings of the 8th Annual International Conference on Combinatorial Optimization and Applications (COCOA) TI - Randomized Online Algorithms for Set Cover Leasing Problems ER - TY - CONF AB - Network creation games model the creation and usage costs of networks formed by n selfish nodes. Each node v can buy a set of edges, each for a fixed price α > 0. Its goal is to minimize its private costs, i.e., the sum (SUM-game, Fabrikant et al., PODC 2003) or maximum (MAX-game, Demaine et al., PODC 2007) of distances from v to all other nodes plus the prices of the bought edges. The above papers show the existence of Nash equilibria as well as upper and lower bounds for the prices of anarchy and stability. In several subsequent papers, these bounds were improved for a wide range of prices α. In this paper, we extend these models by incorporating quality-of-service aspects: Each edge cannot only be bought at a fixed quality (edge length one) for a fixed price α. Instead, we assume that quality levels (i.e., edge lengths) are varying in a fixed interval [βˇ,β^] , 0 series = {LNCS} AU - Cord-Landwehr, Andreas AU - Mäcker, Alexander AU - Meyer auf der Heide, Friedhelm ID - 380 T2 - Proceedings of the 10th International Conference on Web and Internet Economics (WINE) TI - Quality of Service in Network Creation Games ER - TY - CONF AU - Brüseke, Frank AU - Wachsmuth, Henning AU - Engels, Gregor AU - Becker, Steffen ID - 3805 IS - 12 T2 - Proceedings of the 4th International Symposium on Autonomous Minirobots for Research and Edutainment TI - PBlaman: performance blame analysis based on Palladio contracts ER - TY - CONF AB - This paper explores how cloud provider competition influences instance pricing in an IaaS (Infrastructure-as-a-Service) market. When reserved instance pricing includes an on-demand price component in addition to a reservation fee (two-part tariffs), different providers might offer different price combinations, where the client’s choice depends on its load profile. We investigate a duopoly of providers and analyze stable market prices in two-part tariffs. Further, we study offers that allow a specified amount of included usage (three-part tariffs). Neither two-part nor three-part tariffs produce an equilibrium market outcome other than a service pricing that equals production cost, i.e., complex price structures do not significantly affect the results from ordinary Bertrand competition. AU - Künsemöller, Jörn AU - Brangewitz, Sonja AU - Karl, Holger AU - Haake, Claus-Jochen ID - 382 T2 - Proceedings of the 2014 IEEE International Conference on Services Computing (SCC) TI - Provider Competition in Infrastructure-as-a-Service ER - TY - CONF AB - Proof-carrying code approaches aim at safe execution of untrusted code by having the code producer attach a safety proof to the code which the code consumer only has to validate. Depending on the type of safety property, proofs can however become quite large and their validation - though faster than their construction - still time consuming. In this paper we introduce a new concept for safe execution of untrusted code. It keeps the idea of putting the time consuming part of proving on the side of the code producer, however, attaches no proofs to code anymore but instead uses the proof to transform the program into an equivalent but more efficiently verifiable program. Code consumers thus still do proving themselves, however, on a computationally inexpensive level only. Experimental results show that the proof effort can be reduced by several orders of magnitude, both with respect to time and space. AU - Wonisch, Daniel AU - Schremmer, Alexander AU - Wehrheim, Heike ID - 383 T2 - Proceedings of the Software Engineering Conference (SE) TI - Programs from Proofs -- Approach and Applications ER - TY - CONF AB - Reputation systems provide reputation values of rated parties to users. These reputation values, typically aggregations of individual user ratings, shall be reliable, i.e. should enable a realistic assessment of the probability that