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See detailStochastic Model Predictive Control for Eco-Driving Assistance Systems in Electric Vehicles
Sajadi Alamdari, Seyed Amin UL

Doctoral thesis (2018)

Electric vehicles are expected to become one of the key elements of future sustainable transportation systems. The first generation of electric cars are already commercially available but still, suffer ... [more ▼]

Electric vehicles are expected to become one of the key elements of future sustainable transportation systems. The first generation of electric cars are already commercially available but still, suffer from problems and constraints that have to be solved before a mass market might be created. Key aspects that will play an important role in modern electric vehicles are range extension, energy efficiency, safety, comfort as well as communication. An overall solution approach to integrating all these aspects is the development of advanced driver assistance systems to make electric vehicles more intelligent. Driver assistance systems are based on the integration of suitable sensors and actuators as well as electronic devices and software-enabled control functionality to automatically support the human driver. Driver assistance for electric vehicles will differ from the already used systems in fuel-powered cars such as electronic stability programs, adaptive cruise control etc. in a way that they must support energy efficiency while the system itself must also have a low power consumption. In this work, an eco-driving functionality as the first step towards those new driver assistance systems for electric vehicles will be investigated. Using information about the internal state of the car, navigation information as well as advanced information about the environment coming from sensors and network connections, an algorithm will be developed that will adapt the speed of the vehicle automatically to minimize energy consumption. From an algorithmic point of view, a stochastic model predictive control approach will be applied and adapted to the special constraints of the problem. Finally, the solution will be tested in simulations as well as in first experiments with a commercial electric vehicle in the SnT Automation & Robotics Research Group (SnT ARG). [less ▲]

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See detailLuxemburgische Intonation: System und Sprachkontakt
Manzoni, Judith Maria UL

Doctoral thesis (2018)

Intonation is usually one of the latest linguistic fields to be investigated in a language, which explains why no systematic approach of the tonal inventory can be found of Luxembourgish, itself a very ... [more ▼]

Intonation is usually one of the latest linguistic fields to be investigated in a language, which explains why no systematic approach of the tonal inventory can be found of Luxembourgish, itself a very young and little researched Germanic language. The main goal of this thesis is therefore to analyze the intonation of Luxembourgish in order to compile a tonal inventory by working on the characteristics of the different intonational patterns used by Luxembourgish native speakers. For this, a formal as well as a functional analysis is carried out, which is used to describe (within the autosegmental-metrical framework) the characteristics of the intonational system. This study establishes six different nuclear patterns, four of which are used in more than one conversational situation, meaning that these situations are not differentiated on the level of intonation. A thorough acoustic analysis depicts the different intonation patterns phonetically, which allows for the comparison of the same conversational situation in different speaking styles (scripted vs. unscripted speech). These findings form the basis for a comparison between the Luxembourgish intonation and the intonation of other languages, which leads to the questions whether the Luxembourgish intonation inventory differs from the ones of the two other official languages in Luxembourg, German and French. This also brings up the question about intonational transfer in the French or German speech of Luxembourgish native speakers. Results show that the German and French intonation systems differ quite strongly from the Luxembourgish system which leads to intonational interferences, even though these interferences are of a different nature in both languages. In brief, this study provides a systematic approach to Luxembourgish intonation and for the first time combines the tonal patterns with their function in discourse while also giving insights into intonational interferences produced by Luxembourgish native speakers in French and German. [less ▲]

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See detailLe contrôle juridictionnel de conventionnalité et de constitutionnalité des lois au Grand-Duché de Luxembourg
Sauer, Carola UL

Doctoral thesis (2018)

The thesis analyses the judicial review of laws, more precisely their compatibility with "higher law" in the Grand Duchy of Luxembourg. Since the 19th century, general courts have authority to review laws ... [more ▼]

The thesis analyses the judicial review of laws, more precisely their compatibility with "higher law" in the Grand Duchy of Luxembourg. Since the 19th century, general courts have authority to review laws as to international law. In 1996/1997, the Constitutional Court was established and empowered to examine ordinary statute law as to their compatibility with the Constitution. As a result, the rule of law might be considered realized. However, the powers of this special court and the legal effects of its judgements are considerably limited. What is more, the analysis of constitutional jurisprudence reveals clear self-limiting tendancies of the constitutional judges themselves. Moreover, it is general wisdom that the Constitutional Court has no authority to review the compatibility of any law with international law. The latter competence is exclusively with the ordinary judge. This situation causes legal uncertainty, bearing the risk of contradictory jurisprudence of high courts. The judicial separation of constitutionality and conventionality review also lacks coherence with respect to the primacy of public international in the Grand-Duchy, and it ignores the existing overlapping of international law and Constitution. [less ▲]