the rated party behaves as expected in a transaction. In order for the reputation values to stay reliable and, thus, for the reputation system to provide a benefit, the system needs to be resistant against manipulations by users, the rated parties trying to improve their reputation values, and even against competitors trying to worsen a reputation value. At the same time, a reputation system shall provide privacy protection for users: rated parties shall not be able to learn who provided a certain rating. Otherwise users might not take part in the system as they fear bad feedback in revenge for bad ratings, or users do not want to be connected to certain transactions based on their provided ratings. In this paper we come up with a solution that provides both, reliability of reputation values on the one hand, and privacy protection for users on the other hand. In contrast to related work, our solution only makes use of a single reputation provider that needs to be trusted (to a certain extent) and does not require any bulletin boards to be present in the system. We make use of the Paillier cryptosystem to provide an aggregation of individual user ratings in a way that no party can learn which user provided a certain rating. AU - Petrlic, Ronald AU - Lutters, Sascha AU - Sorge, Christoph ID - 384 T2 - Proceedings of the 29th Symposium On Applied Computing (SAC) TI - Privacy-Preserving Reputation Management ER - TY - THES AU - Petrlic, Ronald ID - 385 TI - Privacy-Preserving Multiparty Digital Rights Management ER - TY - CONF AB - We present a privacy-preserving multiparty DRM scheme that does not need a trusted third party. Users anonymously buy content from content providers and anonymously execute it at content execution centers. The executions are unlinkable to each other. The license check is performed as part of the used ciphertext-policy attribute-based encryption (CP-ABE) and, thus, access control is cryptographically enforced. The problem of authorization proof towards the key center in an ABE scheme is solved by a combination with anonymous payments. AU - Petrlic, Ronald AU - Sorge, Christoph ID - 386 T2 - Proceedings of the Sixth IFIP International Conference on New Technologies, Mobility and Security (NTMS) TI - Privacy-Preserving Digital Rights Management based on Attribute-based Encryption ER - TY - JOUR AB - This article studies the design of medium access control (MAC) protocols for wireless networks that are provably robust against arbitrary and unpredictable disruptions (e.g., due to unintentional external interference from co-existing networks or due to jamming). We consider a wireless network consisting of a set of n honest and reliable nodes within transmission (and interference) range of each other, and we model the external disruptions with a powerful adaptive adversary. This adversary may know the protocol and its entire history and can use this knowledge to jam the wireless channel at will at any time. It is allowed to jam a (1 − )-fraction of the timesteps, for an arbitrary constant > 0 unknown to the nodes. The nodes cannot distinguish between the adversarial jamming or a collision of two or more messages that are sent at the same time. We demonstrate, for the first time, that there is a local-control MAC protocol requiring only very limited knowledge about the adversary and the network that achieves a constant (asymptotically optimal) throughput for the nonjammed time periods under any of the aforementioned adversarial strategies. The derived principles are also useful to build robust applications on top of the MAC layer, and we present an exemplary study for leader election, one of the most fundamental tasks in distributed computing. AU - Awerbuch, Baruch AU - Richa, Andrea W. AU - Scheideler, Christian AU - Schmid, Stefan AU - Zhang, Jin ID - 387 IS - 4 JF - Transactions on Algorithms TI - Principles of Robust Medium Access and an Application to Leader Election ER - TY - CONF AU - Wachsmuth, Henning AU - Trenkmann, Martin AU - Stein, Benno AU - Engels, Gregor ID - 3877 T2 - Proceedings of COLING 2014, the 25th International Conference on Computational Linguistics: Technical Papers TI - Modeling Review Argumentation for Robust Sentiment Analysis ER - TY - GEN AB - This article presents a new approach for representing and processing abstract optimization models. Confronted with model and data integration tasks for distributed Decision Support Systems which are especially composed out of software services, we describe model constituents such as constraints both structurally and semantically. Within our approach, typed model constituents can be integrated into complete models and the instantiation of model constituents itself with data and data models can be wrapped into semantic software services. Besides others, this supports the automated generation of adaptors and the search for and composition of services. The basic idea of our approach is to represent the optimization models as instance knowledge of different ontologies for both optimization and application domains. By separating the model expression structure from the goal and constraint conceptualizations predefined modeling constructs can be reused, where we do not only separate the model structure from data, but can also abstract the structure from a specific data model. We present an XML and ontology-query based approach for this separation and demonstrate the resulting flexible model integration procedure out of reusable goal and constraint types on a network flow problem. AU - Stapel, Florian AU - Suhl, Lena ID - 389 TI - Ontology-based Representation of Optimization Models ER - TY - JOUR AB - The incidenceofthin-film-guided, in-planeunguidedwavesatobliqueanglesonstraightdiscontinuities of dielectricslabwaveguides,anearlyproblemofintegratedoptics,isbeingre-considered.The3-D frequencydomainMaxwellequationsreducetoaparametrizedinhomogeneousvectorialproblemona 2-D computationaldomain,withtransparent-influx boundaryconditions.Weproposearigorousvec- torial solverbasedonsimultaneousexpansionsintopolarizedlocalslabeigenmodesalongthetwo orthogonal crosssectioncoordinates(quadridirectionaleigenmodepropagationQUEP).Thequasi-ana- lytical schemeisapplicabletoconfigurations with — in principle — arbitrary crosssectiongeometries. Examples forahigh-contrastfacetofanasymmetricslabwaveguide,forthelateralexcitationofa channel waveguide,andforastepdiscontinuitybetweenslabwaveguidesofdifferentthicknessesare discussed. AU - Hammer, Manfred ID - 3890 JF - Optics Communications KW - tet_topic_waveguide KW - tet_topic_numerics SN - 0030-4018 TI - Oblique incidence of semi-guided waves on rectangular slab waveguide discontinuities: A vectorial QUEP solver VL - 338 ER - TY - JOUR AB - In software markets of the future, customer-specific software will be developed on demand based on distributed software and hardware services. Based on a customer-specific request, available service offers have to be discovered and composed into sophisticated IT services that fulfill the customer's request.A prerequisite of this vision are rich service descriptions, which comprise structural as well as behavioral aspects of the services, otherwise an accurate service discovery and composition is not possible. However, automatic matching of service requests and offers specified in rich service descriptions for the purpose of service discovery is a complex task, due to the multifaceted heterogeneity of the service partners. This heterogeneity includes the use of different specification languages, different underlying ontologies, or different levels of granularity in the specification itself.In this article, we present a comprehensive approach for service discovery and composition, which overcomes the underlying heterogeneity of the service partners. Based on a realistic case study of our industrial partner from the e-tourism domain, we first introduce an automatic matching mechanism for service requests and offers specified in a rich service description language. In addition, we propose an automatic