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See detailScience learning in an early childhood classroom in Luxembourg: A journey from sociocultural and cultural historical theories to post-humanism
Haus Geb. Hilgers, Jana Maria UL

Doctoral thesis (2018)

In this dissertation, I map the journey I went on; from applying cultural-historical theory to the application of posthumanist perspectives on science learning and researching science learning in an early ... [more ▼]

In this dissertation, I map the journey I went on; from applying cultural-historical theory to the application of posthumanist perspectives on science learning and researching science learning in an early childhood classroom in Luxembourg. Within this work, I show the process of realizing that the theories I applied for a certain amount of time at the beginning of the Ph.D. revealed a gap to me concerning what I wanted to achieve in the field of researching science learning. I draw on posthumanist perspectives to elaborate broader views of the research process to show how each (human and non-human) participant contributes to the context of science education with young children in Luxembourg. I also I present findings that changed my perspective on research and data analysis with young children in the field of science education. In sharing my reflexive journey, I contribute to ongoing methodological and ethical discussions about the research process with – rather than on – young children, as well as working to increase awareness of the importance of the researcher's stance and positioning towards both human and non-human research participants in Luxembourg classrooms. In the chapters that follow, I show the trajectory of how I applied sociocultural and later posthumanist theory and ethnographic video analysis to data I collected in one Kindergarten science classroom in Luxembourg. Findings of this journey show how human and non-human beings work together, and provide impulses for researchers to situate themselves reflexively to consider why and how they are doing research and what they hope to gain from it. This is not to promote a narcissistic and self-indulgent view of the researcher, but to point out what might be missing from some research reports that claim to be participatory when in fact they reproduce the researcher's perspectives of the children's view and "sell" it as their own, instead of listening and including participants’ voices. In order to link this to posthumanist theory and agential realism (e.g., Barad, 2007), this thesis theorizes research processes in ways that not only take into account who is researching whom, but that draw attention to the surrounding entanglements that constitute research, and how the research itself changes and is changed by the participating human and non-human beings. The papers assembled below show how all participating (human and non-human) beings are entangled and together become through and for one another. [less ▲]

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See detailPRESENCE: Toward a Novel Approach for Performance Evaluation of Mobile Cloud SaaS Web Services
Ibrahim, Abdallah Ali Zainelabden Abdallah UL; Varrette, Sébastien UL; Bouvry, Pascal UL

in Proc. of the 32nd IEEE Intl. Conf. on Information Networking (ICOIN 2018) (2018, January)

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See detailA lifting method for analyzing distributed synchronization on the unit sphere
Thunberg, Johan UL; Markdahl, Johan UL; Bernard, Florian et al

in Automatica (2018)

This paper introduces a new lifting method for analyzing convergence of continuous-time distributed synchronization/consensus systems on the unit sphere. Points on the d-dimensional unit sphere are lifted ... [more ▼]

This paper introduces a new lifting method for analyzing convergence of continuous-time distributed synchronization/consensus systems on the unit sphere. Points on the d-dimensional unit sphere are lifted to the (d+1)-dimensional Euclidean space. The consensus protocol on the unit sphere is the classical one, where agents move toward weighted averages of their neighbors in their respective tangent planes. Only local and relative state information is used. The directed interaction graph topologies are allowed to switch as a function of time. The dynamics of the lifted variables are governed by a nonlinear consensus protocol for which the weights contain ratios of the norms of state variables. We generalize previous convergence results for hemispheres. For a large class of consensus protocols defined for switching uniformly quasi-strongly connected time-varying graphs, we show that the consensus manifold is uniformly asymptotically stable relative to closed balls contained in a hemisphere. Compared to earlier projection based approaches used in this context such as the gnomonic projection, which is defined for hemispheres only, the lifting method applies globally. With that, the hope is that this method can be useful for future investigations on global convergence. [less ▲]

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See detailA training-resistant anomaly detection system
Muller, Steve UL; Lancrenon, Jean; Harpes, Carlo et al

in Computers and Security (2018), 76

Modern network intrusion detection systems rely on machine learning techniques to detect traffic anomalies and thus intruders. However, the ability to learn the network behaviour in real-time comes at a ... [more ▼]