service composition approach, which determines possible service compositions by composing the service protocols through a composition strategy based on labeled transition systems. AU - Huma, Zille AU - Gerth, Christian AU - Engels, Gregor ID - 390 IS - 3-4 JF - Computer Science - Research and Development TI - On-the-Fly Computing: Automatic Service Discovery and Composition in Heterogeneous Domains ER - TY - JOUR AU - Abu Quba Rana, Chamsi AU - Hassas, Salima AU - Usama, Fayyad AU - Alshomary, Milad AU - Gertosio, Christine ID - 3905 JF - 2014 IEEE/ACS 11th International Conference on Computer Systems and Applications (AICCSA) TI - iSoNTRE: The Social Network Transformer into Recommendation Engine ER - TY - GEN AU - Feldkord, Björn ID - 391 TI - On Variants of the Page Migration Problem ER - TY - CONF AU - Davis, Niki AU - Eickelmann, Birgit ID - 28936 T2 - Proceedings of the American Educational Research Association annual meeting (AERA) TI - The restructuring of schooling with digital technologies and implications for policy makers and practitioners ER - TY - CONF AU - Eickelmann, Birgit AU - Vennemann, Mario AU - Gerick, Julia AU - Lorenz, Ramona ID - 28937 T2 - Proceedings of the American Educational Research Association annual meeting (AERA) TI - Computer and internet in primary mathematics and science education and its relationship with student achievement– International findings from TIMSS 2011 ER - TY - CONF AU - Vennemann, Mario AU - Eickelmann, Birgit ID - 28938 T2 - Proceedings of the American Educational Research Association annual meeting (AERA) TI - Can we predict usage out of possession? – A home digital resources (HDR) scale to describe students’ digital learning resources in primary schools ER - TY - CONF AU - Lai, Kwok-Wing AU - Eickelmann, Birgit AU - Fisser, Petra AU - Khaddage, Ferial AU - Knezek, Gerald AU - Webb, Mary AU - Davis, Niki AU - Erstad, Ola AU - Gibson, David C. ID - 28939 T2 - Proceedings of KeyCIT Conference 2014 TI - Tackling Educational Challenges in a Digitally Networked World: Strategies developed from the EDUsummIT 2013 ER - TY - DATA AU - Drossel, Kerstin AU - Bos, Wilfried AU - Zieger, Laura ID - 28993 TI - Kinder- und Jugendarbeit in Dortmund. Studie zur Situation freiwillig Mitarbeitender in der Dortmunder Kinder- und Jugendarbeit ER - TY - GEN AU - Brauer, Sascha ID - 2900 TI - A Probabilistic Expectation Maximization Algorithm for Multivariate Laplacian Mixtures ER - TY - JOUR AU - Ackermann, Marcel Rudolf AU - Blömer, Johannes AU - Kuntze, Daniel AU - Sohler, Christian ID - 2976 JF - Algorithmica TI - Analysis of Agglomerative Clustering VL - 69 ER - TY - CONF AU - Blömer, Johannes AU - Bujna, Kathrin AU - Kuntze, Daniel ID - 2977 SN - 9781479952090 T2 - 2014 22nd International Conference on Pattern Recognition TI - A Theoretical and Experimental Comparison of the EM and SEM Algorithm ER - TY - JOUR AU - Jager, Tibor ID - 3127 IS - 7 JF - Datenschutz und Datensicherheit TI - Die Zukunft der Kryptographie ER - TY - CONF AU - Fleischhacker, Nils AU - Jager, Tibor AU - Schröder, Dominique ID - 3128 T2 - Advances in Cryptology - ASIACRYPT 2014 - 20th International Conference on the Theory and Application of Cryptology and Information Security, Kaoshiung, Taiwan, R.O.C., December 7-11, 2014. Proceedings, Part I TI - On Tight Security Proofs for Schnorr Signatures ER - TY - JOUR AU - Schneider, Steve AU - Treharne, Helen AU - Wehrheim, Heike ID - 3167 IS - 2 JF - Formal Asp. Comput. TI - The behavioural semantics of Event-B refinement ER - TY - JOUR AU - Tofan, Bogdan AU - Travkin, Oleg AU - Schellhorn, Gerhard AU - Wehrheim, Heike ID - 3168 JF - Sci. Comput. Program. TI - Two approaches for proving linearizability of multiset ER - TY - JOUR AU - Schellhorn, Gerhard AU - Derrick, John AU - Wehrheim, Heike ID - 3169 IS - 4 JF - {ACM} Trans. Comput. Log. TI - A Sound and Complete Proof Technique for Linearizability of Concurrent Data Structures ER - TY - CONF AU - Derrick, John AU - Dongol, Brijesh AU - Schellhorn, Gerhard AU - Tofan, Bogdan