Modern network intrusion detection systems rely on machine learning techniques to detect traffic anomalies and thus intruders. However, the ability to learn the network behaviour in real-time comes at a cost: malicious software can interfere with the learning process, and teach the intrusion detection system to accept dangerous traffic. This paper presents an intrusion detection system (IDS) that is able to detect common network attacks including but not limited to, denial-of-service, bot nets, intrusions, and network scans. With the help of the proposed example IDS, we show to what extent the training attack (and more sophisticated variants of it) has an impact on machine learning based detection schemes, and how it can be detected. © 2018 Elsevier Ltd [less ▲]

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See detailUsing Regularization to Infer Cell Line Specificity in Logical Network Models of Signaling Pathways.
De Landtsheer, Sébastien; Lucarelli, Philippe UL; Sauter, Thomas UL

in Frontiers in physiology (2018), 9

Understanding the functional properties of cells of different origins is a long-standing challenge of personalized medicine. Especially in cancer, the high heterogeneity observed in patients slows down ... [more ▼]

Understanding the functional properties of cells of different origins is a long-standing challenge of personalized medicine. Especially in cancer, the high heterogeneity observed in patients slows down the development of effective cures. The molecular differences between cell types or between healthy and diseased cellular states are usually determined by the wiring of regulatory networks. Understanding these molecular and cellular differences at the systems level would improve patient stratification and facilitate the design of rational intervention strategies. Models of cellular regulatory networks frequently make weak assumptions about the distribution of model parameters across cell types or patients. These assumptions are usually expressed in the form of regularization of the objective function of the optimization problem. We propose a new method of regularization for network models of signaling pathways based on the local density of the inferred parameter values within the parameter space. Our method reduces the complexity of models by creating groups of cell line-specific parameters which can then be optimized together. We demonstrate the use of our method by recovering the correct topology and inferring accurate values of the parameters of a small synthetic model. To show the value of our method in a realistic setting, we re-analyze a recently published phosphoproteomic dataset from a panel of 14 colon cancer cell lines. We conclude that our method efficiently reduces model complexity and helps recovering context-specific regulatory information. [less ▲]

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See detailAnalysis of carbohydrate degradation during fermentation by an adapted Anthron-method
Greger, Manfred UL; Schlienz, Markus UL; Benito Martin, Patricia Cristina UL

in Landtechnik (2018)

To measure the degradation of carbohydrates during fermentation the photometrical Anthron method has been adapted. The method has been verified in mesophilic batch tests with the model substrates glucose ... [more ▼]

To measure the degradation of carbohydrates during fermentation the photometrical Anthron method has been adapted. The method has been verified in mesophilic batch tests with the model substrates glucose (water-soluble), corn-starch and cellulose (both insoluble in water). First, the content of soluble carbohydrates was measured. For determination of carbo-hydrates in soluble phase, the samples were filtered (syringe PTFE-filter with mesh size 0.45 μm) to separate the solution from all types of particles, particulate carbohydrates included. The soluble phase reacted with the Anthron solution for 8 minutes at 100 °C. Afterwards, the coloration reaction was stopped by a quick (5 min) cooling step in ice water to ensure repeatability of the method considering a larger number of samples to be measured. Afterwards samples had been equilibrated at room temperature for at least 30 minutes. Before measurement, the sample had to be diluted to reduce on the one hand the intensity of the background and on the other hand to obtain the measuring range (l = 625 nm) of soluble carbohydrates of 10 to 100 mg/l. The total carbohydrate content, which consists of the soluble and particulate fraction, was determined by an additional pre-hydrolysis step (50 % sulfuric acid at 100 °C during 8 minutes) before the Anthron reaction was started. To measure insoluble carbohydrates, e.g. starch and cellulose, they had to pass an additional pre-hydrolysis step, which is performed before filtration and the subsequent Anthron reaction. This additional step (in the following called “indirect method”) is necessary to measure the part of insoluble respectively polymeric carbohydrates of a sample. The amount of particulate carbohydrates is further be calculated by the difference between total and soluble carbohydrates. [less ▲]

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See detailTesting Autonomous Cars for Feature Interaction Failures using Many-Objective Search
Ben Abdessalem (helali), Raja UL; Panichella, Annibale; Nejati, Shiva UL et al

in Proceedings of the 33rd IEEE/ACM International Conference on Automated Software Engineering (ASE 2018) (2018)

Complex systems such as autonomous cars are typically built as a composition of features that are independent units of functionality. Features tend to interact and impact one another’s behavior in unknown ... [more ▼]

Complex systems such as autonomous cars are typically built as a composition of features that are independent units of functionality. Features tend to interact and impact one another’s behavior in unknown ways. A challenge is to detect and manage feature interactions, in particular, those that violate system requirements, hence leading to failures. In this paper, we propose a technique to detect feature interaction failures by casting our approach into a search-based test generation problem. We define a set of hybrid test objectives (distance functions) that combine traditional coverage-based heuristics with new heuristics specifically aimed at revealing feature interaction failures. We develop a new search-based test generation algorithm, called FITEST, that is guided by our hybrid test objectives. FITEST extends recently proposed many-objective evolutionary algorithms to reduce the time required to compute fitness values. We evaluate our approach using two versions of an industrial self-driving system. Our results show that our hybrid test objectives are able to identify more than twice as many feature interaction failures as two baseline test objectives used in the software testing literature (i.e., coverage-based and failure-based test objectives). Further, the feedback from domain experts indicates that the detected feature interaction failures represent real faults in their systems that were not previously identified based on analysis of the system features and their requirements. [less ▲]

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See detailLe droit commun et l'avenir du droit luxembourgeois
Kinsch, Patrick UL

in Actes de la Section des sciences morales et politiques (2018), XXI

Le droit commun est un ensemble de règles ordinaires, censées être équilibrées, qui évite le spectaculaire, l’exorbitant, les privilèges. En droit privé, c’est (pour faire bref et un peu inexact) le droit ... [more ▼]

Le droit commun est un ensemble de règles ordinaires, censées être équilibrées, qui évite le spectaculaire, l’exorbitant, les privilèges. En droit privé, c’est (pour faire bref et un peu inexact) le droit du Code civil ; au-delà du droit civil, il existe du droit commun dans toutes les branches du droit, même en droit fiscal. Ne sous-estimons pas le droit commun ; il est précieux. Mais a-t-il un véritable avenir au Luxembourg ? Il a quelques alliés, il est vrai : le contrôle de la constitutionnalité des lois, et le contrôle des clauses abusives dans les contrats. Deux puissants facteurs jouent cependant contre lui : 1° le manque, paradoxal mais réel, de ressources qui permettraient de faire évoluer le droit commun, en particulier sur le plan législatif ; 2° le souhait de le remplacer par du droit dérogatoire (et compétitif dans le marché international des normes), qui n’a aucune des caractéristiques, rappelées ci-dessus, du droit commun. [less ▲]

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See detailLoss of inter-cellular cooperation by complete epithelial-mesenchymal transition supports favorable outcomes in basal breast cancer patients
Grosse-Wilde, Anne; Kuestner, Rolf E.; Skelton, Stephanie M. et al

in Oncotarget (2018), 9(28), 20018

According to the sequential metastasis model, aggressive mesenchymal (M) metastasis-initiating cells (MICs) are generated by an epithelial-mesenchymal transition (EMT) which eventually is reversed by a ... [more ▼]

According to the sequential metastasis model, aggressive mesenchymal (M) metastasis-initiating cells (MICs) are generated by an epithelial-mesenchymal transition (EMT) which eventually is reversed by a mesenchymal-epithelial transition (MET) and outgrowth of life-threatening epithelial (E) macrometastases. Paradoxically, in breast cancer M signatures are linked with more favorable outcomes than E signatures, and M cells are often dispensable for metastasis in mouse models. Here we present evidence at the cellular and patient level for the cooperation metastasis model, according to which E cells are MICs, while M cells merely support E cell persistence through cooperation. We tracked the fates of co-cultured E and M clones and of fluorescent CDH1-promoter-driven cell lines reporting the E state derived from basal breast cancer HMLER cells. Cells were placed in suspension state and allowed to reattach and select an EMT cell fate. Flow cytometry, single cell and bulk gene expression analyses revealed that only pre-existing E cells generated E cells, mixed E/M populations, or stem-like hybrid E/M cells after suspension and that complete EMT manifest in M clones and CDH1-negative reporter cells resulted in loss of cell plasticity, suggesting full transdifferentiation. Mechanistically, E-M coculture experiments supported the persistence of pre-existing E cells where M cells inhibited EMT of E cells in a mutual cooperation via direct cell-cell contact. Consistently, M signatures were associated with more favorable patient outcomes compared to E signatures in breast cancer, specifically in basal breast cancer patients. These findings suggest a potential benefit of complete EMT for basal breast cancer patients. [less ▲]

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See detailCaSiAn: a Calcium Signaling Analyzer tool
Moein, Mahsa UL; Grzyb, Kamil UL; Gonçalves Martins, Teresa et al

in Bioinformatics (2018), 1

Ca2þ is a central second messenger in eukaryotic cells that regulates many cellular proc- esses. Recently, we have indicated that typical Ca2þ signals are not purely oscillatory as widely assumed, but ... [more ▼]