AU - Travkin, Oleg AU - Wehrheim, Heike ED - B. Jones, Cliff ED - Pihlajasaari, Pekka ED - Sun, Jun ID - 3170 T2 - {FM} 2014: Formal Methods - 19th International Symposium, Singapore, May 12-16, 2014. Proceedings TI - Quiescent Consistency: Defining and Verifying Relaxed Linearizability ER - TY - CONF AU - Travkin, Oleg AU - Wehrheim, Heike ED - Yahav, Eran ID - 3171 T2 - Hardware and Software: Verification and Testing - 10th International Haifa Verification Conference, {HVC} 2014, Haifa, Israel, November 18-20, 2014. Proceedings TI - Handling {TSO} in Mechanized Linearizability Proofs ER - TY - CONF AU - Isenberg, Tobias AU - Wehrheim, Heike ED - Merz, Stephan ED - Pang, Jun ID - 3172 T2 - Formal Methods and Software Engineering - 16th International Conference on Formal Engineering Methods, {ICFEM} 2014, Luxembourg, Luxembourg, November 3-5, 2014. Proceedings TI - Timed Automata Verification via {IC3} with Zones ER - TY - CONF AU - A. Schneider, Steve AU - Treharne, Helen AU - Wehrheim, Heike AU - M. Williams, David ED - Albert, Elvira ED - Sekerinski, Emil ID - 3173 T2 - Integrated Formal Methods - 11th International Conference, {IFM} 2014, Bertinoro, Italy, September 9-11, 2014, Proceedings TI - Managing {LTL} Properties in Event-B Refinement ER - TY - JOUR AU - Schneider, Steve AU - Treharne, Helen AU - Wehrheim, Heike AU - M. Williams, David ID - 3174 JF - CoRR TI - Managing {LTL} properties in Event-B refinement ER - TY - JOUR AU - Isenberg, Tobias AU - Wehrheim, Heike ID - 3175 JF - CoRR TI - Proof-Carrying Hardware via {IC3} ER - TY - JOUR AU - Stimming, Madlen AU - Mesch, Christina M. AU - Kersting, Mathilde AU - Libuda, Lars ID - 27041 JF - European Journal of Nutrition SN - 1436-6207 TI - Fish and rapeseed oil consumption in infants and mothers: dietary habits and determinants in a nationwide sample in Germany ER - TY - JOUR AU - Stimming, Madlen AU - Mesch, Christina M. AU - Kersting, Mathilde AU - Kalhoff, Hermann AU - Demmelmair, Hans AU - Koletzko, Berthold AU - Schmidt, Anne AU - Böhm, Volker AU - Libuda, Lars ID - 27042 JF - Journal of Agricultural and Food Chemistry SN - 0021-8561 TI - Vitamin E Content and Estimated Need in German Infant and Follow-On Formulas With and Without Long-Chain Polyunsaturated Fatty Acids (LC-PUFA) Enrichment ER - TY - JOUR AU - Vyncke, Krishna AU - Huybrechts, Inge AU - Van Winckel, Myriam AU - Cuenca Garcia, Magdalena AU - Labayen, Idoia AU - Gottrand, Frederic AU - Widhalm, Kurt AU - Leclercq, Catherine AU - Libuda, Lars AU - Manios, Yannis AU - Sjostrom, Michael AU - Molnar, Denes AU - Moreno, Luis A. AU - Gonzalez-Gross, Marcela AU - Spinneker, André AU - Perez de Heredia, Fatima AU - Plada, Maria AU - De Henauw, Stefaan ID - 27044 JF - Lipids SN - 0024-4201 TI - Dietary Lipid Intake only Partially Influences Variance in Serum Phospholipid Fatty Acid Composition in Adolescents: Impact of Other Dietary Factors ER - TY - JOUR AB - The present study aimed to investigate the relationships between macronutrient intake and serum lipid profile in adolescents from eight European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) cross-sectional study (2006–7), and to assess the role of body fat-related variables in these associations. Weight, height, waist circumference, skinfold thicknesses, total cholesterol, HDL-cholesterol (HDL-C), LDL-cholesterol, TAG, apoB and apoA1 were measured in 454 adolescents (44 % boys) aged 12·5–17·5 years. Macronutrient intake (g/4180 kJ per d (1000 kcal per d)) was assessed using two non-consecutive 24 h dietary recalls. Associations were evaluated by multi-level analysis and adjusted for sex, age, maternal education, centre, sum of four skinfolds, moderate-to-vigorous physical activity, sedentary behaviours and diet quality index for adolescents. Carbohydrate intake was inversely associated with HDL-C (β = − 0·189, P< 0·001). An inverse association was found between fat intake and TAG (β = − 0·319, P< 0·001). Associations between macronutrient intake and serum lipids varied according to