Ca2þ is a central second messenger in eukaryotic cells that regulates many cellular proc- esses. Recently, we have indicated that typical Ca2þ signals are not purely oscillatory as widely assumed, but exhibit stochastic spiking with cell type and pathway specific characteristics. Here, we present the Calcium Signaling Analyzer (CaSiAn), an open source software tool that allows for quantifying these signal characteristics including individual spike properties and time course statis- tics in a semi-automated manner. CaSiAn provides an intuitive graphical user interface allowing experimentalists to easily process a large amount of Ca2þ signals, interactively tune peak detection, revise statistical measures and access the quantified signal properties as excel or text files. [less ▲]

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See detailLuxembourg and the EU: How to Integrate in the Face of Diversity
Högenauer, Anna-Lena UL

in Kaeding, Michael; Pollack, Johannes; Schmidt, Paul (Eds.) The Future of Europe: Views from the Capitals (2018)

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See detailActivity of translation regulator eukaryotic elongation factor-2 kinase is increased in Parkinson disease brain and its inhibition reduces alpha synuclein toxicity
Jan, Asad; Jansonius, Brandon; Delaidelli, Alberto et al

in Acta Neuropathologica Communications (2018)

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See detailTongji-Grace02s and Tongji-Grace02k: high-precision static GRACE-only global Earth's gravity field models derived by refined data processing strategies
Qiujie, Chen; Yunzhong, Shen; Francis, Olivier UL et al

in Journal of Geophysical Research: Solid Earth (2018), 0(ja),

Abstract In order to derive high-precision static GRACE-only gravity field solutions, the following strategies were implemented in this study: (1) a refined accelerometer calibration model that treats ... [more ▼]

Abstract In order to derive high-precision static GRACE-only gravity field solutions, the following strategies were implemented in this study: (1) a refined accelerometer calibration model that treats monthly accelerometer scales as a 3-order polynomial and daily accelerometer biases as a 5-order polynomial was developed to calibrate accelerometer measurements; (2) the errors of the acceleration and attitude data were estimated together with the geopotential coefficients and accelerometer parameters on the basis of the weighted least-squares adjustments; (3) a nearly complete observation series of GRACE mission was used to decrease the condition number of normal equation; and (4) the GRACE data collected in lower orbit altitude were also included to decrease the condition number. Our results show that: (1) the refined accelerometer calibration model with much less parameters performs as well as previous methods (i.e. solving daily scales and hourly biases or estimating biases along with bias rates every two hours). However, it provides a system of more stable normal equation and less high-frequency noise in gravity field solutions; (2) high-frequency noise in the gravity field solution is reduced by modelling the errors of the acceleration and attitude data; (3) the geopotential coefficients at all degrees is greatly enhanced by using longer GRACE time series (especially the data by the end of 2010); and (4) due to lower orbit altitude, the GRACE data collected since 2014 lead to a significant improvement of the gravity field solution as the satellites are more sensitive to higher-frequency signal. Using the refined strategies, an unconstrained static solution (named Tongji-Grace02s) up to degree and order 180 was derived. For further suppressing the high-frequency noise, a regularization strategy based on the Kaula rule is applied to the degrees and orders beyond 80, leading to a regularized model Tongji-Grace02k. To validate the quality of the derived models, both Tongji-Grace02s and Tongji-Grace02k were compared to the latest GRACE-only models (i.e. GGM05S, ITU\_GRACE16, ITSG-Grace2014s and ITSG-Grace2014k) and validated using independent data (i.e. GNSS/Levelling data and DTU13 oceanic gravity data). Compared to other models, much less spatial noise in terms of global gravity anomalies with respect to the state-of-the-art model EIGEN6C4 and far higher accuracy at high degrees are achieved by Tongji-Grace02s. The same conclusions can be drawn for Tongji-Grace02k when the same analyses were applied to the regularized solutions ITSG-Grace2014k and Tongji-Grace02k. Validations with independent data confirm that Tongji-Grace02s has the least noise among the unconstrained GRACE-only models and Tongji-Grace02k is the one with the best accuracy among the regularized GRACE-only solutions. For the tests up to degree and order 180 using GNSS/Levelling data, the improvements of Tongji-Grace02s with respect to ITSG-Grace2014s reach 13\% over the Canada and 23\% in the Mexico. Even better, no less than 58\% of improvement is achieved by both Tongji-Grace02s relative to ITSG-Grace2014s and Tongji-Grace02k with respect to ITSG-Grace2014k in the validation based on DTU13 data. [less ▲]

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