adiposity levels, i.e. an inverse association between carbohydrate intake and HDL-C was only observed in those adolescents with a higher waist:height ratio. As serum lipids and excess body fat are the major markers of CVD, these findings should be considered when developing strategies to prevent the risk of CVD among adolescents. AU - Bel-Serrat, Silvia AU - Mouratidou, Theodora AU - Huybrechts, Inge AU - Labayen, Idoia AU - Cuenca-García, Magdalena AU - Palacios, Gonzalo AU - Breidenassel, Christina AU - Molnár, Dénes AU - Roccaldo, Romana AU - Widhalm, Kurt AU - Gottrand, Frederic AU - Kafatos, Anthony AU - Manios, Yannis AU - Vyncke, Krishna AU - Sjöström, Michael AU - Libuda, Lars AU - Gómez-Martínez, Sonia AU - Moreno, Luis A. ID - 27059 JF - British Journal of Nutrition SN - 0007-1145 TI - Associations between macronutrient intake and serum lipid profile depend on body fat in European adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study ER - TY - JOUR AU - Mesch, Christina M. AU - Stimming, Madlen AU - Foterek, Kristina AU - Hilbig, Annett AU - Alexy, Ute AU - Kersting, Mathilde AU - Libuda, Lars ID - 27060 JF - Appetite SN - 0195-6663 TI - Food variety in commercial and homemade complementary meals for infants in Germany. Market survey and dietary practice ER - TY - CONF AU - Mutter, Tobias AU - Kundisch, Dennis ID - 2707 T2 - Proceedings of the International Conference on Information Systems (ICIS) TI - Behavioral Mechanisms Prompted by Badges: The Goal-Gradient Hypothesis ER - TY - CONF AU - Herrmann, Philipp ID - 2708 TI - The Hunt for Quality in a Market: Exploring the Relationship between Local Market Structure and Digitized Customer Experience ER - TY - JOUR AB - This paper studies welfare consequences of consumer-side market transparency with endogenous entry of firms. Different from most studies, we consider the unique symmetric entry equilibrium, which is in mixed strategies. We identify two effects of market transparency on welfare: a competition effect and a novel market-structure effect. We show, surprisingly, that for almost all demand functions the negative market-structure effect eventually dominates the positive competition effect as the market becomes increasingly transparent. Consumer-side market transparency can therefore be socially excessive even without collusion. The only exception among commonly used demand functions is the set of constant demand functions. AU - Gu, Yiquan AU - Hehenkamp, Burkhard ID - 2709 IS - 2 JF - Journal of Institutional and Theoretical Economics JITE SN - 0932-4569 TI - Too Much of a Good Thing? Welfare Consequences of Market Transparency VL - 170 ER - TY - GEN AU - Herrmann, Philipp AU - Rahman, Mohammad ID - 2713 T2 - Workshop on Information Systems & Economics (WISE) TI - The Hunt for Quality in a Market: Exploring the Relationship between Local Market Structure and Digitized Customer Experience ER - TY - CONF AU - John, Thomas ID - 2714 T2 - Proceedings of the Americas' Conference on Information Systems (AMCIS) TI - Modeling Languages for Business Models as Tools for Innovation: Towards a Theoretical Foundation ER - TY - CONF AU - Görzen, Thomas AU - Kundisch, Dennis AU - Ottensmann, C. AU - Haubrock, A. ID - 2715 T2 - Proceedings of the European Electric Vehicle Congress (EEVC) TI - Research on Electric Mobility in Germany: Monitoring a Commercial Battery Electric Vehicle Fleet ER - TY - CONF AU - Keil, Reinhard AU - Selke, Harald AU - Winkelnkemper, Felix ED - Trahasch, Stephan ED - Pl {\ "o} tzner , Rolf ED - Schneider, Gerhard ED - Gayer, Claudia ED - Sassiat, Daniel ED - W {\ "o} hrle, Nicole ID - 27166 TI - Twenty years of learning with the World Wide Web ER - TY - CONF AU - Winkelnkemper, Felix AU - Keil, Reinhard ED - Butz, Andreas ED - Schlichter, Johann ID - 27167 TI - Zwischen Design und Flexibilit{\"a}t - Zur Ergonomie des Flat Design VL - 2014 ER - TY - CONF AU - Weskamp, Christoph AU - John, Thomas AU - Suhl, Leena AU - Kundisch, Dennis AU - Teetz, A. AU - Rose, M. ID - 2717 T2 - Proceedings of the European Electric Vehicle Congress (EEVC) TI - Towards a Simulation-based Approach for Evaluating Business Models for the Electric Vehicle Market ER - TY - CONF AU - John, Thomas AU - Weskamp, Christoph AU - Kundisch, Dennis AU - Suhl, Leena AU - Flake, S. AU - Freund, D. AU - Jung, H. ID - 2718 T2 - Proceedings of the European Electric Vehicle Congress (EEVC) TI - The Case for Modeling Consumer Choice Through an Adapted Total Cost of Ownership Approach ER - TY - GEN AU - Gries, Thomas AU - Meierriecks, Daniel AU - Redlin, Margarete ID - 2731 TI - Providing aid to repressive terrorist source countries does not make the U.S. any safer ER - TY - GEN AU - Gries, Thomas AU - Redlin, Margarete ID - 2732 TI - Maritime Piracy: Socio-Economic, Political, and Institutional Determinants VL - 2014-75 ER - TY - GEN AU - Moritzer, Elmar AU - Budde, C. AU - Leister, C. ID - 27328 SN - 0043-2288 T2 - Welding in the World TI - Affect of Atmospheric Pressure Plasma Pre-Treatment and Aging Conditions on the Surface of Thermoplastics VL - 58 ER - TY - CONF AU - Moritzer, Elmar AU - Martin, Y. AU - Müller, E. AU - Kleeschulte, R. ID - 27330 T2 - 30th International Conference of the Polymer Processing Society (PPS) TI - Artificial Neural Networks to Model Formulation-Property Correlations in the Process of Inline-Compounding on an Injection Moulding Machine ER - TY - CONF AU - Schöppner, Volker AU - Fecke, N. AU - Herken, T. ID - 27331 T2 - 30th International Conference of the Polymer Processing Society (PPS) TI - Analysis of the Material Degradation of PET on a Co-Rotating Twin-Screw Extruder for Varying Vacuum Pressures ER - TY - CONF AU - Schöppner, Volker AU - Littek, S. ID - 27332 T2 - PolyMerTec 2014 TI - Berechnung des Materialabbaus von Thermoplasten während des Plastifiziervorgangs ER - TY - CONF AU - Moritzer, Elmar AU - Seidel, S. ID - 27333 T2 - 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC) TI - Control of Heat Conduction Processes for the Improvement of Part Properties in the Two-Stage GITBlow Process ER - TY - CONF AU - Schöppner, Volker AU - Reinders, F. ID - 27334 T2 - Biobased materials 2014 - 10th Congress for Biobased Materials TI - Development of Wood-Plastic Composites Based on Wood Particles and Dried Blood ER - TY - CONF AU - Moritzer, Elmar ID - 27335 T2 - WAK-Symposium TI - Die Spritzgießsonderverfahren GITBlow, GRIPBlow und Einstufiges GITBlow ER - TY - GEN AU - Moritzer, Elmar AU - Krugmann, J. ID - 27336 IS - 3 SN - 1864-3450 T2 - Joining Plastics TI - Entwicklung einer neuen mechanischen Befestigungslösung mit gleichmäßig krafteinleitenden, dichtendem Hinterschnitt VL - 8 ER - TY - CONF AU - Schöppner, Volker AU - Herken, T. AU - Reinders, F. AU - Westhues, K. ID - 27337 SN - 978-3-18-234335-6 T2 - Erfolgreich Compoundieren mit Pulvern und Stäuben TI - Simulation des Compoundiervorgangs im Doppelschneckenextruder, Modellierung - Simulation - Auslegung ER - TY - CONF AU - Schöppner, Volker AU - Fecke, N. AU - Herken, T. ID - 27338 T2 - 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC) TI - Experimental Analysis of the Material Degradation of PET on a Co-Rotating Twin-Screw Extruder ER - TY - CONF AU - Moritzer, Elmar AU - Heiderich, G. ID - 27339 T2 - 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC) TI - Experimental Investigations of the Mechanical Recycling of Offcuts from the Production of Continuous Fiber-Reinforced Thermoplastic Sheets by Injection Molding ER - TY - CONF AU - Moritzer, Elmar AU - Heiderich, G. ID - 27340 T2 - 58th Ilmenau Scientific Colloquium TI - Experimental Investigations on Injection Molded Parts of Mechanically Recycled Offcuts from the Production of Continuous Fiber-Reinforced Thermoplastic Sheets ER - TY - GEN AU - Schöppner, Volker AU - Brockhaus, S. AU - Klie, B. AU - Giese, U. ID - 27341 IS - 11-12 SN - 0948-3276 T2 - KGK Kautschuk Gummi Kunststoffe TI - Grundlegende Studie und alternative Methode zur Bewertung des Wandgleiteffekts bei hochviskosen Kautschukmischungen VL - 67 ER - TY - CONF AU - Schöppner, Volker AU - Böhm, N. ID - 27342 T2 - 16th Workshop Odour and Emissions of Plastic Materials TI - Herausforderungen bei der Verwendung von Wood-Plastic-Composites(WPC) im Automobilinnenbereich ER - TY - CONF AU - Moritzer, Elmar AU - Budde, C. ID - 27343 T2 - Polymers and Energy TI - Hybrid Lightweight Construction of a Chassis Frame Structure ER - TY - CONF AU - Schöppner, Volker AU - Henke, B. ID - 27344 T2 - 30th International Conference of the Polymer Processing Society (PPS) TI - Illustration of Cross Flows of Polystyrene Melts Through a Coat-Hanger Die ER - TY - GEN AU - Moritzer, Elmar AU - Seidel, S. AU - Gövert, S. AU - Schnieders, J. ID - 27345 IS - 5 SN - 0023-5563 T2 - Kunststoffe TI - Im geschlossenen Werkzeug aufgeblasen VL - 104 ER - TY - CONF AU - Schöppner, Volker AU - Evers, F. ID - 27346 T2 - 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC) TI - Influence of Flame Retardant Material on the Weld Strength of Plastic Parts ER - TY - CONF AU - Moritzer, Elmar AU - Seidel, S. ID - 27347 T2 - 30th International Conference of The Polymer Processing Society (PPS) TI - Influence of Process Parameters on Wall Thickness Distribution During the Initial Step of the Direct GITBlow Process ER - TY - CONF AU - Schöppner, Volker AU - Brockhaus, S. AU - Klie, B. AU - Giese, U. ID - 27348 T2 - 11. Kautschuk-Herbst-Kolloquium (KHK) TI - Investigations about High-Speed Rubber Extrusion ER - TY - CONF AU - Schöppner, Volker AU - Littek, S. ID - 27349 T2 - 30th International Conference of the Polymer Processing Society (PPS) TI - Measurement and Calculation of the Material Degradation of Polystyrene and Modeling of the Degradation by using REX ER - TY - CONF AU - Moritzer, Elmar AU - Krugmann, J. ID - 27350 T2 - 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC) TI - Molded-On Mechanical Fastener Ensures Uniform Force Transmission and Sealing of the Joint Surface: Joining Parts Together with the Aid of Self-Tapping Screws ER - TY - GEN AU - Moritzer, Elmar AU - Kleeschulte, R. ID - 27351 IS - 8 SN - 0023-5563 T2 - Kunststoffe TI - Nicht nur gleich und gleich gesellt sich gern VL - 104 ER - TY - CONF AU - Moritzer, Elmar AU - Krugmann, J. ID - 27352 T2 - PolyMerTec 2014 TI - Nutzung der Materialdeformation zur Entwicklung eines neuartigen Kunststoffblindniets ER - TY - CONF AU - Schöppner, Volker AU - Schadomsky, M. AU - Lemke, F. ID - 27354 T2 - 11. Kautschuk-Herbst-Kolloquium (KHK) TI - Optimisation of the Mixing Behaviour of Rubber Pin-Type Extruders ER - TY - GEN AU - Moritzer, Elmar AU - Budde, C. AU - Tröster, T. AU - Pöhler, S. ID - 27355 IS - 2 SN - 1864-3450 T2 - Joining Plastics TI - Parametereinfluss auf die Verbundfestigkeit einer Organoblech-Kurzfaserthermoplast-Werkstoffkombination VL - 8 ER - TY - CONF AU - Schöppner, Volker AU - Wibbeke, A. ID - 27356 T2 - 30th International Conference of the Polymer Processing Society (PPS) TI - Production of Graded Structures in Films ER - TY - CONF AU - Schöppner, Volker AU - Wibbeke, A. ID - 27357 T2 - 58th Ilmenau Scientific Colloquium TI - Stretching of Polycarbonate ER - TY - CONF AU - Moritzer, Elmar AU - Budde, C. ID - 27358 T2 - 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC) TI - Study of the Bond Strength of a Combination Consisting of Composite Sheet and Short-Fiber Thermoplastic ER - TY - CONF AU - Moritzer, Elmar AU - Budde, C. ID - 27359 T2 - Euro Hybrid Materials and Systems 2014 (EHMS) TI - Study of the Bond Strength of a Combination Consisting of Polypropylene Composite Sheet and Short-Fiber Thermoplastic ER - TY - CONF AU - Schöppner, Volker AU - Evers, F. AU - Lakemeyer, P. ID - 27360 T2 - 67th Annual Assembly of the International Institute of Welding (IIW) TI - The Influence of Welding Processes on the Weld Strength of Flame-Retardant Materials ER - TY - CONF AU - Schöppner, Volker AU - Leßmann, J. ID - 27361 T2 - 30th International Conference of the Polymer Processing Society (PPS) TI - Validation of Discrete Element Simulations in the Field of Solids Conveying in Single-screw Extruders ER -